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Sample records for regulates developmental progression

  1. Developmental Regulation with Progressive Vision Loss: Use of Control Strategies and Affective Well-Being

    ERIC Educational Resources Information Center

    Schilling, Oliver K.; Wahl, Hans-Werner; Boerner, Kathrin; Horowitz, Amy; Reinhardt, Joann P.; Cimarolli, Verena R.; Brennan-Ing, Mark; Heckhausen, Jutta

    2016-01-01

    The present study addresses older adults' developmental regulation when faced with progressive and irreversible vision loss. We used the motivational theory of life span development as a conceptual framework and examined changes in older adults' striving for control over everyday goal achievement, and their association with affective well-being,…

  2. OLA1, a Translational Regulator of p21, Maintains Optimal Cell Proliferation Necessary for Developmental Progression

    PubMed Central

    Ding, Zonghui; Liu, Yue; Rubio, Valentina; He, Jinjie; Minze, Laurie J.

    2016-01-01

    OLA1, an Obg-family GTPase, has been implicated in eukaryotic initiation factor 2 (eIF2)-mediated translational control, but its physiological functions remain obscure. Here we report that mouse embryos lacking OLA1 have stunted growth, delayed development leading to immature organs—especially lungs—at birth, and frequent perinatal lethality. Proliferation of primary Ola1−/− mouse embryonic fibroblasts (MEFs) is impaired due to defective cell cycle progression, associated with reduced cyclins D1 and E1, attenuated Rb phosphorylation, and increased p21Cip1/Waf1. Accumulation of p21 in Ola1−/− MEFs is due to enhanced mRNA translation and can be prevented by either reconstitution of OLA1 expression or treatment with an eIF2α dephosphorylation inhibitor, suggesting that OLA1 regulates p21 through a translational mechanism involving eIF2. With immunohistochemistry, overexpression of p21 protein was detected in Ola1-null embryos with reduced cell proliferation. Moreover, we have generated p21−/− Ola1−/− mice and found that knockout of p21 can partially rescue the growth retardation defect of Ola1−/− embryos but fails to rescue them from developmental delay and the lethality. These data demonstrate, for the first time, that OLA1 is required for normal progression of mammalian development. OLA1 plays an important role in promoting cell proliferation at least in part through suppression of p21 and organogenesis via factors yet to be discovered. PMID:27481995

  3. Regulation of early T-lineage gene expression and developmental progression by the progenitor cell transcription factor PU.1

    PubMed Central

    Champhekar, Ameya; Damle, Sagar S.; Freedman, George; Carotta, Sebastian; Nutt, Stephen L.

    2015-01-01

    The ETS family transcription factor PU.1 is essential for the development of several blood lineages, including T cells, but its function in intrathymic T-cell precursors has been poorly defined. In the thymus, high PU.1 expression persists through multiple cell divisions in early stages but then falls sharply during T-cell lineage commitment. PU.1 silencing is critical for T-cell commitment, but it has remained unknown how PU.1 activities could contribute positively to T-cell development. Here we employed conditional knockout and modified antagonist PU.1 constructs to perturb PU.1 function stage-specifically in early T cells. We show that PU.1 is needed for full proliferation, restricting access to some non-T fates, and controlling the timing of T-cell developmental progression such that removal or antagonism of endogenous PU.1 allows precocious access to T-cell differentiation. Dominant-negative effects reveal that this repression by PU.1 is mediated indirectly. Genome-wide transcriptome analysis identifies novel targets of PU.1 positive and negative regulation affecting progenitor cell signaling and cell biology and indicating distinct regulatory effects on different subsets of progenitor cell transcription factors. Thus, in addition to supporting early T-cell proliferation, PU.1 regulates the timing of activation of the core T-lineage developmental program. PMID:25846797

  4. Cyclic compressive stress-induced scinderin regulates progress of developmental dysplasia of the hip.

    PubMed

    Wang, Cheng-Long; Wang, Hui; Xiao, Fei; Wang, Chuan-Dong; Hu, Guo-Li; Zhu, Jun-Feng; Shen, Chao; Zuo, Bin; Cui, Yi-Min; Li, De; Yuan-Gao; Zhang, Xiao-Ling; Chen, Xiao-Dong

    2017-02-14

    Developmental dysplasia of the hip (DDH) is a common musculoskeletal disorder characterized by a mismatch between acetabulum and femoral head. Mechanical force plays an important role during the occurrence and development of abnormities in acetabulum and femoral head. In this study, we established a mechanical force model named cyclic compressive stress (Ccs). To analyze the effect of Ccs on DDH, we detected special genes in chondrocytes and osteoblasts. Results showed that Ccs downregulated chondrogenesis of ADTC5 in a concentration-dependent manner. Moreover, the mRNA level of Scinderin (Scin) considerably increased. We established lentivirus-SCIN(GV144-SCIN) to transfect hBMSCs, which were treated with different Ccs levels (0.25 Hz*5 cm, 0.5 Hz*5 cm, and 1 Hz*10 cm); the result showed that overexpression of Scin upregulated osteogenesis and osteoclastogenesis. By contrast, expression of chondrocyte-specific genes, including ACAN, COL-2A, and Sox9, decreased. Further molecular investigation demonstrated that Scin promoted osteogenesis and osteoclastogenesis through activation of the p-Smad1/5/8, NF-κB, and MAPK P38 signaling pathways, as well as stimulated the expression of key osteoclast transcriptional factors NFATc1 and c-Fos. Moreover, Scin-induced osteogenesis outweighed osteoclastogenesis in defective femur in vivo. The results of the analysis of Micro-CT confirmed these findings. Overall, Ccs influenced the development of DDH by promoting osteogenesis and cartilage degradation. In addition, Scin played a vital role in the development of DDH.

  5. The Homeodomain Iroquois Proteins Control Cell Cycle Progression and Regulate the Size of Developmental Fields.

    PubMed

    Barrios, Natalia; González-Pérez, Esther; Hernández, Rosario; Campuzano, Sonsoles

    2015-08-01

    During development, proper differentiation and final organ size rely on the control of territorial specification and cell proliferation. Although many regulators of these processes have been identified, how both are coordinated remains largely unknown. The homeodomain Iroquois/Irx proteins play a key, evolutionarily conserved, role in territorial specification. Here we show that in the imaginal discs, reduced function of Iroquois genes promotes cell proliferation by accelerating the G1 to S transition. Conversely, their increased expression causes cell-cycle arrest, down-regulating the activity of the Cyclin E/Cdk2 complex. We demonstrate that physical interaction of the Iroquois protein Caupolican with Cyclin E-containing protein complexes, through its IRO box and Cyclin-binding domains, underlies its activity in cell-cycle control. Thus, Drosophila Iroquois proteins are able to regulate cell-autonomously the growth of the territories they specify. Moreover, our results provide a molecular mechanism for a role of Iroquois/Irx genes as tumour suppressors.

  6. Developmental Progress in Institutional and Community Settings.

    ERIC Educational Resources Information Center

    Sokol-Kessler, Leslie E.; And Others

    1983-01-01

    Comparison of developmental growth for 104 matched pairs from mentally retarded residents of a public institution and of community living arrangements (CLA) revealed that CLA Ss showed significant developmental progress in reduction of maladaptive behavior while institutionalized Ss showed no change over 2 years. (Author/CL)

  7. Developmental regulation of embryonic genes in plants

    SciTech Connect

    Borkird, C.; Choi, Jung, H.; Jin, Zhenghua; Franz, G.; Hatzopoulos, P.; Chorneaus, R.; Bonas, U.; Pelegri, F.; Sung, Z.R.

    1988-09-01

    Somatic embryogenesis from cultured carrot cells progresses through successive morphogenetic stages termed globular, heart, and torpedo. To understand the molecular mechanisms underlying plant embryogenesis, the authors isolated two genes differentially expressed during embryo development. The expression of these two genes is associated with heart-stage embryogenesis. By altering the culture conditions and examining their expressions in a developmental variant cell line, they found that these genes were controlled by the developmental program of embryogenesis and were not directly regulated by 2,4-dichlorophenoxyacetic acid, the growth regulator that promotes unorganized growth of cultured cells and suppresses embryo morphogenesis. These genes are also expressed in carrot zygotic embryos but not in seedlings or mature plants.

  8. Copper Homeostasis for the Developmental Progression of Intraerythrocytic Malarial Parasite

    PubMed Central

    Asahi, Hiroko; Kobayashi, Fumie; Inoue, Shin-Ichi; Niikura, Mamoru; Yagita, Kenji; Tolba, Mohammed Essa Marghany

    2016-01-01

    Malaria is one of the world’s most devastating diseases, particularly in the tropics. In humans, Plasmodium falciparum lives mainly within red blood cells, and malaria pathogenesis depends on the red blood cells being infected with the parasite. Non-esterified fatty acids (NEFAs), including cis-9-octadecenoic acid, and phospholipids have been critical for complete parasite growth in serum-free culture, although the efficacy of NEFAs in sustaining the growth of P. falciparum has varied markedly. Hexadecanoic acid and trans-9-octadecenoic acid have arrested development of the parasite, in association with down-regulation of genes encoding copper-binding proteins. Selective removal of Cu+ ions has blockaded completely the ring–trophozoite–schizont progression of the parasite. The importance of copper homeostasis for the developmental progression of P. falciparum has been confirmed by inhibition of copper-binding proteins that regulate copper physiology and function by associating with copper ions. These data have provided strong evidence for a link between healthy copper homeostasis and successive developmental progression of P. falciparum. Perturbation of copper homeostasis may be, thus, instrumental in drug and vaccine development for the malaria medication. We review the importance of copper homeostasis in the asexual growth of P. falciparum in relation to NEFAs, copper-binding proteins, apoptosis, mitochondria, and gene expression. PMID:26881705

  9. Developmental Regulation of the Collagenase-3 Promoter in Osteoblasts

    NASA Technical Reports Server (NTRS)

    Partridge, N. C.; Yang, Y.; DAlonzo, R. C.; Winchester, S. K.

    1999-01-01

    Previously, we have shown that collagenase-3 MRNA is developmentally expressed in normal, differentiating rat osteoblasts. In vivo, the gene is expressed in a tissue-specific fashion in hypertrophic chondrocytes and osteoblasts and developmentally regulated. Our studies aim at determining the promoter elements and proteins binding to the promoter responsible for tissue and developmental regulation of collagenase-3.

  10. Temporal regulation of mRNAs for select bone morphogenetic proteins (BMP), BMP receptors and their associated SMAD proteins during bovine early embryonic development: effects of exogenous BMP2 on embryo developmental progression

    PubMed Central

    2014-01-01

    blastocyst mRNA for CDX2 and NANOG. Conclusions Abundance of maternally derived mRNAs for above BMP system components are dynamically regulated during oocyte maturation and early embryogenesis. Exogenous BMP2 treatment does not influence progression to various developmental endpoints, but impacts characteristics of resulting blastocysts. Results support a potential role for BMPs in bovine early embryogenesis. PMID:25027287

  11. Progressive Education as Continuing Education for the Developmentally Disabled

    ERIC Educational Resources Information Center

    Boedicker, Leslie Kuhn

    2013-01-01

    The need for progressive education is prevalent in one of the most underserved portions of the population: the adult developmentally disabled. Though John Dewey wrote little on the education of the disabled, his philosophy, and that of Mahatma Gandhi's, lend themselves to the further education of this unique segment of society. In this paper, I…

  12. Retinoids regulate a developmental checkpoint for tissue regeneration in Drosophila

    PubMed Central

    Halme, Adrian; Cheng, Michelle; Hariharan, Iswar K.

    2010-01-01

    Summary Drosophila melanogaster larvae have a remarkable capacity for regenerative growth: Damage to their imaginal discs, the larval precursors of adult structures, elicits a robust proliferative response from the surviving tissue [1–4]. However, as in other organisms, developmental progression and differentiation can restrict regenerative capacity of Drosophila tissues. Experiments in Drosophila and other holometabolous insects have demonstrated that either damage to imaginal tissues [5, 6] or transplantation of a damaged imaginal disc [7, 8] delays the onset of metamorphosis, a time when the imaginal discs undergo morphogenesis and differentiation into their adult structures. Therefore, in Drosophila there appears to be a mechanism that senses tissue damage and extends the larval phase to coordinate tissue regeneration with the overall developmental program of the organism. However, how such a pathway functions remains unknown. Here we demonstrate that a developmental checkpoint extends larval growth after imaginal disc damage by inhibiting the transcription of the gene encoding PTTH, a neuropeptide that promotes the release of the steroid hormone ecdysone. Using a genetic screen, we identify a previously unsuspected role for retinoid biosynthesis in regulating PTTH expression and delaying development in response to tissue damage. Retinoid signaling plays an important, but poorly defined role in several vertebrate regeneration models [9–11]. Our findings demonstrate that retinoid biosynthesis in Drosophila is important for the maintenance of a permissive condition for regenerative growth. PMID:20189388

  13. Developmental Regulation across the Life Span: Toward a New Synthesis

    ERIC Educational Resources Information Center

    Haase, Claudia M.; Heckhausen, Jutta; Wrosch, Carsten

    2013-01-01

    How can individuals regulate their own development to live happy, healthy, and productive lives? Major theories of developmental regulation across the life span have been proposed (e.g., dual-process model of assimilation and accommodation; motivational theory of life-span development; model of selection, optimization, and compensation), but they…

  14. Prothoracicotropic hormone regulates developmental timing and body size in Drosophila

    PubMed Central

    McBrayer, Zofeyah; Ono, Hajime; Shimell, MaryJane; Parvy, Jean-Philippe; Beckstead, Robert B.; Warren, James T.; Thummel, Carl S.; Dauphin-Villemant, Chantal; Gilbert, Lawrence I.; O’Connor, Michael B.

    2008-01-01

    Summary In insects, control of body size is intimately linked to nutritional quality as well as environmental and genetic cues that regulate the timing of developmental transitions. Prothoracicotropic hormone (PTTH) has been proposed to play an essential role in regulating the production and/or release of ecdysone, a steroid hormone that stimulates molting and metamorphosis. In this report we examine the consequences on Drosophila development of ablating the PTTH-producing neurons. Surprisingly, PTTH production is not essential for molting or metamorphosis. Instead, loss of PTTH results in delayed larval development and eclosion of larger flies with more cells. Prolonged feeding, without changing the rate of growth, causes the developmental delay and is a consequence of low ecdysteroid titers. These results indicate that final body size in insects is determined by a balance between growth rate regulators such as insulin and developmental timing cues such as PTTH that set the duration of the feeding interval. PMID:18061567

  15. Dynamic CRM occupancy reflects a temporal map of developmental progression.

    PubMed

    Wilczyński, Bartek; Furlong, Eileen E M

    2010-06-22

    Development is driven by tightly coordinated spatio-temporal patterns of gene expression, which are initiated through the action of transcription factors (TFs) binding to cis-regulatory modules (CRMs). Although many studies have investigated how spatial patterns arise, precise temporal control of gene expression is less well understood. Here, we show that dynamic changes in the timing of CRM occupancy is a prevalent feature common to all TFs examined in a developmental ChIP time course to date. CRMs exhibit complex binding patterns that cannot be explained by the sequence motifs or expression of the TFs themselves. The temporal changes in TF binding are highly correlated with dynamic patterns of target gene expression, which in turn reflect transitions in cellular function during different stages of development. Thus, it is not only the timing of a TF's expression, but also its temporal occupancy in refined time windows, which determines temporal gene expression. Systematic measurement of dynamic CRM occupancy may therefore serve as a powerful method to decode dynamic changes in gene expression driving developmental progression.

  16. Developmental regulation of X-chromosome inactivation.

    PubMed

    Payer, Bernhard

    2016-08-01

    With the emergence of sex-determination by sex chromosomes, which differ in composition and number between males and females, appeared the need to equalize X-chromosomal gene dosage between the sexes. Mammals have devised the strategy of X-chromosome inactivation (XCI), in which one of the two X-chromosomes is rendered transcriptionally silent in females. In the mouse, the best-studied model organism with respect to XCI, this inactivation process occurs in different forms, imprinted and random, interspersed by periods of X-chromosome reactivation (XCR), which is needed to switch between the different modes of XCI. In this review, I describe the recent advances with respect to the developmental control of XCI and XCR and in particular their link to differentiation and pluripotency. Furthermore, I review the mechanisms, which influence the timing and choice, with which one of the two X-chromosomes is chosen for inactivation during random XCI. This has an impact on how females are mosaics with regard to which X-chromosome is active in different cells, which has implications on the severity of diseases caused by X-linked mutations.

  17. Developmental Gene Regulation and Mechanisms of Evolution

    NASA Technical Reports Server (NTRS)

    1998-01-01

    The Marine Biological Laboratory and the National Aeronautics and Space Administration have established a cooperative agreement with the formation of a Center for Advanced Studies 'in the Space Life Sciences (CASSLS) at the MBL. This Center serves as an interface between NASA and the basic science community, addressing issues of mutual interest. The Center for Advanced Studies 'in the Space Life Sciences provides a forum for scientists to think and discuss, often for the first time, the role that gravity and aspects of spaceflight may play 'in fundamental cellular and physiologic processes. In addition the Center will sponsor discussions on evolutionary biology. These interactions will inform the community of research opportunities that are of interest to NASA. This workshop is one of a series of symposia, workshops and seminars that will be held at the MBL to advise NASA on a wide variety of topics in the life sciences, including cell biology, developmental biology, mg evolutionary biology, molecular biology, neurobiology, plant biology and systems biology.

  18. The GATA transcription factor GtaC regulates early developmental gene expression dynamics in Dictyostelium.

    PubMed

    Santhanam, Balaji; Cai, Huaqing; Devreotes, Peter N; Shaulsky, Gad; Katoh-Kurasawa, Mariko

    2015-07-06

    In many systems, including the social amoeba Dictyostelium discoideum, development is often marked by dynamic morphological and transcriptional changes orchestrated by key transcription factors. However, efforts to examine sequential genome-wide changes of gene regulation in developmental processes have been fairly limited. Here we report the developmental regulatory dynamics of GtaC, a GATA-type zinc-finger transcription factor, through the analyses of serial ChIP- and RNA-sequencing data. GtaC is essential for developmental progression, decoding extracellular cAMP pulses during early development and may play a role in mediating cell-type differentiation at later stages. We find that GtaC exhibits temporally distinctive DNA-binding patterns concordant with each developmental stage. We identify direct GtaC targets and observe cotemporaneous GtaC-binding and developmental expression regulation. Our results suggest that GtaC regulates multiple physiological processes as Dictyostelium transitions from a group of unicellular amoebae to an integrated multicellular organism.

  19. Developmental College Student Self-Regulation: Results from Two Measures

    ERIC Educational Resources Information Center

    Young, Dawn; Ley, Kathryn

    2005-01-01

    This study compared 34 lower-achieving (developmental) first-time college students' self-reported self-regulation strategies from a Likert scale to those they reported in structured interviews. Likert scales have offered convenient administration and evaluation and have been used to identify what and how learners study. The reported study activity…

  20. Regulation of terpene metabolism. Progress report

    SciTech Connect

    Croteau, R.

    1983-01-01

    Progress is reported in the following research areas: function of monoterpene catabolism; pathways and enzymes of monoterpene catabolism; ultrastructure of oil glands; pathways and enzymes of monoterpene biosynthesis; and regulation of metabolism in peppermints. (ACR)

  1. Developmental Psychology and Public Policy: Progress and Prospects

    ERIC Educational Resources Information Center

    Foster, E. Michael; Kalil, Ariel

    2005-01-01

    This article outlines a framework for developmentally oriented policy research. Drawing from U. Bronfenbrenner's (1995) dynamic developmental systems theory, the authors suggest ways in which the key tenets of process, persons, context, and time can inform policy research in developmental psychology and can be used to support a causal…

  2. Progress toward risk informed regulation

    SciTech Connect

    Rogers, K.C.

    1997-01-01

    For the last several years, the NRC, with encouragement from the industry, has been moving in the direction of risk informed regulation. This is consistent with the regulatory principle of efficiency, formally adopted by the Nuclear Regulatory Commission in 1991, which requires that regulatory activities be consistent with the degree of risk reduction they achieve. Probabilistic risk analysis has become the tool of choice for selecting the best of several alternatives. Closely related to risk informed regulation is the development of performance based rules. Such rules focus on the end result to be achieved. They do not specify the process, but instead establish the goals to be reached and how the achievement of those goals is to be judged. The inspection and enforcement activity is based on whether or not the goals have been met. The author goes on to offer comments on the history of the development of this process and its probable development in the future. He also addresses some issues which must be resolved or at least acknowledged. The success of risk informed regulation ultimately depends on having sufficiently reliable data to allow quantification of regulatory alternatives in terms of relative risk. Perhaps the area of human reliability and organizational performance has the greatest potential for improvement in reactor safety. The ability to model human performance is significantly less developed that the ability to model mechanical or electrical systems. The move toward risk informed, performance based regulation provides an unusual, perhaps unique, opportunity to establish a more rational, more effective basis for regulation.

  3. Developmental regulation of the human antibody repertoire.

    PubMed

    Schroeder, H W; Mortari, F; Shiokawa, S; Kirkham, P M; Elgavish, R A; Bertrand, F E

    1995-09-29

    The ability to respond to antigen develops in a programmed fashion during ontogeny. In human, "fetal" immunoglobulin gene segment utilization appears biased towards a small set of evolutionarily conserved V gene segments. Many of these gene segments are also used in antibodies with antigen specificities that do not arise until after infancy. The human fetus primarily regulates the diversity of the antibody repertoire through control of the H (heavy) chain CDR 3, which is generated by VDJ joining and forms the center of the antigen-binding site. Molecular modeling suggests that limitations in the length and composition of fetal CDR 3 intervals result in antibodies that contain a relatively "flat" antigen-binding surface that could serve to maximize the number of different interactions possible between the antibody and potential antigens. We propose that these limitations in the sequence and structure of H chain CDR 3 contribute to the low affinity and multireactivity of fetal antibody repertoires. The specific mechanisms used to generate a restricted fetal repertoire appear to differ between human and mouse. Nevertheless, included in the final products of both human and mouse fetal B cells will be antibodies that are quite homologous in composition and structure. The precise role that these antibodies play in the development of immunocompetence remains to be elucidated.

  4. Developmentally Regulated Sphingolipid Synthesis in African Trypanosomes

    PubMed Central

    Sutterwala, Shaheen S.; Hsu, Fong Fu; Sevova, Elitza S.; Schwartz, Kevin J.; Zhang, Kai; Key, Phillip; Turk, John; Beverley, Stephen M.; Bangs, James D.

    2008-01-01

    Sphingolipids are essential components of eukaryotic membranes, and many unicellular eukaryotes, including kinetoplastid protozoa, are thought to synthesize exclusively inositol phosphorylceramide (IPC). Here we characterize sphingolipids from Trypanosoma brucei, and a trypanosome sphingolipid synthase gene family (TbSLS1-4) that is orthologous to Leishmania IPC synthase. Procyclic trypanosomes contain IPC, but also sphingomyelin, while surprisingly bloodstream stage parasites contain sphingomyelin and ethanolamine phosphorylceramide (EPC), but no detectable IPC. In vivo fluorescent ceramide labeling confirmed stage specific biosynthesis of both sphingomyelin and IPC. Expression of TbSLS4 in Leishmania resulted in production of sphingomyelin and EPC suggesting that the TbSLS gene family has bi-functional synthase activity. RNAi silencing of TbSLS1-4 in bloodstream trypanosomes led to rapid growth arrest and eventual cell death. Ceramide levels were increased >3-fold by silencing suggesting a toxic downstream effect mediated by this potent intracellular messenger. Topology predictions support a revised six transmembrane domain model for the kinetoplastid sphingolipid synthases consistent with the proposed mammalian SM synthase structure. This work reveals novel diversity and regulation in sphingolipid metabolism in this important group of human parasites. PMID:18699867

  5. Developmental programming of energy balance regulation: is physical activity more 'programmable' than food intake?

    PubMed

    Zhu, Shaoyu; Eclarinal, Jesse; Baker, Maria S; Li, Ge; Waterland, Robert A

    2016-02-01

    Extensive human and animal model data show that environmental influences during critical periods of prenatal and early postnatal development can cause persistent alterations in energy balance regulation. Although a potentially important factor in the worldwide obesity epidemic, the fundamental mechanisms underlying such developmental programming of energy balance are poorly understood, limiting our ability to intervene. Most studies of developmental programming of energy balance have focused on persistent alterations in the regulation of energy intake; energy expenditure has been relatively underemphasised. In particular, very few studies have evaluated developmental programming of physical activity. The aim of this review is to summarise recent evidence that early environment may have a profound impact on establishment of individual propensity for physical activity. Recently, we characterised two different mouse models of developmental programming of obesity; one models fetal growth restriction followed by catch-up growth, and the other models early postnatal overnutrition. In both studies, we observed alterations in body-weight regulation that persisted to adulthood, but no group differences in food intake. Rather, in both cases, programming of energy balance appeared to be due to persistent alterations in energy expenditure and spontaneous physical activity (SPA). These effects were stronger in female offspring. We are currently exploring the hypothesis that developmental programming of SPA occurs via induced sex-specific alterations in epigenetic regulation in the hypothalamus and other regions of the central nervous system. We will summarise the current progress towards testing this hypothesis. Early environmental influences on establishment of physical activity are likely an important factor in developmental programming of energy balance. Understanding the fundamental underlying mechanisms in appropriate animal models will help determine whether early life

  6. Developmental regulation of motor function: an uncharted sea.

    PubMed

    O'Donovan, M J

    1985-02-01

    The field of developmental neurobiology is entering a very exciting phase, in which the application of new techniques promises to lead to major advances in our understanding of basic developmental processes. There is a need to apply much of this new knowledge to problems of spinal cord and muscle development, about which little is known at present. An understanding of the development of muscle fiber types and the spinal circuitry controlling locomotion would have a major impact on fundamental problems in motor control and exercise physiology. Significant progress is likely to be made in these areas in the next few years, but only if researchers interested in motor control and related areas take an interest in development. Among the most immediate problems that need to be addressed are: the lineage analysis of spinal neurons; identification of the factors controlling neuron differentiation; identification of the molecular basis for directed axon growth; and analysis of the factors controlling network assembly in the spinal cord. In muscle development, an understanding of how fiber type proportions are generated would have great significance for disciplines related to motor performance. The interaction and exchange of ideas between developmental biologists and exercise scientists promises to accelerate understanding and progress in both fields of endeavor.

  7. School Readiness and Self-Regulation: A Developmental Psychobiological Approach

    PubMed Central

    Blair, Clancy; Raver, C. Cybele

    2015-01-01

    Research on the development of self-regulation in young children provides a unifying framework for the study of school readiness. Self-regulation abilities allow for engagement in learning activities and provide the foundation for adjustment to school. A focus on readiness as self-regulation does not supplant interest in the development of acquired ability, such as early knowledge of letters and numbers; it sets the stage for it. In this article, we review research and theory indicating that self-regulation and consequently school readiness are the product of integrated developmental processes at the biological and behavioral levels that are shaped by the contexts in which development is occurring. In doing so, we illustrate the idea that research on self-regulation powerfully highlights ways in which gaps in school readiness and later achievement are linked to poverty and social and economic inequality and points the way to effective approaches to counteract these conditions. PMID:25148852

  8. Endocytosis of cholera toxin by human enterocytes is developmentally regulated.

    PubMed

    Lu, Lei; Khan, Sameer; Lencer, Wayne; Walker, W Allan

    2005-08-01

    Many secretory diarrheas including cholera are more prevalent and fulminant in young infants than in older children and adults. Cholera toxin (CT) elicits a cAMP-dependent chloride secretory response in intestinal epithelia, which accounts for the fundamental pathogenesis of this toxigenic diarrhea. We have previously reported that the action of this bacterial enterotoxin is excessive in immature enterocytes and under developmental regulation. In this study, we tested the hypothesis that enhanced endocytosis by immature human enterocytes may, in part, account for the excessive secretory response to CT noted in the immature intestine and that enterocyte endocytosis of CT is developmentally regulated. To test this hypothesis, we used specific inhibitors to define endocytic pathways in mature and immature cell lines. We showed that internalization of CT in adult enterocytes is less and occurs via the caveolae/raft-mediated pathway in contrast to an enhanced immature human enterocyte CT uptake that occurs via a clathrin pathway. We also present evidence that this clathrin pathway is developmentally regulated as demonstrated by its response to corticosteroids, a known maturation factor that causes a decreased CT endocytosis by this pathway.

  9. Callose homeostasis at plasmodesmata: molecular regulators and developmental relevance

    PubMed Central

    De Storme, Nico; Geelen, Danny

    2014-01-01

    Plasmodesmata are membrane-lined channels that are located in the plant cell wall and that physically interconnect the cytoplasm and the endoplasmic reticulum (ER) of adjacent cells. Operating as controllable gates, plasmodesmata regulate the symplastic trafficking of micro- and macromolecules, such as endogenous proteins [transcription factors (TFs)] and RNA-based signals (mRNA, siRNA, etc.), hence mediating direct cell-to-cell communication and long distance signaling. Besides this physiological role, plasmodesmata also form gateways through which viral genomes can pass, largely facilitating the pernicious spread of viral infections. Plasmodesmatal trafficking is either passive (e.g., diffusion) or active and responses both to developmental and environmental stimuli. In general, plasmodesmatal conductivity is regulated by the controlled build-up of callose at the plasmodesmatal neck, largely mediated by the antagonistic action of callose synthases (CalSs) and β-1,3-glucanases. Here, in this theory and hypothesis paper, we outline the importance of callose metabolism in PD SEL control, and highlight the main molecular factors involved. In addition, we also review other proteins that regulate symplastic PD transport, both in a developmental and stress-responsive framework, and discuss on their putative role in the modulation of PD callose turn-over. Finally, we hypothesize on the role of structural sterols in the regulation of (PD) callose deposition and outline putative mechanisms by which this regulation may occur. PMID:24795733

  10. Developmental regulation of fear learning and anxiety behavior by endocannabinoids

    PubMed Central

    Lee, Tiffany T.-Y.; Hill, Matthew N.; Lee, Francis S.

    2015-01-01

    The developing brain undergoes substantial maturation into adulthood and the development of specific neural structures occurs on differing timelines. Transient imbalances between developmental trajectories of corticolimbic structures, which are known to contribute to regulation over fear learning and anxiety, can leave an individual susceptible to mental illness, particularly anxiety disorders. There is a substantial body of literature indicating that the endocannabinoid system critically regulates stress responsivity and emotional behavior throughout the life span, making this system a novel therapeutic target for stress- and anxiety-related disorders. During early life and adolescence, corticolimbic endocannabinoid signaling changes dynamically and coincides with different sensitive periods of fear learning, suggesting that endocannabinoid signaling underlies age-specific fear learning responses. Moreover, perturbations to these normative fluctuations in corticolimbic endocannabinoid signaling, such as stress or cannabinoid exposure, could serve as a neural substrate contributing to alterations to the normative developmental trajectory of neural structures governing emotional behavior and fear learning. In this review, we first introduce the components of the endocannabinoid system and discuss clinical and rodent models demonstrating endocannabinoid regulation of fear learning and anxiety in adulthood. Next, we highlight distinct fear learning and regulation profiles throughout development and discuss the ontogeny of the endocannabinoid system in the central nervous system, and models of pharmacological augmentation of endocannabinoid signaling during development in the context of fear learning and anxiety. PMID:26419643

  11. Developmental regulation of fear learning and anxiety behavior by endocannabinoids.

    PubMed

    Lee, T T-Y; Hill, M N; Lee, F S

    2016-01-01

    The developing brain undergoes substantial maturation into adulthood and the development of specific neural structures occurs on differing timelines. Transient imbalances between developmental trajectories of corticolimbic structures, which are known to contribute to regulation over fear learning and anxiety, can leave an individual susceptible to mental illness, particularly anxiety disorders. There is a substantial body of literature indicating that the endocannabinoid (eCB) system critically regulates stress responsivity and emotional behavior throughout the life span, making this system a novel therapeutic target for stress- and anxiety-related disorders. During early life and adolescence, corticolimbic eCB signaling changes dynamically and coincides with different sensitive periods of fear learning, suggesting that eCB signaling underlies age-specific fear learning responses. Moreover, perturbations to these normative fluctuations in corticolimbic eCB signaling, such as stress or cannabinoid exposure, could serve as a neural substrate contributing to alterations to the normative developmental trajectory of neural structures governing emotional behavior and fear learning. In this review, we first introduce the components of the eCB system and discuss clinical and rodent models showing eCB regulation of fear learning and anxiety in adulthood. Next, we highlight distinct fear learning and regulation profiles throughout development and discuss the ontogeny of the eCB system in the central nervous system, and models of pharmacological augmentation of eCB signaling during development in the context of fear learning and anxiety.

  12. Regulation of priority carcinogens and reproductive or developmental toxicants

    SciTech Connect

    Hooper, K.; LaDou, J.; Rosenbaum, J.S.; Book, S.A. )

    1992-01-01

    In California, 370 carcinogens and 112 reproductive/developmental toxicants have been identified as a result of the State's Safe Drinking Water and Toxic Enforcement Act of 1986. They include pesticides, solvents, metals, industrial intermediates, environmental mixtures, and reactive agents. Occupational, environmental, and consumer product exposures that involve these agents are regulated under the Act. At levels of concern, businesses must provide warnings for and limit discharges of those chemicals. The lists of chemicals were compiled following systematic review of published data, including technical reports from the U.S. Public Health Service--National Toxicology Program (NTP), and evaluation of recommendations from authoritative bodies such as the International Agency for Research on Cancer (IARC) and the U.S. Environmental Protection Agency (USEPA). Given the large number of chemicals that are carcinogens or reproductive/developmental toxicants, regulatory concerns should focus on those that have high potential for human exposure, e.g., widely distributed or easily absorbed solvents, metals, environmental mixtures, or reactive agents. In this paper, we present a list of 33 potential priority carcinogens and reproductive/developmental toxicants, including alcoholic beverages, asbestos, benzene, chlorinated solvents, formaldehyde, glycol ethers, lead, tobacco smoke, and toluene.

  13. DNA Methylation is Developmentally Regulated for Genes Essential for Cardiogenesis

    PubMed Central

    Chamberlain, Alyssa A.; Lin, Mingyan; Lister, Rolanda L.; Maslov, Alex A.; Wang, Yidong; Suzuki, Masako; Wu, Bingruo; Greally, John M.; Zheng, Deyou; Zhou, Bin

    2014-01-01

    Background DNA methylation is a major epigenetic mechanism altering gene expression in development and disease. However, its role in the regulation of gene expression during heart development is incompletely understood. The aim of this study is to reveal DNA methylation in mouse embryonic hearts and its role in regulating gene expression during heart development. Methods and Results We performed the genome‐wide DNA methylation profiling of mouse embryonic hearts using methyl‐sensitive, tiny fragment enrichment/massively parallel sequencing to determine methylation levels at ACGT sites. The results showed that while global methylation of 1.64 million ACGT sites in developing hearts remains stable between embryonic day (E) 11.5 and E14.5, a small fraction (2901) of them exhibit differential methylation. Gene Ontology analysis revealed that these sites are enriched at genes involved in heart development. Quantitative real‐time PCR analysis of 350 genes with differential DNA methylation showed that the expression of 181 genes is developmentally regulated, and 79 genes have correlative changes between methylation and expression, including hyaluronan synthase 2 (Has2). Required for heart valve formation, Has2 expression in the developing heart valves is downregulated at E14.5, accompanied with increased DNA methylation in its enhancer. Genetic knockout further showed that the downregulation of Has2 expression is dependent on DNA methyltransferase 3b, which is co‐expressed with Has2 in the forming heart valve region, indicating that the DNA methylation change may contribute to the Has2 enhancer's regulating function. Conclusions DNA methylation is developmentally regulated for genes essential to heart development, and abnormal DNA methylation may contribute to congenital heart disease. PMID:24947998

  14. Chronic Disease and Perceived Developmental Progression in Adolescence.

    ERIC Educational Resources Information Center

    Seiffge-Krenke, Inge

    1998-01-01

    Examined whether chronic illness causes delays in adolescents' perceived developmental status, using annually-completed questionnaires from insulin-dependent and healthy adolescents. Found that, in first year of study, diabetic adolescents reported delays in physical maturity and an independent lifestyle compared with healthy peers. Overall…

  15. Developmental regulation of key gluconeogenic molecules in nonhuman primates

    PubMed Central

    McGill‐Vargas, Lisa L.; Johnson‐Pais, Teresa; Johnson, Marney C.; Blanco, Cynthia L.

    2014-01-01

    Abstract Aberrant glucose regulation is common in preterm and full‐term neonates leading to short and long‐term morbidity/mortality; however, glucose metabolism in this population is understudied. The aim of this study was to investigate developmental differences in hepatic gluconeogenic pathways in fetal/newborn baboons. Fifteen fetal baboons were delivered at 125 day (d) gestational age (GA), 140d GA, and 175d GA (term = 185d GA) via cesarean section and sacrificed at birth. Term and healthy adult baboons were used as controls. Protein content and gene expression of key hepatic gluconeogenic molecules were measured: cytosolic and mitochondrial phosphoenolpyruvate carboxykinase (PEPCK‐C and PEPCK‐M), glucose‐6‐phosphatase‐alpha (G6Pase‐α), G6Pase‐β, fructose‐1,6‐bisphosphatase (FBPase), and forkhead box‐O1 (FOXO1). Protein content of PEPCK‐M increased with advancing gestation in fetal baboons (9.6 fold increase from 125d GA to 175d GA, P < 0.001). PEPCK‐C gene expression was consistent with these developmental differences. Phosphorylation of FOXO1 was significantly lower in preterm fetal baboons compared to adults, and gene expression of FOXO1 was lower in all neonates when compared to adults (10% and 62% of adults respectively, P < 0.05). The FOXO1 target gene G6Pase expression was higher in preterm animals compared to term animals. No significant differences were found in G6Pase‐α, G6Pase‐β, FOXO1, and FBPase during fetal development. In conclusion, significant developmental differences are found in hepatic gluconeogenic molecules in fetal and neonatal baboons, which may impact the responses to insulin during the neonatal period. Further studies under insulin‐stimulated conditions are required to understand the physiologic impact of these maturational differences. PMID:25524279

  16. Developmental regulation of nicotinic synapses on cochlear inner hair cells.

    PubMed

    Katz, Eleonora; Elgoyhen, Ana Belén; Gómez-Casati, María E; Knipper, Marlies; Vetter, Douglas E; Fuchs, Paul A; Glowatzki, Elisabeth

    2004-09-08

    In the mature cochlea, inner hair cells (IHCs) transduce acoustic signals into receptor potentials, communicating to the brain by synaptic contacts with afferent fibers. Before the onset of hearing, a transient efferent innervation is found on IHCs, mediated by a nicotinic cholinergic receptor that may contain both alpha9 and alpha10 subunits. Calcium influx through that receptor activates calcium-dependent (SK2-containing) potassium channels. This inhibitory synapse is thought to disappear after the onset of hearing [after postnatal day 12 (P12)]. We documented this developmental transition using whole-cell recordings from IHCs in apical turns of the rat organ of Corti. Acetylcholine elicited ionic currents in 88-100% of IHCs between P3 and P14, but in only 1 of 11 IHCs at P16-P22. Potassium depolarization of efferent terminals caused IPSCs in 67% of IHCs at P3, in 100% at P7-P9, in 93% at P10-P12, but in only 40% at P13-P14 and in none of the IHCs tested between P16 and P22. Earlier work had shown by in situ hybridization that alpha9 mRNA is expressed in adult IHCs but that alpha10 mRNA disappears after the onset of hearing. In the present study, antibodies to alpha10 and to the associated calcium-dependent (SK2) potassium channel showed a similar developmental loss. The correlated expression of these gene products with functional innervation suggests that Alpha10 and SK2, but not Alpha9, are regulated by synaptic activity. Furthermore, this developmental knock-out of alpha10, but not alpha9, supports the hypothesis that functional nicotinic acetylcholine receptors in hair cells are heteromers containing both these subunits.

  17. Torso-like functions independently of Torso to regulate Drosophila growth and developmental timing.

    PubMed

    Johnson, Travis K; Crossman, Tova; Foote, Karyn A; Henstridge, Michelle A; Saligari, Melissa J; Forbes Beadle, Lauren; Herr, Anabel; Whisstock, James C; Warr, Coral G

    2013-09-03

    Activation of the Drosophila receptor tyrosine kinase Torso (Tor) only at the termini of the embryo is achieved by the localized expression of the maternal gene Torso-like (Tsl). Tor has a second function in the prothoracic gland as the receptor for prothoracicotropic hormone (PTTH) that initiates metamorphosis. Consistent with the function of Tor in this tissue, Tsl also localizes to the prothoracic gland and influences developmental timing. Despite these commonalities, in our studies of Tsl we unexpectedly found that tsl and tor have opposing effects on body size; tsl null mutants are smaller than normal, rather than larger as would be expected if the PTTH/Tor pathway was disrupted. We further found that whereas both genes regulate developmental timing, tsl does so independently of tor. Although tsl null mutants exhibit a similar length delay in time to pupariation to tor mutants, in tsl:tor double mutants this delay is strikingly enhanced. Thus, loss of tsl is additive rather than epistatic to loss of tor. We also find that phenotypes generated by ectopic PTTH expression are independent of tsl. Finally, we show that a modified form of tsl that can rescue developmental timing cannot rescue terminal patterning, indicating that Tsl can function via distinct mechanisms in different contexts. We conclude that Tsl is not just a specialized cue for Torso signaling but also acts independently of PTTH/Tor in the control of body size and the timing of developmental progression. These data highlight surprisingly diverse developmental functions for this sole Drosophila member of the perforin-like superfamily.

  18. Cellular manganese content is developmentally regulated in human dopaminergic neurons

    PubMed Central

    Kumar, Kevin K.; Lowe, Jr., Edward W.; Aboud, Asad A.; Neely, M. Diana; Redha, Rey; Bauer, Joshua A.; Odak, Mihir; Weaver, C. David; Meiler, Jens; Aschner, Michael; Bowman, Aaron B.

    2014-01-01

    Manganese (Mn) is both an essential biological cofactor and neurotoxicant. Disruption of Mn biology in the basal ganglia has been implicated in the pathogenesis of neurodegenerative disorders, such as parkinsonism and Huntington's disease. Handling of other essential metals (e.g. iron and zinc) occurs via complex intracellular signaling networks that link metal detection and transport systems. However, beyond several non-selective transporters, little is known about the intracellular processes regulating neuronal Mn homeostasis. We hypothesized that small molecules that modulate intracellular Mn could provide insight into cell-level Mn regulatory mechanisms. We performed a high throughput screen of 40,167 small molecules for modifiers of cellular Mn content in a mouse striatal neuron cell line. Following stringent validation assays and chemical informatics, we obtained a chemical ‘toolbox' of 41 small molecules with diverse structure-activity relationships that can alter intracellular Mn levels under biologically relevant Mn exposures. We utilized this toolbox to test for differential regulation of Mn handling in human floor-plate lineage dopaminergic neurons, a lineage especially vulnerable to environmental Mn exposure. We report differential Mn accumulation between developmental stages and stage-specific differences in the Mn-altering activity of individual small molecules. This work demonstrates cell-level regulation of Mn content across neuronal differentiation. PMID:25348053

  19. Cellular manganese content is developmentally regulated in human dopaminergic neurons

    NASA Astrophysics Data System (ADS)

    Kumar, Kevin K.; Lowe, Edward W., Jr.; Aboud, Asad A.; Neely, M. Diana; Redha, Rey; Bauer, Joshua A.; Odak, Mihir; Weaver, C. David; Meiler, Jens; Aschner, Michael; Bowman, Aaron B.

    2014-10-01

    Manganese (Mn) is both an essential biological cofactor and neurotoxicant. Disruption of Mn biology in the basal ganglia has been implicated in the pathogenesis of neurodegenerative disorders, such as parkinsonism and Huntington's disease. Handling of other essential metals (e.g. iron and zinc) occurs via complex intracellular signaling networks that link metal detection and transport systems. However, beyond several non-selective transporters, little is known about the intracellular processes regulating neuronal Mn homeostasis. We hypothesized that small molecules that modulate intracellular Mn could provide insight into cell-level Mn regulatory mechanisms. We performed a high throughput screen of 40,167 small molecules for modifiers of cellular Mn content in a mouse striatal neuron cell line. Following stringent validation assays and chemical informatics, we obtained a chemical `toolbox' of 41 small molecules with diverse structure-activity relationships that can alter intracellular Mn levels under biologically relevant Mn exposures. We utilized this toolbox to test for differential regulation of Mn handling in human floor-plate lineage dopaminergic neurons, a lineage especially vulnerable to environmental Mn exposure. We report differential Mn accumulation between developmental stages and stage-specific differences in the Mn-altering activity of individual small molecules. This work demonstrates cell-level regulation of Mn content across neuronal differentiation.

  20. Nucleus downscaling in mouse embryos is regulated by cooperative developmental and geometric programs

    PubMed Central

    Tsichlaki, Elina; FitzHarris, Greg

    2016-01-01

    Maintaining appropriate nucleus size is important for cell health, but the mechanisms by which this is achieved are poorly understood. Controlling nucleus size is a particular challenge in early development, where the nucleus must downscale in size with progressive reductive cell divisions. Here we use live and fixed imaging, micromanipulation approaches, and small molecule analyses during preimplantation mouse development to probe the mechanisms by which nucleus size is determined. We find a close correlation between cell and nuclear size at any given developmental stage, and show that experimental cytoplasmic reduction can alter nuclear size, together indicating that cell size helps dictate nuclear proportions. Additionally, however, by creating embryos with over-sized blastomeres we present evidence of a developmental program that drives nuclear downscaling independently of cell size. We show that this developmental program does not correspond with nuclear import rates, but provide evidence that PKC activity may contribute to this mechanism. We propose a model in which nuclear size regulation during early development is a multi-mode process wherein nucleus size is set by cytoplasmic factors, and fine-tuned on a cell-by-cell basis according to cell size. PMID:27320842

  1. The developmentally regulated avian protein IFAPa-400 is transitin.

    PubMed

    Ma, X; Charron, F; Cole, G J; Savard, P E; Vincent, M

    1998-07-01

    Transitin and IFAPa-400 are developmentally regulated high M(r) proteins expressed transiently in early chick embryogenesis. Both are associated with radially oriented fibers in the developing CNS and with various neural and myogenic tissues before their down-regulation at later stages. Previous studies have shown that IFAPa-400 colocalized and copurified with intermediate filament proteins and recent molecular cloning has indicated that transitin is a member of this family of cytoskeletal proteins. Here, we provide evidence that IFAPa-400 and transitin are the same protein. The sequence of a composite cDNA corresponding to more than 700 amino acids of IFAPa-400 carboxy-terminal extremity is identical to that of transitin. Both proteins exhibit identical apparent M(r) and isoelectric point. Immunopurified IFAPa-400 reacts with different antibodies to transitin and vice-versa. The patterns of expression of both proteins show a perfect coincidence at the tissue level. At the subcellular level, most antibodies to IFAPa-400/transitin decorate a typical intermediate filament network. However, monoclonal antibody A2B11, at the origin of transitin identification, exhibits a staining more typical of a cortical component, suggesting that different populations of transitin exist within the cell.

  2. Aphid polyphenisms: trans-generational developmental regulation through viviparity

    PubMed Central

    Ogawa, Kota; Miura, Toru

    2013-01-01

    Polyphenism, in which multiple discrete phenotypes develop from a single genotype, is considered to have contributed to the evolutionary success of aphids. Of the various polyphenisms observed in the complex life cycle of aphids, the reproductive and wing polyphenisms seen in most aphid species are conspicuous. In reproductive polyphenism, the reproductive modes can change between viviparous parthenogenesis and sexual reproduction in response to the photoperiod. Under short-day conditions in autumn, sexual morphs (males and oviparous females) are produced parthenogenetically. Winged polyphenism is observed in viviparous generations during summer, when winged or wingless (flightless) aphids are produced depending on a variety of environmental conditions (e.g., density, predators). Here, we review the physiological mechanisms underlying reproductive and wing polyphenism in aphids. In reproductive polyphenism, morph determination (male, oviparous or viviparous female) within mother aphids is regulated by juvenile hormone (JH) titers in the mothers. In wing polyphenism, although JH is considered to play an important role in phenotype determination (winged or wingless), the role is still controversial. In both cases, the acquisition of viviparity in Aphididae is considered to be the basis for maternal regulation of these polyphenisms, and through which environmental cues can be transferred to developing embryos through the physiological state of the mother. Although the mechanisms by which mothers alter the developmental programs of their progeny have not yet been clarified, continued developments in molecular biology will likely unravel these questions. PMID:24478714

  3. Developmental progress and current status of the Animal QTLdb

    PubMed Central

    Hu, Zhi-Liang; Park, Carissa A.; Reecy, James M.

    2016-01-01

    The Animal QTL Database (QTLdb; http://www.animalgenome.org/QTLdb) has undergone dramatic growth in recent years in terms of new data curated, data downloads and new functions and tools. We have focused our development efforts to cope with challenges arising from rapid growth of newly published data and end users’ data demands, and to optimize data retrieval and analysis to facilitate users’ research. Evidenced by the 27 releases in the past 11 years, the growth of the QTLdb has been phenomenal. Here we report our recent progress which is highlighted by addition of one new species, four new data types, four new user tools, a new API tool set, numerous new functions and capabilities added to the curator tool set, expansion of our data alliance partners and more than 20 other improvements. In this paper we present a summary of our progress to date and an outlook regarding future directions. PMID:26602686

  4. Embryonic developmental progression in lake trout (Salvelinus namaycush) (Walbaum, 1792) and its relation to lake temperature

    USGS Publications Warehouse

    Allen, Jeffrey D.; Walker, Glenn K.; Adams, Jean V.; Nichols, S. Jerrine; Edsall, Carol C.

    2005-01-01

    Developmental progression of lake trout (Salvelinus namaycush) embryos was examined with light and scanning electron microscopy. From this examination, key developmental stages were described in detail. The key developmental stages were then applied to individual lake trout egg lots incubated in constant temperatures of 2, 4, 6, 8, and 10°C. We used Belehradek's, Thermodynamic, and Power models, and also developed the Zero model to determine stage specific developmental rates of lake trout eggs for each background temperature. From the models, hatch dates and staging were predicted for temperature regimes from Lake Superior (1990–91) and Lake Huron (1996–97). Based on the existing lake temperature data and the observed spawning dates, the Zero and the Power models predict that post peak spawning may contribute significantly to overall recruitment success for these years.

  5. E2F and its developmental regulation in Xenopus laevis.

    PubMed Central

    Philpott, A; Friend, S H

    1994-01-01

    The transcription factor E2F has been implicated in cell cycle control by virtue of its association with cyclins, cyclin-dependent kinases, and pRb-related tumor suppressor gene products. Eggs and embryos from the frog Xenopus laevis have been used to investigate the characteristics of E2F-like molecules in the Xenopus cell cycle and throughout early development. We find multiple E2F species in Xenopus eggs, at least one of which is modified by phosphorylation. The vast majority of E2F remains in the free form throughout the very early embryonic cell cycle, and it also remains predominantly free until some time after the mid-blastula transition, the onset of zygotic transcription. At this time, E2F complexes significantly to pRb but not to cdk2, although cdk2 binding is found in tissue culture cells from a very advanced stage in embryogenesis. This suggests that the complexing of E2F to cyclins, cyclin-dependent kinases, and tumor suppressor gene products may be controlled separately in early Xenopus development. Thus, the association of E2F with other molecules may not result solely from processes affecting cell cycle progression but may also reflect developmental and differentiation cues. Images PMID:8007993

  6. Developmental Progression of Looking and Reaching Performance on the A-Not-B Task

    ERIC Educational Resources Information Center

    Cuevas, Kimberly; Bell, Martha Ann

    2010-01-01

    From a neuropsychological perspective, the cognitive skills of working memory, inhibition, and attention and the maturation of the frontal lobe are requisites for successful A-not-B performance on both the looking and reaching versions of the task. This study used a longitudinal design to examine the developmental progression of infants'…

  7. Developmental regulation of nicotinic acetylcholine receptors within midbrain dopamine neurons

    PubMed Central

    Azam, Layla; Chen, Yiling; Leslie, Frances M.

    2007-01-01

    We have combined anatomical and functional methodologies to provide a comprehensive analysis of the properties of nicotinic acetylcholine receptors (nAChRs) on developing dopamine (DA) neurons. Double-labeling in situ hybridization was used to examine the expression of nAChR subunit mRNAs within developing midbrain DA neurons. As brain maturation progressed there was a change in the pattern of subunit mRNA expression within DA neurons, such that α3 and α4 subunits declined and α6 mRNA increased. Although there were strong similarities in subunit mRNA expression in substantia nigra (SNc) and ventral tegmental area (VTA), there was higher expression of α4 mRNA in SNc than VTA at gestational day (G)15, and of α5, α6 and β3 mRNAs during postnatal development. Using a superfusion neurotransmitter release paradigm to functionally characterize nicotine-stimulated release of [3H]DA from striatal slices, the properties of the nAChRs on DA terminals were also found to change with age. Functional nAChRs were detected on striatal terminals at G18. There was a decrease in maximal release in the first postnatal week, followed by an increase in nicotine efficacy and potency during the second and third postnatal weeks. In the transition from adolescence (postnatal days (P) 30 and 40) to adulthood, there was a complex pattern of functional maturation of nAChRs in ventral, but not dorsal, striatum. In males, but not females, there were significant changes in both nicotine potency and efficacy during this developmental period. These findings suggest that nAChRs may play critical functional roles throughout DA neuronal maturation. PMID:17197101

  8. Regulated lysosomal exocytosis mediates cancer progression

    PubMed Central

    Machado, Eda; White-Gilbertson, Shai; van de Vlekkert, Diantha; Janke, Laura; Moshiach, Simon; Campos, Yvan; Finkelstein, David; Gomero, Elida; Mosca, Rosario; Qiu, Xiaohui; Morton, Christopher L.; Annunziata, Ida; d’Azzo, Alessandra

    2015-01-01

    Understanding how tumor cells transition to an invasive and drug-resistant phenotype is central to cancer biology, but the mechanisms underlying this transition remain unclear. We show that sarcomas gain these malignant traits by inducing lysosomal exocytosis, a ubiquitous physiological process. During lysosomal exocytosis, the movement of exocytic lysosomes along the cytoskeleton and their docking at the plasma membrane involve LAMP1, a sialylated membrane glycoprotein and target of the sialidase NEU1. Cleavage of LAMP1 sialic acids by NEU1 limits the extent of lysosomal exocytosis. We found that by down-regulation of NEU1 and accumulation of oversialylated LAMP1, tumor cells exacerbate lysosomal exocytosis of soluble hydrolases and exosomes. This facilitates matrix invasion and propagation of invasive signals, and purging of lysosomotropic chemotherapeutics. In Arf−⁄− mice, Neu1 haploinsufficiency fostered the development of invasive, pleomorphic sarcomas, expressing epithelial and mesenchymal markers, and lysosomal exocytosis effectors, LAMP1 and Myosin-11. These features are analogous to those of metastatic, pleomorphic human sarcomas, where low NEU1 levels correlate with high expression of lysosomal exocytosis markers. In a therapeutic proof of principle, we demonstrate that inhibiting lysosomal exocytosis reversed invasiveness and chemoresistance in aggressive sarcoma cells. Thus, we reveal that this unconventional, lysosome-regulated pathway plays a primary role in tumor progression and chemoresistance. PMID:26824057

  9. Inflammatory and Immune Activation in Intestinal Myofibroblasts Is Developmentally Regulated

    PubMed Central

    Zawahir, Sharmila; Li, Guanghui; Banerjee, Aditi; Shiu, Jessica; Blanchard, Thomas G.

    2015-01-01

    We previously demonstrated that intestinal myofibroblasts from immature tissue produce excessive IL-8 in response to Escherichia coli lipopolysaccharide (LPS) compared to cells from mature tissue. However, it is unknown whether other cytokines and TLR agonists contribute to this developmentally regulated response. The aim of this study was to further characterize differences in inflammatory signaling in human primary intestinal fibroblasts from fetal (FIF) and infant (IIF) tissue and examine their potential to activate the adaptive immune response in vitro. Cytokine profiles of LPS-stimulated FIF and IIF were assessed by cytokine profile array. IL-8, IL-6, and IL-10 production in response to TLR2, TLR2/6, TLR4, and TLR5 agonists was determined by quantitative ELISA. The potential of activated myofibroblasts to activate adaptive immunity was determined by measuring surface class II MHC expression using flow cytometry. LPS-stimulated FIF produced a distinct proinflammatory cytokine profile consisting of MCP-1, GRO-alpha, IL-6, and IL-8 expression. FIF produced significant IL-8 and IL-6 in response to TLR4 agonist. IIF produced significant levels of IL-8 and IL-6 in the presence of TLR5 and TLR2 agonists. IFN-γ-treated FIF expressed greater HLA-DR levels compared to unstimulated controls and IFN-γ- and LPS-treated IIF. Activated FIF produce a more diverse inflammatory cytokine profile and greater levels of IL-8 and IL-6 in response to TLR4 stimulation compared to IIF. FIF express class II MHC proteins associated with activation of the adaptive immune response. These data suggest that FIF may contribute to bacterial-associated gut inflammation in the immature intestine. PMID:26101946

  10. Developmental regulation of human truncated nerve growth factor receptor

    SciTech Connect

    DiStefano, P.S.; Clagett-Dame, M.; Chelsea, D.M.; Loy, R. )

    1991-01-01

    Monoclonal antibodies (designated XIF1 and IIIG5) recognizing distinct epitopes of the human truncated nerve growth factor receptor (NGF-Rt) were used in a two-site radiometric immunosorbent assay to monitor levels of NGF-Rt in human urine as a function of age. Urine samples were collected from 70 neurologically normal subjects ranging in age from 1 month to 68 years. By using this sensitive two-site radiometric immunosorbent assay, NGF-Rt levels were found to be highest in urine from 1-month old subjects. By 2.5 months, NGF-Rt values were half of those seen at 1 month and decreased more gradually between 0.5 and 15 years. Between 15 and 68 years, urine NGF-Rt levels were relatively constant at 5% of 1-month values. No evidence for diurnal variation of adult NGF-Rt was apparent. Pregnant women in their third trimester showed significantly elevated urine NGF-Rt values compared with age-matched normals. Affinity labeling of NGF-Rt with 125I-NGF followed by immunoprecipitation with ME20.4-IgG and gel autoradiography indicated that neonatal urine contained high amounts of truncated receptor (Mr = 50 kd); decreasingly lower amounts of NGF-Rt were observed on gel autoradiograms with development, indicating that the two-site radiometric immunosorbent assay correlated well with the affinity labeling technique for measuring NGF-Rt. NGF-Rt in urines from 1-month-old and 36-year-old subjects showed no differences in affinities for NGF or for the monoclonal antibody IIIG5. These data show that NGF-Rt is developmentally regulated in human urine, and are discussed in relation to the development and maturation of the peripheral nervous system.

  11. Checks and Balances: Rpd3 Issues Executive Orders in Developmental Enhancer Regulation.

    PubMed

    Martire, Sara; Banaszynski, Laura

    2017-02-27

    Stem cells use poised enhancers of developmental regulators to maintain pluripotency and for subsequent activation in differentiating progeny. In this issue of Developmental Cell, Janssens et al. (2017) demonstrate that the erm enhancer is maintained in a poised state in neural stem cells by the histone deacetylase Hdac1/Rpd3.

  12. A national Delphi to determine developmental progression of quality and safety competencies in nursing education.

    PubMed

    Barton, Amy J; Armstrong, Gail; Preheim, Gayle; Gelmon, Sherril B; Andrus, Lynne C

    2009-01-01

    Quality and Safety Education for Nurses (QSEN) faculty outlined 6 competency domains: patient-centered care, teamwork and collaboration, evidence-based practice, quality improvement, safety, and informatics. In this study, 18 subject matter experts participated in a web-based modified Delphi survey between October 2008 and February 2009 to determine whether there was consensus on the developmental progression of knowledge, skill, and attitude elements within the QSEN competencies. Support for creation of curricular threads to facilitate student progressive achievement of the QSEN competencies was validated. Competency development related to the individual patient was emphasized early in the curriculum, whereas teams and systems were emphasized later. Complex concepts such as teamwork and collaboration, evidence-based practice, quality improvement, and informatics were emphasized in advanced courses. Experts outlined a developmental approach in curriculum design, which would potentially encourage practice, reinforcement of learning, and recognition of context of care.

  13. In Vitro Developmental Toxicology Screens: A Report on the Progress of the Methodology and Future Applications.

    PubMed

    Zhang, Cindy; Ball, Jonathan; Panzica-Kelly, Julie; Augustine-Rauch, Karen

    2016-04-18

    There has been increasing focus on generation and assessment of in vitro developmental toxicology models for assessing teratogenic liability of chemicals. The driver for this focus has been to find reliable in vitro assays that will reduce or replace the use of in vivo tests for assessing teratogenicity. Such efforts may be eventually applied in testing pharmaceutical agents where a developmental toxicology assay or battery of assays may be incorporated into regulatory testing to replace one of the two species currently used in teratogenic assessment. Such assays may be eventually applied in testing a broader spectrum of chemicals, supporting efforts aligned with Tox21 strategies and responding to REACH legislation. This review describes the developmental toxicology assays that are of focus in these assessments: rodent whole embryo culture, zebrafish embryo assays, and embryonic stem cell assays. Progress on assay development as well as future directions of how these assays are envisioned to be applied for broader safety testing of chemicals are discussed. Altogether, the developmental model systems described in this review provide rich biological systems that can be utilized in better understanding teratogenic mechanisms of action of chemotypes and are promising in providing proactive safety assessment related to developmental toxicity. Continual advancements in refining/optimizing these in vitro assays are anticipated to provide a robust data set to provide thoughtful assessment of how whole animal teratogenicity evaluations can be reduced/refined in the future.

  14. Unliganded thyroid hormone receptor α regulates developmental timing via gene repression in Xenopus tropicalis.

    PubMed

    Choi, Jinyoung; Suzuki, Ken-Ichi T; Sakuma, Tetsushi; Shewade, Leena; Yamamoto, Takashi; Buchholz, Daniel R

    2015-02-01

    Thyroid hormone (TH) receptor (TR) expression begins early in development in all vertebrates when circulating TH levels are absent or minimal, yet few developmental roles for unliganded TRs have been established. Unliganded TRs are expected to repress TH-response genes, increase tissue responsivity to TH, and regulate the timing of developmental events. Here we examined the role of unliganded TRα in gene repression and development in Xenopus tropicalis. We used transcription activator-like effector nuclease gene disruption technology to generate founder animals with mutations in the TRα gene and bred them to produce F1 offspring with a normal phenotype and a mutant phenotype, characterized by precocious hind limb development. Offspring with a normal phenotype had zero or one disrupted TRα alleles, and tadpoles with the mutant hind limb phenotype had two truncated TRα alleles with frame shift mutations between the two zinc fingers followed by 40-50 mutant amino acids and then an out-of-frame stop codon. We examined TH-response gene expression and early larval development with and without exogenous TH in F1 offspring. As hypothesized, mutant phenotype tadpoles had increased expression of TH-response genes in the absence of TH and impaired induction of these same genes after exogenous TH treatment, compared with normal phenotype animals. Also, mutant hind limb phenotype animals had reduced hind limb and gill responsivity to exogenous TH. Similar results in methimazole-treated tadpoles showed that increased TH-response gene expression and precocious development were not due to early production of TH. These results indicate that unliganded TRα delays developmental progression by repressing TH-response genes.

  15. Revisiting a Progressive Pedagogy. The Developmental-Interaction Approach. SUNY Series, Early Childhood Education: Inquiries and Insights.

    ERIC Educational Resources Information Center

    Nager, Nancy, Ed.; Shapiro, Edna K., Ed.

    This book reviews the history of the developmental-interactive approach, a formulation rooted in developmental psychology and educational practice, progressively informing educational thinking since the early 20th century. The book describes and analyzes key assumptions and assesses the compatibility of new theoretical approaches, focuses on…

  16. DRG2 Regulates G2/M Progression via the Cyclin B1-Cdk1 Complex

    PubMed Central

    Jang, Soo Hwa; Kim, Ah-Ram; Park, Neung-Hwa; Park, Jeong Woo; Han, In-Seob

    2016-01-01

    Developmentally regulated GTP-binding protein 2 (DRG2) plays an important role in cell growth. Here we explored the linkage between DRG2 and G2/M phase checkpoint function in cell cycle progression. We observed that knockdown of DRG2 in HeLa cells affected growth in a wound-healing assay, and tumorigenicity in nude mice xenografts. Flow cytometry assays and [3H] incorporation assays indicated that G2/M phase arrest was responsible for the decreased proliferation of these cells. Knockdown of DRG2 elicited down-regulation of the major mitotic promoting factor, the cyclin B1/Cdk1 complex, but up-regulation of the cell cycle arresting proteins, Wee1, Myt1, and p21. These findings identify a novel role of DRG2 in G2/M progression. PMID:27669826

  17. A developmentally regulated translational control pathway establishes the meiotic chromosome segregation pattern

    PubMed Central

    Berchowitz, Luke E.; Gajadhar, Aaron S.; van Werven, Folkert J.; De Rosa, Alexandra A.; Samoylova, Mariya L.; Brar, Gloria A.; Xu, Yifeng; Xiao, Che; Futcher, Bruce; Weissman, Jonathan S.; White, Forest M.; Amon, Angelika

    2013-01-01

    Production of haploid gametes from diploid progenitor cells is mediated by a specialized cell division, meiosis, where two divisions, meiosis I and II, follow a single S phase. Errors in progression from meiosis I to meiosis II lead to aneuploid and polyploid gametes, but the regulatory mechanisms controlling this transition are poorly understood. Here, we demonstrate that the conserved kinase Ime2 regulates the timing and order of the meiotic divisions by controlling translation. Ime2 coordinates translational activation of a cluster of genes at the meiosis I–meiosis II transition, including the critical determinant of the meiotic chromosome segregation pattern CLB3. We further show that Ime2 mediates translational control through the meiosis-specific RNA-binding protein Rim4. Rim4 inhibits translation of CLB3 during meiosis I by interacting with the 5′ untranslated region (UTR) of CLB3. At the onset of meiosis II, Ime2 kinase activity rises and triggers a decrease in Rim4 protein levels, thereby alleviating translational repression. Our results elucidate a novel developmentally regulated translational control pathway that establishes the meiotic chromosome segregation pattern. PMID:24115771

  18. Driving Skills of Young Adults with Developmental Coordination Disorder: Regulating Speed and Coping with Distraction

    ERIC Educational Resources Information Center

    de Oliveira, Rita F.; Wann, John P.

    2011-01-01

    In two experiments, we used an automatic car simulator to examine the steering control, speed regulation and response to hazards of young adults with developmental coordination disorder (DCD) and limited driving experience. In Experiment 1 participants either used the accelerator pedal to regulate their speed, or used the brake pedal when they…

  19. (Regulation of teopene metabolism). Progress report. [Mentha piperita

    SciTech Connect

    Croteau, R.

    1985-01-01

    Progress in elucidating the biosynthesis of several monoterpenes in the peppermint is described. Tracer studies were performed to clarify metabolic pathways involved. Several growth regulators were screened for their influence on monoterpene composition and yield in peppermint and sage. (DT)

  20. Resilience as Regulation of Developmental and Family Processes

    PubMed Central

    MacPhee, David; Lunkenheimer, Erika; Riggs, Nathaniel

    2015-01-01

    Resilience can be defined as establishing equilibrium subsequent to disturbances to a system caused by significant adversity. When families experience adversity or transitions, multiple regulatory processes may be involved in establishing equilibrium, including adaptability, regulation of negative affect, and effective problem-solving skills. The authors’ resilience-as-regulation perspective integrates insights about the regulation of individual development with processes that regulate family systems. This middle-range theory of family resilience focuses on regulatory processes across levels that are involved in adaptation: whole-family systems such as routines and sense of coherence; coregulation of dyads involving emotion regulation, structuring, and reciprocal influences between social partners; and individual self-regulation. Insights about resilience-as-regulation are then applied to family-strengthening interventions that are designed to promote adaptation to adversity. Unresolved issues are discussed in relation to resilience-as-regulation in families, in particular how risk exposure is assessed, interrelations among family regulatory mechanisms, and how families scaffold the development of children’s resilience. PMID:26568647

  1. Gravid Spot Predicts Developmental Progress and Reproductive Output in a Livebearing Fish, Gambusia holbrooki

    PubMed Central

    Norazmi-Lokman, Nor Hakim; Purser, G. J.; Patil, Jawahar G.

    2016-01-01

    In most livebearing fish, the gravid spot is an excellent marker to identify brooding females, however its use to predict progress of embryonic development, brood size, timing of parturition and overall reproductive potential of populations remain unexplored. Therefore, to understand these relationships, this study quantified visual attributes (intensity and size) of the gravid spot in relation to key internal development in Gambusia holbrooki. Observations show that the colour of the gravid spot arises from progressive melanisation on the surface of the ovarian sac at its hind margin, rather than melanisation of the developing embryos or the skin of the brooding mother. More importantly, the gravid spot intensity and size were closely linked with both developmental stages and clutch size, suggesting their reliable use as external surrogates of key internal developmental in the species. Using predictive consistency of the gravid spot, we also determined the effect of rearing temperature (23°C and 25°C) on gestation period and parturition behaviour. The results show that gestation period was significantly reduced (F = 364.58; df = 1,48; P˃0.05) at 25°C. However there was no significant difference in average number of fry parturated in the two temperature groups (P<0.05), reaffirming that gravid spot intensity is a reliable predictor of reproductive output. The parturition in the species occurred predominantly in the morning and in contrast to earlier reports, tails of the fry emerged first with a few exceptions of head-first, twin and premature births. This study demonstrates utility of the gravid spot for downstream reproductive investigations in a live-bearing fish both in the field and laboratory. The reproducibility of the relationships (intensity with both developmental stage and clutch size), imply that they are also relevant to wild populations that experience varying temperature climes and stressors, significant deviations of which may serve as

  2. A developmentally regulated lectin in Bufo arenarum embryos.

    PubMed

    Elola, M T; Fink-de-Cabutti, N E; Herkovits, H

    1987-01-01

    We report the levels of an endogenous beta-galactoside lectin activity from Bufo arenarum whole embryos extracts and specific inhibition by saccharides at different developmental stages. Specific activity measured against trypsinized rabbit red blood cells showed relatively high and fluctuating levels during early stages (up to about 76 h post-fertilization) which fell to significantly lower and more constant values at late stages (77-264 h post-fertilization). Lactose is the most potent inhibitor of this lectin activity, and saccharides having alpha-galactoside configurations are weaker inhibitors. At the last embryonic stage, the agglutinating activity showed a different sugar specificity which suggests either the modification of the preexistent lectin or the synthesis of another type of lectin. The possible physiological roles of these lectins in the blockage of polyspermy or in embryonic cell-cell interactions are discussed.

  3. Mitochondria Are Linked to Calcium Stores in Striated Muscle by Developmentally Regulated Tethering Structures

    PubMed Central

    Boncompagni, Simona; Rossi, Ann E.; Micaroni, Massimo; Beznoussenko, Galina V.; Polishchuk, Roman S.; Dirksen, Robert T.

    2009-01-01

    Bi-directional calcium (Ca2+) signaling between mitochondria and intracellular stores (endoplasmic/sarcoplasmic reticulum) underlies important cellular functions, including oxidative ATP production. In striated muscle, this coupling is achieved by mitochondria being located adjacent to Ca2+ stores (sarcoplasmic reticulum [SR]) and in proximity of release sites (Ca2+ release units [CRUs]). However, limited information is available with regard to the mechanisms of mitochondrial-SR coupling. Using electron microscopy and electron tomography, we identified small bridges, or tethers, that link the outer mitochondrial membrane to the intracellular Ca2+ stores of muscle. This association is sufficiently strong that treatment with hypotonic solution results in stretching of the SR membrane in correspondence of tethers. We also show that the association of mitochondria to the SR is 1) developmentally regulated, 2) involves a progressive shift from a longitudinal clustering at birth to a specific CRU-coupled transversal orientation in adult, and 3) results in a change in the mitochondrial polarization state, as shown by confocal imaging after JC1 staining. Our results suggest that tethers 1) establish and maintain SR–mitochondrial association during postnatal maturation and in adult muscle and 2) likely provide a structural framework for bi-directional signaling between the two organelles in striated muscle. PMID:19037102

  4. SUMOylation-mediated regulation of cell cycle progression and cancer

    PubMed Central

    Eifler, Karolin; Vertegaal, Alfred C.O.

    2016-01-01

    SUMOylation plays critical roles during cell cycle progression. Many important cell cycle regulators, including many oncogenes and tumor suppressors, are functionally regulated via SUMOylation. The dynamic SUMOylation pattern observed throughout the cell cycle is ensured via distinct spatial and temporal regulation of the SUMO machinery. Additionally, SUMOylation cooperates with other post-translational modifications to mediate cell cycle progression. Deregulation of these SUMOylation and deSUMOylation enzymes causes severe defects in cell proliferation and genome stability. Different types of cancers were recently shown to be dependent on a functioning SUMOylation system, a finding that could potentially be exploited in anti-cancer therapies. PMID:26601932

  5. Absence of canonical active chromatin marks in developmentally regulated genes

    PubMed Central

    Ruiz-Romero, Marina; Corominas, Montserrat; Guigó, Roderic

    2015-01-01

    The interplay of active and repressive histone modifications is assumed to play a key role in the regulation of gene expression. In contrast to this generally accepted view, we show that transcription of genes temporally regulated during fly and worm development occurs in the absence of canonically active histone modifications. Conversely, strong chromatin marking is related to transcriptional and post-transcriptional stability, an association that we also observe in mammals. Our results support a model in which chromatin marking is associated to stable production of RNA, while unmarked chromatin would permit rapid gene activation and de-activation during development. In this case, regulation by transcription factors would play a comparatively more important regulatory role. PMID:26280901

  6. Microenvironmental regulation of tumor progression and metastasis

    PubMed Central

    Quail, DF; Joyce, JA

    2014-01-01

    Cancers develop in complex tissue environments, which they depend upon for sustained growth, invasion and metastasis. Unlike tumor cells, stromal cell types within the tumor microenvironment (TME) are genetically stable, and thus represent an attractive therapeutic target with reduced risk of resistance and tumor recurrence. However, specifically disrupting the pro-tumorigenic TME is a challenging undertaking, as the TME has diverse capacities to induce both beneficial and adverse consequences for tumorigenesis. Furthermore, many studies have shown that the microenvironment is capable of normalizing tumor cells, suggesting that reeducation of stromal cells, rather than targeted ablation per se, may be an effective strategy for treating cancer. Here, we will discuss the paradoxical roles of the TME during specific stages of cancer progression and metastasis, and recent therapeutic attempts to re-educate stromal cells within the TME to have anti-tumorigenic effects. PMID:24202395

  7. Macrophage/Epithelium Cross-Talk Regulates Cell Cycle Progression and Migration in Pancreatic Progenitors

    PubMed Central

    McLennan, Linsey; Gearhart, Addie; Jimenez-Caliani, Antonio J.; Cirulli, Vincenzo; Crisa, Laura

    2014-01-01

    Macrophages populate the mesenchymal compartment of all organs during embryogenesis and have been shown to support tissue organogenesis and regeneration by regulating remodeling of the extracellular microenvironment. Whether this mesenchymal component can also dictate select developmental decisions in epithelia is unknown. Here, using the embryonic pancreatic epithelium as model system, we show that macrophages drive the epithelium to execute two developmentally important choices, i.e. the exit from cell cycle and the acquisition of a migratory phenotype. We demonstrate that these developmental decisions are effectively imparted by macrophages activated toward an M2 fetal-like functional state, and involve modulation of the adhesion receptor NCAM and an uncommon “paired-less” isoform of the transcription factor PAX6 in the epithelium. Over-expression of this PAX6 variant in pancreatic epithelia controls both cell motility and cell cycle progression in a gene-dosage dependent fashion. Importantly, induction of these phenotypes in embryonic pancreatic transplants by M2 macrophages in vivo is associated with an increased frequency of endocrine-committed cells emerging from ductal progenitor pools. These results identify M2 macrophages as key effectors capable of coordinating epithelial cell cycle withdrawal and cell migration, two events critical to pancreatic progenitors' delamination and progression toward their differentiated fates. PMID:24586821

  8. Developmental regulation of. beta. -conglycinin in soybean axes and cotyledons

    SciTech Connect

    Ladin, B.F.; Tierney, M.L.; Meinke, D.W.; Hosangadi, P.; Veith, M.; Beachy, R.N.

    1987-05-01

    Analysis of the expression of genes encoding the ..beta..-conglycinin seed storage proteins in soybean has been used to extend the authors understanding of developmental gene expression in plants. The ..cap alpha..,..cap alpha..', and ..beta.. subunits of ..beta..-conglycinin are encoded by a multigene family which is organ-specific in its expression. In this study the authors report the differentially programmed accumulation of the ..cap alpha..,..cap alpha..', and ..beta.. subunits of ..beta..-conglycinin. Multiple isomeric forms of each subunit are present in the dry seed, but the timing of their accumulation is unique for each subunit. The previously reported variation in amount of ..cap alpha..' and ..cap alpha.. subunits in axis and cotyledons is also reflected in the amount of subunit specific mRNA which is present in each tissue. The ..beta.. subunit, previously undetected in soybean axes, is found to be synthesized but rapidly degraded. These differences in ..beta..-conglycinin protein accumulation may be reflected by the morphological differences observed in protein bodies between these two tissues.

  9. Hemodynamic forces regulate developmental patterning of atrial conduction.

    PubMed

    Bressan, Michael C; Louie, Jonathan D; Mikawa, Takashi

    2014-01-01

    Anomalous action potential conduction through the atrial chambers of the heart can lead to severe cardiac arrhythmia. To date, however, little is known regarding the mechanisms that pattern proper atrial conduction during development. Here we demonstrate that atrial muscle functionally diversifies into at least two heterogeneous subtypes, thin-walled myocardium and rapidly conducting muscle bundles, during a developmental window just following cardiac looping. During this process, atrial muscle bundles become enriched for the fast conduction markers Cx40 and Nav1.5, similar to the precursors of the fast conduction Purkinje fiber network located within the trabeculae of the ventricles. In contrast to the ventricular trabeculae, however, atrial muscle bundles display an increased proliferation rate when compared to the surrounding myocardium. Interestingly, mechanical loading of the embryonic atrial muscle resulted in an induction of Cx40, Nav1.5 and the cell cycle marker Cyclin D1, while decreasing atrial pressure via in vivo ligation of the vitelline blood vessels results in decreased atrial conduction velocity. Taken together, these data establish a novel model for atrial conduction patterning, whereby hemodynamic stretch coordinately induces proliferation and fast conduction marker expression, which in turn promotes the formation of large diameter muscle bundles to serve as preferential routes of conduction.

  10. Developmental regulation of aromatase activity in the rat hypothalamus

    SciTech Connect

    Lephart, E.D.

    1989-01-01

    The brain of all mammalian species studied thus far contain an enzymatic activity (aromatase) that catalyzes the conversion of androgens to estrogens. The activity is highest during prenatal development and contributes to the establishment of sex differences which determine adult gonadotropin secretion patterns and reproductive behavior. The studies presented in this dissertation represent a systematic effort to elucidate the mechanism(s) that control the initiation of and contribute to maintaining rat hypothalamic aromatase activity during pre- and postnatal development. Aromatase enzyme activity was measured by the {sup 3}H{sub 2}O release assay or by traditional estrogen product isolation. Brain aromatase mRNA was detected by hybridization to a cDNA encoding rat aromatase cytochrome P-450. In both males and females the time of puberty was associated with a decline in hypothalamic aromatase activity. This decline may represent a factor underlying the peri-pubertal decrease in the sensitivity to gonadal steroid feedback that accompanies completion of puberty. The results also indicate that androgens regulate brain aromatase levels during both the prepubertal and peri-pubertal stages of sexual development and that this regulation is transiently lost in young adults. Utilizing a hypothalamic organotypic culture system, aromatase activity in vitro was maintained for as long as two days. The results of studies of a variety of hormonal and metabolic regulators suggest that prenatal aromatase activity is regulated by factor(s) that function independently from the classical cyclic AMP and protein kinase C trans-membrane signaling pathways.

  11. A Developmental Psychopathology Perspective on ADHD and Comorbid Conditions: The Role of Emotion Regulation.

    PubMed

    Steinberg, Elizabeth A; Drabick, Deborah A G

    2015-12-01

    Research investigating attention-deficit/hyperactivity disorder (ADHD) and co-occurring disorders such as oppositional defiant disorder, conduct disorder, anxiety, and depression has surged in popularity; however, the developmental relations between ADHD and these comorbid conditions remain poorly understood. The current paper uses a developmental psychopathology perspective to examine conditions commonly comorbid with ADHD during late childhood through adolescence. First, we present evidence for ADHD and comorbid disorders. Next, we discuss emotion regulation and its associations with ADHD. The role of parenting behaviors in the development and maintenance of emotion regulation difficulties and comorbid disorders among children with ADHD is explored. An illustrative example of emotion regulation and parenting over the course of development is provided to demonstrate bidirectional relations among these constructs. We then present an integrated conceptual model of emotion regulation as a shared risk process that may lead to different comorbid conditions among children with ADHD. Implications and directions for future research are presented.

  12. The Developmental Regulator SEEDSTICK Controls Structural and Mechanical Properties of the Arabidopsis Seed Coat.

    PubMed

    Ezquer, Ignacio; Mizzotti, Chiara; Nguema-Ona, Eric; Gotté, Maxime; Beauzamy, Léna; Viana, Vivian Ebeling; Dubrulle, Nelly; Costa de Oliveira, Antonio; Caporali, Elisabetta; Koroney, Abdoul-Salam; Boudaoud, Arezki; Driouich, Azeddine; Colombo, Lucia

    2016-10-01

    Although many transcription factors involved in cell wall morphogenesis have been identified and studied, it is still unknown how genetic and molecular regulation of cell wall biosynthesis is integrated into developmental programs. We demonstrate by molecular genetic studies that SEEDSTICK (STK), a transcription factor controlling ovule and seed integument identity, directly regulates PMEI6 and other genes involved in the biogenesis of the cellulose-pectin matrix of the cell wall. Based on atomic force microscopy, immunocytochemistry, and chemical analyses, we propose that structural modifications of the cell wall matrix in the stk mutant contribute to defects in mucilage release and seed germination under water-stress conditions. Our studies reveal a molecular network controlled by STK that regulates cell wall properties of the seed coat, demonstrating that developmental regulators controlling organ identity also coordinate specific aspects of cell wall characteristics.

  13. New Directions in Developmental Emotion Regulation Research across the Life Span: Introduction to the Special Section

    ERIC Educational Resources Information Center

    Zimmermann, Peter; Thompson, Ross A.

    2014-01-01

    Research on the development of emotion regulation has become a prominent topic in developmental science covering a broad age range from infancy to old age because of its theoretical importance and practical implications. This introductory essay of this special section includes reflections on some of the conceptual themes of this research field and…

  14. Molecular Analysis of the Developmental and Hormonal Systems Regulating Fruit Ripening

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The ripening and development of fleshy fruits is regulated by environmental, hormonal and developmental cues. Ethylene is the key ripening hormone of climacteric fruits and can influence ripening in many non-climacteric fruits. Our laboratory uses tomato as a model system to understand ripening re...

  15. GLUCOCORTICOID RECEPTOR REGULATION IN THE RAT EMBRYO: A POTENTIAL SITE FOR DEVELOPMENTAL TOXICITY?

    EPA Science Inventory

    Glucocorticoid receptor regulation in the rat embryo: a potential site for developmental toxicity?

    Ghosh B, Wood CR, Held GA, Abbott BD, Lau C.

    National Research Council, U.S. Environmental Protection Agency, Research Triangle Park, North Carolina 27711, USA.

  16. SNAT2 and LAT1 transporter abundance is developmentally regulated in skeletal muscle of neonatal pigs

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Previously, we demonstrated that the insulin and amino acid–induced activation of the mammalian target of rapamycin complex 1 (mTORC1), is developmentally regulated in neonatal pigs. Recent studies have indicated an important role of the System A transporters (SNAT2 and SLC1A5) and the L transporter...

  17. Enhancer-core-promoter specificity separates developmental and housekeeping gene regulation.

    PubMed

    Zabidi, Muhammad A; Arnold, Cosmas D; Schernhuber, Katharina; Pagani, Michaela; Rath, Martina; Frank, Olga; Stark, Alexander

    2015-02-26

    Gene transcription in animals involves the assembly of RNA polymerase II at core promoters and its cell-type-specific activation by enhancers that can be located more distally. However, how ubiquitous expression of housekeeping genes is achieved has been less clear. In particular, it is unknown whether ubiquitously active enhancers exist and how developmental and housekeeping gene regulation is separated. An attractive hypothesis is that different core promoters might exhibit an intrinsic specificity to certain enhancers. This is conceivable, as various core promoter sequence elements are differentially distributed between genes of different functions, including elements that are predominantly found at either developmentally regulated or at housekeeping genes. Here we show that thousands of enhancers in Drosophila melanogaster S2 and ovarian somatic cells (OSCs) exhibit a marked specificity to one of two core promoters--one derived from a ubiquitously expressed ribosomal protein gene and another from a developmentally regulated transcription factor--and confirm the existence of these two classes for five additional core promoters from genes with diverse functions. Housekeeping enhancers are active across the two cell types, while developmental enhancers exhibit strong cell-type specificity. Both enhancer classes differ in their genomic distribution, the functions of neighbouring genes, and the core promoter elements of these neighbouring genes. In addition, we identify two transcription factors--Dref and Trl--that bind and activate housekeeping versus developmental enhancers, respectively. Our results provide evidence for a sequence-encoded enhancer-core-promoter specificity that separates developmental and housekeeping gene regulatory programs for thousands of enhancers and their target genes across the entire genome.

  18. Developmental regulation of cation pumps in skeletal and cardiac muscle.

    PubMed

    Dauncey, M J; Harrison, A P

    1996-03-01

    The prenatal and early postnatal periods are critical stages during which long-term development can be affected. For example, retardation of growth during these periods is closely linked to the occurrence of adult degenerative diseases. Appropriate development of muscle is essential for numerous functions, including movement, posture, thermogenesis, breathing and maintenance of the circulation. Defects in normal muscle development could thus impair any of these functions in the neonate and may also have long-term consequences for the health of the individual. Central to normal muscle structure and function is the appropriate development not only of the sarcomeric proteins but also of the sarcolemma, transverse-tubules, sarcoplasmic reticulum and associated membrane-bound ATPases. Long-term regulation of these ATPases is by changes in their concentration, whereas short-term regulation is mediated by alterations in enzyme activity. This review focuses on changes in total concentrations of Na+, K+, and Ca(2+)-ATPases during prenatal and postnatal life, in functionally diverse muscles of mammalian species born at different stages of maturity. Both these cation pumps belong to multigene families and changes in relative abundance of their specific isoforms are also considered because they may have important consequences for contractile performance during distinct stages of development. Finally, potential regulatory mechanisms which alter markedly during normal ontogeny are discussed. These include intrinsic factors such as hormones and contractile activity, extrinsic factors such as nutrition and environmental temperature, and interactions between these variables which are known to be especially important during postnatal development.

  19. Early development of Moniliophthora perniciosa basidiomata and developmentally regulated genes

    PubMed Central

    2009-01-01

    Background The hemibiotrophic fungus Moniliophthora perniciosa is the causal agent of Witches' broom, a disease of Theobroma cacao. The pathogen life cycle ends with the production of basidiocarps in dead tissues of the infected host. This structure generates millions of basidiospores that reinfect young tissues of the same or other plants. A deeper understanding of the mechanisms underlying the sexual phase of this fungus may help develop chemical, biological or genetic strategies to control the disease. Results Mycelium was morphologically analyzed prior to emergence of basidiomata by stereomicroscopy, light microscopy and scanning electron microscopy. The morphological changes in the mycelium before fructification show a pattern similar to other members of the order Agaricales. Changes and appearance of hyphae forming a surface layer by fusion were correlated with primordia emergence. The stages of hyphal nodules, aggregation, initial primordium and differentiated primordium were detected. The morphological analysis also allowed conclusions on morphogenetic aspects. To analyze the genes involved in basidiomata development, the expression of some selected EST genes from a non-normalized cDNA library, representative of the fruiting stage of M. perniciosa, was evaluated. A macroarray analysis was performed with 192 selected clones and hybridized with two distinct RNA pools extracted from mycelium in different phases of basidiomata formation. This analysis showed two groups of up and down-regulated genes in primordial phases of mycelia. Hydrophobin coding, glucose transporter, Rho-GEF, Rheb, extensin precursor and cytochrome p450 monooxygenase genes were grouped among the up-regulated. In the down-regulated group relevant genes clustered coding calmodulin, lanosterol 14 alpha demethylase and PIM1. In addition, 12 genes with more detailed expression profiles were analyzed by RT-qPCR. One aegerolysin gene had a peak of expression in mycelium with primordia and a

  20. The PIKE homolog Centaurin gamma regulates developmental timing in Drosophila.

    PubMed

    Gündner, Anna Lisa; Hahn, Ines; Sendscheid, Oliver; Aberle, Hermann; Hoch, Michael

    2014-01-01

    Phosphoinositide-3-kinase enhancer (PIKE) proteins encoded by the PIKE/CENTG1 gene are members of the gamma subgroup of the Centaurin superfamily of small GTPases. They are characterized by their chimeric protein domain architecture consisting of a pleckstrin homology (PH) domain, a GTPase-activating (GAP) domain, Ankyrin repeats as well as an intrinsic GTPase domain. In mammals, three PIKE isoforms with variations in protein structure and subcellular localization are encoded by the PIKE locus. PIKE inactivation in mice results in a broad range of defects, including neuronal cell death during brain development and misregulation of mammary gland development. PIKE -/- mutant mice are smaller, contain less white adipose tissue, and show insulin resistance due to misregulation of AMP-activated protein kinase (AMPK) and insulin receptor/Akt signaling. here, we have studied the role of PIKE proteins in metabolic regulation in the fly. We show that the Drosophila PIKE homolog, ceng1A, encodes functional GTPases whose internal GAP domains catalyze their GTPase activity. To elucidate the biological function of ceng1A in flies, we introduced a deletion in the ceng1A gene by homologous recombination that removes all predicted functional PIKE domains. We found that homozygous ceng1A mutant animals survive to adulthood. In contrast to PIKE -/- mouse mutants, genetic ablation of Drosophila ceng1A does not result in growth defects or weight reduction. Although metabolic pathways such as insulin signaling, sensitivity towards starvation and mobilization of lipids under high fed conditions are not perturbed in ceng1A mutants, homozygous ceng1A mutants show a prolonged development in second instar larval stage, leading to a late onset of pupariation. In line with these results we found that expression of ecdysone inducible genes is reduced in ceng1A mutants. Together, we propose a novel role for Drosophila Ceng1A in regulating ecdysone signaling-dependent second to third instar

  1. Transcription factor Wilms’ tumor 1 regulates developmental RNAs through 3′ UTR interaction

    PubMed Central

    Bharathavikru, Ruthrothaselvi; Dudnakova, Tatiana; Aitken, Stuart; Slight, Joan; Artibani, Mara; Hohenstein, Peter; Tollervey, David; Hastie, Nick

    2017-01-01

    Wilms’ tumor 1 (WT1) is essential for the development and homeostasis of multiple mesodermal tissues. Despite evidence for post-transcriptional roles, no endogenous WT1 target RNAs exist. Using RNA immunoprecipitation and UV cross-linking, we show that WT1 binds preferentially to 3′ untranslated regions (UTRs) of developmental targets. These target mRNAs are down-regulated upon WT1 depletion in cell culture and developing kidney mesenchyme. Wt1 deletion leads to rapid turnover of specific mRNAs. WT1 regulates reporter gene expression through interaction with 3′ UTR-binding sites. Combining experimental and computational analyses, we propose that WT1 influences key developmental and disease processes in part through regulating mRNA turnover. PMID:28289143

  2. Alcohol induced epigenetic alterations to developmentally crucial genes regulating neural stemness and differentiation

    PubMed Central

    Veazey, Kylee J.; Carnahan, Mindy N.; Muller, Daria; Miranda, Rajesh C.; Golding, Michael C.

    2013-01-01

    histone code and errors in the epigenetic program. These observations indicate that alterations to chromatin structure may represent a crucial component of alcohol teratogenesis and progress towards a better understanding of the developmental origins of FASDs. PMID:23488822

  3. Assessing the Phonological Skills of Bilingual Children from Preschool through Kindergarten: Developmental Progression and Cross-Language Transfer

    ERIC Educational Resources Information Center

    Lopez, Lisa M.

    2012-01-01

    The developmental progression hypothesis for phonological awareness states that children perform better on lower level tasks and has been addressed mainly in the literature with children beginning at age 5. In addition, there has been a limited amount of research done regarding the performance of dual-language learners younger than age 5 on…

  4. Developmental regulation of transcription initiation: more than just changing the actors.

    PubMed

    Müller, Ferenc; Zaucker, Andreas; Tora, Làszlò

    2010-10-01

    The traditional model of transcription initiation nucleated by the TFIID complex has suffered significant erosion in the last decade. The discovery of cell-specific paralogs of TFIID subunits and a variety of complexes that replace TFIID in transcription initiation of protein coding genes have been paralleled by the description of diverse core promoter sequences. These observations suggest an additional level of regulation of developmental and tissue-specific gene expression at the core promoter level. Recent work suggests that this regulation may function through specific roles of distinct TBP-type factors and TBP-associated factors (TAFs), however the picture emerging is still far from complete. Here we summarize the proposed models of transcription initiation by alternative initiation complexes in distinct stages of developmental specialization during vertebrate ontogeny.

  5. Cyclic AMP stabilizes a class of developmentally regulated Dictyostelium discoideum mRNAs.

    PubMed

    Mangiarotti, G; Ceccarelli, A; Lodish, H F

    The stability of mRNA is an important facet of the regulation of protein synthesis. In mammalian cells most mRNAs have long half-lives (5-15 hours) but a substantial fraction are much less stable. There are few examples where the stability of a particular mRNA or class of mRNAs is specifically affected by environmental or developmental stimuli. Certain hormones cause specific stabilization of mRNAs species and preferential mRNA stability is important in the accumulation of globin and myosin mRNAs during the terminal stages of erythropoesis or myogenesis, respectively. Disaggregation of Dictyostelium discoideum aggregates induces the specific destabilization of a large class of developmentally regulated mRNAs; thus, this system is an excellent one in which to determine how such controls are effected. Here we show that addition of cyclic AMP to disaggregated cells specifically prevents the destabilization of these mRNAs.

  6. Light-independent developmental regulation of cab gene expression in Arabidopsis thaliana seedlings.

    PubMed Central

    Brusslan, J A; Tobin, E M

    1992-01-01

    We found a transient increase in the amount of mRNA for four nuclear genes encoding chloroplast proteins during early development of Arabidopsis thaliana. This increase began soon after germination as cotyledons emerged from the seed coat; it occurred in total darkness and was not affected by external factors, such as gibberellins or light treatments used to stimulate germination. Three members of the cab gene family and the rbcS-1A gene exhibited this expression pattern. Because timing of the increase coincided with cotyledon emergence and because it occurred independently of external stimuli, we suggest that this increase represents developmental regulation of these genes. Further, 1.34 kilobases of the cab1 promoter was sufficient to confer this expression pattern on a reporter gene in transgenic Arabidopsis seedlings. The ability of the cab genes to respond to phytochrome preceded this developmental increase, showing that these two types of regulation are independent. Images PMID:1380166

  7. Descriptive analysis of the developmental progression of grip position for pencil and crayon control in nondysfunctional children.

    PubMed

    Schneck, C M; Henderson, A

    1990-10-01

    This study was designed to investigate the developmental progression in pencil and crayon grip. The subjects were 320 nondysfunctional children aged 3.0 to 6.11 years, with 20 boys and 20 girls at each 6-month age interval. On the basis of a review of the literature, developmental pencil and crayon grips were defined for the study, and the type of grips each child used to perform a drawing task and a coloring task were recorded. Many children at each age level used mature pencil grips. A developmental progression, however, was shown by the percentage change of children at each age level who used mature grips. Forty-eight percent of the youngest group used mature grips, compared with 90% of the oldest children. Two pencil grips-dynamic and lateral tripod-appear to be common in older children. Differences in the developmental progression of pencil grip were noted between boys and girls and between a drawing task and a coloring task.

  8. INO80-dependent regression of ecdysone-induced transcriptional responses regulates developmental timing in Drosophila.

    PubMed

    Neuman, Sarah D; Ihry, Robert J; Gruetzmacher, Kelly M; Bashirullah, Arash

    2014-03-15

    Sequential pulses of the steroid hormone ecdysone regulate the major developmental transitions in Drosophila, and the duration of each developmental stage is determined by the length of time between ecdysone pulses. Ecdysone regulates biological responses by directly initiating target gene transcription. In turn, these transcriptional responses are known to be self-limiting, with mechanisms in place to ensure regression of hormone-dependent transcription. However, the biological significance of these transcriptional repression mechanisms remains unclear. Here we show that the chromatin remodeling protein INO80 facilitates transcriptional repression of ecdysone-regulated genes during prepupal development. In ino80 mutant animals, inefficient repression of transcriptional responses to the late larval ecdysone pulse delays the onset of the subsequent prepupal ecdysone pulse, resulting in a significantly longer prepupal stage. Conversely, increased expression of ino80 is sufficient to shorten the prepupal stage by increasing the rate of transcriptional repression. Furthermore, we demonstrate that enhancing the rate of regression of the mid-prepupal competence factor βFTZ-F1 is sufficient to determine the timing of head eversion and thus the duration of prepupal development. Although ino80 is conserved from yeast to humans, this study represents the first characterization of a bona fide ino80 mutation in any metazoan, raising the possibility that the functions of ino80 in transcriptional repression and developmental timing are evolutionarily conserved.

  9. Feeding state-dependent regulation of developmental plasticity via CaMKI and neuroendocrine signaling

    PubMed Central

    Neal, Scott J; Takeishi, Asuka; O'Donnell, Michael P; Park, JiSoo; Hong, Myeongjin; Butcher, Rebecca A; Kim, Kyuhyung; Sengupta, Piali

    2015-01-01

    Information about nutrient availability is assessed via largely unknown mechanisms to drive developmental decisions, including the choice of Caenorhabditis elegans larvae to enter into the reproductive cycle or the dauer stage. In this study, we show that CMK-1 CaMKI regulates the dauer decision as a function of feeding state. CMK-1 acts cell-autonomously in the ASI, and non cell-autonomously in the AWC, sensory neurons to regulate expression of the growth promoting daf-7 TGF-β and daf-28 insulin-like peptide (ILP) genes, respectively. Feeding state regulates dynamic subcellular localization of CMK-1, and CMK-1-dependent expression of anti-dauer ILP genes, in AWC. A food-regulated balance between anti-dauer ILP signals from AWC and pro-dauer signals regulates neuroendocrine signaling and dauer entry; disruption of this balance in cmk-1 mutants drives inappropriate dauer formation under well-fed conditions. These results identify mechanisms by which nutrient information is integrated in a small neuronal network to modulate neuroendocrine signaling and developmental plasticity. DOI: http://dx.doi.org/10.7554/eLife.10110.001 PMID:26335407

  10. Synchronization of Developmental Processes and Defense Signaling by Growth Regulating Transcription Factors

    PubMed Central

    Liu, Jinyi; Rice, J. Hollis; Chen, Nana; Baum, Thomas J.; Hewezi, Tarek

    2014-01-01

    Growth regulating factors (GRFs) are a conserved class of transcription factor in seed plants. GRFs are involved in various aspects of tissue differentiation and organ development. The implication of GRFs in biotic stress response has also been recently reported, suggesting a role of these transcription factors in coordinating the interaction between developmental processes and defense dynamics. However, the molecular mechanisms by which GRFs mediate the overlaps between defense signaling and developmental pathways are elusive. Here, we report large scale identification of putative target candidates of Arabidopsis GRF1 and GRF3 by comparing mRNA profiles of the grf1/grf2/grf3 triple mutant and those of the transgenic plants overexpressing miR396-resistant version of GRF1 or GRF3. We identified 1,098 and 600 genes as putative targets of GRF1 and GRF3, respectively. Functional classification of the potential target candidates revealed that GRF1 and GRF3 contribute to the regulation of various biological processes associated with defense response and disease resistance. GRF1 and GRF3 participate specifically in the regulation of defense-related transcription factors, cell-wall modifications, cytokinin biosynthesis and signaling, and secondary metabolites accumulation. GRF1 and GRF3 seem to fine-tune the crosstalk between miRNA signaling networks by regulating the expression of several miRNA target genes. In addition, our data suggest that GRF1 and GRF3 may function as negative regulators of gene expression through their association with other transcription factors. Collectively, our data provide new insights into how GRF1 and GRF3 might coordinate the interactions between defense signaling and plant growth and developmental pathways. PMID:24875638

  11. Developmental regulation of a proinsulin messenger RNA generated by intron retention

    PubMed Central

    Mansilla, Alicia; López-Sánchez, Carmen; de la Rosa, Enrique J; García-Martínez, Virginio; Martínez-Salas, Encarna; de Pablo, Flora; Hernández-Sánchez, Catalina

    2005-01-01

    Proinsulin gene expression regulation and function during early embryonic development differ remarkably from those found in postnatal organisms. The embryonic proinsulin protein content decreased from gastrulation to neurulation in contrast with the overall proinsulin messenger RNA increase. This is due to increasing levels of a proinsulin mRNA variant generated by intron 1 retention in the 5′ untranslated region. Inclusion of intron 1 inhibited proinsulin translation almost completely without affecting nuclear export or cytoplasmic decay. The novel proinsulin mRNA isoform expression was developmentally regulated and tissue specific. The proportion of intron retention increased from gastrulation to organogenesis, was highest in the heart tube and presomitic region, and could not be detected in the pancreas. Notably, proinsulin addition induced cardiac marker gene expression in the early embryonic stages when the translationally active transcript was expressed. We propose that regulated unproductive splicing and translation is a mechanism that regulates proinsulin expression in accordance with specific requirements in developing vertebrates. PMID:16179943

  12. GABAergic synaptic plasticity during a developmentally regulated sleep-like state in C. elegans.

    PubMed

    Dabbish, Nooreen S; Raizen, David M

    2011-11-02

    Approximately one-fourth of the neurons in Caenorhabditis elegans adults are born during larval development, indicating tremendous plasticity in larval nervous system structure. Larval development shows cyclical expression of sleep-like quiescent behavior during lethargus periods, which occur at larval stage transitions. We studied plasticity at the neuromuscular junction during lethargus using the acetylcholinesterase inhibitor aldicarb. The rate of animal contraction when exposed to aldicarb is controlled by the balance between excitatory cholinergic and inhibitory GABAergic input on the muscle. During lethargus, there is an accelerated rate of contraction on aldicarb. Mutant analysis and optogenetic studies reveal that GABAergic synaptic transmission is reduced during lethargus. Worms in lethargus show partial resistance to GABA(A) receptor agonists, indicating that postsynaptic mechanisms contribute to lethargus-dependent plasticity. Using genetic manipulations that separate the quiescent state from the developmental stage, we show that the synaptic plasticity is dependent on developmental time and not on the behavioral state of the animal. We propose that the synaptic plasticity regulated by a developmental clock in C. elegans is analogous to synaptic plasticity regulated by the circadian clock in other species.

  13. The systemin precursor gene regulates both defensive and developmental genes in Solanum tuberosum.

    PubMed

    Narváez-Vasquez, Javier; Ryan, Clarence A

    2002-11-26

    Transformation of Solanum tuberosum, cv. Desiree, with the tomato prosystemin gene, regulated by the 35S cauliflower mosaic virus promoter, resulted in constitutive increase in defensive proteins in potato leaves, similar to its effects in tomato plants, but also resulted in a dramatic increase in storage protein levels in potato tubers. Tubers from selected transformed lines contained 4- to 5-fold increases in proteinase inhibitor I and II proteins, >50% more soluble and dry weight protein, and >50% more total nitrogen and total free amino acids than found in wild-type tubers. These results suggest that the prosystemin gene plays a dual role in potato plants in regulating proteinase inhibitor synthesis in leaves in response to wounding and in regulating storage protein synthesis in potato tubers in response to developmental cues. The results indicated that components of the systemin signaling pathway normally found in leaves have been recruited by potato plants to be developmentally regulated to synthesize and accumulate large quantities of storage proteins in tubers.

  14. Regulation of cell division in higher plants. Progress report

    SciTech Connect

    Jacobs, T.W.

    1992-07-01

    Cell division is arguably the most fundamental of all developmental processes. In higher plants, mitotic activity is largely confined to foci of patterned cell divisions called meristems. From these perpetually embryonic tissues arise the plant`s essential organs of light capture, support, protection and reproduction. Once an adequate understanding of plant cell mitotic regulation is attained, unprecedented opportunities will ensue for analyzing and genetically controlling diverse aspects of development, including plant architecture, leaf shape, plant height, and root depth. The mitotic cycle in a variety of model eukaryotic systems in under the control of a regulatory network of striking evolutionary conservation. Homologues of the yeast cdc2 gene, its catalytic product, p34, and the cyclin regulatory subunits of the MPF complex have emerged as ubiquitous mitotic regulators. We have cloned cdc2-like and cyclin genes from pea. As in other eukaryotic model systems, p34 of Pisum sativum is a subunit of a high molecular weight complex which binds the fission yeast p13 protein and displays histone H1 kinase activity in vitro. Our primary objective in this study is to gain baseline information about the regulation of this higher plant cell division control complex in non-dividing, differentiated cells as well as in synchronous and asynchronous mitotic cells. We are investigating cdc2 and cyclin expression at the levels of protein abundance, protein phosphorylation and quaternary associations.

  15. Enhancer of zeste acts as a major developmental regulator of Ciona intestinalis embryogenesis.

    PubMed

    Le Goff, Emilie; Martinand-Mari, Camille; Martin, Marianne; Feuillard, Jérôme; Boublik, Yvan; Godefroy, Nelly; Mangeat, Paul; Baghdiguian, Stephen; Cavalli, Giacomo

    2015-08-14

    The paradigm of developmental regulation by Polycomb group (PcG) proteins posits that they maintain silencing outside the spatial expression domains of their target genes, particularly of Hox genes, starting from mid embryogenesis. The Enhancer of zeste [E(z)] PcG protein is the catalytic subunit of the PRC2 complex, which silences its targets via deposition of the H3K27me3 mark. Here, we studied the ascidian Ciona intestinalis counterpart of E(z). Ci-E(z) is detected by immunohistochemistry as soon as the 2- and 4-cell stages as a cytoplasmic form and becomes exclusively nuclear thereafter, whereas the H3K27me3 mark is detected starting from the gastrula stage and later. Morpholino invalidation of Ci-E(z) leads to the total disappearance of both Ci-E(z) protein and its H3K27me3 mark. Ci-E(z) morphants display a severe phenotype. Strikingly, the earliest defects occur at the 4-cell stage with the dysregulation of cell positioning and mitotic impairment. At later stages, Ci-E(z)-deficient embryos are affected by terminal differentiation defects of neural, epidermal and muscle tissues, by the failure to form a notochord and by the absence of caudal nerve. These major phenotypic defects are specifically rescued by injection of a morpholino-resistant Ci-E(z) mRNA, which restores expression of Ci-E(z) protein and re-deposition of the H3K27me3 mark. As observed by qPCR analyses, Ci-E(z) invalidation leads to the early derepression of tissue-specific developmental genes, whereas late-acting developmental genes are generally down-regulated. Altogether, our results suggest that Ci-E(z) plays a major role during embryonic development in Ciona intestinalis by silencing early-acting developmental genes in a Hox-independent manner.

  16. FSH Regulates mRNA Translation in Mouse Oocytes and Promotes Developmental Competence.

    PubMed

    Franciosi, Federica; Manandhar, Shila; Conti, Marco

    2016-02-01

    A major challenge in assisted reproductive technology is to develop conditions for in vitro oocyte maturation yielding high-quality eggs. Efforts are underway to assess whether known hormonal and local factors play a role in oocyte developmental competence and to identify the molecular mechanism involved. Here we have tested the hypothesis that FSH improves oocyte developmental competence by regulating the translational program in the oocyte. Accumulation of oocyte proteins (targeting protein for the Xenopus kinesin xklp2 and IL-7) associated with improved oocyte quality is increased when cumulus-oocyte complexes are incubated with FSH. This increase is due to enhanced translation of the corresponding mRNAs, as indicated by microinjection of constructs in which the 3' untranslated region of the Tpx2 or Il7 transcripts is fused to the luciferase reporter. A transient activation of the phosphatidyl-inositol 3-phosphate/AKT cascade in the oocyte preceded the increase in translation. When the epidermal growth factor (EGF) receptor is down-regulated in follicular cells, the FSH-induced rate of maternal mRNA translation and AKT activation were lost, demonstrating that the effects of FSH are indirect and require EGF receptor signaling in the somatic compartment. Using Pten(fl/fl):Zp3cre oocytes in which the AKT is constitutively activated, translation of reporters was increased and was no longer sensitive to FSH stimulation. More importantly, the oocytes lacking the phosphate and tensin homolog gene showed increased developmental competence, even when cultured in the absence of FSH or growth factors. Thus, we demonstrate that FSH intersects with the follicular EGF network to activate the phosphatidyl-inositol 3-phosphate/AKT cascade in the oocyte to control translation and developmental competence. These findings provide a molecular rationale for the use of FSH to improve egg quality.

  17. An Examination of the Impact of Accelerating Community College Students' Progression through Developmental Education

    ERIC Educational Resources Information Center

    Hodara, Michelle; Jaggars, Shanna Smith

    2014-01-01

    In an effort to improve developmental education students' outcomes, community colleges have been experimenting with acceleration strategies. Models of acceleration allow students to complete their developmental requirements in a shorter amount of time. However, there has been limited empirical research on the effects of accelerating students'…

  18. Tumor suppressor Lzap regulates cell cycle progression, doming and zebrafish epiboly

    PubMed Central

    Liu, Dan; Wang, Wen-Der; Melville, David B.; Cha, Yong I.; Yin, Zhirong; Issaeva, Natalia; Knapik, Ela W.; Yarbrough, Wendell G.

    2012-01-01

    Initial stages of embryonic development rely on rapid, synchronized cell divisions of the fertilized egg followed by a set of morphogenetic movements collectively called epiboly and gastrulation. Lzap is a putative tumor suppressor whose expression is lost in 30% of head and neck squamous cell carcinomas. Lzap activities include regulation of cell cycle progression and response to therapeutic agents. Here we explore developmental roles of the lzap gene during zebrafish morphogenesis. Lzap is highly conserved among vertebrates and is maternally deposited. Expression is initially ubiquitous during gastrulation, and later becomes more prominent in the pharyngeal arches, digestive tract and brain. Antisense morpholino-mediated depletion of Lzap resulted in delayed cell divisions and apoptosis during blastomere formation, resulting in fewer, larger cells. Cell cycle analysis suggested that Lzap loss in early embryonic cells resulted in a G2/M arrest. Furthermore, the Lzap-deficient embryos failed to initiate epiboly – the earliest morphogenetic movement in animal development – which has been shown to be dependent on cell adhesion and migration of epithelial sheets. Our results strongly implicate Lzap in regulation of cell cycle progression, adhesion and migratory activity of epithelial cell sheets during early development. These functions provide further insight into Lzap activity that may contribute not only to development, but also to tumor formation. PMID:21523853

  19. CDK8-Cyclin C Mediates Nutritional Regulation of Developmental Transitions through the Ecdysone Receptor in Drosophila

    PubMed Central

    Xie, Xiao-Jun; Hsu, Fu-Ning; Gao, Xinsheng; Xu, Wu; Ni, Jian-Quan; Xing, Yue; Huang, Liying; Hsiao, Hao-Ching; Zheng, Haiyan; Wang, Chenguang; Zheng, Yani; Xiaoli, Alus M.; Yang, Fajun; Bondos, Sarah E.; Ji, Jun-Yuan

    2015-01-01

    The steroid hormone ecdysone and its receptor (EcR) play critical roles in orchestrating developmental transitions in arthropods. However, the mechanism by which EcR integrates nutritional and developmental cues to correctly activate transcription remains poorly understood. Here, we show that EcR-dependent transcription, and thus, developmental timing in Drosophila, is regulated by CDK8 and its regulatory partner Cyclin C (CycC), and the level of CDK8 is affected by nutrient availability. We observed that cdk8 and cycC mutants resemble EcR mutants and EcR-target genes are systematically down-regulated in both mutants. Indeed, the ability of the EcR-Ultraspiracle (USP) heterodimer to bind to polytene chromosomes and the promoters of EcR target genes is also diminished. Mass spectrometry analysis of proteins that co-immunoprecipitate with EcR and USP identified multiple Mediator subunits, including CDK8 and CycC. Consistently, CDK8-CycC interacts with EcR-USP in vivo; in particular, CDK8 and Med14 can directly interact with the AF1 domain of EcR. These results suggest that CDK8-CycC may serve as transcriptional cofactors for EcR-dependent transcription. During the larval–pupal transition, the levels of CDK8 protein positively correlate with EcR and USP levels, but inversely correlate with the activity of sterol regulatory element binding protein (SREBP), the master regulator of intracellular lipid homeostasis. Likewise, starvation of early third instar larvae precociously increases the levels of CDK8, EcR and USP, yet down-regulates SREBP activity. Conversely, refeeding the starved larvae strongly reduces CDK8 levels but increases SREBP activity. Importantly, these changes correlate with the timing for the larval–pupal transition. Taken together, these results suggest that CDK8-CycC links nutrient intake to developmental transitions (EcR activity) and fat metabolism (SREBP activity) during the larval–pupal transition. PMID:26222308

  20. Postsynaptic FMRP bidirectionally regulates excitatory synapses as a function of developmental age and MEF2 activity.

    PubMed

    Zang, Tong; Maksimova, Marina A; Cowan, Christopher W; Bassel-Duby, Rhonda; Olson, Eric N; Huber, Kimberly M

    2013-09-01

    Rates of synapse formation and elimination change over the course of postnatal development, but little is known of molecular mechanisms that mediate this developmental switch. Here, we report that the dendritic RNA-binding protein fragile X mental retardation protein (FMRP) bidirectionally and cell autonomously regulates excitatory synaptic function, which depends on developmental age as well as function of the activity-dependent transcription factor myocyte enhancer factor 2 (MEF2). The acute postsynaptic expression of FMRP in CA1 neurons of hippocampal slice cultures (during the first postnatal week, P6-P7) promotes synapse function and maturation. In contrast, the acute expression of FMRP or endogenous FMRP in more mature neurons (during the second postnatal week; P13-P16) suppresses synapse number. The ability of neuronal depolarization to stimulate MEF2 transcriptional activity increases over this same developmental period. Knockout of endogenous MEF2 isoforms causes acute postsynaptic FMRP expression to promote, instead of eliminate, synapses onto 2-week-old neurons. Conversely, the expression of active MEF2 in neonatal neurons results in a precocious FMRP-dependent synapse elimination. Our findings suggest that FMRP and MEF2 function together to fine tune synapse formation and elimination rates in response to neuronal activity levels over the course of postnatal development.

  1. Selection and analysis of cloned developmentally-regulated Dictyostelium discoideum genes by hybridization-competition.

    PubMed Central

    Mangiarotti, G; Chung, S; Zuker, C; Lodish, H F

    1981-01-01

    We describe a new technique for selection of cloned gene segments which are expressed preferentially at one developmental stage but at a relatively low level. A nitrocellulose filter replica of plaques of lambda phage which contain approximately 8 KB inserts of genomic DNA is prepared; it is hybridized with a small amount of [32p] labeled mRNA prepared from one developmental stage, in the presence of a several-hundred fold excess of competitor RNA from a different stage. We show that clones of Dictyostelium nuclear DNA which form hybrids under these conditions indeed encode developmentally regulated mRNAs. Our previous analysis of Dictyostelium discoideum differentiation indicated that transcripts from about 12% of the genome appear in mRNA at one defined stage of differentiation - the formation of cell-cell aggregates. A number of our new clones are novel, in that they encode multiple discrete mRNA species all of which accumulate only at the cell aggregate stages; others encode one or more mRNAs which appear at the tight aggregate stage and also one or more which are present throughout differentiation. These latter clones, in particular, would be difficult to identify using other selection techniques. Images PMID:7232208

  2. Prenatal tobacco exposure and self-regulation in early childhood: Implications for developmental psychopathology.

    PubMed

    Wiebe, Sandra A; Clark, Caron A C; De Jong, Desiree M; Chevalier, Nicolas; Espy, Kimberly Andrews; Wakschlag, Lauren

    2015-05-01

    Prenatal tobacco exposure (PTE) has a well-documented association with disruptive behavior in childhood, but the neurocognitive effects of exposure that underlie this link are not sufficiently understood. The present study was designed to address this gap, through longitudinal follow-up in early childhood of a prospectively enrolled cohort with well-characterized prenatal exposure. Three-year-old children (n = 151) were assessed using a developmentally sensitive battery capturing both cognitive and motivational aspects of self-regulation. PTE was related to motivational self-regulation, where children had to delay approach to attractive rewards, but not cognitive self-regulation, where children had to hold information in mind and inhibit prepotent motor responses. Furthermore, PTE predicted motivational self-regulation more strongly in boys than in girls, and when propensity scores were covaried to control for confounding risk factors, the effect of PTE on motivational self-regulation was significant only in boys. These findings suggest that PTE's impact on neurodevelopment may be greater in boys than in girls, perhaps reflecting vulnerability in neural circuits that subserve reward sensitivity and emotion regulation, and may also help to explain why PTE is more consistently related to disruptive behavior disorders than attention problems.

  3. Early developmental gene regulation in Strongylocentrotus purpuratus embryos in response to elevated CO₂ seawater conditions.

    PubMed

    Hammond, LaTisha M; Hofmann, Gretchen E

    2012-07-15

    Ocean acidification, or the increased uptake of CO(2) by the ocean due to elevated atmospheric CO(2) concentrations, may variably impact marine early life history stages, as they may be especially susceptible to changes in ocean chemistry. Investigating the regulatory mechanisms of early development in an environmental context, or ecological development, will contribute to increased understanding of potential organismal responses to such rapid, large-scale environmental changes. We examined transcript-level responses to elevated seawater CO(2) during gastrulation and the initiation of spiculogenesis, two crucial developmental processes in the purple sea urchin, Strongylocentrotus purpuratus. Embryos were reared at the current, accepted oceanic CO(2) concentration of 380 microatmospheres (μatm), and at the elevated levels of 1000 and 1350 μatm, simulating predictions for oceans and upwelling regions, respectively. The seven genes of interest comprised a subset of pathways in the primary mesenchyme cell gene regulatory network (PMC GRN) shown to be necessary for the regulation and execution of gastrulation and spiculogenesis. Of the seven genes, qPCR analysis indicated that elevated CO(2) concentrations only had a significant but subtle effect on two genes, one important for early embryo patterning, Wnt8, and the other an integral component in spiculogenesis and biomineralization, SM30b. Protein levels of another spicule matrix component, SM50, demonstrated significant variable responses to elevated CO(2). These data link the regulation of crucial early developmental processes with the environment that these embryos would be developing within, situating the study of organismal responses to ocean acidification in a developmental context.

  4. The GATA factor elt-1 regulates C. elegans developmental timing by promoting expression of the let-7 family microRNAs.

    PubMed

    Cohen, Max L; Kim, Sunhong; Morita, Kiyokazu; Kim, Seong Heon; Han, Min

    2015-03-01

    Postembryonic development in Caenorhabditis elegans is a powerful model for the study of the temporal regulation of development and for the roles of microRNAs in controlling gene expression. Stable switch-like changes in gene expression occur during development as stage-specific microRNAs are expressed and subsequently down-regulate other stage-specific factors, driving developmental progression. Key genes in this regulatory network are phylogenetically conserved and include the post-transcriptional microRNA repressor LIN-28; the nuclear hormone receptor DAF-12; and the microRNAs LIN-4, LET-7, and the three LET-7 family miRNAs (miR-48, miR-84, and miR-241). DAF-12 is known to regulate transcription of miR-48, miR-84 and miR-241, but its contribution is insufficient to account for all of the transcriptional regulation implied by the mutant phenotypes. In this work, the GATA-family transcription factor ELT-1 is identified from a genetic enhancer screen as a regulator of developmental timing in parallel to DAF-12, and is shown to do so by promoting the expression of the LET-7, miR-48, miR-84, and miR-241 microRNAs. The role of ELT-1 in developmental timing is shown to be separate from its role in cell-fate maintenance during post-embryonic development. In addition, analysis of Chromatin Immnoprecipitation (ChIP) data from the modENCODE project and this work suggest that the contribution of ELT-1 to the control of let-7 family microRNA expression is likely through direct transcription regulation.

  5. The GATA Factor elt-1 Regulates C. elegans Developmental Timing by Promoting Expression of the let-7 Family MicroRNAs

    PubMed Central

    Cohen, Max L.; Kim, Sunhong; Morita, Kiyokazu; Kim, Seong Heon; Han, Min

    2015-01-01

    Postembryonic development in Caenorhabditis elegans is a powerful model for the study of the temporal regulation of development and for the roles of microRNAs in controlling gene expression. Stable switch-like changes in gene expression occur during development as stage-specific microRNAs are expressed and subsequently down-regulate other stage-specific factors, driving developmental progression. Key genes in this regulatory network are phylogenetically conserved and include the post-transcriptional microRNA repressor LIN-28; the nuclear hormone receptor DAF-12; and the microRNAs LIN-4, LET-7, and the three LET-7 family miRNAs (miR-48, miR-84, and miR-241). DAF-12 is known to regulate transcription of miR-48, miR-84 and miR-241, but its contribution is insufficient to account for all of the transcriptional regulation implied by the mutant phenotypes. In this work, the GATA-family transcription factor ELT-1 is identified from a genetic enhancer screen as a regulator of developmental timing in parallel to DAF-12, and is shown to do so by promoting the expression of the LET-7, miR-48, miR-84, and miR-241 microRNAs. The role of ELT-1 in developmental timing is shown to be separate from its role in cell-fate maintenance during post-embryonic development. In addition, analysis of Chromatin Immnoprecipitation (ChIP) data from the modENCODE project and this work suggest that the contribution of ELT-1 to the control of let-7 family microRNA expression is likely through direct transcription regulation. PMID:25816370

  6. Self-Regulation and Math Attitudes: Effects on Academic Performance in Developmental Math Courses at a Community College

    ERIC Educational Resources Information Center

    Otts, Cynthia D.

    2010-01-01

    The purpose of the study was to investigate the relationship among math attitudes, self-regulated learning, and course outcomes in developmental math. Math attitudes involved perceived usefulness of math and math anxiety. Self-regulated learning represented the ability of students to control cognitive, metacognitive, and behavioral aspects of…

  7. Developmental regulation of insulin-like growth factor-I and growth hormone receptor gene expression.

    PubMed

    Shoba, L; An, M R; Frank, S J; Lowe, W L

    1999-06-25

    During development, the insulin-like growth factor I (IGF-I) gene is expressed in a tissue specific manner; however, the molecular mechanisms governing its developmental regulation remain poorly defined. To examine the hypothesis that expression of the growth hormone (GH) receptor accounts, in part, for the tissue specific expression of the IGF-I gene during development, the developmental regulation of IGF-I and GH receptor gene expression in rat tissues was examined. The level of IGF-I and GH receptor mRNA was quantified in RNA prepared from rats between day 17 of gestation (E17) and 17 months of age (17M) using an RNase protection assay. Developmental regulation of IGF-I gene expression was tissue specific with four different patterns of expression seen. In liver, IGF-I mRNA levels increased markedly between E17 and postnatal day 45 (P45) and declined thereafter. In contrast, in brain, skeletal muscle and testis, IGF-I mRNA levels decreased between P5 and 4M but were relatively unchanged thereafter. In heart and kidney, a small increase in IGF-I mRNA levels was observed between the early postnatal period and 4 months, whereas in lung, minimal changes were observed during development. The changes in GH receptor mRNA levels were, in general, coordinate with the changes in IGF-I mRNA levels, except in skeletal muscle. Interestingly, quantification of GH receptor levels by Western blot analysis in skeletal muscle demonstrated changes coordinate with IGF-I mRNA levels. The levels of the proteins which mediate GH receptor signaling (STAT1, -3, and -5, and JAK2) were quantified by Western blot analysis. These proteins also are expressed in a tissue specific manner during development. In some cases, the pattern of expression was coordinate with IGF-I gene expression, whereas in others it was discordant. To further define molecular mechanisms for the developmental regulation of IGF-I gene expression, protein binding to IGFI-FP1, a protein binding site that is in the major

  8. A co-expression gene network associated with developmental regulation of apple fruit acidity.

    PubMed

    Bai, Yang; Dougherty, Laura; Cheng, Lailiang; Xu, Kenong

    2015-08-01

    Apple fruit acidity, which affects the fruit's overall taste and flavor to a large extent, is primarily determined by the concentration of malic acid. Previous studies demonstrated that the major QTL malic acid (Ma) on chromosome 16 is largely responsible for fruit acidity variations in apple. Recent advances suggested that a natural mutation that gives rise to a premature stop codon in one of the two aluminum-activated malate transporter (ALMT)-like genes (called Ma1) is the genetic causal element underlying Ma. However, the natural mutation does not explain the developmental changes of fruit malate levels in a given genotype. Using RNA-seq data from the fruit of 'Golden Delicious' taken at 14 developmental stages from 1 week after full-bloom (WAF01) to harvest (WAF20), we characterized their transcriptomes in groups of high (12.2 ± 1.6 mg/g fw, WAF03-WAF08), mid (7.4 ± 0.5 mg/g fw, WAF01-WAF02 and WAF10-WAF14) and low (5.4 ± 0.4 mg/g fw, WAF16-WAF20) malate concentrations. Detailed analyses showed that a set of 3,066 genes (including Ma1) were expressed not only differentially (P FDR < 0.05) between the high and low malate groups (or between the early and late developmental stages) but also in significant (P < 0.05) correlation with malate concentrations. The 3,066 genes fell in 648 MapMan (sub-) bins or functional classes, and 19 of them were significantly (P FDR < 0.05) co-enriched or co-suppressed in a malate dependent manner. Network inferring using the 363 genes encompassed in the 19 (sub-) bins, identified a major co-expression network of 239 genes. Since the 239 genes were also differentially expressed between the early (WAF03-WAF08) and late (WAF16-WAF20) developmental stages, the major network was considered to be associated with developmental regulation of apple fruit acidity in 'Golden Delicious'.

  9. Developmental effects of antiepileptic drugs and the need for improved regulations

    PubMed Central

    Loring, David W.

    2016-01-01

    Antiepileptic drugs (AEDs) are among the most common teratogenic drugs prescribed to women of childbearing age. AEDs can induce both anatomical (malformations) and behavioral (cognitive/behavioral deficits) teratogenicity. Only in the last decade have we begun to truly discriminate differential AED developmental effects. Fetal valproate exposure carries a special risk for both anatomical and behavioral teratogenic abnormalities, but the mechanisms and reasons for individual variability are unknown. Intermediate anatomical risks exist for phenobarbital and topiramate. Several AEDs (e.g., lamotrigine and levetiracetam) appear to possess low risks for both anatomical and behavioral teratogenesis. Despite advances in the past decade, our knowledge of the teratogenic risks for most AEDs and the underlying mechanisms remain inadequate. Further, the long-term effects of AEDs in neonates and older children remain uncertain. The pace of progress is slow given the lifelong consequences of diminished developmental outcomes, exposing children unnecessarily to potential adverse effects. It is imperative that new approaches be employed to determine risks more expediently. Our recommendations include a national reporting system for congenital malformations, federal funding of the North American AED Pregnancy Registry, routine meta-analyses of cohort studies to detect teratogenic signals, monitoring of AED prescription practices for women, routine preclinical testing of all new AEDs for neurodevelopmental effects, more specific Food and Drug Administration requirements to establish differential AED cognitive effects in children, and improved funding of basic and clinical research to fully delineate risks and underlying mechanisms for AED-induced anatomical and behavioral teratogenesis. PMID:26519545

  10. INHIBITION OF FATTY ACID DESATURASES IN Drosophila melanogaster LARVAE BLOCKS FEEDING AND DEVELOPMENTAL PROGRESSION.

    PubMed

    Wang, Yiwen; da Cruz, Tina Correia; Pulfemuller, Alicia; Grégoire, Stéphane; Ferveur, Jean-François; Moussian, Bernard

    2016-05-01

    Fatty acid desaturases are metabolic setscrews. To study their systemic impact on growth in Drosophila melanogaster, we inhibited fatty acid desaturases using the inhibitor CAY10566. As expected, the amount of desaturated lipids is reduced in larvae fed with CAY10566. These animals cease feeding soon after hatching, and their growth is strongly attenuated. A starvation program is not launched, but the expression of distinct metabolic genes is activated, possibly to mobilize storage material. Without attaining the normal size, inhibitor-fed larvae molt to the next stage indicating that the steroid hormone ecdysone triggers molting correctly. Nevertheless, after molting, expression of ecdysone-dependent regulators is not induced. While control larvae molt a second time, these larvae fail to do so and die after few days of straying. These effects are similar to those observed in experiments using larvae deficient for the fatty acid desaturase1 gene. Based on these data, we propose that the ratio of saturated to unsaturated fatty acids adjusts a sensor system that directs feeding behavior. We also hypothesize that loss of fatty acid desaturase activity leads to a block of the genetic program of development progression indirectly by switching on a metabolic compensation program.

  11. Peer victimization in adolescence: The nature, progression, and consequences of being bullied within a developmental context.

    PubMed

    Troop-Gordon, Wendy

    2017-02-01

    Since Dan Olweus's seminal work on bullying in the 1970's (Olweus, 1978), there has been a concerted effort by investigators to identify the confluence of factors that contribute to peer victimization and its role in psychosocial development. Although the cause and consequences of peer victimization may include underlying, age-invariant processes, the manifestation of these factors is, in part, driven by the developmental stage being studied. Thus, a comprehensive understanding of peer victimization requires an explicit developmental perspective. This paper examines how peer victimization in adolescence is unique from other developmental periods. Changes in the nature of peer victimization, associated risk factors, the contexts in which victimization is experienced, and the psychosocial outcomes affected are addressed. A primary focus is how maturational processes and interpersonal contexts characteristic of adolescence contribute to changes in victimization, with the objective of informing future research directions and the development of effective interventions.

  12. Developmental stage-specific regulation of the circadian clock by temperature in zebrafish.

    PubMed

    Lahiri, Kajori; Froehlich, Nadine; Heyd, Andreas; Foulkes, Nicholas S; Vallone, Daniela

    2014-01-01

    The circadian clock enables animals to adapt their physiology and behaviour in anticipation of the day-night cycle. Light and temperature represent two key environmental timing cues (zeitgebers) able to reset this mechanism and so maintain its synchronization with the environmental cycle. One key challenge is to unravel how the regulation of the clock by zeitgebers matures during early development. The zebrafish is an ideal model for studying circadian clock ontogeny since the process of development occurs ex utero in an optically transparent chorion and many tools are available for genetic analysis. However, the role played by temperature in regulating the clock during zebrafish development is poorly understood. Here, we have established a clock-regulated luciferase reporter transgenic zebrafish line (Tg (-3.1) per1b::luc) to study the effects of temperature on clock entrainment. We reveal that under complete darkness, from an early developmental stage onwards (48 to 72 hpf), exposure to temperature cycles is a prerequisite for the establishment of self-sustaining rhythms of zfper1b, zfaanat2, and zfirbp expression and also for circadian cell cycle rhythms. Furthermore, we show that following the 5-9 somite stage, the expression of zfper1b is regulated by acute temperature shifts.

  13. ATRX: A novel progesterone regulated biomarker of mammalian oocyte developmental potential.

    PubMed

    O'Shea, Lynne Clare; Daly, Edward; Hensey, Carmel; Fair, Trudee

    2017-03-01

    A multi-species meta-analysis of published transcriptomic data from models of oocyte competence identified the chromatin remodelling factor ATRX, as a putative biomarker of oocyte competence. The objective of the current study was to test the hypothesis that ATRX protein expression by cumulus oocyte complexes (COCs) reflects their intrinsic quality and developmental potential. In excess of 10,000 bovine COCs were utilized to test our hypothesis. COCs were in vitro matured (IVM) under conditions associated with reduced developmental potential: IVM in the presence or absence of (1) progesterone synthesis inhibitor (Trilostane); (2) nuclear progesterone receptor inhibitor (Aglepristone) or (3) an inducer of DNA damage (Staurosporine). ATRX protein expression and localization were determined using immunocytochemistry and Western blot analysis. A proportion of COCs matured in the presence or absence of Trilostane were in vitro fertilised and cultured, with subsequent embryo development characteristics analysed. In addition, ATRX expression was investigated in 40 human germinal vesicle stage COCs. Our results showed that ATRX is expressed in human and bovine germinal vesicle oocytes and cumulus cells. In bovine, expression decreases following IVM. However, this decline is not observed in COCs matured under sub-optimal conditions. Blastocyst development rate and cell number are decreased, whereas the incidence of abnormal metaphase phase spindle and chromosome alignment are increased, following IVM in the presence of Trilostane (P < 0.05). In conclusion, localization of ATRX to the cumulus cell nuclei and oocyte chromatin, post IVM, is associated with poor oocyte quality and low developmental potential. Furthermore, ATRX is dynamically regulated in response to progesterone signalling.

  14. DRG1 is a potential oncogene in lung adenocarcinoma and promotes tumor progression via spindle checkpoint signaling regulation

    PubMed Central

    Lu, Li; Lv, Yanrong; Dong, Ji; Hu, Shaohua; Peng, Ruiyun

    2016-01-01

    Developmentally regulated GTP binding protein 1 (DRG1), a member of the DRG family, plays important roles in regulating cell growth. However, the molecular basis of DRG1 in cell proliferation regulation and the relationship between DRG1 and tumor progression remain poorly understood. Here, we demonstrate that DRG1 is elevated in lung adenocarcinomas while weakly expressed in adjacent lung tissues. DRG1 knockdown causes growth inhibition of tumor cells by significantly increasing the proportion of cells in M phase. Overexpression of DRG1 leads to chromosome missegregation which is an important index for tumorigenesis. Interestingly, ectopic of DRG1 reduces taxol induced apoptosis of lung adenocarcinoma cells. Mechanistic analyses confirm that DRG1 localizes at mitotic spindles in dividing cells and binds to spindle checkpoint signaling proteins in vivo. These studies highlight the expanding role of DRG1 in tumorigenesis and reveal a mechanism of DRG1 in taxol resistance. PMID:27626498

  15. Possible deletion of a developmentally regulated heavy-chain variable region gene in autoimmune diseases

    SciTech Connect

    Yang, Pei-Ming; Olee, Tsaiwei; Kozin, F.; Carson, D.A.; Chen, P.P. ); Olsen, N.J. ); Siminovitch, K.A. )

    1990-10-01

    Several autoantibody-associated variable region (V) genes are preferentially expressed during early ontogenic development, suggesting strongly that they are of developmental and physiological importance. As such, it is possible that polymorphisms in one or more of these genes may alter susceptibility to autoimmune disease. The authors have searched extensively for a probe related to a developmentally regulated V gene that has the power to differentiate among highly homologous V genes in human populations. Using such a probe (i.e., Humhv3005/P1) related to both anti-DNA and anti-IgG autoantibodies, they studied restriction fragment length polymorphisms in patients with rheumatoid arthritis and systemic lupus erythematosus and found an apparent heavy-chain V (V{sub H}) gene deletion that was nearly restricted to the autoimmune patients. These data suggest that deletions of physiologically important V{sub H} genes may increase the risk of autoimmunity through indirect effects on the development and homeostasis of the B-cell repertoire.

  16. Developmental role for endocannabinoid signaling in regulating glucose metabolism and growth.

    PubMed

    Li, Zhiying; Schmidt, Sarah F; Friedman, Jeffrey M

    2013-07-01

    Treatment of ob/ob (obese) mice with a cannabinoid receptor 1 (Cnr1) antagonist reduces food intake, suggesting a role for endocannabinoid signaling in leptin action. We further evaluated the role of endocannabinoid signaling by analyzing the phenotype of Cnr1 knockout ob/ob mice. Double mutant animals show a more severe growth retardation than ob/ob mice with similar levels of adiposity and reduced IGF-I levels without alterations of growth hormone (GH) levels. The double mutant mice are also significantly more glucose intolerant than ob/ob mice. This is in contrast to treatment of ob/ob mice with a Cnr1 antagonist that had no effect on glucose metabolism, suggesting a possible requirement for endocannabinoid signaling during development for normal glucose homeostasis. Double mutant animals also showed similar leptin sensitivity as ob/ob mice, suggesting that there are developmental changes that compensate for the loss of Cnr1 signaling. These data establish a role for Cnr1 during development and suggest that compensatory changes during development may mitigate the requirement for Cnr1 in mediating the effects of leptin. The data also suggest a developmental role for Cnr1 to promote growth, regulate the GH/IGF-I axis, and improve β-cell function and glucose homeostasis in the setting of leptin deficiency.

  17. ETOILE regulates developmental patterning in the filamentous brown alga Ectocarpus siliculosus.

    PubMed

    Le Bail, Aude; Billoud, Bernard; Le Panse, Sophie; Chenivesse, Sabine; Charrier, Bénédicte

    2011-04-01

    Brown algae are multicellular marine organisms evolutionarily distant from both metazoans and land plants. The molecular or cellular mechanisms that govern the developmental patterning in brown algae are poorly characterized. Here, we report the first morphogenetic mutant, étoile (etl), produced in the brown algal model Ectocarpus siliculosus. Genetic, cellular, and morphometric analyses showed that a single recessive locus, ETL, regulates cell differentiation: etl cells display thickening of the extracellular matrix (ECM), and the elongated, apical, and actively dividing E cells are underrepresented. As a result of this defect, the overrepresentation of round, branch-initiating R cells in the etl mutant leads to the rapid induction of the branching process at the expense of the uniaxial growth in the primary filament. Computational modeling allowed the simulation of the etl mutant phenotype by including a modified response to the neighborhood information in the division rules used to specify wild-type development. Microarray experiments supported the hypothesis of a defect in cell-cell communication, as primarily Lin-Notch-domain transmembrane proteins, which share similarities with metazoan Notch proteins involved in binary cell differentiation were repressed in etl. Thus, our study highlights the role of the ECM and of novel transmembrane proteins in cell-cell communication during the establishment of the developmental pattern in this brown alga.

  18. Tandemly repeated exons encode 81-base repeats in multiple, developmentally regulated Schistosoma mansoni transcripts.

    PubMed Central

    Davis, R E; Davis, A H; Carroll, S M; Rajkovic, A; Rottman, F M

    1988-01-01

    The adult Schistosoma mansoni cDNA clone 10-3 encodes an antigen that is recognized by sera from infected humans. We characterized multiple developmentally regulated transcripts homologous to the 10-3 cDNA and portions of the complex genomic loci encoding those transcripts. Transcripts of approximately 950, 870, and 780 nucleotides were expressed in adults, whereas only the 780-nucleotide transcript was observed in the larval stage. These transcripts were highly similar, containing variable numbers of identical direct tandem repeats of 81 bases. Although the sequence of the repeating elements and sequences 3' to them were identical in all the transcripts, sequences 5' of the repeating elements exhibited variations, including a 27-base insertion, alternative start sites for transcription, and alternate 5' exon usage. These transcripts appeared to be derived in part by the developmentally controlled alternative splicing of small exons and the use of alternative transcription initiation sites from the one or two complex loci of at least 40 kilobase pairs. Each 81-base repeat in the transcripts was encoded by three dispersed 27-base-pair exons. These 27-base-pair exons were contained within highly conserved, reiterated 3-kilobase-pair genomic tandem arrays. Images PMID:3211127

  19. The early embryo response to intracellular reactive oxygen species is developmentally regulated.

    PubMed

    Bain, Nathan T; Madan, Pavneesh; Betts, Dean H

    2011-01-01

    In vitro embryo production (IVP) suffers from excessive developmental failure. Its inefficiency is linked, in part, to reactive oxygen species (ROS) brought on by high ex vivo oxygen (O(2)) tensions. To further delineate the effects of ROS on IVP, the intracellular ROS levels of early bovine embryos were modulated by: (1) varying O(2) tension; (2) exogenous H(2)O(2) treatment; and (3) antioxidant supplementation. Although O(2) tension did not significantly affect blastocyst frequencies (P>0.05), 20% O(2) accelerated the rate of first cleavage division and significantly decreased and increased the proportion of permanently arrested 2- to 4-cell embryos and apoptotic 9- to 16-cell embryos, respectively, compared with embryos cultured in 5% O(2) tension. Treatment with H(2)O(2), when applied separately to oocytes, zygotes, 2- to 4-cell embryos or 9- to 16-cell embryos, resulted in a significant (P<0.05) dose-dependent decrease in blastocyst development in conjunction with a corresponding increase in the induction of either permanent embryo arrest or apoptosis in a stage-dependent manner. Polyethylene glycol-catalase supplementation reduced ROS-induced embryo arrest and/or death, resulting in a significant (P<0.05) increase in blastocyst frequencies under high O(2) culture conditions. Together, these results indicate that intracellular ROS may be signalling molecules that, outside an optimal range, result in various developmentally regulated modes of embryo demise.

  20. Analysis of genes developmentally regulated during storage root formation of sweet potato.

    PubMed

    Tanaka, Masaru; Takahata, Yasuhiro; Nakatani, Makoto

    2005-01-01

    To identify the genes involved in storage root formation of sweet potato (Ipomoea batatas), we performed a simplified differential display analysis on adventitious roots at different developmental stages of the storage root. The expression patterns were confirmed by semiquantitative RT-PCR analyses. As a result, 10 genes were identified as being developmentally regulated and were named SRF1-SRF10. The expression of SRF1, SRF2, SRF3, SRF5, SRF6, SRF7, and SRF9 increased during storage root formation, whereas the expression of SRF4, SRF8, and SRF10 decreased. For further characterization, a full-length cDNA of SRF6 was isolated from the cDNA library of the storage root. SRF6 encoded a receptor-like kinase (RLK), which was structurally similar to the leucine-rich repeat (LRR) II RLK family of Arabidopsis thaliana. RNA gel blot analysis showed that the mRNA of SRF6 was most abundantly expressed in the storage roots, although a certain amount of expression was also observed in other vegetative organs. Tissue print mRNA blot analysis of the storage root showed that the mRNA of SRF6 was localized around the primary cambium and meristems in the xylem, which consist of actively dividing cells and cause the thickening of the storage root.

  1. The microRNA bantam regulates a developmental transition in epithelial cells that restricts sensory dendrite growth.

    PubMed

    Jiang, Nan; Soba, Peter; Parker, Edward; Kim, Charles C; Parrish, Jay Z

    2014-07-01

    As animals grow, many early born structures grow by cell expansion rather than cell addition; thus growth of distinct structures must be coordinated to maintain proportionality. This phenomenon is particularly widespread in the nervous system, with dendrite arbors of many neurons expanding in concert with their substrate to sustain connectivity and maintain receptive field coverage as animals grow. After rapidly growing to establish body wall coverage, dendrites of Drosophila class IV dendrite arborization (C4da) neurons grow synchronously with their substrate, the body wall epithelium, providing a system to study how proportionality is maintained during animal growth. Here, we show that the microRNA bantam (ban) ensures coordinated growth of C4da dendrites and the epithelium through regulation of epithelial endoreplication, a modified cell cycle that entails genome amplification without cell division. In Drosophila larvae, epithelial endoreplication leads to progressive changes in dendrite-extracellular matrix (ECM) and dendrite-epithelium contacts, coupling dendrite/substrate expansion and restricting dendrite growth beyond established boundaries. Moreover, changes in epithelial expression of cell adhesion molecules, including the beta-integrin myospheroid (mys), accompany this developmental transition. Finally, endoreplication and the accompanying changes in epithelial mys expression are required to constrain late-stage dendrite growth and structural plasticity. Hence, modulating epithelium-ECM attachment probably influences substrate permissivity for dendrite growth and contributes to the dendrite-substrate coupling that ensures proportional expansion of the two cell types.

  2. From Premack to PECS: 25 Years of Progress in Communication Intervention for Individuals with Developmental Disabilities

    ERIC Educational Resources Information Center

    Sigafoos, Jeff

    2005-01-01

    Educational and behavioural psychologists have made major contributions to the field of communication intervention for individuals with developmental and physical disabilities. A brief personal perspective is provided on some of the major works and contributors that have shaped the field over the past 25 years. Major contributions and personal…

  3. Genotypically Identifying Wheat Mesophyll Conductance Regulation under Progressive Drought Stress

    PubMed Central

    Olsovska, Katarina; Kovar, Marek; Brestic, Marian; Zivcak, Marek; Slamka, Pavol; Shao, Hong Bo

    2016-01-01

    Photosynthesis limitation by CO2 flow constraints from sub-stomatal cavities to carboxylation sites in chloroplasts under drought stress conditions is, at least in some plant species or crops not fully understood, yet. Leaf mesophyll conductance for CO2 (gm) may considerably affect both photosynthesis and water use efficiency (WUE) in plants under drought conditions. The aim of our study was to detect the responses of gm in leaves of four winter wheat (Triticum aestivum L.) genotypes from different origins under long-term progressive drought. Based on the measurement of gas-exchange parameters the variability of genotypic responses was analyzed at stomatal (stomata closure) and non-stomatal (diffusional and biochemical) limits of net CO2 assimilation rate (AN). In general, progressive drought caused an increasing leaf diffusion resistance against CO2 flow leading to the decrease of AN, gm and stomatal conductance (gs), respectively. Reduction of gm also led to inhibition of carboxylation efficiency (Vcmax). On the basis of achieved results a strong positive relationship between gm and gs was found out indicating a co-regulation and mutual independence of the relationship under the drought conditions. In severely stressed plants, the stomatal limitation of the CO2 assimilation rate was progressively increased, but to a less extent in comparison to gm, while a non-stomatal limitation became more dominant due to the prolonged drought. Mesophyll conductance (gm) seems to be a suitable mechanism and parameter for selection of improved diffusional properties and photosynthetic carbon assimilation in C3 plants, thus explaining their better photosynthetic performance at a whole plant level during periods of drought. PMID:27551283

  4. Histone supply regulates S phase timing and cell cycle progression

    PubMed Central

    Günesdogan, Ufuk; Jäckle, Herbert; Herzig, Alf

    2014-01-01

    Eukaryotes package DNA into nucleosomes that contain a core of histone proteins. During DNA replication, nucleosomes are disrupted and re-assembled with newly synthesized histones and DNA. Despite much progress, it is still unclear why higher eukaryotes contain multiple core histone genes, how chromatin assembly is controlled, and how these processes are coordinated with cell cycle progression. We used a histone null mutation of Drosophila melanogaster to show that histone supply levels, provided by a defined number of transgenic histone genes, regulate the length of S phase during the cell cycle. Lack of de novo histone supply not only extends S phase, but also causes a cell cycle arrest during G2 phase, and thus prevents cells from entering mitosis. Our results suggest a novel cell cycle surveillance mechanism that monitors nucleosome assembly without involving the DNA repair pathways and exerts its effect via suppression of CDC25 phosphatase String expression. DOI: http://dx.doi.org/10.7554/eLife.02443.001 PMID:25205668

  5. Cells of a common developmental origin regulate REM/non-REM sleep and wakefulness in mice.

    PubMed

    Hayashi, Yu; Kashiwagi, Mitsuaki; Yasuda, Kosuke; Ando, Reiko; Kanuka, Mika; Sakai, Kazuya; Itohara, Shigeyoshi

    2015-11-20

    Mammalian sleep comprises rapid eye movement (REM) sleep and non-REM (NREM) sleep. To functionally isolate from the complex mixture of neurons populating the brainstem pons those involved in switching between REM and NREM sleep, we chemogenetically manipulated neurons of a specific embryonic cell lineage in mice. We identified excitatory glutamatergic neurons that inhibit REM sleep and promote NREM sleep. These neurons shared a common developmental origin with neurons promoting wakefulness; both derived from a pool of proneural hindbrain cells expressing Atoh1 at embryonic day 10.5. We also identified inhibitory γ-aminobutyric acid-releasing neurons that act downstream to inhibit REM sleep. Artificial reduction or prolongation of REM sleep in turn affected slow-wave activity during subsequent NREM sleep, implicating REM sleep in the regulation of NREM sleep.

  6. Light and developmental regulation of the Anp-controlled anthocyanin phenotype of bean pods.

    PubMed

    Gantet, P; Bettini, P; Dron, M

    1993-10-01

    In the presence of the dominant allele of the Anp gene, bean pods present a purple-mottled phenotype. The purple pigmentation is variable from cell to cell in the pod epidermal layer and develops as a random mosaic. Three anthocyanidins, delphinidin, petunidin and malvidin, are involved in this purple pigmentation. Anthocyanins accumulated in vacuoles; anthocyanoplasts and cristal bodies were also observed occasionally. A developmental switch is a prerequisite for anthocyanin accumulation in the pods. This does not occur before day 4 after pollination and is controlled by light in competent pods. mRNAs for PAL, CHS, CHI, DFR and UFGT are induced in the pods, indicating that the general anthocyanin biosynthetic pathway is well conserved at both the biochemical and molecular levels in this species. mRNA steady-state level studies of PAL and CHS suggest that the light regulation occurs at the transcriptional level.

  7. A developmentally regulated MAP kinase activated by hydration in tobacco pollen.

    PubMed Central

    Wilson, C; Voronin, V; Touraev, A; Vicente, O; Heberle-Bors, E

    1997-01-01

    A novel mitogen-activated protein (MAP) kinase signaling pathway has been identified in tobacco. This pathway is developmentally regulated during pollen maturation and is activated by hydration during pollen germination. Analysis of different stages of pollen development showed that transcriptional and translational induction of MAP kinase synthesis occurs at the mid-bicellular stage of pollen maturation. However, the MAP kinase is stored in an inactive form in the mature, dry pollen grain. Kinase activation is very rapid after hydration of the dry pollen, peaking at approximately 5 min and decreasing thereafter. Immunoprecipitation of the kinase activity by an anti-phosphotyrosine antibody is consistent with the activation of a MAP kinase. The kinetics of activation suggest that the MAP kinase plays a role in the activation of the pollen grain after hydration rather than in pollen tube growth. PMID:9401129

  8. Retinoic acid is enriched in Hensen's node and is developmentally regulated in the early chicken embryo.

    PubMed Central

    Chen, Y; Huang, L; Russo, A F; Solursh, M

    1992-01-01

    Retinoic acid (RA) has been considered as a potential morphogen in the chicken limb and has also been suggested to be involved in early embryonic development. On the basis of biological activity, previous reports suggest that Hensen's node, the anatomical equivalent in the chicken of the Spemann's organizer, may contain RA. Here, by using a molecular assay system, we demonstrate that Hensen's node contains retinoids in a concentration approximately 20 times more than that in the neighboring tissues. Furthermore, stage 6 Hensen's node contains approximately 3 times more retinoid than that of stage 4 embryos. These endogenous retinoids may establish a concentration gradient from Hensen's node to adjacent tissues and play a role in establishing the primary embryonic axis in the vertebrate. The results also suggest that the retinoid concentration in Hensen's node is developmentally regulated. Images PMID:1438194

  9. Retinoic acid is enriched in Hensen's node and is developmentally regulated in the early chicken embryo.

    PubMed

    Chen, Y; Huang, L; Russo, A F; Solursh, M

    1992-11-01

    Retinoic acid (RA) has been considered as a potential morphogen in the chicken limb and has also been suggested to be involved in early embryonic development. On the basis of biological activity, previous reports suggest that Hensen's node, the anatomical equivalent in the chicken of the Spemann's organizer, may contain RA. Here, by using a molecular assay system, we demonstrate that Hensen's node contains retinoids in a concentration approximately 20 times more than that in the neighboring tissues. Furthermore, stage 6 Hensen's node contains approximately 3 times more retinoid than that of stage 4 embryos. These endogenous retinoids may establish a concentration gradient from Hensen's node to adjacent tissues and play a role in establishing the primary embryonic axis in the vertebrate. The results also suggest that the retinoid concentration in Hensen's node is developmentally regulated.

  10. Interpersonal Stress Regulation and the Development of Anxiety Disorders: An Attachment-Based Developmental Framework

    PubMed Central

    Nolte, Tobias; Guiney, Jo; Fonagy, Peter; Mayes, Linda C.; Luyten, Patrick

    2011-01-01

    Anxiety disorders represent a common but often debilitating form of psychopathology in both children and adults. While there is a growing understanding of the etiology and maintenance of these disorders across various research domains, only recently have integrative accounts been proposed. While classical attachment history has been a traditional core construct in psychological models of anxiety, contemporary attachment theory has the potential to integrate neurobiological and behavioral findings within a multidisciplinary developmental framework. The current paper proposes a modern attachment theory-based developmental model grounded in relevant literature from multiple disciplines including social neuroscience, genetics, neuroendocrinology, and the study of family factors involved in the development of anxiety disorders. Recent accounts of stress regulation have highlighted the interplay between stress, anxiety, and activation of the attachment system. This interplay directly affects the development of social–cognitive and mentalizing capacities that are acquired in the interpersonal context of early attachment relationships. Early attachment experiences are conceptualized as the key organizer of a complex interplay between genetic, environmental, and epigenetic contributions to the development of anxiety disorders – a multifactorial etiology resulting from dysfunctional co-regulation of fear and stress states. These risk-conferring processes are characterized by hyperactivation strategies in the face of anxiety. The cumulative allostatic load and subsequent “wear and tear” effects associated with hyperactivation strategies converge on the neural pathways of anxiety and stress. Attachment experiences further influence the development of anxiety as potential moderators of risk factors, differentially impacting on genetic vulnerability and relevant neurobiological pathways. Implications for further research and potential treatments are outlined. PMID

  11. Interpersonal stress regulation and the development of anxiety disorders: an attachment-based developmental framework.

    PubMed

    Nolte, Tobias; Guiney, Jo; Fonagy, Peter; Mayes, Linda C; Luyten, Patrick

    2011-01-01

    Anxiety disorders represent a common but often debilitating form of psychopathology in both children and adults. While there is a growing understanding of the etiology and maintenance of these disorders across various research domains, only recently have integrative accounts been proposed. While classical attachment history has been a traditional core construct in psychological models of anxiety, contemporary attachment theory has the potential to integrate neurobiological and behavioral findings within a multidisciplinary developmental framework. The current paper proposes a modern attachment theory-based developmental model grounded in relevant literature from multiple disciplines including social neuroscience, genetics, neuroendocrinology, and the study of family factors involved in the development of anxiety disorders. Recent accounts of stress regulation have highlighted the interplay between stress, anxiety, and activation of the attachment system. This interplay directly affects the development of social-cognitive and mentalizing capacities that are acquired in the interpersonal context of early attachment relationships. Early attachment experiences are conceptualized as the key organizer of a complex interplay between genetic, environmental, and epigenetic contributions to the development of anxiety disorders - a multifactorial etiology resulting from dysfunctional co-regulation of fear and stress states. These risk-conferring processes are characterized by hyperactivation strategies in the face of anxiety. The cumulative allostatic load and subsequent "wear and tear" effects associated with hyperactivation strategies converge on the neural pathways of anxiety and stress. Attachment experiences further influence the development of anxiety as potential moderators of risk factors, differentially impacting on genetic vulnerability and relevant neurobiological pathways. Implications for further research and potential treatments are outlined.

  12. Driving skills of young adults with developmental coordination disorder: regulating speed and coping with distraction.

    PubMed

    de Oliveira, Rita F; Wann, John P

    2011-01-01

    In two experiments, we used an automatic car simulator to examine the steering control, speed regulation and response to hazards of young adults with developmental coordination disorder (DCD) and limited driving experience. In Experiment 1 participants either used the accelerator pedal to regulate their speed, or used the brake pedal when they needed to slow down from a pre-set speed. In Experiment 2, we introduced an auditory distraction condition that shared similarities with maintaining a conversation. Overall, the DCD group produced a larger variance in heading and needed more steering adjustments on straight roads, compared to age-matched controls. When turning bends, the DCD group showed greater difficulty in controlling steering while regulating their speed with the accelerator pedal but this was less problematic when using the brake. The DCD group also responded slower than the control group to pedestrians who walked towards their path. The auditory distraction in Experiment 2 had no visible effects on steering control but increased the reaction times to pedestrians in both groups. We discuss the results in terms of the visuomotor control in steering and the learning of optimal mappings between optic flow and vehicle control.

  13. Genetic interaction of PGE2 and Wnt signaling regulates developmental specification of stem cells and regeneration

    PubMed Central

    Goessling, Wolfram; North, Trista E.; Loewer, Sabine; Lord, Allegra M.; Lee, Sang; Stoick-Cooper, Cristi L.; Weidinger, Gilbert; Puder, Mark; Daley, George Q.; Moon, Randall T.; Zon, Leonard I.

    2009-01-01

    Summary Interactions between developmental signaling pathways govern the formation and function of stem cells. Prostaglandin (PG) E2 regulates vertebrate hematopoietic stem cells (HSC). Similarly, the Wnt signaling pathway controls HSC self-renewal and bone marrow repopulation. Here, we show that wnt reporter activity in zebrafish HSCs is responsive to PGE2 modulation, demonstrating a direct interaction in vivo. Inhibition of PGE2 synthesis blocked wnt-induced alterations in HSC formation. PGE2 modified the wnt signaling cascade at the level of β-catenin degradation through cAMP/PKA-mediated stabilizing phosphorylation events. The PGE2/Wnt interaction regulated murine stem and progenitor populations in vitro in hematopoietic ES cell assays and in vivo following transplantation. The relationship between PGE2 and Wnt was also conserved during regeneration of other organ systems. Our work provides the first in vivo evidence that Wnt activation in stem cells requires PGE2, and suggests the PGE2/Wnt interaction is a master regulator of vertebrate regeneration and recovery. PMID:19303855

  14. REN: a novel, developmentally regulated gene that promotes neural cell differentiation.

    PubMed

    Gallo, Rita; Zazzeroni, Francesca; Alesse, Edoardo; Mincione, Claudia; Borello, Ugo; Buanne, Pasquale; D'Eugenio, Roberta; Mackay, Andrew R; Argenti, Beatrice; Gradini, Roberto; Russo, Matteo A; Maroder, Marella; Cossu, Giulio; Frati, Luigi; Screpanti, Isabella; Gulino, Alberto

    2002-08-19

    Expansion and fate choice of pluripotent stem cells along the neuroectodermal lineage is regulated by a number of signals, including EGF, retinoic acid, and NGF, which also control the proliferation and differentiation of central nervous system (CNS) and peripheral nervous system (PNS) neural progenitor cells. We report here the identification of a novel gene, REN, upregulated by neurogenic signals (retinoic acid, EGF, and NGF) in pluripotent embryonal stem (ES) cells and neural progenitor cell lines in association with neurotypic differentiation. Consistent with a role in neural promotion, REN overexpression induced neuronal differentiation as well as growth arrest and p27Kip1 expression in CNS and PNS neural progenitor cell lines, and its inhibition impaired retinoic acid induction of neurogenin-1 and NeuroD expression. REN expression is developmentally regulated, initially detected in the neural fold epithelium of the mouse embryo during gastrulation, and subsequently throughout the ventral neural tube, the outer layer of the ventricular encephalic neuroepithelium and in neural crest derivatives including dorsal root ganglia. We propose that REN represents a novel component of the neurogenic signaling cascade induced by retinoic acid, EGF, and NGF, and is both a marker and a regulator of neuronal differentiation.

  15. Apoplastic and intracellular plant sugars regulate developmental transitions in witches' broom disease of cacao.

    PubMed

    Barau, Joan; Grandis, Adriana; Carvalho, Vinicius Miessler de Andrade; Teixeira, Gleidson Silva; Zaparoli, Gustavo Henrique Alcalá; do Rio, Maria Carolina Scatolin; Rincones, Johana; Buckeridge, Marcos Silveira; Pereira, Gonçalo Amarante Guimarães

    2015-03-01

    Witches' broom disease (WBD) of cacao differs from other typical hemibiotrophic plant diseases by its unusually long biotrophic phase. Plant carbon sources have been proposed to regulate WBD developmental transitions; however, nothing is known about their availability at the plant-fungus interface, the apoplastic fluid of cacao. Data are provided supporting a role for the dynamics of soluble carbon in the apoplastic fluid in prompting the end of the biotrophic phase of infection. Carbon depletion and the consequent fungal sensing of starvation were identified as key signalling factors at the apoplast. MpNEP2, a fungal effector of host necrosis, was found to be up-regulated in an autophagic-like response to carbon starvation in vitro. In addition, the in vivo artificial manipulation of carbon availability in the apoplastic fluid considerably modulated both its expression and plant necrosis rate. Strikingly, infected cacao tissues accumulated intracellular hexoses, and showed stunted photosynthesis and the up-regulation of senescence markers immediately prior to the transition to the necrotrophic phase. These opposite findings of carbon depletion and accumulation in different host cell compartments are discussed within the frame of WBD development. A model is suggested to explain phase transition as a synergic outcome of fungal-related factors released upon sensing of extracellular carbon starvation, and an early senescence of infected tissues probably triggered by intracellular sugar accumulation.

  16. Apoplastic and intracellular plant sugars regulate developmental transitions in witches’ broom disease of cacao

    PubMed Central

    Barau, Joan; Grandis, Adriana; Carvalho, Vinicius Miessler de Andrade; Teixeira, Gleidson Silva; Zaparoli, Gustavo Henrique Alcalá; do Rio, Maria Carolina Scatolin; Rincones, Johana; Buckeridge, Marcos Silveira; Pereira, Gonçalo Amarante Guimarães

    2015-01-01

    Witches’ broom disease (WBD) of cacao differs from other typical hemibiotrophic plant diseases by its unusually long biotrophic phase. Plant carbon sources have been proposed to regulate WBD developmental transitions; however, nothing is known about their availability at the plant–fungus interface, the apoplastic fluid of cacao. Data are provided supporting a role for the dynamics of soluble carbon in the apoplastic fluid in prompting the end of the biotrophic phase of infection. Carbon depletion and the consequent fungal sensing of starvation were identified as key signalling factors at the apoplast. MpNEP2, a fungal effector of host necrosis, was found to be up-regulated in an autophagic-like response to carbon starvation in vitro. In addition, the in vivo artificial manipulation of carbon availability in the apoplastic fluid considerably modulated both its expression and plant necrosis rate. Strikingly, infected cacao tissues accumulated intracellular hexoses, and showed stunted photosynthesis and the up-regulation of senescence markers immediately prior to the transition to the necrotrophic phase. These opposite findings of carbon depletion and accumulation in different host cell compartments are discussed within the frame of WBD development. A model is suggested to explain phase transition as a synergic outcome of fungal-related factors released upon sensing of extracellular carbon starvation, and an early senescence of infected tissues probably triggered by intracellular sugar accumulation. PMID:25540440

  17. Unusual organization of a developmentally regulated mitochondrial RNA polymerase (TBMTRNAP) gene in Trypanosoma brucei

    PubMed Central

    Clement, Sandra L.; Koslowsky, Donna J.

    2009-01-01

    We report here the characterization of a developmentally regulated mitochondrial RNA polymerase transcript in the parasitic protozoan, Trypanosoma brucei. The 3822 bp protein-coding region of the T. brucei mitochondrial RNA polymerase (TBMTRNAP) gene is predicted to encode a 1274 amino acid polypeptide, the carboxyl-terminal domain of which exhibits 29–37% identity with the mitochondrial RNA polymerases from other organisms in the molecular databases. Interestingly, the TBMTRNAP mRNA is one of several mature mRNA species post-transcriptionally processed from a stable, polycistronic precursor. Alternative polyadenylation of the TBMTRNAP mRNA produces two mature transcripts that differ by 500 nt and that show stage-specific differences in abundance during the T. brucei life cycle. This alternative polyadenylation event appears to be accompanied by the alternative splicing of a high abundance, non-coding downstream transcript of unknown function. Our finding that the TBMTRNAP gene is transcribed into two distinct mRNAs subject to differential regulation during the T. brucei life cycle suggests that mitochondrial differentiation might be achieved in part through the regulated expression of this gene. PMID:11470527

  18. miR-14 regulates autophagy during developmental cell death by targeting ip3-kinase 2.

    PubMed

    Nelson, Charles; Ambros, Victor; Baehrecke, Eric H

    2014-11-06

    Macroautophagy (autophagy) is a lysosome-dependent degradation process that has been implicated in age-associated diseases. Autophagy is involved in both cell survival and cell death, but little is known about the mechanisms that distinguish its use during these distinct cell fates. Here, we identify the microRNA miR-14 as being both necessary and sufficient for autophagy during developmentally regulated cell death in Drosophila. Loss of miR-14 prevented induction of autophagy during salivary gland cell death, but had no effect on starvation-induced autophagy in the fat body. Moreover, misexpression of miR-14 was sufficient to prematurely induce autophagy in salivary glands, but not in the fat body. Importantly, miR-14 regulates this context-specific autophagy through its target, inositol 1,4,5-trisphosphate kinase 2 (ip3k2), thereby affecting inositol 1,4,5-trisphosphate (IP3) signaling and calcium levels during salivary gland cell death. This study provides in vivo evidence of microRNA regulation of autophagy through modulation of IP3 signaling.

  19. CRTR-1, a developmentally regulated transcriptional repressor related to the CP2 family of transcription factors.

    PubMed

    Rodda, S; Sharma, S; Scherer, M; Chapman, G; Rathjen, P

    2001-02-02

    CP2-related proteins comprise a family of DNA-binding transcription factors that are generally activators of transcription and expressed ubiquitously. We reported a differential display polymerase chain reaction fragment, Psc2, which was expressed in a regulated fashion in mouse pluripotent cells in vitro and in vivo. Here, we report further characterization of the Psc2 cDNA and function. The Psc2 cDNA contained an open reading frame homologous to CP2 family proteins. Regions implicated in DNA binding and oligomeric complex formation, but not transcription activation, were conserved. Psc2 expression in vivo during embryogenesis and in the adult mouse demonstrated tight spatial and temporal regulation, with the highest levels of expression in the epithelial lining of distal convoluted tubules in embryonic and adult kidneys. Functional analysis demonstrated that PSC2 repressed transcription 2.5-15-fold when bound to a heterologous promoter in ES, 293T, and COS-1 cells. The N-terminal 52 amino acids of PSC2 were shown to be necessary and sufficient for this activity and did not share obvious homology with reported repressor motifs. These results represent the first report of a CP2 family member that is expressed in a developmentally regulated fashion in vivo and that acts as a direct repressor of transcription. Accordingly, the protein has been named CP2-Related Transcriptional Repressor-1 (CRTR-1).

  20. Copper: a biphasic regulator of caprine sperm forward progression.

    PubMed

    Roy, Debarun; Dey, Souvik; Majumder, Gopal Chandra; Bhattacharyya, Debdas

    2014-02-01

    Copper is essential for spermatogenesis and its presence has been demonstrated in male and female reproductive fluids in several mammalian species. However, little is known about the physiological significance of this trace element in the regulation of forward progression of mammalian sperm cells which is essential for sperm fertility potential in vivo. The purpose of this investigation was to determine the physiological role of the bivalent copper ion (Cu(2+)) on mammalian sperm forward motility using a chemically-defined medium and caprine cauda epididymal sperm model. Sperm forward motility was significantly enhanced by Cu(2+) in a dose-dependent manner; maximal activation (approx 20%) was noted at the 5 µM level of the metal. Above 10 µM Cu(2+) sperm motility decreased, showing that Cu(2+) exerts a biphasic regulation on sperm motility. These findings have been confirmed using a spectrophotometric motility assay, an objective method of motility analysis. At lower concentrations (up to 5 µM), copper enhanced sperm membrane lipid peroxidation as well as the level of intra-sperm cyclic adenosine mono phosphate (c-AMP), but at a higher level it caused marked inhibition of both of the biochemical parameters. The observed correlation of Cu(2+)-dependent biphasic modulation of sperm membrane lipid peroxidation and intrasperm c-AMP with sperm forward motility is consistent with the view that Cu(2+) regulation of sperm motility is mediated by membrane lipid peroxidation, which in turn modulates the level of intra-sperm c-AMP, a well-known activator of sperm motility.

  1. The progression of severe behavior disorder in young children with intellectual and developmental disabilities.

    PubMed

    Medeiros, Kristen; Curby, Timothy W; Bernstein, Alec; Rojahn, Johannes; Schroeder, Stephen R

    2013-11-01

    Behavior disorders, such as self-injurious, stereotypic, and aggressive behavior are common among individuals with intellectual or developmental disabilities. While we have learned much about those behaviors over the past few decades, longitudinal research that looks at developmental trajectory has been rare. This study was designed to examine the trajectory of these three forms of severe behavior disorders over a one year time period. The behaviors were measured on two dimensions: frequency of occurrence and severity. Participants were 160 infants and toddlers at risk for developmental delays in Lima, Peru. Using structural equation modeling, we found that the frequency of self-injury and stereotypic behavior and the severity of aggressive behavior remained stable over the 12-month period. Uni-directional structural models fit the data best for self-injurious and aggressive behavior (with frequency being a leading indicator of future severity of self-injury and severity being a leading indicator of future frequency for aggression). For stereotypic behavior, a cross-lagged autoregressive model fit the data best, with both dimensions of frequency and severity involved as leading indicators of each other. These models did not vary significantly across diagnostic groups, suggesting that toddlers exhibiting behavior disorders may be assisted with interventions that target the specific frequencies or severities of behaviors, regardless of diagnostic category.

  2. PNUTS/PP1 Regulates RNAPII-Mediated Gene Expression and Is Necessary for Developmental Growth

    PubMed Central

    Ciurciu, Anita; Duncalf, Louise; Jonchere, Vincent; Lansdale, Nick; Vasieva, Olga; Glenday, Peter; Rudenko, Andreii; Vissi, Emese; Cobbe, Neville; Alphey, Luke; Bennett, Daimark

    2013-01-01

    In multicellular organisms, tight regulation of gene expression ensures appropriate tissue and organismal growth throughout development. Reversible phosphorylation of the RNA Polymerase II (RNAPII) C-terminal domain (CTD) is critical for the regulation of gene expression states, but how phosphorylation is actively modified in a developmental context remains poorly understood. Protein phosphatase 1 (PP1) is one of several enzymes that has been reported to dephosphorylate the RNAPII CTD. However, PP1's contribution to transcriptional regulation during animal development and the mechanisms by which its activity is targeted to RNAPII have not been fully elucidated. Here we show that the Drosophila orthologue of the PP1 Nuclear Targeting Subunit (dPNUTS) is essential for organismal development and is cell autonomously required for growth of developing tissues. The function of dPNUTS in tissue development depends on its binding to PP1, which we show is targeted by dPNUTS to RNAPII at many active sites of transcription on chromosomes. Loss of dPNUTS function or specific disruption of its ability to bind PP1 results in hyperphosphorylation of the RNAPII CTD in whole animal extracts and on chromosomes. Consistent with dPNUTS being a global transcriptional regulator, we find that loss of dPNUTS function affects the expression of the majority of genes in developing 1st instar larvae, including those that promote proliferative growth. Together, these findings shed light on the in vivo role of the PNUTS-PP1 holoenzyme and its contribution to the control of gene expression during early Drosophila development. PMID:24204300

  3. Roles of the Developmental Regulator unc-62/Homothorax in Limiting Longevity in Caenorhabditis elegans

    PubMed Central

    Van Nostrand, Eric L.; Sánchez-Blanco, Adolfo; Wu, Beijing; Nguyen, Andy; Kim, Stuart K.

    2013-01-01

    The normal aging process is associated with stereotyped changes in gene expression, but the regulators responsible for these age-dependent changes are poorly understood. Using a novel genomics approach, we identified HOX co-factor unc-62 (Homothorax) as a developmental regulator that binds proximal to age-regulated genes and modulates lifespan. Although unc-62 is expressed in diverse tissues, its functions in the intestine play a particularly important role in modulating lifespan, as intestine-specific knockdown of unc-62 by RNAi increases lifespan. An alternatively-spliced, tissue-specific isoform of unc-62 is expressed exclusively in the intestine and declines with age. Through analysis of the downstream consequences of unc-62 knockdown, we identify multiple effects linked to aging. First, unc-62 RNAi decreases the expression of yolk proteins (vitellogenins) that aggregate in the body cavity in old age. Second, unc-62 RNAi results in a broad increase in expression of intestinal genes that typically decrease expression with age, suggesting that unc-62 activity balances intestinal resource allocation between yolk protein expression and fertility on the one hand and somatic functions on the other. Finally, in old age, the intestine shows increased expression of several aberrant genes; these UNC-62 targets are expressed predominantly in neuronal cells in developing animals, but surprisingly show increased expression in the intestine of old animals. Intestinal expression of some of these genes during aging is detrimental for longevity; notably, increased expression of insulin ins-7 limits lifespan by repressing activity of insulin pathway response factor DAF-16/FOXO in aged animals. These results illustrate how unc-62 regulation of intestinal gene expression is responsible for limiting lifespan during the normal aging process. PMID:23468654

  4. An Atypical Phr Peptide Regulates the Developmental Switch Protein RapH ▿ †

    PubMed Central

    Mirouze, Nicolas; Parashar, Vijay; Baker, Melinda D.; Dubnau, David A.; Neiditch, Matthew B.

    2011-01-01

    Under conditions of nutrient limitation and high population density, the bacterium Bacillus subtilis can initiate a variety of developmental pathways. The signaling systems regulating B. subtilis differentiation are tightly controlled by switch proteins called Raps, named after the founding members of the family, which were shown to be response regulator aspartate phosphatases. A phr gene encoding a secreted pentapeptide that regulates the activity of its associated Rap protein was previously identified downstream of 8 of the chromosomally encoded rap genes. We identify and validate here the sequence of an atypical Phr peptide, PhrH, by in vivo and in vitro analyses. Using a luciferase reporter bioassay combined with in vitro experiments, we found that PhrH is a hexapeptide (TDRNTT), in contrast to the other characterized Phr pentapeptides. We also determined that phrH expression is driven by a promoter lying within rapH. Unlike the previously identified dedicated σH-driven phr promoters, it appears that phrH expression most likely requires σA. Furthermore, we show that PhrH can antagonize both of the known activities of RapH: the dephosphorylation of Spo0F and the sequestration of ComA, thus promoting the development of spores and the competent state. Finally, we propose that PhrH is the prototype of a newly identified class of Phr signaling molecules consisting of six amino acids. This class likely includes PhrI, which regulates RapI and the expression, excision, and transfer of the mobile genetic element ICEBs1. PMID:21908671

  5. Peer Relations and Emotion Regulation of Children with Emotional and Behavioural Difficulties with and without a Developmental Disorder

    ERIC Educational Resources Information Center

    Lynn, Sasha; Carroll, Annemaree; Houghton, Stephen; Cobham, Vanessa

    2013-01-01

    Children with emotional and behavioural difficulties (EBD) and those who also have developmental disorders, such as attention deficit hyperactivity disorder (ADHD) or autism spectrum disorder (ASD), can experience the same adverse consequences in their peer interactions and relationships. This present study compared the emotion regulation and peer…

  6. The Role of Intentional Self Regulation, Lower Neighborhood Ecological Assets, and Activity Involvement in Youth Developmental Outcomes

    ERIC Educational Resources Information Center

    Urban, Jennifer Brown; Lewin-Bizan, Selva; Lerner, Richard M.

    2010-01-01

    Extracurricular activities provide a key context for youth development, and participation has been linked with positive developmental outcomes. Using data from the 4-H Study of Positive Youth Development (PYD), this study explored how the intentional self regulation ability of youth interacted with participation in extracurricular activities to…

  7. The Effects of Self-Regulated Learning Training on Community College Students' Metacognition and Achievement in Developmental Math Courses

    ERIC Educational Resources Information Center

    Bol, Linda; Campbell, Karen D. Y.; Perez, Tony; Yen, Cherng-Jyh

    2016-01-01

    The effects of training in self-regulation on metacognition and math achievement were investigated. The participants were 116 community college students enrolled in developmental math courses. Students enrolled in 16 classrooms were randomly assigned to the treatment and control groups. Participants in the treatment group completed four…

  8. Using Formative Assessment and Self-Regulated Learning to Help Developmental Mathematics Students Achieve: A Multi-Campus Program

    ERIC Educational Resources Information Center

    Hudesman, John; Crosby, Sara; Ziehmke, Niesha; Everson, Howard; Issac, Sharlene; Flugman, Bert; Zimmerman, Barry; Moylan, Adam

    2014-01-01

    The authors describe an Enhanced Formative Assessment and Self-Regulated Learning (EFA-SRL) program designed to improve the achievement of community college students enrolled in developmental mathematics courses. Their model includes the use of specially formatted quizzes designed to assess both the students' mathematics and metacognitive skill…

  9. cAMP modulation during sheep in vitro oocyte maturation delays progression of meiosis without affecting oocyte parthenogenetic developmental competence.

    PubMed

    Buell, Margaret; Chitwood, James L; Ross, Pablo J

    2015-03-01

    Removal of oocytes from their natural inhibitory follicular environment results in spontaneous resumption of meiosis independent of normal signaling events that occur in vivo. Controlling the onset of meiotic resumption via maintenance of elevated oocyte cAMP levels with adenylyl cyclase (AC) activation and phosphodiesterase (PDE) inhibition, and subsequent hormone stimulation with follicle FSH has been shown to dramatically improve developmental competence of bovine and murine IVM oocytes. This study evaluated the effect of cAMP modulation during IVM of sheep oocytes on meiotic progression and development to blastocyst after parthenogenetic activation. Changes in oocyte cAMP levels were quantified during the first 2h of in vitro maturation in control or cAMP-modulating medium. No significant changes in intra-oocyte cAMP were observed under control conditions, though a slight and transient drop was noticed at 15 min of maturation. Addition of the AC stimulator Forskolin and the PDE inhibitors IBMX altered the cAMP profile, resulting in 10-fold elevation of cAMP by 15 min and sustained >3-fold elevated levels from 30 to 120 min. The effect of cAMP elevation on meiotic resumption was measured by completion of germinal vesicle breakdown. Modulated oocytes were significantly delayed when compared to control media oocytes. Also, progression to MII was significantly delayed in modulated versus control oocytes at 20 and 24h, though no differences persisted to 28 h. Lastly, when control and modulated oocytes were parthenogenetically activated, no differences in blastocyst formation were observed. Thus, while cAMP modulation delayed meiotic progression, it did not improve developmental competence of sheep IVM oocytes.

  10. Core Mechanisms Regulating Developmentally Timed and Environmentally Triggered Abscission[OPEN

    PubMed Central

    2016-01-01

    Drought-triggered abscission is a strategy used by plants to avoid the full consequences of drought; however, it is poorly understood at the molecular genetic level. Here, we show that Arabidopsis (Arabidopsis thaliana) can be used to elucidate the pathway controlling drought-triggered leaf shedding. We further show that much of the pathway regulating developmentally timed floral organ abscission is conserved in regulating drought-triggered leaf abscission. Gene expression of HAESA (HAE) and INFLORESCENCE DEFICIENT IN ABSCISSION (IDA) is induced in cauline leaf abscission zones when the leaves become wilted in response to limited water and HAE continues to accumulate in the leaf abscission zones through the abscission process. The genes that encode HAE/HAESA-LIKE2, IDA, NEVERSHED, and MAPK KINASE4 and 5 are all necessary for drought-induced leaf abscission. Our findings offer a molecular mechanism explaining drought-triggered leaf abscission. Furthermore, the ability to study leaf abscission in Arabidopsis opens up a new avenue to tease apart mechanisms involved in abscission that have been difficult to separate from flower development as well as for understanding the mechanistic role of water and turgor pressure in abscission. PMID:27468996

  11. Mechanisms regulating nutrition-dependent developmental plasticity through organ-specific effects in insects

    PubMed Central

    Koyama, Takashi; Mendes, Cláudia C.; Mirth, Christen K.

    2013-01-01

    Nutrition, via the insulin/insulin-like growth factor (IIS)/Target of Rapamycin (TOR) signaling pathway, can provide a strong molding force for determining animal size and shape. For instance, nutrition induces a disproportionate increase in the size of male horns in dung and rhinoceros beetles, or mandibles in staghorn or horned flour beetles, relative to body size. In these species, well-fed male larvae produce adults with greatly enlarged horns or mandibles, whereas males that are starved or poorly fed as larvae bear much more modest appendages. Changes in IIS/TOR signaling plays a key role in appendage development by regulating growth in the horn and mandible primordia. In contrast, changes in the IIS/TOR pathway produce minimal effects on the size of other adult structures, such as the male genitalia in fruit flies and dung beetles. The horn, mandible and genitalia illustrate that although all tissues are exposed to the same hormonal environment within the larval body, the extent to which insulin can induce growth is organ specific. In addition, the IIS/TOR pathway affects body size and shape by controlling production of metamorphic hormones important for regulating developmental timing, like the steroid molting hormone ecdysone and sesquiterpenoid hormone juvenile hormone. In this review, we discuss recent results from Drosophila and other insects that highlight mechanisms allowing tissues to differ in their sensitivity to IIS/TOR and the potential consequences of these differences on body size and shape. PMID:24133450

  12. Developmental Trajectories of Emotion Regulation Across Infancy: Do Age and the Social Partner Influence Temporal Patterns?

    PubMed

    Ekas, Naomi V; Lickenbrock, Diane M; Braungart-Rieker, Julia M

    2013-09-01

    The ability to effectively regulate emotions is a critical component of early socio-emotional development. This longitudinal study examined the developmental trajectories of emotion regulation in a sample of 3-, 5-, and 7-month-olds during an interaction with mothers and fathers. Infants' negative affect and use of behavioral strategies, including distraction, self-soothing, and high intensity motor behaviors were rated during the still-face episode of the Still-Face Paradigm. Longitudinal mixed-effects models were tested to determine whether strategies were followed by an increase or decrease in negative affect. Results from mother-infant and father-infant dyads indicated that focusing attention away from the unresponsive parent and engaging in self-soothing behaviors were associated with a subsequent decline in negative affect and the strength of these temporal associations were stable across infancy. In contrast, high-intensity motor behaviors were followed by an increase in negative affect and this effect declined over time. No significant effects were found for the behavioral strategy of looking at the parent. Results underscore the importance of considering infant age and the social partner when studying the effectiveness of emotion regulatory strategies in early infancy.

  13. On the Developmental and Environmental Regulation of Secondary Metabolism in Vaccinium spp. Berries

    PubMed Central

    Karppinen, Katja; Zoratti, Laura; Nguyenquynh, Nga; Häggman, Hely; Jaakola, Laura

    2016-01-01

    Secondary metabolites have important defense and signaling roles, and they contribute to the overall quality of developing and ripening fruits. Blueberries, bilberries, cranberries, and other Vaccinium berries are fleshy berry fruits recognized for the high levels of bioactive compounds, especially anthocyanin pigments. Besides anthocyanins and other products of the phenylpropanoid and flavonoid pathways, these berries also contain other metabolites of interest, such as carotenoid derivatives, vitamins and flavor compounds. Recently, new information has been achieved on the mechanisms related with developmental, environmental, and genetic factors involved in the regulation of secondary metabolism in Vaccinium fruits. Especially light conditions and temperature are demonstrated to have a prominent role on the composition of phenolic compounds. The present review focuses on the studies on mechanisms associated with the regulation of key secondary metabolites, mainly phenolic compounds, in Vaccinium berries. The advances in the research concerning biosynthesis of phenolic compounds in Vaccinium species, including specific studies with mutant genotypes in addition to controlled and field experiments on the genotype × environment (G×E) interaction, are discussed. The recently published Vaccinium transcriptome and genome databases provide new tools for the studies on the metabolic routes. PMID:27242856

  14. Alternatives to restrictive feeding practices to promote self-regulation in childhood: a developmental perspective.

    PubMed

    Rollins, B Y; Savage, J S; Fisher, J O; Birch, L L

    2016-10-01

    Intake of energy-dense snack foods is high among US children. Although the use of restrictive feeding practices has been shown to be counterproductive, there is very limited evidence for effective alternatives to restriction that help children moderate their intake of these foods and that facilitate the development of self-regulation in childhood. The developmental literature on parenting and child outcomes may provide insights into alternatives to restrictive feeding practices. This review paper uses a model of parental control from the child development and parenting literatures to (i) operationally define restrictive feeding practices; (ii) summarize current evidence for antecedents and effects of parental restriction use on children's eating behaviours and weight status, and (iii) highlight alternative feeding practices that may facilitate the development of children's self-regulation and moderate children's intake of palatable snack foods. We also discuss recent empirical evidence highlighting the role of child temperament and food motivation related behaviours as factors that prompt parents to use restrictive feeding practices and, yet, may increase children's dysregulated intake of forbidden foods.

  15. Developmentally Regulated Expression of the Nerve Growth Factor Receptor Gene in the Periphery and Brain

    NASA Astrophysics Data System (ADS)

    Buck, C. R.; Martinez, Humberto J.; Black, Ira B.; Chao, Moses V.

    1987-05-01

    Nerve growth factor (NGF) regulates development and maintenance of function of peripheral sympathetic and sensory neurons. A potential role for the trophic factor in brain has been detected only recently. The ability of a cell to respond to NGF is due, in part, to expression of specific receptors on the cell surface. To study tissue-specific expression of the NGF receptor gene, we have used sensitive cRNA probes for detection of NGF receptor mRNA. Our studies indicate that the receptor gene is selectively and specifically expressed in sympathetic (superior cervical) and sensory (dorsal root) ganglia in the periphery, and by the septum-basal forebrain centrally, in the neonatal rat in vivo. Moreover, examination of tissues from neonatal and adult rats reveals a marked reduction in steady-state NGF receptor mRNA levels in sensory ganglia. In contrast, a 2- to 4-fold increase was observed in the basal forebrain and in the sympathetic ganglia over the same time period. Our observations suggest that NGF receptor mRNA expression is developmentally regulated in specific areas of the nervous system in a differential fashion.

  16. Arabidopsis ribosomal proteins control vacuole trafficking and developmental programs through the regulation of lipid metabolism

    DOE PAGES

    Li, Ruixi; Sun, Ruobai; Hicks, Glenn R.; ...

    2014-12-22

    The vacuole is the most prominent compartment in plant cells and is important for ion and protein storage. In our effort to search for key regulators in the plant vacuole sorting pathway, ribosomal large subunit 4 (rpl4d) was identified as a translational mutant defective in both vacuole trafficking and normal development. Polysome profiling of the rpl4d mutant showed reduction in polysome-bound mRNA compared with wild-type, but no significant change in the general mRNA distribution pattern. Ribsomal profiling data indicated that genes in the lipid metabolism pathways were translationally down-regulated in the rpl4d mutant. Live imaging studies by Nile red stainingmore » suggested that both polar and nonpolar lipid accumulation was reduced in meristem tissues of rpl4d mutants. Pharmacological evidence showed that sterol and sphingolipid biosynthetic inhibitors can phenocopy the defects of the rpl4d mutant, including an altered vacuole trafficking pattern. Genetic evidence from lipid biosynthetic mutants indicates that alteration in the metabolism of either sterol or sphingolipid biosynthesis resulted in vacuole trafficking defects, similar to the rpl4d mutant. Tissue-specific complementation with key enzymes from lipid biosynthesis pathways can partially rescue both vacuole trafficking and auxin-related developmental defects in the rpl4d mutant. These results indicate that lipid metabolism modulates auxin-mediated tissue differentiation and endomembrane trafficking pathways downstream of ribosomal protein function.« less

  17. Developmental and stress regulation of gene expression for plastid and cytosolic isoprenoid pathways in pepper fruits.

    PubMed Central

    Hugueney, P; Bouvier, F; Badillo, A; Quennemet, J; d'Harlingue, A; Camara, B

    1996-01-01

    Plant cells synthesize a myriad of isoprenoid compounds in different subcellular compartments, which include the plastid, the mitochondria, and the endoplasmic reticulum cytosol. To start the study of the regulation of these parallel pathways, we used pepper (Capsicum annuum) fruit as a model. Using different isoprenoid biosynthetic gene probes from cloned cDNAs, we showed that only genes encoding the plastid enzymes (geranylgeranyl pyrophosphate synthase, phytoene synthase, phytoene desaturase, and capasanthin-capsorubin synthase) are specifically triggered during the normal period of development, at the ripening stage. This pattern of expression can be mimicked and precociously induced by a simple wounding stress. Concerning the cytosol-located enzymes, we observed that the expression of the gene encoding farnesyl pyrophosphate synthase is constitutive, whereas that of farnesyl pyrophosphate cyclase (5-epi-aristolochene synthase) is undetectable during the normal development of the fruit. The expression of these later genes are, however, only selectively triggered after elicitor treatment. The results provide evidence for developmental control of isoprenoid biosynthesis occurring in plastids and that cytoplasmic isoprenoid biosynthesis is regulated, in part, by environmental signals. PMID:8787029

  18. Identification of a developmentally regulated iron superoxide dismutase of Trypanosoma brucei.

    PubMed Central

    Kabiri, M; Steverding, D

    2001-01-01

    An iron superoxide dismutase (FeSOD) gene of the protozoan parasite Trypanosoma brucei has been cloned and its gene product functionally characterized. The gene encodes a protein of 198 residues which shows 80% identity with FeSODs from other trypanosomatids. Inhibitor studies with purified recombinant FeSOD expressed in Escherichia coli confirmed that the enzyme is an iron-containing SOD. The FeSOD is developmentally regulated in the parasite, expression being lowest in the cell-cycle-arrested, short stumpy bloodstream forms. Differential expression of the FeSOD protein contrasts with only minor quantitative changes in the FeSOD mRNA, indicating post-transcriptional regulation of the enzyme. As the level of FeSOD increases during differentiation of cell-cycle-arrested short stumpy into dividing procyclic forms, it is suggested that the enzyme is only required in proliferating stages of the parasite for the elimination of superoxide radicals which are released during the generation of the iron-tyrosyl free-radical centre in the small subunit of ribonucleotide reductase. PMID:11696005

  19. Developmental and environmental regulation of antifreeze proteins in the mealworm beetle Tenebrio molitor.

    PubMed

    Graham, L A; Walker, V K; Davies, P L

    2000-11-01

    The yellow mealworm beetle, Tenebrio molitor, contains a family of small Cys-rich and Thr-rich thermal hysteresis proteins that depress the hemolymph freezing point below the melting point by as much as 5. 5 degrees C (DeltaT = thermal hysteresis). Thermal hysteresis protein expression was evaluated throughout development and after exposure to altered environmental conditions. Under favorable growth conditions, small larvae (11-13 mg) had only low levels of thermal hysteresis proteins or thermal hysteresis protein message, but these levels increased 10-fold and 18-fold, respectively, by the final larval instar (> 190 mg), resulting in thermal hysteresis > 3 degrees C. Exposure of small larvae (11-13 mg) to 4 weeks of cold (4 degrees C) caused an approximately 20-fold increase in thermal hysteresis protein concentration, well in excess of the less than threefold developmental increase seen after 4 weeks at 22 degrees C. Exposure of large larvae (100-120 mg) to cold caused 12-fold and sixfold increases in thermal hysteresis protein message and protein levels, respectively, approximately double the maximum levels they would have attained in the final larval instar at 22 degrees C. Thus, thermal hysteresis increased to similar levels (> 4 degrees C) in the cold, irrespective of the size of the larvae (the overwintering stage). At pupation, thermal hysteresis protein message levels decreased > 20-fold and remained low thereafter, but thermal hysteresis activity decreased much more slowly. Exposure to cold did not reverse this decline. Desiccation or starvation of larvae had comparable effects to cold exposure, but surprisingly, short daylength photoperiod or total darkness had no effect on either thermal hysteresis or message levels. As all environmental conditions that caused increased thermal hysteresis also inhibited growth, we postulate that developmental arrest is a primary factor in the regulation of T. molitor thermal hysteresis proteins.

  20. Developmental strategies and regulation of cell-free enzyme system for ethanol production: a molecular prospective.

    PubMed

    Khattak, Waleed Ahmad; Ullah, Muhammad Wajid; Ul-Islam, Mazhar; Khan, Shaukat; Kim, Minah; Kim, Yeji; Park, Joong Kon

    2014-12-01

    Most biomanufacturing systems developed for the production of biocommodities are based on whole-cell systems. However, with the advent of innovative technologies, the focus has shifted from whole-cell towards cell-free enzyme system. Since more than a century, researchers are using the cell-free extract containing the required enzymes and their respective cofactors in order to study the fundamental aspects of biological systems, particularly fermentation. Although yeast cell-free enzyme system is known since long ago, it is rarely been studied and characterized in detail. In this review, we hope to describe the major pitfalls encountered by whole-cell system and introduce possible solutions to them using cell-free enzyme systems. We have discussed the glycolytic and fermentative pathways and their regulation at both transcription and translational levels. Moreover, several strategies employed for development of cell-free enzyme system have been described with their potential merits and shortcomings associated with these developmental approaches. We also described in detail the various developmental approaches of synthetic cell-free enzyme system such as compartmentalization, metabolic channeling, protein fusion, and co-immobilization strategies. Additionally, we portrayed the novel cell-free enzyme technologies based on encapsulation and immobilization techniques and their development and commercialization. Through this review, we have presented the basics of cell-free enzyme system, the strategies involved in development and operation, and the advantages over conventional processes. Finally, we have addressed some potential directions for the future development and industrialization of cell-free enzyme system.

  1. Myosin Va is developmentally regulated and expressed in the human cerebellum from birth to old age

    PubMed Central

    Souza, C.C.R.; Dombroski, T.C.D.; Machado, H.R.; Oliveira, R.S.; Rocha, L.B.; Rodrigues, A.R.A.; Neder, L.; Chimelli, L.; Corrêa, V.M.A.; Larson, R.E.; Martins, A.R.

    2013-01-01

    Myosin Va functions as a processive, actin-based motor molecule highly enriched in the nervous system, which transports and/or tethers organelles, vesicles, and mRNA and protein translation machinery. Mutation of myosin Va leads to Griscelli disease that is associated with severe neurological deficits and a short life span. Despite playing a critical role in development, the expression of myosin Va in the central nervous system throughout the human life span has not been reported. To address this issue, the cerebellar expression of myosin Va from newborns to elderly humans was studied by immunohistochemistry using an affinity-purified anti-myosin Va antibody. Myosin Va was expressed at all ages from the 10th postnatal day to the 98th year of life, in molecular, Purkinje and granular cerebellar layers. Cerebellar myosin Va expression did not differ essentially in localization or intensity from childhood to old age, except during the postnatal developmental period. Structures resembling granules and climbing fibers in Purkinje cells were deeply stained. In dentate neurons, long processes were deeply stained by anti-myosin Va, as were punctate nuclear structures. During the first postnatal year, myosin Va was differentially expressed in the external granular layer (EGL). In the EGL, proliferating prospective granule cells were not stained by anti-myosin Va antibody. In contrast, premigratory granule cells in the EGL stained moderately. Granule cells exhibiting a migratory profile in the molecular layer were also moderately stained. In conclusion, neuronal myosin Va is developmentally regulated, and appears to be required for cerebellar function from early postnatal life to senescence. PMID:23558932

  2. ELF5-Mediated AR Activation Regulates Prostate Cancer Progression

    PubMed Central

    Li, Kai; Guo, Yongmin; Yang, Xiong; Zhang, Zhihong; Zhang, Changwen; Xu, Yong

    2017-01-01

    The transcription factor E74-like factor 5 (ELF5) is a potent antioncogene that can prevent epithelial-mesenchymal transition (EMT) and metastasis in prostate cancer (PCa). However, little is known how it suppress the tumor growth and if it can interact with androgen receptor (AR). In this study, we find that the ELF5 is frequently expressed in AR activated PCa cells, where it binds to AR acting as a physiological partner and negatively regulates its transcriptional activity. In addition, the interaction between ELF5 and AR is androgen-dependent. Downregulation of ELF5 by shRNA increases the expression of AR-response genes and the progression of PCa. Moreover, ELF5 is a AR-dependent gene that its expression can be induced by androgen and suppressed by antiandrogen treatment. Notably, forced reduction of ELF5 in LNCaP cells facilitates the binding of AR to ARE in ELF5 gene and enabling its transcription, so that low level ELF5 can turn up its own expression by the negative feedback loop. PMID:28287091

  3. ELF5-Mediated AR Activation Regulates Prostate Cancer Progression.

    PubMed

    Li, Kai; Guo, Yongmin; Yang, Xiong; Zhang, Zhihong; Zhang, Changwen; Xu, Yong

    2017-03-13

    The transcription factor E74-like factor 5 (ELF5) is a potent antioncogene that can prevent epithelial-mesenchymal transition (EMT) and metastasis in prostate cancer (PCa). However, little is known how it suppress the tumor growth and if it can interact with androgen receptor (AR). In this study, we find that the ELF5 is frequently expressed in AR activated PCa cells, where it binds to AR acting as a physiological partner and negatively regulates its transcriptional activity. In addition, the interaction between ELF5 and AR is androgen-dependent. Downregulation of ELF5 by shRNA increases the expression of AR-response genes and the progression of PCa. Moreover, ELF5 is a AR-dependent gene that its expression can be induced by androgen and suppressed by antiandrogen treatment. Notably, forced reduction of ELF5 in LNCaP cells facilitates the binding of AR to ARE in ELF5 gene and enabling its transcription, so that low level ELF5 can turn up its own expression by the negative feedback loop.

  4. Developmental changes in Ca2+ channel subtypes regulating endocytosis at the calyx of Held.

    PubMed

    Midorikawa, Mitsuharu; Okamoto, Yuji; Sakaba, Takeshi

    2014-08-15

    At the mammalian central synapse, Ca(2+) influx through Ca(2+) channels triggers neurotransmitter release by exocytosis of synaptic vesicles, which fuse with the presynaptic membrane and are subsequently retrieved by endocytosis. At the calyx of Held terminal, P/Q-type Ca(2+) channels mainly mediate exocytosis, while N- and R-type channels have a minor role in young terminals (postnatal days 8-11). The role of each Ca(2+) channel subtype in endocytosis remains to be elucidated; therefore, we examined the role of each type of Ca(2+) channel in endocytosis, by using whole-cell patch-clamp recordings in conjunction with capacitance measurement techniques. We found that at the young calyx terminal, when R-type Ca(2+) channels were blocked, the slow mode of endocytosis was further slowed, while blocking of either P/Q- or N-type Ca(2+) channels had no major effect. In more mature terminals (postnatal days 14-17), the slow mode of endocytosis was mainly triggered by P/Q-type Ca(2+) channels, suggesting developmental changes in the regulation of the slow mode of endocytosis by different Ca(2+) channel subtypes. In contrast, a fast mode of endocytosis was observed after strong stimulation in young terminals that was mediated mainly by P/Q-type, but not R- or N-type Ca(2+) channels. These results suggest that different types of Ca(2+) channels regulate the two different modes of endocytosis. The results may also suggest that exo- and endocytosis are regulated independently at different sites in young animals but are more tightly coupled in older animals, allowing more efficient synaptic vesicle cycling adapted for fast signalling.

  5. Developmental regulation of voltage-sensitive sodium channels in rat skeletal muscle

    SciTech Connect

    Sherman, S.J.

    1985-01-01

    The developmental regulation of the voltage-sensitive Na/sup +/ channel in rat skeletal muscle was studied in vivo and in vitro. In triceps surae muscle developing in vivo the development of TTX-sensitive Na/sup +/ channel occurred primarily during the first three postnatal weeks as determined by the specific binding of (/sup 3/H)saxitoxin. This development proceeded in two separate phases. The first phase occurs independently of continuing motor neuron innervation and accounts for 60% of the adult density of TTX-sensitive Na/sup +/ channels. The second phase, which begins about day 11, requires innervation. Muscle cells in primary culture were found to have both TTX-sensitive and insensitive Na/sup +/ channels. The development of the TTX-sensitive channel, in vitro, paralleled the initial innervation-independent phase of development observed in vivo. The density of TTX-sensitive Na/sup +/ channels in cultured muscle cells was regulated by electrical activity and cytosolic Ca/sup + +/ levels. Pharmacological blockade of the spontaneous electrical activity present in these cells lead to a nearly 2-fold increase in the surface density of TTX-sensitive channels. The turnover time of the TTX-sensitive Na/sup +/ channel was measured by blocking the incorporation of newly synthesized channels with tunicamycin, an inhibitor of N-linked protein glycosylation. The regulation of channel density by electrical activity, cytosolic Ca/sup + +/levels, and agents affecting cyclic neucleotide levels had no effect on the turnover time of the TTX-sensitive Na/sup +/ channel, indicating that these regulatory agents instead affect the synthesis of the channel.

  6. Developmental changes in Ca2+ channel subtypes regulating endocytosis at the calyx of Held

    PubMed Central

    Midorikawa, Mitsuharu; Okamoto, Yuji; Sakaba, Takeshi

    2014-01-01

    At the mammalian central synapse, Ca2+ influx through Ca2+ channels triggers neurotransmitter release by exocytosis of synaptic vesicles, which fuse with the presynaptic membrane and are subsequently retrieved by endocytosis. At the calyx of Held terminal, P/Q-type Ca2+ channels mainly mediate exocytosis, while N- and R-type channels have a minor role in young terminals (postnatal days 8–11). The role of each Ca2+ channel subtype in endocytosis remains to be elucidated; therefore, we examined the role of each type of Ca2+ channel in endocytosis, by using whole-cell patch-clamp recordings in conjunction with capacitance measurement techniques. We found that at the young calyx terminal, when R-type Ca2+ channels were blocked, the slow mode of endocytosis was further slowed, while blocking of either P/Q- or N-type Ca2+ channels had no major effect. In more mature terminals (postnatal days 14–17), the slow mode of endocytosis was mainly triggered by P/Q-type Ca2+ channels, suggesting developmental changes in the regulation of the slow mode of endocytosis by different Ca2+ channel subtypes. In contrast, a fast mode of endocytosis was observed after strong stimulation in young terminals that was mediated mainly by P/Q-type, but not R- or N-type Ca2+ channels. These results suggest that different types of Ca2+ channels regulate the two different modes of endocytosis. The results may also suggest that exo- and endocytosis are regulated independently at different sites in young animals but are more tightly coupled in older animals, allowing more efficient synaptic vesicle cycling adapted for fast signalling. PMID:24907302

  7. Developmental Regulation of Genes Encoding Universal Stress Proteins in Schistosoma mansoni

    PubMed Central

    Isokpehi, Raphael D.; Mahmud, Ousman; Mbah, Andreas N.; Simmons, Shaneka S.; Avelar, Lívia; Rajnarayanan, Rajendram V.; Udensi, Udensi K.; Ayensu, Wellington K.; Cohly, Hari H.; Brown, Shyretha D.; Dates, Centdrika R.; Hentz, Sonya D.; Hughes, Shawntae J.; Smith-McInnis, Dominique R.; Patterson, Carvey O.; Sims, Jennifer N.; Turner, Kelisha T.; Williams, Baraka S.; Johnson, Matilda O.; Adubi, Taiwo; Mbuh, Judith V.; Anumudu, Chiaka I.; Adeoye, Grace O.; Thomas, Bolaji N.; Nashiru, Oyekanmi; Oliveira, Guilherme

    2011-01-01

    The draft nuclear genome sequence of the snail-transmitted, dimorphic, parasitic, platyhelminth Schistosoma mansoni revealed eight genes encoding proteins that contain the Universal Stress Protein (USP) domain. Schistosoma mansoni is a causative agent of human schistosomiasis, a severe and debilitating Neglected Tropical Disease (NTD) of poverty, which is endemic in at least 76 countries. The availability of the genome sequences of Schistosoma species presents opportunities for bioinformatics and genomics analyses of associated gene families that could be targets for understanding schistosomiasis ecology, intervention, prevention and control. Proteins with the USP domain are known to provide bacteria, archaea, fungi, protists and plants with the ability to respond to diverse environmental stresses. In this research investigation, the functional annotations of the USP genes and predicted nucleotide and protein sequences were initially verified. Subsequently, sequence clusters and distinctive features of the sequences were determined. A total of twelve ligand binding sites were predicted based on alignment to the ATP-binding universal stress protein from Methanocaldococcus jannaschii. In addition, six USP sequences showed the presence of ATP-binding motif residues indicating that they may be regulated by ATP. Public domain gene expression data and RT-PCR assays confirmed that all the S. mansoni USP genes were transcribed in at least one of the developmental life cycle stages of the helminth. Six of these genes were up-regulated in the miracidium, a free-swimming stage that is critical for transmission to the snail intermediate host. It is possible that during the intra-snail stages, S. mansoni gene transcripts for universal stress proteins are low abundant and are induced to perform specialized functions triggered by environmental stressors such as oxidative stress due to hydrogen peroxide that is present in the snail hemocytes. This report serves to catalyze the

  8. Reciprocity in the developmental regulation of aquaporins 1, 3 and 5 during pregnancy and lactation in the rat.

    PubMed

    Nazemi, Sasan; Rahbek, Mette; Parhamifar, Ladan; Moghimi, Seyed Moein; Babamoradi, Hamid; Mehrdana, Foojan; Klærke, Dan Arne; Knight, Christopher H

    2014-01-01

    Milk secretion involves significant flux of water, driven largely by synthesis of lactose within the Golgi apparatus. It has not been determined whether this flux is simply a passive consequence of the osmotic potential between cytosol and Golgi, or whether it involves regulated flow. Aquaporins (AQPs) are membrane water channels that regulate water flux. AQP1, AQP3 and AQP5 have previously been detected in mammary tissue, but evidence of developmental regulation (altered expression according to the developmental and physiological state of the mammary gland) is lacking and their cellular/subcellular location is not well understood. In this paper we present evidence of developmental regulation of all three of these AQPs. Further, there was evidence of reciprocity since expression of the rather abundant AQP3 and less abundant AQP1 increased significantly from pregnancy into lactation, whereas expression of the least abundant AQP5 decreased. It would be tempting to suggest that AQP3 and AQP1 are involved in the secretion of water into milk. Paradoxically, however, it was AQP5 that demonstrated most evidence of expression located at the apical (secretory) membrane. The possibility is discussed that AQP5 is synthesized during pregnancy as a stable protein that functions to regulate water secretion during lactation. AQP3 was identified primarily at the basal and lateral membranes of the secretory cells, suggesting a possible involvement in regulated uptake of water and glycerol. AQP1 was identified primarily at the capillary and secretory cell cytoplasmic level and may again be more concerned with uptake and hence milk synthesis, rather than secretion. The fact that expression was developmentally regulated supports, but does not prove, a regulatory involvement of AQPs in water flux through the milk secretory cell.

  9. Mutations in mitochondrial enzyme GPT2 cause metabolic dysfunction and neurological disease with developmental and progressive features

    PubMed Central

    Ouyang, Qing; Nakayama, Tojo; Baytas, Ozan; Davidson, Shawn M.; Yang, Chendong; Schmidt, Michael; Lizarraga, Sofia B.; Mishra, Sasmita; EI-Quessny, Malak; Niaz, Saima; Gul Butt, Mirrat; Imran Murtaza, Syed; Javed, Afzal; Chaudhry, Haroon Rashid; Vaughan, Dylan J.; Hill, R. Sean; Partlow, Jennifer N.; Yoo, Seung-Yun; Lam, Anh-Thu N.; Nasir, Ramzi; Al-Saffar, Muna; Barkovich, A. James; Schwede, Matthew; Nagpal, Shailender; Rajab, Anna; DeBerardinis, Ralph J.; Housman, David E.; Mochida, Ganeshwaran H.; Morrow, Eric M.

    2016-01-01

    Mutations that cause neurological phenotypes are highly informative with regard to mechanisms governing human brain function and disease. We report autosomal recessive mutations in the enzyme glutamate pyruvate transaminase 2 (GPT2) in large kindreds initially ascertained for intellectual and developmental disability (IDD). GPT2 [also known as alanine transaminase 2 (ALT2)] is one of two related transaminases that catalyze the reversible addition of an amino group from glutamate to pyruvate, yielding alanine and α-ketoglutarate. In addition to IDD, all affected individuals show postnatal microcephaly and ∼80% of those followed over time show progressive motor symptoms, a spastic paraplegia. Homozygous nonsense p.Arg404* and missense p.Pro272Leu mutations are shown biochemically to be loss of function. The GPT2 gene demonstrates increasing expression in brain in the early postnatal period, and GPT2 protein localizes to mitochondria. Akin to the human phenotype, Gpt2-null mice exhibit reduced brain growth. Through metabolomics and direct isotope tracing experiments, we find a number of metabolic abnormalities associated with loss of Gpt2. These include defects in amino acid metabolism such as low alanine levels and elevated essential amino acids. Also, we find defects in anaplerosis, the metabolic process involved in replenishing TCA cycle intermediates. Finally, mutant brains demonstrate misregulated metabolites in pathways implicated in neuroprotective mechanisms previously associated with neurodegenerative disorders. Overall, our data reveal an important role for the GPT2 enzyme in mitochondrial metabolism with relevance to developmental as well as potentially to neurodegenerative mechanisms. PMID:27601654

  10. Developmental expression and regulation of flavin-containing monooxygenase by the unfolded protein response in Japanese medaka (Oryzias latipes).

    PubMed

    Kupsco, Allison; Schlenk, Daniel

    2017-01-01

    Flavin-containing monooxygenases (FMOs) play a key role in xenobiotic metabolism, are regulated by environmental conditions, and are differentially regulated during mammalian development. Japanese medaka (Oryzias latipes) are a common model organism for toxicological studies. The goal of the current research was to characterize developmental expression and regulation of FMOs in Japanese medaka embryos to better understand the role of FMOs in this model species. Five putative medaka fmos were characterized from the medaka genome through the National Center for Biotechnology Information (NCBI) database by protein motifs and alignments, then identified as fmo4, fmo5A, fmo5B, fmo5C and fmo5D for the current study. Fmo gene expression was analyzed at 1dpf, 3dpf, 6dpf and 9dpf and distinct developmental patterns of expression were observed. Fmo4 and fmo5D increased 3-fold during mid organogenesis (6dpf), while fmo5B and fmo5C decreased significantly in early organogenesis (3dpf) and fmo5A was unaltered. Promoter analysis was performed for transcription factor binding sites and indicated regulation by developmental factors and a role for the unfolded protein response in fmo modulation. Fmo regulation by the UPR was assessed with treatments of 1μg/ml, 2μg/ml, and 4μg/ml Tunicamycin (Tm), and 2mM and 4mM dithiothreitol (DTT), well-known inducers of endoplasmic reticulum stress, for 24h from 5-6dpf. High concentrations to Tm induced fmo4 and fmo5A up to two-fold, while DTT significantly decreased expression of fmo5A, fmo5B, and fmo5C. Results suggest that medaka fmos are variably regulated by the UPR during organogenesis with variable developmental expression, and suggesting potential stage-dependent activation or detoxification of xenobiotics.

  11. Developmentally Regulated SCN5A Splice Variant Potentiates Dysfunction of a Novel Mutation Associated with Severe Fetal Arrhythmia

    PubMed Central

    Murphy, Lisa L.; Moon-Grady, Anita J.; Cuneo, Bettina F.; Wakai, Ronald T.; Yu, Suhong; Kunic, Jennifer D.; Benson, D. Woodrow; George, Alfred L.

    2011-01-01

    Background Congenital long-QT syndrome (LQTS) may present during fetal development and can be life-threatening. The molecular mechanism for the unusual early onset of LQTS during fetal development is unknown. Objective We sought to elucidate the molecular basis for severe fetal LQTS presenting at 19-weeks gestation, the earliest known presentation of this disease. Methods Fetal magnetocardiography was used to demonstrated torsade de pointes and a prolonged rate-corrected QT interval. In vitro electrophysiological studies were performed to determine functional consequences of a novel SCN5A mutation found in the fetus. Results The fetus presented with episodes of ventricular ectopy progressing to incessant ventricular tachycardia and hydrops fetalis. Genetic analysis disclosed a novel, de novo heterozygous mutation in SCN5A (L409P) and a homozygous common variant (R558). In vitro electrophysiological studies demonstrated that the mutation in combination with R558 caused significant depolarized shifts in voltage-dependence of inactivation and activation, faster recovery from inactivation and a 7-fold greater level of persistent current. When the mutation was engineered in a fetal-expressed SCN5A splice isoform, channel dysfunction was markedly potentiated. Also, R558 alone in the fetal splice isoform evoked a large persistent current, hence both alleles were dysfunctional. Conclusion We report the earliest confirmed diagnosis of symptomatic LQTS, and present evidence that mutant cardiac sodium channel dysfunction is potentiated by a developmentally regulated alternative splicing event in SCN5A. Our findings provide a plausible mechanism for the unusual severity and early onset of cardiac arrhythmia in fetal LQTS. PMID:22064211

  12. Developmental regulation of G protein-gated inwardly-rectifying K+ (GIRK/KIR3) channel subunits in the brain

    PubMed Central

    Fernández-Alacid, Laura; Watanabe, Masahiko; Molnár, Elek; Wickman, Kevin; Luján, Rafael

    2013-01-01

    G protein-gated inwardly-rectifying K+ (GIRK/family 3 of inwardly-rectifying K+) channels are coupled to neurotransmitter action and can play important roles in modulating neuronal excitability. We investigated the temporal and spatial expression of GIRK1, GIRK2 and GIRK3 subunits in the developing and adult rodent brain using biochemical, immunohistochemical and immunoelectron microscopic techniques. At all ages analysed, the overall distribution patterns of GIRK1-3 were very similar, with high expression levels in the neocortex, cerebellum, hippocampus and thalamus. Focusing on the hippocampus, histoblotting and immunohistochemistry showed that GIRK1-3 protein levels increased with age, and this was accompanied by a shift in the subcellular localization of the subunits. Early in development (postnatal day 5), GIRK subunits were predominantly localized to the endoplasmic reticulum in the pyramidal cells, but by postnatal day 60 they were mostly found along the plasma membrane. During development, GIRK1 and GIRK2 were found primarily at postsynaptic sites, whereas GIRK3 was predominantly detected at presynaptic sites. In addition, GIRK1 and GIRK2 expression on the spine plasma membrane showed identical proximal-to-distal gradients that differed from GIRK3 distribution. Furthermore, although GIRK1 was never found within the postsynaptic density (PSD), the level of GIRK2 in the PSD progressively increased and GIRK3 did not change in the PSD during development. Together, these findings shed new light on the developmental regulation and subcellular diversity of neuronal GIRK channels, and support the contention that distinct subpopulations of GIRK channels exert separable influences on neuronal excitability. The ability to selectively target specific subpopulations of GIRK channels may prove effective in the treatment of disorders of excitability. PMID:22098295

  13. The developmental and environmental regulation of gravitropic setpoint angle in Arabidopsis and bean

    PubMed Central

    Roychoudhry, Suruchi; Kieffer, Martin; Del Bianco, Marta; Liao, Che-Yang; Weijers, Dolf; Kepinski, Stefan

    2017-01-01

    Root and shoot branches are major determinants of plant form and critical for the effective capture of resources below and above ground. These branches are often maintained at specific angles with respect to gravity, known as gravitropic set point angles (GSAs). We have previously shown that the mechanism permitting the maintenance of non-vertical GSAs is highly auxin-dependent and here we investigate the developmental and environmental regulation of root and shoot branch GSA. We show that nitrogen and phosphorous deficiency have opposing, auxin signalling-dependent effects on lateral root GSA in Arabidopsis: while low nitrate induces less vertical lateral root GSA, phosphate deficiency results in a more vertical lateral root growth angle, a finding that contrasts with the previously reported growth angle response of bean adventitious roots. We find that this root-class-specific discrepancy in GSA response to low phosphorus is mirrored by similar differences in growth angle response to auxin treatment between these root types. Finally we show that both shaded, low red/far-red light conditions and high temperature induce more vertical growth in Arabidopsis shoot branches. We discuss the significance of these findings in the context of efforts to improve crop performance via the manipulation of root and shoot branch growth angle. PMID:28256503

  14. Clique of functional hubs orchestrates population bursts in developmentally regulated neural networks

    NASA Astrophysics Data System (ADS)

    Torcini, Alessandro; Luccioli, Stefano; Bonifazi, Paolo; Ben-Jacob, Eshel; Barzilai, Ari

    2015-03-01

    It has recently been discovered that single neuron stimulation can impact network dynamics in immature and adult neuronal circuits. Here we report a novel mechanism which can explain in developing neuronal circuits, typically composed of only excitatory cells, the peculiar role played by a few specific neurons in promoting/arresting the population activity. For this purpose, we consider a standard neuronal network model, with short-term synaptic plasticity, whose population activity is characterized by bursting behavior. The addition of developmentally regulated constraints on single neuron excitability and connectivity leads to the emergence of functional hub neurons, whose stimulation/deletion is critical for the network activity. Functional hubs form a clique, where a precise sequential activation of the neurons is essential to ignite collective events without any need for a specific topological architecture. Unsupervised time-lagged firings of supra-threshold cells, in connection with coordinated entrainments of near-threshold neurons, are the key ingredients to orchestrate population activity. This work is part of the activity of the Joint Italian-Israeli Laboratory on Integrative Network Neuroscience supported by the Italian Ministry of Foreign Affairs.

  15. Developmental profiling of postnatal dentate gyrus progenitors provides evidence for dynamic cell-autonomous regulation

    PubMed Central

    Gilley, Jennifer A.; Yang, Cui-Ping; Kernie, Steven G.

    2009-01-01

    The dentate gyrus of the hippocampus is one of the most prominent regions in the postnatal mammalian brain where neurogenesis continues throughout life. There is tremendous speculation regarding the potential implications of adult hippocampal neurogenesis, though it remains unclear to what extent this ability becomes attenuated during normal aging, and what genetic changes in the progenitor population ensue over time. Using defined elements of the nestin promoter, we developed a transgenic mouse that reliably labels neural stem and early progenitors with green fluorescent protein (GFP). Using a combination of immunohistochemical and flow cytometry techniques, we characterized the progenitor cells within the dentate gyrus and created a developmental profile from postnatal day 7 (P7) until 6 months of age. In addition, we demonstrate that the proliferative potential of these progenitors is controlled at least in part by cell-autonomous cues. Finally, in order to identify what may underlie these differences, we performed stem cell-specific microarrays on GFP-expressing sorted cells from isolated P7 and postnatal day 28 (P28) dentate gyrus. We identified several differentially expressed genes that may underlie the functional differences that we observe in neurosphere assays from sorted cells and differentiation assays at these different ages. These data suggest that neural progenitors from the dentate gyrus are differentially regulated by cell-autonomous factors that change over time. PMID:20014381

  16. Developmental Wiring of Specific Neurons Is Regulated by RET-1/Nogo-A in Caenorhabditis elegans

    PubMed Central

    Torpe, Nanna; Nørgaard, Steffen; Høye, Anette M.; Pocock, Roger

    2017-01-01

    Nogo-A is a membrane-bound protein that functions to inhibit neuronal migration, adhesion, and neurite outgrowth during development. In the mature nervous system, Nogo-A stabilizes neuronal wiring to inhibit neuronal plasticity and regeneration after injury. Here, we show that RET-1, the sole Nogo-A homolog in Caenorhabditis elegans, is required to control developmental wiring of a specific subset of neurons. In ret-1 deletion mutant animals, specific ventral nerve cord axons are misguided where they fail to respect the ventral midline boundary. We found that ret-1 is expressed in multiple neurons during development, and, through mosaic analysis, showed that ret-1 controls axon guidance in a cell-autonomous manner. Finally, as in mammals, ret-1 regulates ephrin expression, and dysregulation of the ephrin ligand VAB-2 is partially responsible for the ret-1 mutant axonal defects. Together, our data present a previously unidentified function for RET-1 in the nervous system of C. elegans. PMID:27821431

  17. Sequential evolution of bacterial morphology by co-option of a developmental regulator.

    PubMed

    Jiang, Chao; Brown, Pamela J B; Ducret, Adrien; Brun, Yves V

    2014-02-27

    What mechanisms underlie the transitions responsible for the diverse shapes observed in the living world? Although bacteria exhibit a myriad of morphologies, the mechanisms responsible for the evolution of bacterial cell shape are not understood. We investigated morphological diversity in a group of bacteria that synthesize an appendage-like extension of the cell envelope called the stalk. The location and number of stalks varies among species, as exemplified by three distinct subcellular positions of stalks within a rod-shaped cell body: polar in the genus Caulobacter and subpolar or bilateral in the genus Asticcacaulis. Here we show that a developmental regulator of Caulobacter crescentus, SpmX, is co-opted in the genus Asticcacaulis to specify stalk synthesis either at the subpolar or bilateral positions. We also show that stepwise evolution of a specific region of SpmX led to the gain of a new function and localization of this protein, which drove the sequential transition in stalk positioning. Our results indicate that changes in protein function, co-option and modularity are key elements in the evolution of bacterial morphology. Therefore, similar evolutionary principles of morphological transitions apply to both single-celled prokaryotes and multicellular eukaryotes.

  18. Sequential evolution of bacterial morphology by co-option of a developmental regulator

    NASA Astrophysics Data System (ADS)

    Jiang, Chao; Brown, Pamela J. B.; Ducret, Adrien; Brun, Yves V.

    2014-02-01

    What mechanisms underlie the transitions responsible for the diverse shapes observed in the living world? Although bacteria exhibit a myriad of morphologies, the mechanisms responsible for the evolution of bacterial cell shape are not understood. We investigated morphological diversity in a group of bacteria that synthesize an appendage-like extension of the cell envelope called the stalk. The location and number of stalks varies among species, as exemplified by three distinct subcellular positions of stalks within a rod-shaped cell body: polar in the genus Caulobacter and subpolar or bilateral in the genus Asticcacaulis. Here we show that a developmental regulator of Caulobacter crescentus, SpmX, is co-opted in the genus Asticcacaulis to specify stalk synthesis either at the subpolar or bilateral positions. We also show that stepwise evolution of a specific region of SpmX led to the gain of a new function and localization of this protein, which drove the sequential transition in stalk positioning. Our results indicate that changes in protein function, co-option and modularity are key elements in the evolution of bacterial morphology. Therefore, similar evolutionary principles of morphological transitions apply to both single-celled prokaryotes and multicellular eukaryotes.

  19. Sequential evolution of bacterial morphology by co-option of a developmental regulator

    PubMed Central

    Jiang, Chao; Brown, Pamela J.B.; Ducret, Adrien; Brun1, Yves V.

    2014-01-01

    What mechanisms underlie the transitions responsible for the diverse shapes observed in the living world? While bacteria display a myriad of morphologies1, the mechanisms responsible for the evolution of bacterial cell shape are not understood. We investigated morphological diversity in a group of bacteria that synthesize an appendage-like extension of the cell envelope called the stalk2,3. The location and number of stalks varies among species, as exemplified by three distinct sub-cellular positions of stalks within a rod-shaped cell body: polar in the Caulobacter genus, and sub-polar or bi-lateral in the Asticcacaulis genus4. Here we show that a developmental regulator of Caulobacter crescentus, SpmX5, was co-opted in the Asticcacaulis genus to specify stalk synthesis at either the sub-polar or bi-lateral positions. We show that stepwise evolution of a specific region of SpmX led to the gain of a new function and localization of this protein, which drove the sequential transition in stalk positioning. Our results indicate that evolution of protein function, co-option, and modularity are key elements in the evolution of bacterial morphology. Therefore, similar evolutionary principles of morphological transitions apply to both single-celled prokaryotes and multicellular eukaryotes. PMID:24463524

  20. MicroRNA-101 Regulates Multiple Developmental Programs to Constrain Excitation in Adult Neural Networks.

    PubMed

    Lippi, Giordano; Fernandes, Catarina C; Ewell, Laura A; John, Danielle; Romoli, Benedetto; Curia, Giulia; Taylor, Seth R; Frady, E Paxon; Jensen, Anne B; Liu, Jerry C; Chaabane, Melanie M; Belal, Cherine; Nathanson, Jason L; Zoli, Michele; Leutgeb, Jill K; Biagini, Giuseppe; Yeo, Gene W; Berg, Darwin K

    2016-12-21

    A critical feature of neural networks is that they balance excitation and inhibition to prevent pathological dysfunction. How this is achieved is largely unknown, although deficits in the balance contribute to many neurological disorders. We show here that a microRNA (miR-101) is a key orchestrator of this essential feature, shaping the developing network to constrain excitation in the adult. Transient early blockade of miR-101 induces long-lasting hyper-excitability and persistent memory deficits. Using target site blockers in vivo, we identify multiple developmental programs regulated in parallel by miR-101 to achieve balanced networks. Repression of one target, NKCC1, initiates the switch in γ-aminobutyric acid (GABA) signaling, limits early spontaneous activity, and constrains dendritic growth. Kif1a and Ank2 are targeted to prevent excessive synapse formation. Simultaneous de-repression of these three targets completely phenocopies major dysfunctions produced by miR-101 blockade. Our results provide new mechanistic insight into brain development and suggest novel candidates for therapeutic intervention.

  1. The transactional relationship between parenting and emotion regulation in children with or without developmental delays.

    PubMed

    Norona, Amanda N; Baker, Bruce L

    2014-12-01

    Researchers have identified numerous internal and external factors that contribute to individual differences in emotion regulation (ER) abilities. To extend these findings, we examined the longitudinal effects of a significant external predictor (parenting) on children's ER abilities in the context of an internal predictor (intellectual functioning). We used cross-lagged panel modeling to investigate the transactional relationship between parenting and ER in children with or without developmental delays (DD) across three time points in early and middle childhood (age 3, 5, and 8). Participants were 225 families in the Collaborative Family Study, a longitudinal study of young children with or without DD. Child ER ability and maternal scaffolding skills were coded from mother-child interactions at ages 3, 5, and 8. Compared to children with typical development (TD), children with DD were significantly more dysregulated at all time points, and their mothers exhibited fewer scaffolding behaviors in early childhood. In addition, cross-lagged panel models revealed a significant bidirectional relationship between maternal scaffolding and ER from ages 3 to 5 in the DD group but not the TD group. These findings suggest that scaffolding may be a crucial parenting skill to target in the early treatment of children with ER difficulties.

  2. Calmodulin-binding proteins are developmentally regulated in gametes and embryos of fucoid algae

    SciTech Connect

    Brawley, S.H.; Roberts, D.M.

    1989-02-01

    Calcium-binding proteins and calmodulin-binding proteins were identified in gametes and zygotes of the marine brown algae Fucus vesiculosus, Fucus distichus, and Pelvetia fastigiata using gel (SDS-PAGE) overlay techniques. A calcium current appears to be important during cell polarization in fucoid zygotes, but there are no biochemical data on calcium-binding proteins in these algae. By using a sensitive 45Ca2+ overlay method designed to detect high-affinity calcium-binding proteins, at least 9-11 polypeptides were detected in extracts of fucoid gametes and zygotes. All samples had calcium-binding proteins with apparent molecular weights of about 17 and 30 kDa. A 17-kDa calcium-binding protein was purified by calcium-dependent hydrophobic chromatography and was identified as calmodulin by immunological and enzyme activator criteria. A 125I-calmodulin overlay assay was used to identify potential targets of calmodulin action. Sperm contained one major calmodulin-binding protein of about 45 kDa. Eggs lacked major calmodulin-binding activity. A 72-kDa calmodulin-binding protein was prominent in zygotes from 1-65 hr postfertilization. Both calmodulin-binding proteins showed calcium-dependent binding activity. Overall, the data suggest that the appearance and distribution of certain calcium-binding and calmodulin-binding proteins are under developmental regulation, and may reflect the different roles of calcium during fertilization and early embryogenesis.

  3. RNA editing of the Drosophila para Na(+) channel transcript. Evolutionary conservation and developmental regulation.

    PubMed Central

    Hanrahan, C J; Palladino, M J; Ganetzky, B; Reenan, R A

    2000-01-01

    Post-transcriptional editing of pre-mRNAs through the action of dsRNA adenosine deaminases results in the modification of particular adenosine (A) residues to inosine (I), which can alter the coding potential of the modified transcripts. We describe here three sites in the para transcript, which encodes the major voltage-activated Na(+) channel polypeptide in Drosophila, where RNA editing occurs. The occurrence of RNA editing at the three sites was found to be developmentally regulated. Editing at two of these sites was also conserved across species between the D. melanogaster and D. virilis. In each case, a highly conserved region was found in the intron downstream of the editing site and this region was shown to be complementary to the region of the exonic editing site. Thus, editing at these sites would appear to involve a mechanism whereby the edited exon forms a base-paired secondary structure with the distant conserved noncoding sequences located in adjacent downstream introns, similar to the mechanism shown for A-to-I RNA editing of mammalian glutamate receptor subunits (GluRs). For the third site, neither RNA editing nor the predicted RNA secondary structures were evolutionarily conserved. Transcripts from transgenic Drosophila expressing a minimal editing site construct for this site were shown to faithfully undergo RNA editing. These results demonstrate that Na(+) channel diversity in Drosophila is increased by RNA editing via a mechanism analogous to that described for transcripts encoding mammalian GluRs. PMID:10880477

  4. Developmental regulation of expression of schizophrenia susceptibility genes in the primate hippocampal formation.

    PubMed

    Favre, G; Banta Lavenex, P; Lavenex, P

    2012-10-23

    The hippocampal formation is essential for normal memory function and is implicated in many neurodevelopmental, neurodegenerative and neuropsychiatric disorders. In particular, abnormalities in hippocampal structure and function have been identified in schizophrenic subjects. Schizophrenia has a strong polygenic component, but the role of numerous susceptibility genes in normal brain development and function has yet to be investigated. Here we described the expression of schizophrenia susceptibility genes in distinct regions of the monkey hippocampal formation during early postnatal development. We found that, as compared with other genes, schizophrenia susceptibility genes exhibit a differential regulation of expression in the dentate gyrus, CA3 and CA1, over the course of postnatal development. A number of these genes involved in synaptic transmission and dendritic morphology exhibit a developmental decrease of expression in CA3. Abnormal CA3 synaptic organization observed in schizophrenics might be related to some specific symptoms, such as loosening of association. Interestingly, changes in gene expression in CA3 might occur at a time possibly corresponding to the late appearance of the first clinical symptoms. We also found earlier changes in expression of schizophrenia susceptibility genes in CA1, which might be linked to prodromal psychotic symptoms. A number of schizophrenia susceptibility genes including APOE, BDNF, MTHFR and SLC6A4 are involved in other disorders, and thus likely contribute to nonspecific changes in hippocampal structure and function that must be combined with the dysregulation of other genes in order to lead to schizophrenia pathogenesis.

  5. Fusion safety regulations in the United States: Progress and trends

    SciTech Connect

    DeLooper, J.

    1994-07-01

    This paper explores the issue of regulations as they apply to current and future fusion experimental machines. It addresses fusion regulatory issues, current regulations used for fusion, the Tokamak Fusion Test Reactor experience with regulations, and future regulations to achieve fusion`s safety and environmental potential.

  6. TFIIS-Dependent Non-coding Transcription Regulates Developmental Genome Rearrangements.

    PubMed

    Maliszewska-Olejniczak, Kamila; Gruchota, Julita; Gromadka, Robert; Denby Wilkes, Cyril; Arnaiz, Olivier; Mathy, Nathalie; Duharcourt, Sandra; Bétermier, Mireille; Nowak, Jacek K

    2015-07-01

    Because of their nuclear dimorphism, ciliates provide a unique opportunity to study the role of non-coding RNAs (ncRNAs) in the communication between germline and somatic lineages. In these unicellular eukaryotes, a new somatic nucleus develops at each sexual cycle from a copy of the zygotic (germline) nucleus, while the old somatic nucleus degenerates. In the ciliate Paramecium tetraurelia, the genome is massively rearranged during this process through the reproducible elimination of repeated sequences and the precise excision of over 45,000 short, single-copy Internal Eliminated Sequences (IESs). Different types of ncRNAs resulting from genome-wide transcription were shown to be involved in the epigenetic regulation of genome rearrangements. To understand how ncRNAs are produced from the entire genome, we have focused on a homolog of the TFIIS elongation factor, which regulates RNA polymerase II transcriptional pausing. Six TFIIS-paralogs, representing four distinct families, can be found in P. tetraurelia genome. Using RNA interference, we showed that TFIIS4, which encodes a development-specific TFIIS protein, is essential for the formation of a functional somatic genome. Molecular analyses and high-throughput DNA sequencing upon TFIIS4 RNAi demonstrated that TFIIS4 is involved in all kinds of genome rearrangements, including excision of ~48% of IESs. Localization of a GFP-TFIIS4 fusion revealed that TFIIS4 appears specifically in the new somatic nucleus at an early developmental stage, before IES excision. RT-PCR experiments showed that TFIIS4 is necessary for the synthesis of IES-containing non-coding transcripts. We propose that these IES+ transcripts originate from the developing somatic nucleus and serve as pairing substrates for germline-specific short RNAs that target elimination of their homologous sequences. Our study, therefore, connects the onset of zygotic non coding transcription to the control of genome plasticity in Paramecium, and establishes for

  7. Identification, functional characterization and developmental regulation of sesquiterpene synthases from sunflower capitate glandular trichomes

    PubMed Central

    Göpfert, Jens C; MacNevin, Gillian; Ro, Dae-Kyun; Spring, Otmar

    2009-01-01

    Background Sesquiterpene lactones are characteristic metabolites of Asteraceae (or Compositae) which often display potent bioactivities and are sequestered in specialized organs such as laticifers, resin ducts, and trichomes. For characterization of sunflower sesquiterpene synthases we employed a simple method to isolate pure trichomes from anther appendages which facilitated the identification of these genes and investigation of their enzymatic functions and expression patterns during trichome development. Results Glandular trichomes of sunflower (Helianthus annuus L.) were isolated, and their RNA was extracted to investigate the initial steps of sesquiterpene lactone biosynthesis. Reverse transcription-PCR experiments led to the identification of three sesquiterpene synthases. By combination of in vitro and in vivo characterization of sesquiterpene synthase gene products in Escherichia coli and Saccharomyces cerevisiae, respectively, two enzymes were identified as germacrene A synthases, the key enzymes of sesquiterpene lactone biosynthesis. Due to the very low in vitro activity, the third enzyme was expressed in vivo in yeast as a thioredoxin-fusion protein for functional characterization. In in vivo assays, it was identified as a multiproduct enzyme with the volatile sesquiterpene hydrocarbon δ-cadinene as one of the two main products with α-muuorlene, β-caryophyllene, α-humulene and α-copaene as minor products. The second main compound remained unidentified. For expression studies, glandular trichomes from the anther appendages of sunflower florets were isolated in particular developmental stages from the pre- to the post-secretory phase. All three sesquiterpene synthases were solely upregulated during the biosynthetically active stages of the trichomes. Expression in different aerial plant parts coincided with occurrence and maturity of trichomes. Young roots with root hairs showed expression of the sesquiterpene synthase genes as well. Conclusion This

  8. FKBPL Is a Critical Antiangiogenic Regulator of Developmental and Pathological Angiogenesis

    PubMed Central

    Yakkundi, Anita; Bennett, Rachel; Hernández-Negrete, Ivette; Delalande, Jean-Marie; Hanna, Mary; Lyubomska, Oksana; Arthur, Kenneth; Short, Amy; McKeen, Hayley; Nelson, Laura; McCrudden, Cian M.; McNally, Ross; McClements, Lana; McCarthy, Helen O.; Burns, Alan J.; Bicknell, Roy; Kissenpfennig, Adrien

    2015-01-01

    Objective— The antitumor effects of FK506-binding protein like (FKBPL) and its extracellular role in angiogenesis are well characterized; however, its role in physiological/developmental angiogenesis and the effect of FKBPL ablation has not been evaluated. This is important as effects of some angiogenic proteins are dosage dependent. Here we evaluate the regulation of FKBPL secretion under angiogenic stimuli, as well as the effect of FKBPL ablation in angiogenesis using mouse and zebrafish models. Approach and Results— FKBPL is secreted maximally by human microvascular endothelial cells and fibroblasts, and this was specifically downregulated by proangiogenic hypoxic signals, but not by the angiogenic cytokines, VEGF or IL8. FKBPL’s critical role in angiogenesis was supported by our inability to generate an Fkbpl knockout mouse, with embryonic lethality occurring before E8.5. However, whilst Fkbpl heterozygotic embryos showed some vasculature irregularities, the mice developed normally. In murine angiogenesis models, including the ex vivo aortic ring assay, in vivo sponge assay, and tumor growth assay, Fkbpl+/− mice exhibited increased sprouting, enhanced vessel recruitment, and faster tumor growth, respectively, supporting the antiangiogenic function of FKBPL. In zebrafish, knockdown of zFkbpl using morpholinos disrupted the vasculature, and the phenotype was rescued with hFKBPL. Interestingly, this vessel disruption was ineffective when zcd44 was knocked-down, supporting the dependency of zFkbpl on zCd44 in zebrafish. Conclusions— FKBPL is an important regulator of angiogenesis, having an essential role in murine and zebrafish blood vessel development. Mouse models of angiogenesis demonstrated a proangiogenic phenotype in Fkbpl heterozygotes. PMID:25767277

  9. Estrogen modulates developmentally regulated gene expression in the fetal baboon liver.

    PubMed

    Rosenthal, Miriam D; Albrecht, Eugene D; Pepe, Gerald J

    2004-01-01

    Although estrogen plays a central integrative role in regulating key aspects of placental and fetal endocrine development in the primate, our understanding of the regulation of maturation of the fetal liver is incomplete. In adults, estrogen modulates several aspects of hepatic function. Therefore, the current study determined whether fetal hepatic gene expression development was modulated by estrogen. mRNA differential display was used to identify genes whose expression was altered in fetal livers obtained on d 165 of gestation (term = d 184) from baboons that were untreated or treated on d 60-164 with the aromatase inhibitor CGS 20267 (2 mg/d; sc), which suppressed estrogen levels in the fetus by >95% (p < 0.01). As confirmed by Northern blot, the mRNA levels (ratio to 18s RNA) of metallothionein I (MT-I), porphobilinogen deaminase (PBG-D), and cytochrome P450 2C8 (CYP 2C8) in the livers of estrogen-deprived fetuses were 5-, 12-, and 3-fold higher (p < 0.05) than respective values of untreated fetuses. Moreover, mRNA levels of MT-I and PBG-D, expressed as a ratio to 18s RNA, were 3-fold and 26-fold higher (p < 0.05) on d 60-100 of gestation than on d 165 and in the adult. In contrast, CYP 2C8 mRNA increased 10-fold between d 100 and 165 and was not further altered in adult liver. Immunohistochemistry confirmed expression of MT-I in hepatocytes. Erythropoietic cells, normally present in the fetal baboon liver on d 100 but not on d 165, were also detected on d 165 in animals treated with the aromatase inhibitor. Thus, upregulation of PBG-D mRNA in estrogen-deprived baboons may reflect prolongation of the erythropoietic role of the fetal liver. In summary, these results indicate that the normal developmental change in MT-I, PBG-D, and CYP 2C8 mRNA expression in baboon fetal liver with advancing gestation are dependent on increased secretion of estrogen into the fetus. We suggest, therefore, that estrogen regulates normal development of the primate fetal liver.

  10. Local requirement of the Drosophila insulin binding protein imp-L2 in coordinating developmental progression with nutritional conditions.

    PubMed

    Sarraf-Zadeh, Ladan; Christen, Stefan; Sauer, Uwe; Cognigni, Paola; Miguel-Aliaga, Irene; Stocker, Hugo; Köhler, Katja; Hafen, Ernst

    2013-09-01

    In Drosophila, growth takes place during the larval stages until the formation of the pupa. Starvation delays pupariation to allow prolonged feeding, ensuring that the animal reaches an appropriate size to form a fertile adult. Pupariation is induced by a peak of the steroid hormone ecdysone produced by the prothoracic gland (PG) after larvae have reached a certain body mass. Local downregulation of the insulin/insulin-like growth factor signaling (IIS) activity in the PG interferes with ecdysone production, indicating that IIS activity in the PG couples the nutritional state to development. However, the underlying mechanism is not well understood. In this study we show that the secreted Imaginal morphogenesis protein-Late 2 (Imp-L2), a growth inhibitor in Drosophila, is involved in this process. Imp-L2 inhibits the activity of the Drosophila insulin-like peptides by direct binding and is expressed by specific cells in the brain, the ring gland, the gut and the fat body. We demonstrate that Imp-L2 is required to regulate and adapt developmental timing to nutritional conditions by regulating IIS activity in the PG. Increasing Imp-L2 expression at its endogenous sites using an Imp-L2-Gal4 driver delays pupariation, while Imp-L2 mutants exhibit a slight acceleration of development. These effects are strongly enhanced by starvation and are accompanied by massive alterations of ecdysone production resulting most likely from increased Imp-L2 production by neurons directly contacting the PG and not from elevated Imp-L2 levels in the hemolymph. Taken together our results suggest that Imp-L2-expressing neurons sense the nutritional state of Drosophila larvae and coordinate dietary information and ecdysone production to adjust developmental timing under starvation conditions.

  11. Developmental regulation of the gene for chimeric calcium/calmodulin-dependent protein kinase in anthers

    NASA Technical Reports Server (NTRS)

    Poovaiah, B. W.; Xia, M.; Liu, Z.; Wang, W.; Yang, T.; Sathyanarayanan, P. V.; Franceschi, V. R.

    1999-01-01

    Chimeric Ca(2+)/calmodulin-dependent protein kinase (CCaMK) was cloned from developing anthers of lily (Lilium longiflorum Thumb. cv. Nellie White) and tobacco (Nicotiana tabacum L. cv. Xanthi). Previous biochemical characterization and structure/function studies had revealed that CCaMK has dual modes of regulation by Ca(2+) and Ca(2+)/calmodulin. The unique structural features of CCaMK include a catalytic domain, a calmodulin-binding domain, and a neural visinin-like Ca(2+)-binding domain. The existence of these three features in a single polypeptide distinguishes it from other kinases. Western analysis revealed that CCaMK is expressed in a stage-specific manner in developing anthers. Expression of CCaMK was first detected in pollen mother cells and continued to increase, reaching a peak around the tetrad stage of meiosis. Following microsporogenesis, CCaMK expression rapidly decreased and at later stages of microspore development, no expression was detected. A tobacco genomic clone of CCaMK was isolated and transgenic tobacco plants were produced carrying the CCaMK promoter fused to the beta-glucuronidase reporter gene. Both CCaMK mRNA and protein were detected in the pollen sac and their localizations were restricted to the pollen mother cells and tapetal cells. Consistent results showing a stage-specific expression pattern were obtained by beta-glucuronidase analysis, in-situ hybridization and immunolocalization. The stage- and tissue-specific appearance of CCaMK in anthers suggests that it could play a role in sensing transient changes in free Ca(2+) concentration in target cells, thereby controlling developmental events in the anther.

  12. Developmental Regulation of Diacylglycerol Acyltransferase Family Gene Expression in Tung Tree Tissues

    PubMed Central

    Cao, Heping; Shockey, Jay M.; Klasson, K. Thomas; Chapital, Dorselyn C.; Mason, Catherine B.; Scheffler, Brian E.

    2013-01-01

    Diacylglycerol acyltransferases (DGAT) catalyze the final and rate-limiting step of triacylglycerol (TAG) biosynthesis in eukaryotic organisms. DGAT genes have been identified in numerous organisms. Multiple isoforms of DGAT are present in eukaryotes. We previously cloned DGAT1 and DGAT2 genes of tung tree (Vernicia fordii), whose novel seed TAGs are useful in a wide range of industrial applications. The objective of this study was to understand the developmental regulation of DGAT family gene expression in tung tree. To this end, we first cloned a tung tree gene encoding DGAT3, a putatively soluble form of DGAT that possesses 11 completely conserved amino acid residues shared among 27 DGAT3s from 19 plant species. Unlike DGAT1 and DGAT2 subfamilies, DGAT3 is absent from animals. We then used TaqMan and SYBR Green quantitative real-time PCR, along with northern and western blotting, to study the expression patterns of the three DGAT genes in tung tree tissues. Expression results demonstrate that 1) all three isoforms of DGAT genes are expressed in developing seeds, leaves and flowers; 2) DGAT2 is the major DGAT mRNA in tung seeds, whose expression profile is well-coordinated with the oil profile in developing tung seeds; and 3) DGAT3 is the major form of DGAT mRNA in tung leaves, flowers and immature seeds prior to active tung oil biosynthesis. These results suggest that DGAT2 is probably the major TAG biosynthetic isoform in tung seeds and that DGAT3 gene likely plays a significant role in TAG metabolism in other tissues. Therefore, DGAT2 should be a primary target for tung oil engineering in transgenic organisms. PMID:24146944

  13. Evidence that developmentally regulated control of gene expression by a parvoviral allotropic determinant is particle mediated.

    PubMed Central

    Gardiner, E M; Tattersall, P

    1988-01-01

    An infectious molecular clone of the immunosuppressive strain of the autonomous parvovirus minute virus of mice [MVM(i)] was constructed deriving left-hand terminal sequences from a rare encapsidated plus strand. Progeny virus was shown to package the same proportions of plus and minus strands as did authentic MVM(i) virions. Rescue of virus from this clone also resulted in the repair of a 21-base truncation at the junction between the right-hand end of the viral insert and the vector and generated the same heterogeneous 5' end as is present in standard MVM(i) DNA. Progeny virus rescued by transfection of this clone into mouse cell lines displayed the lymphotropic phenotype characteristic of the parental MVM(i) virus from which it was derived. However, analysis of viral RNA from transfected mouse fibroblasts revealed that the MVM(i) and MVM(p) genomic clones are transcribed at the same low level. Furthermore, transfected fibroblasts yielded similar numbers of infectious centers regardless of which MVM clone was introduced. These results contrast markedly with the different infectivities of MVM(i) and MVM(p) particles and with the observation that viral transcription in fibroblasts productively infected with MVM(p) virions is 100-fold greater than that seen in the restrictive MVM(i) particle-mediated infection. These results suggest that the developmentally regulated intracellular factors controlling host cell susceptibility at the level of viral transcription interact with a component of the incoming viral capsid, rather than with a sequence within the viral DNA. Images PMID:3357208

  14. The promoter of the CD11b gene directs myeloid-specific and developmentally regulated expression.

    PubMed Central

    Shelley, C S; Arnaout, M A

    1991-01-01

    Human CD11b/CD18 (complement receptor type 3) is a member of the beta 2 integrin subfamily which also includes the heterodimers CD11a/CD18 and CD11c/CD18. The CD11 molecules and the common CD18 are the products of different genes that exhibit distinct though overlapping patterns of tissue- and developmental-specific expression. Whereas expression of CD11b and CD11c is almost exclusively restricted to cells of the myeloid lineage, that of CD11a and CD18 is panleukocytic. To begin to understand the mechanisms by which expression of these gene products is restricted to leukocytes and leukocyte subpopulations and to elucidate the mechanisms by which their expression is coordinated, we have cloned and characterized the promoter region of the CD11b gene. A single transcription initiation site has been identified and the region extending 242 base pairs upstream and 71 base pairs downstream of this site has been shown to be sufficient to direct tissue-, cell-, and development-specific expression in vitro, which mimics that of the CD11b gene in vivo. Within this region there are potential binding sites for transcription factors known to be involved in hematopoietic-specific and phorbol ester-inducible gene expression. Further analysis of this region of the CD11b gene and comparison with the promoters of the CD11a, CD11c, and CD18 genes should lead to significant insights into the molecular mechanisms by which these genes are regulated during hematopoietic development and upon activation. Images PMID:1683702

  15. Identity of the NMDA receptor coagonist is synapse specific and developmentally regulated in the hippocampus.

    PubMed

    Le Bail, Matildé; Martineau, Magalie; Sacchi, Silvia; Yatsenko, Natalia; Radzishevsky, Inna; Conrod, Sandrine; Ait Ouares, Karima; Wolosker, Herman; Pollegioni, Loredano; Billard, Jean-Marie; Mothet, Jean-Pierre

    2015-01-13

    NMDA receptors (NMDARs) require the coagonists D-serine or glycine for their activation, but whether the identity of the coagonist could be synapse specific and developmentally regulated remains elusive. We therefore investigated the contribution of D-serine and glycine by recording NMDAR-mediated responses at hippocampal Schaffer collaterals (SC)-CA1 and medial perforant path-dentate gyrus (mPP-DG) synapses in juvenile and adult rats. Selective depletion of endogenous coagonists with enzymatic scavengers as well as pharmacological inhibition of endogenous D-amino acid oxidase activity revealed that D-serine is the preferred coagonist at SC-CA1 mature synapses, whereas, unexpectedly, glycine is mainly involved at mPP-DG synapses. Nevertheless, both coagonist functions are driven by the levels of synaptic activity as inferred by recording long-term potentiation generated at both connections. This regional compartmentalization in the coagonist identity is associated to different GluN1/GluN2A to GluN1/GluN2B subunit composition of synaptic NMDARs. During postnatal development, the replacement of GluN2B- by GluN2A-containing NMDARs at SC-CA1 synapses parallels a change in the identity of the coagonist from glycine to D-serine. In contrast, NMDARs subunit composition at mPP-DG synapses is not altered and glycine remains the main coagonist throughout postnatal development. Altogether, our observations disclose an unprecedented relationship in the identity of the coagonist not only with the GluN2 subunit composition at synaptic NMDARs but also with astrocyte activity in the developing and mature hippocampus that reconciles the complementary functions of D-serine And Glycine In Modulating Nmdars During The Maturation Of Tripartite Glutamatergic Synapses.

  16. Expanding the spectrum of phenotypes associated with germline PIGA mutations: a child with developmental delay, accelerated linear growth, facial dysmorphisms, elevated alkaline phosphatase, and progressive CNS abnormalities.

    PubMed

    van der Crabben, Saskia N; Harakalova, Magdalena; Brilstra, Eva H; van Berkestijn, Frédérique M C; Hofstede, Floris C; van Vught, Adrianus J; Cuppen, Edwin; Kloosterman, Wigard; Ploos van Amstel, Hans Kristian; van Haaften, Gijs; van Haelst, Mieke M

    2014-01-01

    Phosphatidyl inositol glycan (PIG) enzyme subclasses are involved in distinct steps of glycosyl phosphatidyl inositol anchor protein biosynthesis. Glycolsyl phosphatidyl inositol-anchored proteins have heterogeneous functions; they can function as enzymes, adhesion molecules, complement regulators and co-receptors in signal transduction pathways. Germline mutations in genes encoding different members of the PIG family result in diverse conditions with (severe) developmental delay, (neonatal) seizures, hypotonia, CNS abnormalities, growth abnormalities, and congenital abnormalities as hallmark features. The variability of clinical features resembles the typical diversity of other glycosylation pathway deficiencies such as the congenital disorders of glycosylation. Here, we report the first germline missense mutation in the PIGA gene associated with accelerated linear growth, obesity, central hypotonia, severe refractory epilepsy, cardiac anomalies, mild facial dysmorphic features, mildly elevated alkaline phosphatase levels, and CNS anomalies consisting of progressive cerebral atrophy, insufficient myelinization, and cortical MRI signal abnormalities. X-exome sequencing in the proband identified a c.278C>T (p.Pro93Leu) mutation in the PIGA gene. The mother and maternal grandmother were unaffected carriers and the mother showed 100% skewing of the X-chromosome harboring the mutation. These results together with the clinical similarity of the patient reported here and the previously reported patients with a germline nonsense mutation in PIGA support the determination that this mutation caused the phenotype in this family.

  17. Have studies of the developmental regulation of behavioral phenotypes revealed the mechanisms of gene-environment interactions?

    PubMed Central

    Hall, F. Scott; Perona, Maria T. G.

    2012-01-01

    This review addresses the recent convergence of our long-standing knowledge of the regulation of behavioral phenotypes by developmental experience with recent advances in our understanding of mechanisms regulating gene expression. This review supports a particular perspective on the developmental regulation of behavioral phenotypes: That the role of common developmental experiences (e.g. maternal interactions, peer interactions, exposure to a complex environment, etc.) is to fit individuals to the circumstances of their lives within bounds determined by long-standing (evolutionary) mechanisms that have shaped responses to critical and fundamental types of experience via those aspects of gene structure that regulate gene expression. The phenotype of a given species is not absolute for a given genotype but rather variable within bounds that are determined by mechanisms regulated by experience (e.g. epigenetic mechanisms). This phenotypic variation is not necessarily random, or evenly distributed along a continuum of description or measurement, but often highly disjointed, producing distinct, even opposing, phenotypes. The potentiality for these varying phenotypes is itself the product of evolution, the potential for alternative phenotypes itself conveying evolutionary advantage. Examples of such phenotypic variation, resulting from environmental or experiential influences, have a long history of study in neurobiology, and a number of these will be discussed in this review: neurodevelopmental experiences that produce phenotypic variation in visual perception, cognitive function, and emotional behavior. Although other examples will be discussed, particular emphasis will be made on the role of social behavior on neurodevelopment and phenotypic determination. It will be argued that an important purpose of some aspects of social behavior is regulation of neurobehavioral phenotypes by experience via genetic regulatory mechanisms. PMID:22643448

  18. Torpedo electromotor system development: developmentally regulated neuronotrophic activities of electric organ tissue.

    PubMed

    Richardson, G P; Rinschen, B; Fox, G Q

    1985-01-15

    Explant cultures of electric lobe from 45-60 mm stage Torpedo embryos and both ganglionic and dissociated cell cultures prepared from 8-day chick ciliary ganglia have been used to determine whether the electric organs of Torpedo marmorata contain developmentally regulated neuronotrophic activity. Electric lobe explants were evaluated by measuring their neurone density, choline acetyltransferase (CAT0, and low salt, Triton X-100-soluble protein contents. Addition of soluble extracts prepared from the electric organs of late stage embryos (85-105 mm) to standard medium results in the maintenance of nearly theoretical neurone densities in electric lobe explants during a 7-day culture period. Soluble electric organ extracts from early embryonic stages (42-59 mm) do not increase neurone density relative to control cultures but cause an elevation in the CAT content of the explants over control values. On the basis of this analysis it is concluded (1) that late embryonic stage and adult electric organs contain neuronotrophic activity that allows electromotor neurones to survive in vitro and (2) that activity increases rapidly in the electric organs between the 59 nd 72 mm stages of development at a time when rapid increases in postsynaptic membrane markers in the electric organs occur and when peripheral synaptogenesis begins. The activity of late stage embryonic electric organs is heat stable and lost on dialysis. Using ciliary ganglion explants and evaluating both the initial fibre outgrowth and the CAT content after 4 days in vitro, trophic activity is found to be maximal at early embryonic stages (45-55 mm) and to decline thereafter. It is shown that the decline in activity is not due to an increase in toxicity. Using established dissociated ganglionic cell survival assays the specific activity of neuronotrophic factors allowing survival is constant between the 45 and 73 mm stages in the electric organs and then rapidly declines, but activity per electric organ

  19. TFIIS-Dependent Non-coding Transcription Regulates Developmental Genome Rearrangements

    PubMed Central

    Maliszewska-Olejniczak, Kamila; Gruchota, Julita; Gromadka, Robert; Denby Wilkes, Cyril; Arnaiz, Olivier; Mathy, Nathalie; Duharcourt, Sandra; Bétermier, Mireille; Nowak, Jacek K.

    2015-01-01

    Because of their nuclear dimorphism, ciliates provide a unique opportunity to study the role of non-coding RNAs (ncRNAs) in the communication between germline and somatic lineages. In these unicellular eukaryotes, a new somatic nucleus develops at each sexual cycle from a copy of the zygotic (germline) nucleus, while the old somatic nucleus degenerates. In the ciliate Paramecium tetraurelia, the genome is massively rearranged during this process through the reproducible elimination of repeated sequences and the precise excision of over 45,000 short, single-copy Internal Eliminated Sequences (IESs). Different types of ncRNAs resulting from genome-wide transcription were shown to be involved in the epigenetic regulation of genome rearrangements. To understand how ncRNAs are produced from the entire genome, we have focused on a homolog of the TFIIS elongation factor, which regulates RNA polymerase II transcriptional pausing. Six TFIIS-paralogs, representing four distinct families, can be found in P. tetraurelia genome. Using RNA interference, we showed that TFIIS4, which encodes a development-specific TFIIS protein, is essential for the formation of a functional somatic genome. Molecular analyses and high-throughput DNA sequencing upon TFIIS4 RNAi demonstrated that TFIIS4 is involved in all kinds of genome rearrangements, including excision of ~48% of IESs. Localization of a GFP-TFIIS4 fusion revealed that TFIIS4 appears specifically in the new somatic nucleus at an early developmental stage, before IES excision. RT-PCR experiments showed that TFIIS4 is necessary for the synthesis of IES-containing non-coding transcripts. We propose that these IES+ transcripts originate from the developing somatic nucleus and serve as pairing substrates for germline-specific short RNAs that target elimination of their homologous sequences. Our study, therefore, connects the onset of zygotic non coding transcription to the control of genome plasticity in Paramecium, and establishes for

  20. Assessment of Reproductive and Developmental Toxicity of Mixtures of Regulated Drinking Water Chlorination By-Products in a Multigenerational Rat Bioassay

    EPA Science Inventory

    Epidemiological and animal toxicity studies have raised concerns regarding possible adverse reproductive and developmental effects of disinfection by-products (DBPs) in drinking water. To address these concerns, we provided mixtures of the regulated trihalomethanes (THMs; chlorof...

  1. Developmental regulation and modulation of apoptotic genes expression in sheep oocytes and embryos cultured in vitro with L-carnitine.

    PubMed

    Mishra, A; Reddy, I J; Gupta, Psp; Mondal, S

    2016-12-01

    The objective of this study was to find out the impact of L-carnitine (10 mM) on developmental regulation of preimplantation sheep embryos cultured in vitro when supplemented in maturation medium and post-fertilization medium separately. Subsequent objective was to observe the L-carnitine-mediated alteration in expression of apoptotic genes (Bcl2, Bax, Casp3 and PCNA) in sheep oocytes and developing embryos produced in vitro. Oocytes matured with L-carnitine showed significantly (p < .05) higher cleavage (67.23% vs 43.12%), morula (47.65% vs 28.58%) and blastocysts (32.12% vs 13.24%) percentage as compared to presumptive zygotes cultured with L-carnitine during post-fertilization period. So it is suggested to use L-carnitine during maturation than post-fertilization period. Antiapoptotic and proliferative effects of L-carnitine were confirmed by inducing culture medium with actinomycin D (apoptotic agent) and TNFα (antiproliferative agent), respectively, with and without L-carnitine. Oocytes and embryos cultured with actinomycin D and TNFα showed developmental arrest with significant (p < .05) decrease in morula and blastocysts percentage but supplementation of L-carnitine to actinomycin D and TNFα induced culture medium showed similar result as that of control. L-carnitine supplementation during IVM significantly (p < .05) upregulated the expression of Bcl2 and PCNA genes in majority of the developmental stages. Although L-carnitine upregulated the expression of Bax in initial developmental stages but downregulated at latter part, whereas the expression of Casp3 was upregulated upto 16-cell stage but after that there was no difference in expression. Expression of GAPDH gene was not affected by L-carnitine supplementation. In conclusion, L-carnitine acted as an antiapoptotic and proliferative compound during embryo development and supplementation of L-carnitine during IVM altered the expression of apoptotic genes in the developmental stages of embryos.

  2. Will new disposal regulations undo decades of progress?

    SciTech Connect

    Ward, J.

    2009-07-01

    In 1980, the Belville Amendments to RCRA instructed EPA to 'conduct a detailed and comprehensive study and submit a report' to Congress on the 'adverse effects on human health and the environment, if any, of the disposal and utilization' of coal ash. In both 1988 and 1999, EPA submitted reports to Congress and recommended coal ash should not be regulated as hazardous waste. After the failure of a Tennesse power plant's coal ash disposal facility, EPA will be proposing new disposal regulations.

  3. Developmental Regulation of Lectin and Alliinase Synthesis in Garlic Bulbs and Leaves.

    PubMed Central

    Smeets, K.; Van Damme, EJM.; Peumans, W. J.

    1997-01-01

    Using a combination of northern blot analysis and sodium dodecyl sulfate-polyacrylamide gel electrophoresis, a detailed study was made of the temporal and spatial regulation of garlic (Allium sativum L.) lectins and alliinase throughout the life cycle of the plant. The two bulb-specific lectins (ASAI and ASAII), which are the most predominant bulb proteins, accumulate exclusively in the developing garlic cloves and progressively disappear when the old clove is consumed by the plant. On the basis of these observations, ASAI and ASAII can be regarded as typical vegetative storage proteins. The leaf-specific lectin (ASAL), on the contrary, is specifically synthesized in young leaves and remains present until withering. Because ASAL is only a minor protein, it probably fulfills a specific function in the plant. Unlike the lectins, alliinase is present in large quantities in bulbs as well as in leaves. Moreover, intact alliinase mRNAs are present in both tissues as long as they contain living cells. The latter observation is in good agreement with the possible involvement of alliinase in the plant's defense against pathogens and/or predators. PMID:12223641

  4. Developmental Regulation of a Plasma Membrane Arabinogalactan Protein Epitope in Oilseed Rape Flowers.

    PubMed Central

    Pennell, RI; Janniche, L; Kjellbom, P; Scofield, GN; Peart, JM; Roberts, K

    1991-01-01

    We have identified and characterized the temporal and spatial regulation of a plasma membrane arabinogalactan protein epitope during development of the aerial parts of oilseed rape using the monoclonal antibody JIM8. The JIM8 epitope is expressed by the first cells of the embryo and by certain cells in the sexual organs of flowers. During embryogenesis, the JIM8 epitope ceases to be expressed by the embryo proper but is still found in the suspensor. During differentiation of the stamens and carpels, expression of the JIM8 epitope progresses from one cell type to another, ultimately specifying the endothecium and sperm cells, the nucellar epidermis, synergid cells, and the egg cell. This complex temporal sequence demonstrates rapid turnover of the JIM8 epitope. There is no direct evidence for any cell-inductive process in plant development. However, if cell-cell interactions exist in plants and participate in flower development, the JIM8 epitope may be a marker for one set of them. PMID:12324592

  5. Developmental and tumoral vascularization is regulated by G protein–coupled receptor kinase 2

    PubMed Central

    Rivas, Verónica; Carmona, Rita; Muñoz-Chápuli, Ramón; Mendiola, Marta; Nogués, Laura; Reglero, Clara; Miguel-Martín, María; García-Escudero, Ramón; Dorn, Gerald W.; Hardisson, David; Mayor, Federico; Penela, Petronila

    2013-01-01

    Tumor vessel dysfunction is a pivotal event in cancer progression. Using an in vivo neovascularization model, we identified G protein–coupled receptor kinase 2 (GRK2) as a key angiogenesis regulator. An impaired angiogenic response involving immature vessels was observed in mice hemizygous for Grk2 or in animals with endothelium-specific Grk2 silencing. ECs isolated from these animals displayed intrinsic alterations in migration, TGF-β signaling, and formation of tubular networks. Remarkably, an altered pattern of vessel growth and maturation was detected in postnatal retinas from endothelium-specific Grk2 knockout animals. Mouse embryos with systemic or endothelium-selective Grk2 ablation had marked vascular malformations involving impaired recruitment of mural cells. Moreover, decreased endothelial Grk2 dosage accelerated tumor growth in mice, along with reduced pericyte vessel coverage and enhanced macrophage infiltration, and this transformed environment promoted decreased GRK2 in ECs and human breast cancer vessels. Our study suggests that GRK2 downregulation is a relevant event in the tumoral angiogenic switch. PMID:24135140

  6. Developmental link between sex and nutrition; doublesex regulates sex-specific mandible growth via juvenile hormone signaling in stag beetles.

    PubMed

    Gotoh, Hiroki; Miyakawa, Hitoshi; Ishikawa, Asano; Ishikawa, Yuki; Sugime, Yasuhiro; Emlen, Douglas J; Lavine, Laura C; Miura, Toru

    2014-01-01

    Sexual dimorphisms in trait expression are widespread among animals and are especially pronounced in ornaments and weapons of sexual selection, which can attain exaggerated sizes. Expression of exaggerated traits is usually male-specific and nutrition sensitive. Consequently, the developmental mechanisms generating sexually dimorphic growth and nutrition-dependent phenotypic plasticity are each likely to regulate the expression of extreme structures. Yet we know little about how either of these mechanisms work, much less how they might interact with each other. We investigated the developmental mechanisms of sex-specific mandible growth in the stag beetle Cyclommatus metallifer, focusing on doublesex gene function and its interaction with juvenile hormone (JH) signaling. doublesex genes encode transcription factors that orchestrate male and female specific trait development, and JH acts as a mediator between nutrition and mandible growth. We found that the Cmdsx gene regulates sex differentiation in the stag beetle. Knockdown of Cmdsx by RNA-interference in both males and females produced intersex phenotypes, indicating a role for Cmdsx in sex-specific trait growth. By combining knockdown of Cmdsx with JH treatment, we showed that female-specific splice variants of Cmdsx contribute to the insensitivity of female mandibles to JH: knockdown of Cmdsx reversed this pattern, so that mandibles in knockdown females were stimulated to grow by JH treatment. In contrast, mandibles in knockdown males retained some sensitivity to JH, though mandibles in these individuals did not attain the full sizes of wild type males. We suggest that moderate JH sensitivity of mandibular cells may be the default developmental state for both sexes, with sex-specific Dsx protein decreasing sensitivity in females, and increasing it in males. This study is the first to demonstrate a causal link between the sex determination and JH signaling pathways, which clearly interact to determine the

  7. Developmental Link between Sex and Nutrition; doublesex Regulates Sex-Specific Mandible Growth via Juvenile Hormone Signaling in Stag Beetles

    PubMed Central

    Gotoh, Hiroki; Miyakawa, Hitoshi; Ishikawa, Asano; Ishikawa, Yuki; Sugime, Yasuhiro; Emlen, Douglas J.; Lavine, Laura C.; Miura, Toru

    2014-01-01

    Sexual dimorphisms in trait expression are widespread among animals and are especially pronounced in ornaments and weapons of sexual selection, which can attain exaggerated sizes. Expression of exaggerated traits is usually male-specific and nutrition sensitive. Consequently, the developmental mechanisms generating sexually dimorphic growth and nutrition-dependent phenotypic plasticity are each likely to regulate the expression of extreme structures. Yet we know little about how either of these mechanisms work, much less how they might interact with each other. We investigated the developmental mechanisms of sex-specific mandible growth in the stag beetle Cyclommatus metallifer, focusing on doublesex gene function and its interaction with juvenile hormone (JH) signaling. doublesex genes encode transcription factors that orchestrate male and female specific trait development, and JH acts as a mediator between nutrition and mandible growth. We found that the Cmdsx gene regulates sex differentiation in the stag beetle. Knockdown of Cmdsx by RNA-interference in both males and females produced intersex phenotypes, indicating a role for Cmdsx in sex-specific trait growth. By combining knockdown of Cmdsx with JH treatment, we showed that female-specific splice variants of Cmdsx contribute to the insensitivity of female mandibles to JH: knockdown of Cmdsx reversed this pattern, so that mandibles in knockdown females were stimulated to grow by JH treatment. In contrast, mandibles in knockdown males retained some sensitivity to JH, though mandibles in these individuals did not attain the full sizes of wild type males. We suggest that moderate JH sensitivity of mandibular cells may be the default developmental state for both sexes, with sex-specific Dsx protein decreasing sensitivity in females, and increasing it in males. This study is the first to demonstrate a causal link between the sex determination and JH signaling pathways, which clearly interact to determine the

  8. Developmental lead exposure attenuates methamphetamine dose-effect self-administration performance and progressive ratio responding in the male rat.

    PubMed

    Rocha, Angelica; Valles, Rodrigo; Hart, Nigel; Bratton, Gerald R; Nation, Jack R

    2008-06-01

    Perinatal (gestation/lactation) lead exposure modifies the reinforcement efficacy of various psychoactive drugs (e.g., cocaine, opiates) across the phases of initial selection, use, and abuse [Nation J.R., Cardon A.L., Heard H.M., Valles R., Bratton G.R. Perinatal lead exposure and relapse to drug-seeking behavior in the rat: a cocaine reinstatement study. Psychopharmacol 2003;168: 236-243.; Nation J.R., Smith K.R., Bratton G.R. Early developmental lead exposure increases sensitivity to cocaine in a self-administration paradigm. Pharmacol Biochem Behave 2004; 77: 127-13; Rocha A., Valles R., Cardon A.L., Bratton G.R., Nation J.R. Enhanced acquisition of cocaine self-administration in rats developmentally exposed to lead. Neuropsychopharmacol 2005; 30: 2058-2064.]. However, changes in sensitivity to methamphetamine across the phases of drug abuse have not been examined in animals perinatally exposed to lead. Because the mainstream popularity of methamphetamine in the United States is increasing and lead exposure continues to be widespread, an examination of this drug and how it may be modified by perinatal exposure to lead is warranted. The studies reported here examined the effects of perinatal lead exposure on adult self-administration of intravenous (i.v.) methamphetamine across the maintenance phase of drug addiction. Experiment 1 examined dose-effect patterns in control and lead-exposed animals. Experiment 2 evaluated control and lead-exposed animals in a progressive ratio task. Female rats were administered a 16-mg lead or a control solution for 30 days prior to breeding with non-exposed males. Exposure continued through pregnancy and lactation and was discontinued at weaning (postnatal day [PND] 21). Animals born to control or lead-exposed dams received indwelling jugular catheters as adults (PND 70) and subsequently were randomly assigned to one of the two studies, using only one male rat per litter for each study. The data showed a general attenuation of

  9. The Role of pH Regulation in Cancer Progression.

    PubMed

    McIntyre, Alan; Harris, Adrian L

    Frequently observed phenotypes of tumours include high metabolic activity, hypoxia and poor perfusion; these act to produce an acidic microenvironment. Cellular function depends on pH homoeostasis, and thus, tumours become dependent on pH regulatory mechanisms. Many of the proteins involved in pH regulation are highly expressed in tumours, and their expression is often of prognostic significance. The more acidic tumour microenvironment also has important implications with regard to chemotherapeutic and radiotherapeutic interventions. In addition, we review pH-sensing mechanisms, the role of pH regulation in tumour phenotype and the use of pH regulatory mechanisms as therapeutic targets.

  10. Progress in the function and regulation of ADP-Ribosylation.

    PubMed

    Hottiger, Michael O; Boothby, Mark; Koch-Nolte, Friedrich; Lüscher, Bernhard; Martin, Niall M B; Plummer, Ruth; Wang, Zhao-Qi; Ziegler, Mathias

    2011-05-24

    Adenosine 5'-diphosphate (ADP)-ribosylation is a protein posttranslational modification that is catalyzed by ADP-ribosyltransferases (ARTs), using nicotinamide adenine dinucleotide (NAD(+)) as a substrate. Mono-ribosylation can be extended into polymers of ADP-ribose (PAR). Poly(ADP-ribosyl)polymerase (PARP) 1, the best-characterized cellular enzyme catalyzing this process, is the prototypical member of a family of mono- and poly(ADP-ribosyl)transferases. The physiological consequences of ADP-ribosylation are inadequately understood. PARP2010, the 18th International Conference on ADP-Ribosylation, attracted scientists from all over the world to Zurich, Switzerland. Highlights from this meeting include promising clinical trials with PARP inhibitors and new insights into cell, structural, and developmental biology of ARTs and the (glyco)hydrolase proteins that catalyze de-ADP-ribosylation of mono- or poly-ADP-ribosylated proteins. Moreover, potential links to the NAD-dependent sirtuin family were explored on the basis of a shared dependence on cellular NAD(+) concentrations and the relationship of ADP-ribosylation with intermediary metabolism and cellular energetics.

  11. Developmentally regulated HEART STOPPER, a mitochondrially targeted L18 ribosomal protein gene, is required for cell division, differentiation, and seed development in Arabidopsis

    PubMed Central

    Zhang, Hongyu; Luo, Ming; Day, Robert C.; Talbot, Mark J.; Ivanova, Aneta; Ashton, Anthony R.; Chaudhury, Abed M.; Macknight, Richard C.; Hrmova, Maria; Koltunow, Anna M.

    2015-01-01

    Evidence is presented for the role of a mitochondrial ribosomal (mitoribosomal) L18 protein in cell division, differentiation, and seed development after the characterization of a recessive mutant, heart stopper (hes). The hes mutant produced uncellularized endosperm and embryos arrested at the late globular stage. The mutant embryos differentiated partially on rescue medium with some forming callus. HES (At1g08845) encodes a mitochondrially targeted member of a highly diverged L18 ribosomal protein family. The substitution of a conserved amino residue in the hes mutant potentially perturbs mitoribosomal function via altered binding of 5S rRNA and/or influences the stability of the 50S ribosomal subunit, affecting mRNA binding and translation. Consistent with this, marker genes for mitochondrial dysfunction were up-regulated in the mutant. The slow growth of the endosperm and embryo indicates a defect in cell cycle progression, which is evidenced by the down-regulation of cell cycle genes. The down-regulation of other genes such as EMBRYO DEFECTIVE genes links the mitochondria to the regulation of many aspects of seed development. HES expression is developmentally regulated, being preferentially expressed in tissues with active cell division and differentiation, including developing embryos and the root tips. The divergence of the L18 family, the tissue type restricted expression of HES, and the failure of other L18 members to complement the hes phenotype suggest that the L18 proteins are involved in modulating development. This is likely via heterogeneous mitoribosomes containing different L18 members, which may result in differential mitochondrial functions in response to different physiological situations during development. PMID:26105995

  12. Regulation of alcohol fermentation in Escherichia coli: (Final) progress report, July 1985--June 1988

    SciTech Connect

    Clark, D.P.

    1988-01-01

    This report describes progress in research on the biochemical degradation of alcohols by genetically modified bacteria. Topics include the genetics of the adh system, the characterization of the ADH/ACDH protein, the regulation of the adh gene, the isolation of two lactate dehydrogenase mutants, mutations that affect anaerobic growth, and regulation of the anaerobic gene fusions. (TEM)

  13. Chromatin remodelling and antisense-mediated up-regulation of the developmental switch gene eud-1 control predatory feeding plasticity

    PubMed Central

    Serobyan, Vahan; Xiao, Hua; Namdeo, Suryesh; Rödelsperger, Christian; Sieriebriennikov, Bogdan; Witte, Hanh; Röseler, Waltraud; Sommer, Ralf J.

    2016-01-01

    Phenotypic plasticity has been suggested to act through developmental switches, but little is known about associated molecular mechanisms. In the nematode Pristionchus pacificus, the sulfatase eud-1 was identified as part of a developmental switch controlling mouth-form plasticity governing a predatory versus bacteriovorous mouth-form decision. Here we show that mutations in the conserved histone-acetyltransferase Ppa-lsy-12 and the methyl-binding-protein Ppa-mbd-2 mimic the eud-1 phenotype, resulting in the absence of one mouth-form. Mutations in both genes cause histone modification defects and reduced eud-1 expression. Surprisingly, Ppa-lsy-12 mutants also result in the down-regulation of an antisense-eud-1 RNA. eud-1 and antisense-eud-1 are co-expressed and further experiments suggest that antisense-eud-1 acts through eud-1 itself. Indeed, overexpression of the antisense-eud-1 RNA increases the eud-1-sensitive mouth-form and extends eud-1 expression. In contrast, this effect is absent in eud-1 mutants indicating that antisense-eud-1 positively regulates eud-1. Thus, chromatin remodelling and antisense-mediated up-regulation of eud-1 control feeding plasticity in Pristionchus. PMID:27487725

  14. Improving child self-regulation and parenting in families of pre-kindergarten children with developmental disabilities and behavioral difficulties.

    PubMed

    Pears, Katherine C; Kim, Hyoun K; Healey, Cynthia V; Yoerger, Karen; Fisher, Philip A

    2015-02-01

    The transition to school may be particularly difficult for children with developmental disabilities and behavioral difficulties. Such children are likely to experience problems with self-regulation skills, which are critical to school adjustment. Additionally, inconsistent discipline practices and low parental involvement in children's schooling may contribute to a poor transition to school. This study employed a randomized clinical trial to examine the effects of a school readiness intervention that focused on children's self-regulation skills as well as parenting and parental involvement in school. Results showed that the intervention had positive effects on children's self-regulation in kindergarten as measured by teacher and observer reports. Additionally, the intervention significantly reduced ineffective parenting prior to school entry, which in turn affected parental involvement. This finding is significant because it demonstrates that parental involvement in school may be increased by efforts to improve parenting skills in general. Overall, the study demonstrated that school adjustment across kindergarten among children with developmental disabilities and behavioral difficulties can be enhanced through an intervention aimed specifically at improving school readiness skills.

  15. Regulation of cancer progression by β-endorphin neuron

    PubMed Central

    Sarkar, Dipak K.; Murugan, Sengottuvelan; Zhang, Changqing; Boyadjieva, Nadka

    2011-01-01

    It is becoming increasingly clear that stressful life events can impact cancer growth and metastasis by modulating nervous, endocrine and immune systems. The purpose of this review is to briefly describe the process by which stress may potentiate carcinogenesis and how reducing body stress may prevent cancer growth and progression. The opioid peptide beta-endorphin (BEP) plays a critical role in brining the stress axis to a state of homeostasis. We have recently shown that enhancement of endogenous levels of BEP in the hypothalamus via BEP neuron transplantation suppresses stress response, promotes immune function and reduces the incidence of cancer in rat models of prostate and breast cancers. The cancer preventive effect of BEP is mediated through the suppression of sympathetic neuronal function that results in an increased peripheral natural killer (NK) cell and macrophage activities, elevated levels of anti-inflammatory cytokines and reduced levels of inflammatory cytokines. BEP inhibition of tumor progression also involves alteration in the tumor microenvironment, possibly due to suppression of catecholamine and inflammatory cytokines production that are known to alter DNA repair, cell-matrix attachments, angiogenic process and epithelial-mesenchymal transition. Thus, BEP cell therapy may offer some therapeutic value in cancer prevention. PMID:22287549

  16. PHD2: from hypoxia regulation to disease progression.

    PubMed

    Meneses, Ana M; Wielockx, Ben

    2016-01-01

    Oxygen represents one of the major molecules required for the development and maintenance of life. An adequate response to hypoxia is therefore required for the functioning of the majority of living organisms and relies on the activation of the hypoxia-inducible factor (HIF) pathway. HIF prolyl hydroxylase domain-2 (PHD2) has long been recognized as the major regulator of this response, controlling a myriad of outcomes that range from cell death to proliferation. However, this enzyme has been associated with more pathways, making the role of this protein remarkably complex under distinct pathologies. While a protective role seems to exist in physiological conditions such as erythropoiesis; the picture is more complex during pathologies such as cancer. Since the regulation of this enzyme and its closest family members is currently considered as a possible therapy for various diseases, understanding the different particular roles of this protein is essential.

  17. PHD2: from hypoxia regulation to disease progression

    PubMed Central

    Meneses, Ana M; Wielockx, Ben

    2016-01-01

    Oxygen represents one of the major molecules required for the development and maintenance of life. An adequate response to hypoxia is therefore required for the functioning of the majority of living organisms and relies on the activation of the hypoxia-inducible factor (HIF) pathway. HIF prolyl hydroxylase domain-2 (PHD2) has long been recognized as the major regulator of this response, controlling a myriad of outcomes that range from cell death to proliferation. However, this enzyme has been associated with more pathways, making the role of this protein remarkably complex under distinct pathologies. While a protective role seems to exist in physiological conditions such as erythropoiesis; the picture is more complex during pathologies such as cancer. Since the regulation of this enzyme and its closest family members is currently considered as a possible therapy for various diseases, understanding the different particular roles of this protein is essential. PMID:27800508

  18. Parental Influences on Children's Self-Regulation of Energy Intake: Insights from Developmental Literature on Emotion Regulation

    PubMed Central

    Frankel, Leslie A.; Hughes, Sheryl O.; O'Connor, Teresia M.; Power, Thomas G.; Fisher, Jennifer O.; Hazen, Nancy L.

    2012-01-01

    The following article examines the role of parents in the development of children's self-regulation of energy intake. Various paths of parental influence are offered based on the literature on parental influences on children's emotion self-regulation. The parental paths include modeling, responses to children's behavior, assistance in helping children self-regulate, and motivating children through rewards and punishments. Additionally, sources of variation in parental influences on regulation are examined, including parenting style, child temperament, and child-parent attachment security. Parallels in the nature of parents' role in socializing children's regulation of emotions and energy intake are examined. Implications for future research are discussed. PMID:22545206

  19. TRAIP regulates replication fork recovery and progression via PCNA

    PubMed Central

    Feng, Wanjuan; Guo, Yingying; Huang, Jun; Deng, Yiqun; Zang, Jianye; Huen, Michael Shing-Yan

    2016-01-01

    PCNA is a central scaffold that coordinately assembles replication and repair machineries at DNA replication forks for faithful genome duplication. Here, we describe TRAIP (RNF206) as a novel PCNA-interacting factor that has important roles during mammalian replicative stress responses. We show that TRAIP encodes a nucleolar protein that migrates to stalled replication forks, and that this is accomplished by its targeting of PCNA via an evolutionarily conserved PIP box on its C terminus. Accordingly, inactivation of TRAIP or its interaction with the PCNA clamp compromised replication fork recovery and progression, and leads to chromosome instability. Together, our findings establish TRAIP as a component of the mammalian replicative stress response network, and implicate the TRAIP-PCNA axis in recovery of stalled replication forks. PMID:27462463

  20. Developmental fluoxetine exposure increases behavioral despair and alters epigenetic regulation of the hippocampal BDNF gene in adult female offspring.

    PubMed

    Boulle, Fabien; Pawluski, Jodi L; Homberg, Judith R; Machiels, Barbie; Kroeze, Yvet; Kumar, Neha; Steinbusch, Harry W M; Kenis, Gunter; van den Hove, Daniel L A

    2016-04-01

    A growing number of infants are exposed to selective serotonin reuptake inhibitor (SSRI) medications during the perinatal period. Perinatal exposure to SSRI medications alter neuroplasticity and increase depressive- and anxiety-related behaviors, particularly in male offspring as little work has been done in female offspring to date. The long-term effects of SSRI on development can also differ with previous exposure to prenatal stress, a model of maternal depression. Because of the limited work done on the role of developmental SSRI exposure on neurobehavioral outcomes in female offspring, the aim of the present study was to investigate how developmental fluoxetine exposure affects anxiety and depression-like behavior, as well as the regulation of hippocampal brain-derived neurotrophic factor (BDNF) signaling in the hippocampus of adult female offspring. To do this female Sprague-Dawley rat offspring were exposed to prenatal stress and fluoxetine via the dam, for a total of four groups of female offspring: 1) No Stress+Vehicle, 2) No Stress+Fluoxetine, 3) Prenatal Stress+Vehicle, and 4) Prenatal Stress+Fluoxetine. Primary results show that, in adult female offspring, developmental SSRI exposure significantly increases behavioral despair measures on the forced swim test, decreases hippocampal BDNF exon IV mRNA levels, and increases levels of the repressive histone 3 lysine 27 tri-methylated mark at the corresponding promoter. There was also a significant negative correlation between hippocampal BDNF exon IV mRNA levels and immobility in the forced swim test. No effects of prenatal stress or developmental fluoxetine exposure were seen on tests of anxiety-like behavior. This research provides important evidence for the long-term programming effects of early-life exposure to SSRIs on female offspring, particularily with regard to affect-related behaviors and their underlying molecular mechanisms.

  1. Embryonic Mechanical and Soluble Cues Regulate Tendon Progenitor Cell Gene Expression as a Function of Developmental Stage and Anatomical Origin

    PubMed Central

    Brown, Jeffrey P; Finley, Violet G; Kuo, Catherine K

    2014-01-01

    Stem cell-based engineering strategies for tendons have yet to yield a normal functional tissue, due in part to a need for tenogenic factors. Additionally, the ability to evaluate differentiation has been challenged by a lack of markers for differentiation. We propose to inform tendon regeneration with developmental cues involved in normal tissue formation and with phenotypic markers that are characteristic of differentiating tendon progenitor cells (TPCs). Mechanical forces, fibroblast growth factor (FGF)-4 and transforming growth factor (TGF)-β2 are implicated in embryonic tendon development, yet the isolated effects of these factors on differentiating TPCs are unknown. Additionally, developmental mechanisms vary between limb and axial tendons, suggesting the respective cell types are programmed to respond uniquely to exogenous factors. To characterize developmental cues and benchmarks for differentiation toward limb vs. axial phenotypes, we dynamically loaded and treated TPCs with growth factors and assessed gene expression profiles as a function of developmental stage and anatomical origin. Based on scleraxis expression, TGFβ2 was tenogenic for TPCs at all stages, while loading was for late-stage cells only, and FGF4 had no effect despite regulation of other genes. When factors were combined, TGF 2 continued to be tenogenic, while FGF4 appeared anti-tenogenic. Various treatments elicited distinct responses by axial vs. limb TPCs of specific stages. These results identified tenogenic factors, suggest tendon engineering strategies should be customized for tissues by anatomical origin, and provide stage-specific gene expression profiles of limb and axial TPCs as benchmarks with which to monitor tenogenic differentiation of stem cells. PMID:24231248

  2. Progressive lung cancer determined by expression profiling and transcriptional regulation.

    PubMed

    Han, Namshik; Dol, Zulkifli; Vasieva, Olga; Hyde, Russell; Liloglou, Triantafillos; Raji, Olaide; Brambilla, Elisabeth; Brambilla, Christian; Martinet, Yves; Sozzi, Gabriella; Risch, Angela; Montuenga, Luis M; Brass, Andy; Field, John K

    2012-07-01

    Clinically, our ability to predict disease outcome for patients with early stage lung cancer is currently poor. To address this issue, tumour specimens were collected at surgery from non-small cell lung cancer (NSCLC) patients as part of the European Early Lung Cancer (EUELC) consortium. The patients were followed-up for three years post-surgery and patients who suffered progressive disease (PD, tumour recurrence, metastasis or a second primary) or remained disease-free (DF) during follow-up were identified. RNA from both tumour and adjacent-normal lung tissue was extracted from patients and subjected to microarray expression profiling. These samples included 36 adenocarcinomas and 23 squamous cell carcinomas from both PD and DF patients. The microarray data was subject to a series of systematic bioinformatics analyses at gene, network and transcription factor levels. The focus of these analyses was 2-fold: firstly to determine whether there were specific biomarkers capable of differentiating between PD and DF patients, and secondly, to identify molecular networks which may contribute to the progressive tumour phenotype. The experimental design and analyses performed permitted the clear differentiation between PD and DF patients using a set of biomarkers implicated in neuroendocrine signalling and allowed the inference of a set of transcription factors whose activity may differ according to disease outcome. Potential links between the biomarkers, the transcription factors and the genes p21/CDKN1A and Myc, which have previously been implicated in NSCLC development, were revealed by a combination of pathway analysis and microarray meta-analysis. These findings suggest that neuroendocrine-related genes, potentially driven through p21/CDKN1A and Myc, are closely linked to whether or not a NSCLC patient will have poor clinical outcome.

  3. MUC1 Regulates PDGFA Expression During Pancreatic Cancer Progression

    PubMed Central

    Sahraei, Mahnaz; Roy, Lopamudra Das; Curry, Jennifer M; Teresa, Tinder L; Nath, Sritama; Besmer, Dahlia; Kidiyoor, Amritha; Dalia, Ritu; Gendler, Sandra J; Mukherjee, Pinku

    2012-01-01

    Pancreatic Ductal Adenocarcinoma (PDA) has one of the worst prognoses of all cancers. Mucin 1 (MUC1), a transmembrane mucin glycoprotein, is a key modulator of several signaling pathways that affect oncogenesis, motility, and metastasis. Its expression is known to be associated with poor prognosis in patients. However, the precise mechanism remains elusive. We report a novel association of MUC1 with Platelet-Derived Growth Factor-A (PDGFA). PDGFA is one of the many drivers of tumor growth, angiogenesis, and metastasis in PDA. Using mouse PDA models as well as human samples, we show clear evidence that MUC1 regulates the expression and secretion of PDGFA. This, in turn, influences proliferation and invasion of pancreatic cancer cells leading to higher tumor burden in vivo. In addition, we reveal that MUC1 over expressing cells are heavily dependent on PDGFA both for proliferation and invasion while MUC1-null cells are not. Moreover, PDGFA and MUC1 are critical for translocation of βcatenin to the nucleus for oncogenesis to ensue. Finally, we elucidate the underlying mechanism by which MUC1 regulates PDGFA expression and secretion in pancreatic cancer cells. We show that MUC1 associates with Hif1-α, a known transcription factor involved in controlling PDGFA expression. Furthermore, MUC1 facilitates Hif1-α translocation to the nucleus. In summary, we have demonstrated that MUC1-induced invasion and proliferation occurs via increased exogenous production of PDGFA. Thus, impeding MUC1 regulation of PDGFA signaling may be therapeutically beneficial for patients with PDA. PMID:22266848

  4. [Research progress on phosphorus budgets and regulations in reservoirs].

    PubMed

    Shen, Xiao; Li, Xu; Zhang, Wang-shou

    2014-12-01

    Phosphorus is an important limiting factor of water eutrophication. A clear understanding of its budget and regulated method is fundamental for reservoir ecological health. In order to pro- mote systematic research further and improve phosphorus regulation system, the budget balance of reservoir phosphorus and its influencing factors were concluded, as well as conventional regulation and control measures. In general, the main phosphorus sources of reservoirs include upstream input, overland runoff, industrial and domestic wastewater, aquaculture, atmospheric deposition and sediment release. Upstream input is the largest phosphorus source among them. The principal output path of phosphorus is the flood discharge, the emission load of which is mainly influenced by drainage patterns. In addition, biological harvest also can export a fraction of phosphorus. There are some factors affecting the reservoir phosphorus balance, including reservoirs' function, hydrological conditions, physical and chemical properties of water, etc. Therefore, the phosphorus budgets of different reservoirs vary greatly, according to different seasons and regions. In order to reduce the phosphorus loading in reservoirs, some methods are carried out, including constructed wetlands, prefix reservoir, sediment dredging, biomanipulation, etc. Different methods need to be chosen and combined according to different reservoirs' characteristics and water quality management goals. Thus, in the future research, it is reasonable to highlight reservoir ecological characteristics and proceed to a complete and systematic analysis of the inherent complexity of phosphorus budget and its impact factors for the reservoirs' management. Besides, the interaction between phosphorus budget and other nutrients in reservoirs also needs to be conducted. It is fundamental to reduce the reservoirs' phosphorus loading to establish a scientific and improved management system based on those researches.

  5. Implications of epigenetics and stress regulation on research and developmental care of preterm infants.

    PubMed

    Montirosso, Rosario; Provenzi, Livio

    2015-01-01

    Epigenetics refers to chemical modifications leading to changes in gene expression without any alteration of the DNA structure. We suggest ways through which epigenetic mechanisms might contribute to alter developmental trajectories in preterm infants. Although theoretical and methodological issues still need to be addressed, we discuss how epigenetics might be an emergent research field with potential innovative insights for researchers and clinicians involved in the neonatal care of preterm infants.

  6. Intragenic DNA methylation status down-regulates bovine IGF2 gene expression in different developmental stages.

    PubMed

    Huang, Yong-Zhen; Zhan, Zhao-Yang; Sun, Yu-Jia; Cao, Xiu-Kai; Li, Ming-Xun; Wang, Jing; Lan, Xian-Yong; Lei, Chu-Zhao; Zhang, Chun-Lei; Chen, Hong

    2014-01-25

    DNA methylation is a key epigenetic modification in mammals and has an essential and important role in muscle development. Insulin-like growth factor 2 (IGF2) is a fetal growth and differentiation factor that plays an important role in muscle growth and in myoblast proliferation and differentiation. The aim of this study was to evaluate the expression of IGF2 and the methylation pattern on the differentially methylated region (DMR) of the last exon of IGF2 in six tissues with two different developmental stages. The DNA methylation pattern was compared using bisulfite sequencing polymerase chain reaction (BSP) and combined bisulfite restriction analysis (COBRA). The quantitative real-time PCR (qPCR) analysis indicated that IGF2 has a broad tissue distribution and the adult bovine group showed significant lower mRNA expression levels than that in the fetal bovine group (P<0.05 or P<0.01). Moreover, the DNA methylation level analysis showed that the adult bovine group exhibited a significantly higher DNA methylation levels than that in the fetal bovine group (P<0.05 or P<0.01). These results indicate that IGF2 expression levels were negatively associated with the methylation status of the IGF2 DMR during the two developmental stages. Our results suggest that the methylation pattern in this DMR may be a useful parameter to investigate as a marker-assisted selection for muscle developmental in beef cattle breeding program and as a model for studies in other species.

  7. (Regulation of alcohol fermentation by Escherichia coli). Progress report

    SciTech Connect

    Clark, D.P.

    1985-01-01

    Constitutive adhC mutants were used as a starting point for the isolation of further mutants, some of which are defective in alcohol dehydrogenase (ADH) and/or acetaldehyde dehydrogenase (ACDH) activities and some of which are regulatory and express elevated enzyme levels. The structural mutants map close to the adhC gene, suggesting the existence of an anaerobically controlled operon responsible for the conversion of acetyl-CoA to ethanol. Purification of the two enzyme activities indicates that both copurify as a complex of approximately 200,000 daltons. Although confirmation is required, both enzyme activities appear to be functions of a single polypeptide of MW 100,000 daltons. This interpretation is consistent with genetic data which show that most mutants selected directly for loss of either enzyme have also lost the other activity. Temperature sensitive mutants in which both enzymes are thermolabile also support the idea of a single polypeptide for the two activities. Regulatory mutants located away from the adhC locus have been isolated, and result in two to tenfold elevation of both ADH and ACDH. These mutants are in process of further characterization. Study of adh regulation by means of gene fusions has been slowed by technical problems, however we have devised a direct method for the selection of mutants unable to excrete acidic fermentation products and have accumulated a variety of anaerobically regulated gene fusions which have allowed us to estimate that anaerobiosis in E. coli requires the induction of around 50 genes.

  8. A developmentally regulated membrane protein gene in Dictyostelium discoideum is also induced by heat shock and cold shock.

    PubMed Central

    Maniak, M; Nellen, W

    1988-01-01

    We have analyzed the expression of the Dictyostelium gene P8A7 which had been isolated as a cDNA clone from an early developmentally regulated gene. The single genomic copy generated two mRNAs which were subject to different control mechanisms: while one mRNA (P8A7S) was regulated like the cell-type-nonspecific late genes, the other one (P8A7L) was induced during development, when cells were allowed to attach to a substrate, and when cells were subjected to stress, such as heat shock and cadmium. Interestingly the same induction was also observed with cold shock. RNA processing was inhibited by heat and cold shock, leading to nuclear accumulation of a precursor. The translated region of the cDNA was common to both mRNAs and encoded an unusually hydrophobic peptide with the characteristics of a membrane protein. Images PMID:3336356

  9. Regulation of nucleosome positioning by a CHD Type III chromatin remodeler and its relationship to developmental gene expression in Dictyostelium

    PubMed Central

    Platt, James L.; Kent, Nicholas A.; Kimmel, Alan R.

    2017-01-01

    Nucleosome placement and repositioning can direct transcription of individual genes; however, the precise interactions of these events are complex and largely unresolved at the whole-genome level. The Chromodomain-Helicase-DNA binding (CHD) Type III proteins are a subfamily of SWI2/SNF2 proteins that control nucleosome positioning and are associated with several complex human disorders, including CHARGE syndrome and autism. Type III CHDs are required for multicellular development of animals and Dictyostelium but are absent in plants and yeast. These CHDs can mediate nucleosome translocation in vitro, but their in vivo mechanism is unknown. Here, we use genome-wide analysis of nucleosome positioning and transcription profiling to investigate the in vivo relationship between nucleosome positioning and gene expression during development of wild-type (WT) Dictyostelium and mutant cells lacking ChdC, a Type III CHD protein ortholog. We demonstrate major nucleosome positional changes associated with developmental gene regulation in WT. Loss of chdC caused an increase of intragenic nucleosome spacing and misregulation of gene expression, affecting ∼50% of the genes that are repositioned during WT development. These analyses demonstrate active nucleosome repositioning during Dictyostelium multicellular development, establish an in vivo function of CHD Type III chromatin remodeling proteins in this process, and reveal the detailed relationship between nucleosome positioning and gene regulation, as cells transition between developmental states. PMID:28330902

  10. Challenges to Developmental Regulation across the Life Course: What Are They and Which Individual Differences Matter?

    ERIC Educational Resources Information Center

    Heckhausen, Jutta; Wrosch, Carsten

    2016-01-01

    We discuss the major processes involved in individuals' motivation and self-regulation of goal striving throughout the life course. While much is regulated based on the biological and societal scaffolding of lifespan development, certain challenges for motivation and self-regulation are more substantial and need to be managed by the individual,…

  11. Parental influences on children's self-regulation of energy intake: Insights from developmental literature on emotion regulation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This article examines the role of parents in the development of children's self-regulation of energy intake. Various paths of parental influence are offered based on the literature on parental influences on children's emotion self-regulation. The parental paths include modeling, responses to childre...

  12. Smooth muscle FGF/TGFβ cross talk regulates atherosclerosis progression.

    PubMed

    Chen, Pei-Yu; Qin, Lingfeng; Li, Guangxin; Tellides, George; Simons, Michael

    2016-07-01

    The conversion of vascular smooth muscle cells (SMCs) from contractile to proliferative phenotype is thought to play an important role in atherosclerosis. However, the contribution of this process to plaque growth has never been fully defined. In this study, we show that activation of SMC TGFβ signaling, achieved by suppression of SMC fibroblast growth factor (FGF) signaling input, induces their conversion to a contractile phenotype and dramatically reduces atherosclerotic plaque size. The FGF/TGFβ signaling cross talk was observed in vitro and in vivo In vitro, inhibition of FGF signaling increased TGFβ activity, thereby promoting smooth muscle differentiation and decreasing proliferation. In vivo, smooth muscle-specific knockout of an FGF receptor adaptor Frs2α led to a profound inhibition of atherosclerotic plaque growth when these animals were crossed on Apoe(-/-) background and subjected to a high-fat diet. In particular, there was a significant reduction in plaque cellularity, increase in fibrous cap area, and decrease in necrotic core size. In agreement with these findings, examination of human coronary arteries with various degrees of atherosclerosis revealed a strong correlation between the activation of FGF signaling, loss of TGFβ activity, and increased disease severity. These results identify SMC FGF/TGFβ signaling cross talk as an important regulator of SMC phenotype switch and document a major contribution of medial SMC proliferation to atherosclerotic plaque growth.

  13. Genome-Wide Ultrabithorax Binding Analysis Reveals Highly Targeted Genomic Loci at Developmental Regulators and a Potential Connection to Polycomb-Mediated Regulation

    PubMed Central

    Meireles-Filho, Antonio C. A.; Pagani, Michaela; Stark, Alexander

    2016-01-01

    Hox homeodomain transcription factors are key regulators of animal development. They specify the identity of segments along the anterior-posterior body axis in metazoans by controlling the expression of diverse downstream targets, including transcription factors and signaling pathway components. The Drosophila melanogaster Hox factor Ultrabithorax (Ubx) directs the development of thoracic and abdominal segments and appendages, and loss of Ubx function can lead for example to the transformation of third thoracic segment appendages (e.g. halters) into second thoracic segment appendages (e.g. wings), resulting in a characteristic four-wing phenotype. Here we present a Drosophila melanogaster strain with a V5-epitope tagged Ubx allele, which we employed to obtain a high quality genome-wide map of Ubx binding sites using ChIP-seq. We confirm the sensitivity of the V5 ChIP-seq by recovering 7/8 of well-studied Ubx-dependent cis-regulatory regions. Moreover, we show that Ubx binding is predictive of enhancer activity as suggested by comparison with a genome-scale resource of in vivo tested enhancer candidates. We observed densely clustered Ubx binding sites at 12 extended genomic loci that included ANTP-C, BX-C, Polycomb complex genes, and other regulators and the clustered binding sites were frequently active enhancers. Furthermore, Ubx binding was detected at known Polycomb response elements (PREs) and was associated with significant enrichments of Pc and Pho ChIP signals in contrast to binding sites of other developmental TFs. Together, our results show that Ubx targets developmental regulators via strongly clustered binding sites and allow us to hypothesize that regulation by Ubx might involve Polycomb group proteins to maintain specific regulatory states in cooperative or mutually exclusive fashion, an attractive model that combines two groups of proteins with prominent gene regulatory roles during animal development. PMID:27575958

  14. Discovery of a Splicing Regulator Required for Cell Cycle Progression

    SciTech Connect

    Suvorova, Elena S.; Croken, Matthew; Kratzer, Stella; Ting, Li-Min; Conde de Felipe, Magnolia; Balu, Bharath; Markillie, Lye Meng; Weiss, Louis M.; Kim, Kami; White, Michael W.

    2013-02-01

    In the G1 phase of the cell division cycle, eukaryotic cells prepare many of the resources necessary for a new round of growth including renewal of the transcriptional and protein synthetic capacities and building the machinery for chromosome replication. The function of G1 has an early evolutionary origin and is preserved in single and multicellular organisms, although the regulatory mechanisms conducting G1 specific functions are only understood in a few model eukaryotes. Here we describe a new G1 mutant from an ancient family of apicomplexan protozoans. Toxoplasma gondii temperature-sensitive mutant 12-109C6 conditionally arrests in the G1 phase due to a single point mutation in a novel protein containing a single RNA-recognition-motif (TgRRM1). The resulting tyrosine to asparagine amino acid change in TgRRM1 causes severe temperature instability that generates an effective null phenotype for this protein when the mutant is shifted to the restrictive temperature. Orthologs of TgRRM1 are widely conserved in diverse eukaryote lineages, and the human counterpart (RBM42) can functionally replace the missing Toxoplasma factor. Transcriptome studies demonstrate that gene expression is downregulated in the mutant at the restrictive temperature due to a severe defect in splicing that affects both cell cycle and constitutively expressed mRNAs. The interaction of TgRRM1 with factors of the tri-SNP complex (U4/U6 & U5 snRNPs) indicate this factor may be required to assemble an active spliceosome. Thus, the TgRRM1 family of proteins is an unrecognized and evolutionarily conserved class of splicing regulators. This study demonstrates investigations into diverse unicellular eukaryotes, like the Apicomplexa, have the potential to yield new insights into important mechanisms conserved across modern eukaryotic kingdoms.

  15. Estrogen target gene regulation and coactivator expression in rat uterus after developmental exposure to the ultraviolet filter 4-methylbenzylidene camphor.

    PubMed

    Durrer, Stefan; Maerkel, Kirsten; Schlumpf, Margret; Lichtensteiger, Walter

    2005-05-01

    Because the estrogen receptor (ER) ligand type influences transactivation, it is important to obtain information on molecular actions of nonclassical ER agonists. UV filters from cosmetics represent new classes of endocrine active chemicals, including the preferential ER beta ligands 4-methylbenzylidene camphor (4-MBC) and 3-benzylidene camphor. We studied estrogen target gene expression in uterus of Long Evans rats after developmental exposure to 4-MBC (0.7, 7, 24, and 47 mg/kg x d) administered in feed to the parent generation before mating, during pregnancy and lactation, and to the offspring until adulthood. 4-MBC altered steady-state levels of mRNAs encoding for ER alpha, ER beta, progesterone receptor (PR), IGF-I, androgen receptor, determined by real-time RT-PCR in uterus of 12-wk-old offspring. Western-blot analyses of the same tissue homogenates indicated changes in ER alpha and PR but not ER beta proteins. To assess sensitivity to estradiol (E2), offspring were ovariectomized on d 70, injected with E2 (10 or 50 microg/kg sc) on d 84, and killed 6 h later. Acute up-regulation of PR and IGF-I and down-regulation of ER alpha and androgen receptor by E2 were dose-dependently reduced in 4-MBC-exposed rats. The reduced response to E2 was accompanied by reduced coactivator SRC-1 mRNA and protein levels. Our data indicate that developmental exposure to 4-MBC affects the regulation of estrogen target genes and the expression of nuclear receptor coregulators in uterus at mRNA and protein levels.

  16. miR-17 and miR-20a temper an E2F1-induced G1 checkpoint to regulate cell cycle progression.

    PubMed

    Pickering, M T; Stadler, B M; Kowalik, T F

    2009-01-08

    The stringent regulation of cell cycle progression helps to maintain genetic stability in cells. MicroRNAs (miRNAs) are critical regulators of gene expression in diverse cellular pathways, including developmental patterning, hematopoietic differentiation and antiviral defense. Here, we show that two c-Myc-regulated miRNAs, miR-17 and miR-20a, govern the transition through G1 in normal diploid human cells. Inhibition of these miRNAs leads to a G1 checkpoint due to an accumulation of DNA double-strand breaks, resulting from premature temporal accumulation of the E2F1 transcription factor. Surprisingly, gross changes in E2F1 levels were not required to initiate the DNA damage response and checkpoint, as these responses could occur with a less than twofold change in E2F1 protein levels. Instead, our findings indicate that the precise timing of E2F1 expression dictates S-phase entry and that accurate timing of E2F1 accumulation requires converging signals from the Rb/E2F pathway and the c-Myc-regulated miR-17 and miR-20a miRNAs to circumvent a G1 checkpoint arising from the untimely accumulation of E2F1. These data provide a mechanistic view of miRNA-based regulation of E2F1 in the context of the emerging model that miRNAs coordinate the timing of cell cycle progression.

  17. Root gravitropism and root hair development constitute coupled developmental responses regulated by auxin homeostasis in the Arabidopsis root apex.

    PubMed

    Rigas, Stamatis; Ditengou, Franck Anicet; Ljung, Karin; Daras, Gerasimos; Tietz, Olaf; Palme, Klaus; Hatzopoulos, Polydefkis

    2013-03-01

    Active polar transport establishes directional auxin flow and the generation of local auxin gradients implicated in plant responses and development. Auxin modulates gravitropism at the root tip and root hair morphogenesis at the differentiation zone. Genetic and biochemical analyses provide evidence for defective basipetal auxin transport in trh1 roots. The trh1, pin2, axr2 and aux1 mutants, and transgenic plants overexpressing PIN1, all showing impaired gravity response and root hair development, revealed ectopic PIN1 localization. The auxin antagonist hypaphorine blocked root hair elongation and caused moderate agravitropic root growth, also leading to PIN1 mislocalization. These results suggest that auxin imbalance leads to proximal and distal developmental defects in Arabidopsis root apex, associated with agravitropic root growth and root hair phenotype, respectively, providing evidence that these two auxin-regulated processes are coupled. Cell-specific subcellular localization of TRH1-YFP in stele and epidermis supports TRH1 engagement in auxin transport, and hence impaired function in trh1 causes dual defects of auxin imbalance. The interplay between intrinsic cues determining root epidermal cell fate through the TTG/GL2 pathway and environmental cues including abiotic stresses modulates root hair morphogenesis. As a consequence of auxin imbalance in Arabidopsis root apex, ectopic PIN1 mislocalization could be a risk aversion mechanism to trigger root developmental responses ensuring root growth plasticity.

  18. Developmentally regulated enzymes and cyclic AMP-binding sites in Dictyostelium discoideum cells blocked during development by alpha-chymotrypsin.

    PubMed Central

    Schmidt, J A; Stirling, J L

    1982-01-01

    When cells of the slime mould Dictyostelium discoideum are allowed to starve in the presence of alpha-chymotrypsin, they are blocked in development at the stage where tight aggregates form tips. Analysis of developmentally regulated enzymes has shown that alpha-mannosidase, beta-N-acetylglucosaminidase, threonine deaminase, tyrosine aminotransferase, beta-glucosidase and the carbohydrate-binding protein discoidin are unaffected, but enzymes that show an increase in specific activity during post-aggregative development, namely glycogen phosphorylase, UDP-glucose pyrophosphorylase, UDP-galactose 4-epimerase, UDP-galactose polysaccharide transferase and alkaline phosphatase, did not show the characteristic increase when development was blocked by alpha-chymotrypsin. Recovery of cells from the effects of alpha-chymotrypsin was accompanied by the formation of fruiting bodies and a concomitant increase in the specific activity of UDP-glucose pyrophosphorylase. Uptake or efflux of 45Ca2+ was not altered in the presence of alpha-chymotrypsin. Cells allowed to develop in alpha-chymotrypsin, or treated with the enzyme for 15 min, had a markedly reduced ability to bind cyclic AMP with low affinity; high-affinity binding was unaffected. Pronase had a similar effect on cyclic AMP binding, but trypsin, which does not alter developmental processes, has no effect on cyclic AMP binding to D. discoideum cells. PMID:7150239

  19. MicroRNAs in Breastmilk and the Lactating Breast: Potential Immunoprotectors and Developmental Regulators for the Infant and the Mother

    PubMed Central

    Alsaweed, Mohammed; Hartmann, Peter E.; Geddes, Donna T.; Kakulas, Foteini

    2015-01-01

    Human milk (HM) is the optimal source of nutrition, protection and developmental programming for infants. It is species-specific and consists of various bioactive components, including microRNAs, small non-coding RNAs regulating gene expression at the post-transcriptional level. microRNAs are both intra- and extra-cellular and are present in body fluids of humans and animals. Of these body fluids, HM appears to be one of the richest sources of microRNA, which are highly conserved in its different fractions, with milk cells containing more microRNAs than milk lipids, followed by skim milk. Potential effects of exogenous food-derived microRNAs on gene expression have been demonstrated, together with the stability of milk-derived microRNAs in the gastrointestinal tract. Taken together, these strongly support the notion that milk microRNAs enter the systemic circulation of the HM fed infant and exert tissue-specific immunoprotective and developmental functions. This has initiated intensive research on the origin, fate and functional significance of milk microRNAs. Importantly, recent studies have provided evidence of endogenous synthesis of HM microRNA within the human lactating mammary epithelium. These findings will now form the basis for investigations of the role of microRNA in the epigenetic control of normal and aberrant mammary development, and particularly lactation performance. PMID:26529003

  20. Developmental effects on ureide levels are mediated by tissue-specific regulation of allantoinase in Phaseolus vulgaris L.

    PubMed

    Díaz-Leal, Juan Luis; Gálvez-Valdivieso, Gregorio; Fernández, Javier; Pineda, Manuel; Alamillo, Josefa M

    2012-06-01

    The ureides allantoin and allantoate are key molecules in the transport and storage of nitrogen in ureide legumes. In shoots and leaves from Phaseolus vulgaris plants using symbiotically fixed nitrogen as the sole nitrogen source, ureide levels were roughly equivalent to those of nitrate-supported plants during the whole vegetative stage, but they exhibited a sudden increase at the onset of flowering. This rise in the level of ureides, mainly in the form of allantoate, was accompanied by increases in allantoinase gene expression and enzyme activity, consistent with developmental regulation of ureide levels mainly through the tissue-specific induction of allantoate synthesis catalysed by allantoinase. Moreover, surprisingly high levels of ureides were also found in non-nodulated plants fertilized with nitrate, at both early and late developmental stages. The results suggest that remobilized N from lower leaves is probably involved in the sharp rise in ureides in shoots and leaves during early pod filling in N(2)-fixing plants and in the significant amounts of ureides observed in non-nodulated plants.

  1. Multiple developmental roles for CRAC, a cytosolic regulator of adenylyl cyclase.

    PubMed

    Wang, B; Shaulsky, G; Kuspa, A

    1999-04-01

    Receptor-mediated activation of adenylyl cyclase (ACA) in Dictyostelium requires CRAC protein. Upon translocation to the membrane, this pleckstrin homology (PH) domain protein stimulates ACA and thereby mediates developmental aggregation. CRAC may also have roles later in development since CRAC-null cells can respond to chemotactic signals and participate in developmental aggregation when admixed with wild-type cells, but they do not complete development within such chimeras. To test whether the role of CRAC in postaggregative development is related to the activation of ACA, chemotactic aggregation was bypassed in CRAC-null cells by activating the cAMP-dependent protein kinase (PKA). While such strains formed mounds, they did not complete fruiting body morphogenesis or form spores. Expression of CRAC in the prespore cells of these strains rescued sporulation and fruiting body formation. This later function of CRAC does not appear to require its PH domain since the C-terminal portion of the protein (CRAC-DeltaPH) can substitute for full-length CRAC in promoting spore cell formation and morphogenesis. No detectable ACA activation was observed in any of the CRAC-null strains rescued by PKA activation and expression of CRAC-DeltaPH. Finally, we found that the development of CRAC-null ACA-null double mutants could be rescued by the activation of PKA together with the expression of CRAC-DeltaPH. Thus, there appears to be a required function for CRAC in postaggregative development that is independent of its previously described function in the ACA activation pathway.

  2. Developmental programming of energy balance regulation: Is physical activity more "programmable" than food intake

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Extensive human and animal model data show that environmental influences during critical periods of prenatal and early postnatal development can cause persistent alterations in energy balance regulation. Although a potentially important factor in the worldwide obesity epidemic, the fundamental mecha...

  3. Identifying Developmental Cascades among Differentiated Dimensions of Social Competence and Emotion Regulation

    PubMed Central

    Blair, Bethany L.; Perry, Nicole B.; O'Brien, Marion; Calkins, Susan D.; Keane, Susan P.; Shanahan, Lilly

    2015-01-01

    This study utilized data from 356 children, their mothers, teachers, and peers, to examine the longitudinal and dynamic associations among three dimensions of social competence derived from Hinde's (1987) framework of social complexity: social skills, peer group acceptance, and friendship quality. Direct and indirect associations among each discrete dimension of social competence and emotion regulation were also examined. Results suggest that there are important distinctions among the dimensions of social competence as they relate to one another and to emotion regulation. Model comparisons provided evidence of cascade and reciprocal effects among the variables, demonstrating complex associations that are ongoing across middle childhood. Specifically, there were cascading effects from emotion regulation abilities at age 5 to social skills at age 7, which was then associated with age 10 outcomes of more positive friendship quality, greater peer acceptance, and greater emotion regulation. PMID:26147773

  4. Cardiovascular regulation profile predicts developmental trajectory of BMI and pediatric obesity.

    PubMed

    Graziano, Paulo A; Calkins, Susan D; Keane, Susan P; O'Brien, Marion

    2011-09-01

    The present study examined the role of cardiovascular regulation in predicting pediatric obesity. Participants for this study included 268 children (141 girls) obtained from a larger ongoing longitudinal study. To assess cardiac vagal regulation, resting measures of respiratory sinus arrhythmia (RSA) and RSA change (vagal withdrawal) to three cognitively challenging tasks were derived when children were 5.5 years of age. Heart period (HP) and HP change (heart rate (HR) acceleration) were also examined. Height and weight measures were collected when children were 5.5, 7.5, and 10.5 years of age. Results indicated that physiological regulation at age 5.5 was predictive of both normal variations in BMI development and pediatric obesity at age 10.5. Specifically, children with a cardiovascular regulation profile characterized by lower levels of RSA suppression and HP change experienced significantly greater levels of BMI growth and were more likely to be classified as overweight/at-risk for overweight at age 10.5 compared to children with a cardiovascular regulation profile characterized by high levels of RSA suppression and HP change. However, a significant interaction with racial status was found suggesting that the association between cardiovascular regulation profile and BMI growth and pediatric obesity was only significant for African-American children. An autonomic cardiovascular regulation profile consisting of low parasympathetic activity represents a significant individual risk factor for the development of pediatric obesity, but only for African-American children. Mechanisms by which early physiological regulation difficulties may contribute to the development of pediatric obesity are discussed.

  5. [Regulation of terpene metabolism]. Annual progress report, March 15, 1988--March 14, 1989

    SciTech Connect

    Croteau, R.

    1989-12-31

    Progress in understanding of the metabolism of monoterpenes by peppermint and spearmint is recorded including the actions of two key enzymes, geranyl pyrophosphate:limonene cyclase and a UDP-glucose dependent glucosyl transferase; concerning the ultrastructure of oil gland senescence; enzyme subcellular localization; regulation of metabolism; and tissue culture systems.

  6. Dissecting dysfunctional crosstalk pathways regulated by miRNAs during glioma progression

    PubMed Central

    Li, Feng; Li, Xiang; Feng, Li; Shi, Xinrui; Wang, Lihua; Li, Xia

    2016-01-01

    Glioma is a malignant nervous system tumor with a high fatality rate and poor prognosis. MicroRNAs (miRNAs) are important post-transcriptional modulators of glioma initiation and progression. Tumor progression often results from dysfunctional co-operation between pathways regulated by miRNAs. We therefore constructed a glioma progression-related miRNA-pathway crosstalk network that not only revealed some key miRNA-pathway patterns, but also helped characterize the functional roles of miRNAs during glioma progression. Our data indicate that crosstalk between cell cycle and p53 pathways is associated with grade II to grade III progression, while cell communications-related pathways involving regulation of actin cytoskeleton and adherens junctions are associated with grade IV glioblastoma progression. Furthermore, miRNAs and their crosstalk pathways may be useful for stratifying glioma and glioblastoma patients into groups with short or long survival times. Our data indicate that a combination of miRNA and pathway crosstalk information can be used for survival prediction. PMID:27013589

  7. Cold adaptation overrides developmental regulation of sarcolipin expression in mice skeletal muscle: SOS for muscle-based thermogenesis?

    PubMed

    Pant, Meghna; Bal, Naresh C; Periasamy, Muthu

    2015-08-01

    Neonatal mice have a greater thermogenic need than adult mice and may require additional means of heat production, other than the established mechanism of brown adipose tissue (BAT). We and others recently discovered a novel mediator of skeletal muscle-based thermogenesis called sarcolipin (SLN) that acts by uncoupling sarcoendoplasmic reticulum Ca(2+)-ATPase (SERCA). In addition, we have shown that SLN expression is downregulated during neonatal development in rats. In this study we probed two questions: (1) is SLN expression developmentally regulated in neonatal mice?; and (2) if so, will cold adaptation override this? Our data show that SLN expression is higher during early neonatal stages and is gradually downregulated in fast twitch skeletal muscles. Interestingly, we demonstrate that cold acclimation of neonatal mice can prevent downregulation of SLN expression. This observation suggests that SLN-mediated thermogenesis can be recruited to a greater extent during extreme physiological need, in addition to BAT.

  8. The developmentally regulated expression of Menkes protein ATP7A suggests a role in axon extension and synaptogenesis.

    PubMed

    El Meskini, Rajaâ; Cline, Laura B; Eipper, Betty A; Ronnett, Gabriele V

    2005-01-01

    Menkes disease (MD) is a neurodegenerative disorder caused by mutation of the copper transporter ATP7A. While several enzymes expressed in mature neurons require copper, MD neurodegenerative changes cannot be explained by known requirements for ATP7A in neuronal development. To investigate additional roles for ATP7A during development, we characterized its pattern of expression using the olfactory system as a neurodevelopmental model. ATP7A expression in neurons was developmentally regulated rather than constitutively. Initially expressed in the cell bodies of developing neurons, ATP7A protein later shifted to extending axons, peaking prior to synaptogenesis. Similarly, after injury-stimulated neurogenesis, ATP7A expression increased in neurons and axons preceding synaptogenesis. Interestingly, copper-transport-deficient ATP7A still exhibits axonal localization. These results support a role for ATP7A in axon extension, which may contribute to the severe neurodegeneration characteristic of MD.

  9. Expression Profiling Reveals Developmentally Regulated lncRNA Repertoire in the Mouse Male Germline1

    PubMed Central

    Bao, Jianqiang; Wu, Jingwen; Schuster, Andrew S.; Hennig, Grant W.; Yan, Wei

    2013-01-01

    ABSTRACT In mammals, the transcriptome of large noncoding RNAs (lncRNAs) is believed to be greater than that of messenger RNAs (mRNAs). Some lncRNAs, especially large intergenic noncoding RNAs (lincRNAs), participate in epigenetic regulation by binding chromatin-modifying protein complexes and regulating protein-coding gene expression. Given that epigenetic regulation plays a critical role in male germline development, we embarked on expression profiling of both lncRNAs and mRNAs during male germline reprogramming and postnatal development using microarray analyses. We identified thousands of lncRNAs and hundreds of lincRNAs that are either up- or downregulated at six critical time points during male germ cell development. In addition, highly regulated lncRNAs were correlated with nearby (<30 kb) mRNA gene clusters, which were also significantly up- or downregulated. Large ncRNAs can be localized to both the nucleus and cytoplasm, with nuclear lncRNAs mostly associated with key components of the chromatin-remodeling protein complexes. Our data indicate that expression of lncRNAs is dynamically regulated during male germline development and that lncRNAs may function to regulate gene expression at both transcriptional and posttranscriptional levels via genetic and epigenetic mechanisms. PMID:24048575

  10. Coordinated regulation of genes for secretion in tobacco at late developmental stages: association with resistance against oomycetes.

    PubMed

    Hugot, Karine; Rivière, Marie-Pierre; Moreilhon, Chimène; Dayem, Manal A; Cozzitorto, Joseph; Arbiol, Gilles; Barbry, Pascal; Weiss, Catherine; Galiana, Eric

    2004-02-01

    Besides the systemic acquired resistance (SAR) induced in response to microbial stimulation, host plants may also acquire resistance to pathogens in response to endogenous stimuli associated with their own development. In tobacco (Nicotiana tabacum), the vegetative-to-flowering transition comes along with a susceptibility-to-resistance transition to the causal agent of black shank disease, the oomycete Phytophthora parasitica. This resistance affects infection effectiveness and hyphal expansion and is associated with extracellular accumulation of a cytotoxic activity that provokes in vitro cell death of P. parasitica zoospores. As a strategy to determine the extracellular events important for restriction of pathogen growth, we screened the tobacco genome for genes encoding secreted or membrane-bound proteins expressed in leaves of flowering plants. Using a signal sequence trap approach in yeast (Saccharomyces cerevisiae), 298 clones were selected that appear to encode for apoplastic, cell wall, or membrane-bound proteins involved in stress response, in plant defense, or in cell wall modifications. Microarray and northern-blot analyses revealed that, at late developmental stages, leaves were characterized by the coordinate up-regulation of genes involved in SAR and in peroxidative cross-linking of structural proteins to cell wall. This suggests the potential involvement of these genes in extracellular events that govern the expression of developmental resistance. The analysis of the influence of salicylic acid on mRNA accumulation also indicates a more complex network for regulation of gene expression at a later stage of tobacco development than during SAR. Further characterization of these genes will permit the formulation of hypotheses to explain resistance and to establish the connection with development.

  11. Developmental regulation of neuraminidase-sensitive lectin-binding glycoproteins during myogenesis of rat L6 myoblasts.

    PubMed Central

    Holland, P C; Pena, S D; Guerin, C W

    1984-01-01

    Intact monolayers of L6 myoblasts were treated with neuraminidase, with the aim of selectively removing sialic acid residues of cell-surface glycoproteins. Neuraminidase treatment unmasked binding sites for Ricinus communis agglutinin I and peanut agglutinin, thus allowing the identification of the major binding proteins for these lectins. For Ricinus communis agglutinin I these neuraminidase-sensitive glycoproteins had apparent Mr values of 136000, 115000, 87000, 83000 and 49000. For peanut agglutinin the major neuraminidase-sensitive glycoproteins had apparent Mr values of 200000, 136000, 87000 and 83000. We found highly reproducible, developmentally regulated, changes in the lectin-binding capacity of certain of these glycoproteins as L6 myoblasts differentiated into myotubes. Coincident with myoblast fusion there was a co-ordinate decrease in Ricinus communis agglutinin I binding by glycoproteins of apparent Mr of 136000 and 49000. There was also a co-ordinate shift in mobility of the broad band of glycoprotein, centred at an apparent Mr of 115000 in myoblasts, to a new average apparent Mr of 107000 in mid-fusion cultures and myotube cultures. Peanut agglutinin binding by the major protein of apparent Mr 136000 also decreased at the mid-fusion stage of myogenesis, and was barely detectable in 7-day-old fused cultures. These developmentally regulated changes in neuraminidase-sensitive glycoproteins were all inhibited by growth of myoblasts in 6.4 microM-5-bromo-2'-deoxyuridine, indicating that they are associated with myoblast differentiation. In contrast, an increase in fibronectin was seen in mid-fusion cultures, which was not inhibited by growth of myoblasts in 5-bromo-2'-deoxyuridine. This initial increase in fibronectin is, therefore, unlikely to be directly related to myoblast fusion or differentiation. Images Fig. 1. Fig. 2. Fig. 3. Fig. 4. Fig. 5. Fig. 6. PMID:6712625

  12. The mouse Crx 5'-upstream transgene sequence directs cell-specific and developmentally regulated expression in retinal photoreceptor cells.

    PubMed

    Furukawa, Akiko; Koike, Chieko; Lippincott, Pia; Cepko, Constance L; Furukawa, Takahisa

    2002-03-01

    Crx, an Otx-like homeobox gene, is expressed primarily in the photoreceptors of the retina and in the pinealocytes of the pineal gland. The CRX homeodomain protein is a transactivator of many photoreceptor/pineal-specific genes in vivo, such as rhodopsin and the cone opsins. Mutations in Crx are associated with the retinal diseases, cone-rod dystrophy-2, retinitis pigmentosa, and Leber's congenital amaurosis, which lead to loss of vision. We have generated transgenic mice, using 5'- and/or 3'-flanking sequences from the mouse Crx homeobox gene fused to the beta-galactosidase (lacZ) reporter gene, and we have investigated the promoter function of the cell-specific and developmentally regulated expression of Crx. All of the independent transgenic lines commonly showed lacZ expression in the photoreceptor cells of the retina and in the pinealocytes of the pineal gland. We characterized the transgenic lines in detail for cell-specific lacZ expression patterns by 5-bromo-4-chloro-3-indolyl beta-D-galactoside staining and lacZ immunostaining. The lacZ expression was observed in developing and developed photoreceptor cells. This observation was confirmed by coimmunostaining of dissociated retinal cells with the lacZ and opsin antibodies. The ontogeny analysis indicated that the lacZ expression completely agrees with a temporal expression pattern of Crx during retinal development. This study demonstrates that the mouse Crx 5'-upstream genomic sequence is capable of directing a cell-specific and developmentally regulated expression of Crx in photoreceptor cells.

  13. Developmental time rather than local environment regulates the schedule of epithelial polarization in the zebrafish neural rod

    PubMed Central

    2013-01-01

    Background Morphogenesis requires developmental processes to occur both at the right time and in the right place. During neural tube formation in the zebrafish embryo, the generation of the apical specializations of the lumen must occur in the center of the neural rod after the neural cells have undergone convergence, invagination and interdigitation across the midline. How this coordination is achieved is uncertain. One possibility is that environmental signaling at the midline of the neural rod controls the schedule of apical polarization. Alternatively, polarization could be regulated by a timing mechanism and then independent morphogenetic processes ensure the cells are in the correct spatial location. Results Ectopic transplantation demonstrates the local environment of the neural midline is not required for neural cell polarization. Neural cells can self-organize into epithelial cysts in ectopic locations in the embryo and also in three-dimensional gel cultures. Heterochronic transplants demonstrate that the schedule of polarization and the specialized cell divisions characteristic of the neural rod are more strongly regulated by time than local environmental signals. The cells’ schedule for polarization is set prior to gastrulation, is stable through several rounds of cell division and appears independent of the morphogenetic movements of gastrulation and neurulation. Conclusions Time rather than local environment regulates the schedule of epithelial polarization in zebrafish neural rod. PMID:23521850

  14. Machine learning classification of cell-specific cardiac enhancers uncovers developmental subnetworks regulating progenitor cell division and cell fate specification.

    PubMed

    Ahmad, Shaad M; Busser, Brian W; Huang, Di; Cozart, Elizabeth J; Michaud, Sébastien; Zhu, Xianmin; Jeffries, Neal; Aboukhalil, Anton; Bulyk, Martha L; Ovcharenko, Ivan; Michelson, Alan M

    2014-02-01

    The Drosophila heart is composed of two distinct cell types, the contractile cardial cells (CCs) and the surrounding non-muscle pericardial cells (PCs), development of which is regulated by a network of conserved signaling molecules and transcription factors (TFs). Here, we used machine learning with array-based chromatin immunoprecipitation (ChIP) data and TF sequence motifs to computationally classify cell type-specific cardiac enhancers. Extensive testing of predicted enhancers at single-cell resolution revealed the added value of ChIP data for modeling cell type-specific activities. Furthermore, clustering the top-scoring classifier sequence features identified novel cardiac and cell type-specific regulatory motifs. For example, we found that the Myb motif learned by the classifier is crucial for CC activity, and the Myb TF acts in concert with two forkhead domain TFs and Polo kinase to regulate cardiac progenitor cell divisions. In addition, differential motif enrichment and cis-trans genetic studies revealed that the Notch signaling pathway TF Suppressor of Hairless [Su(H)] discriminates PC from CC enhancer activities. Collectively, these studies elucidate molecular pathways used in the regulatory decisions for proliferation and differentiation of cardiac progenitor cells, implicate Su(H) in regulating cell fate decisions of these progenitors, and document the utility of enhancer modeling in uncovering developmental regulatory subnetworks.

  15. Machine learning classification of cell-specific cardiac enhancers uncovers developmental subnetworks regulating progenitor cell division and cell fate specification

    PubMed Central

    Ahmad, Shaad M.; Busser, Brian W.; Huang, Di; Cozart, Elizabeth J.; Michaud, Sébastien; Zhu, Xianmin; Jeffries, Neal; Aboukhalil, Anton; Bulyk, Martha L.; Ovcharenko, Ivan; Michelson, Alan M.

    2014-01-01

    The Drosophila heart is composed of two distinct cell types, the contractile cardial cells (CCs) and the surrounding non-muscle pericardial cells (PCs), development of which is regulated by a network of conserved signaling molecules and transcription factors (TFs). Here, we used machine learning with array-based chromatin immunoprecipitation (ChIP) data and TF sequence motifs to computationally classify cell type-specific cardiac enhancers. Extensive testing of predicted enhancers at single-cell resolution revealed the added value of ChIP data for modeling cell type-specific activities. Furthermore, clustering the top-scoring classifier sequence features identified novel cardiac and cell type-specific regulatory motifs. For example, we found that the Myb motif learned by the classifier is crucial for CC activity, and the Myb TF acts in concert with two forkhead domain TFs and Polo kinase to regulate cardiac progenitor cell divisions. In addition, differential motif enrichment and cis-trans genetic studies revealed that the Notch signaling pathway TF Suppressor of Hairless [Su(H)] discriminates PC from CC enhancer activities. Collectively, these studies elucidate molecular pathways used in the regulatory decisions for proliferation and differentiation of cardiac progenitor cells, implicate Su(H) in regulating cell fate decisions of these progenitors, and document the utility of enhancer modeling in uncovering developmental regulatory subnetworks. PMID:24496624

  16. Histone acetyltransferase AtGCN5/HAG1 is a versatile regulator of developmental and inducible gene expression in Arabidopsis.

    PubMed

    Servet, Caroline; Conde e Silva, Natalia; Zhou, Dao-Xiu

    2010-07-01

    Histone acetylation/deacetylation is a dynamic process and plays an important role in gene regulation. Histone acetylation homeostasis is regulated by antagonist actions of histone acetyltransferases (HAT) and deacetylases (HDAC). Plant genome encodes multiple HATs and HDACs. The Arabidopsis HAT gene AtGCN5/HAG1plays an essential role in many plant development processes, such as meristem function, cell differentiation, leaf and floral organogenesis, and responses to environmental conditions such as light and cold, indicating an important role of this HAT in the regulation of both long-term developmental switches and short-term inducible gene expression. AtGCN5 targets to a large number of promoters and is required for acetylation of several histone H3 lysine residues. Recruitment of AtGCN5 to target promoters is likely to be mediated by direct or indirect interaction with DNA-binding transcription factors and/or by interaction with acetylated histone lysine residues on the targets. Interplay between AtGCN5 and other HAT and HDAC is demonstrated to control specific regulatory pathways. Analysis of the role of AtGCN5 in light-inducible gene expression suggests a function of AtGCN5 in preparing chromatin commitment for priming inducible gene activation in plants.

  17. Chronic up-regulation of the SHH pathway normalizes some developmental effects of trisomy in Ts65Dn mice

    PubMed Central

    Dutka, Tara; Hallberg, Dorothy; Reeves, Roger H.

    2014-01-01

    Down Syndrome (DS) is a highly complex developmental genetic disorder caused by trisomy for human chromosome 21 (Hsa21). All individuals with DS exhibit some degree of brain structural changes and cognitive impairment; mouse models such as Ts65Dn have been instrumental in understanding the underlying mechanisms. Several phenotypes of DS might arise from a reduced response of trisomic cells to the Sonic Hedgehog (SHH) growth factor. If all trisomic cells show a similar reduced response to SHH, then up-regulation of the pathway in trisomic cells might ameliorate multiple DS phenotypes. We crossed Ptch1tm1Mps/+ mice, in which the canonical SHH pathway is expected to be up-regulated in every SHH-responsive cell due to the loss of function of one allele of the pathway suppressor, Ptch1, to the Ts65Dn DS model and assessed the progeny for possible rescue of multiple DS-related phenotypes. Down-regulation of Ptch produced several previously unreported effects on development by itself, complicating interpretation of some phenotypes, and a number structural or behavioral effects of trisomy were not compensated by SHH signaling. However, a deficit in a nest-building task was partially restored in Ts;Ptch+/− mice, as were structural anomalies of the cerebellum in Ts65Dn mice. These results extend the body of evidence indicating that reduced response to SHH in trisomic cells and tissues contributes to various aspects of the trisomic phenotype. PMID:25511459

  18. Molecular cloning and characterization of CFT1, a developmentally regulated avian alpha(1,3)-fucosyltransferase gene.

    PubMed

    Lee, K P; Carlson, L M; Woodcock, J B; Ramachandra, N; Schultz, T L; Davis, T A; Lowe, J B; Thompson, C B; Larsen, R D

    1996-12-20

    Although coordinate expression of carbohydrate epitopes during development is well described, mechanisms which regulate this expression remain largely unknown. In this study we demonstrate that developing chicken B cells express the LewisX terminal oligosaccharide structure in a stage-specific manner. To examine regulation of this expression, we have cloned and expressed the chicken alpha(1,3)-fucosyltransferase gene involved in LewisX biosynthesis, naming it chicken fucosyltransferase 1 (CFT1). CFT1 is characterized by a single long open reading frame of 356 amino acids encoding a type II transmembrane glycoprotein. The domain structure and predicted amino acid sequence are highly conserved between CFT1 and mammalian FucTIV genes (52.8% and 46.3% identity to mouse and human respectively). In vitro CFT1 fucosyltransferase activity utilizes LacNAc > 3'sialyl-LacNAc acceptors with almost no utilization of other neutral type II (lactose, 2-fucosyllactose), or type I (lacto-N-biose I) acceptors. CFT1-transfected cells make cell surface LewisX (COS-7) and LewisX + VIM-2 structures (Chinese hamster ovary). CFT1 gene expression is tissue-specific and includes embryonic thymus and bursa. Furthermore, expression of the CFT1 gene and cell surface LewisX structures are closely linked during B cell development. These findings reveal the evolutionary conservation between nonmammalian and mammalian alpha(1,3)-fucosyltransferase genes and demonstrate a role for fucosyltransferase gene regulation in the developmental expression of oligosaccharide structures.

  19. Cytosolic phospholipase A2α regulates G1 progression through modulating FOXO1 activity

    PubMed Central

    Naini, Said Movahedi; Choukroun, Gabriel J.; Ryan, James R.; Hentschel, Dirk M.; Shah, Jagesh V.; Bonventre, Joseph V.

    2016-01-01

    Group IVA phospholipase A2 [cytosolic phospholipase A2α (cPLA2α)] is a key mediator of inflammation and tumorigenesis. In this study, by using a combination of chemical inhibition and genetic approaches in zebrafish and murine cells, we identify a mechanism by which cPLA2α promotes cell proliferation. We identified 2 cpla2α genes in zebrafish, cpla2αa and cpla2αb, with conserved phospholipase activity. In zebrafish, loss of cpla2α expression or inhibition of cpla2α activity diminished G1 progression through the cell cycle. This phenotype was also seen in both mouse embryonic fibroblasts and mesangial cells. G1 progression was rescued by the addition of arachidonic acid or prostaglandin E2 (PGE2), indicating a phospholipase-dependent mechanism. We further show that PGE2, through PI3K/AKT activation, promoted Forkhead box protein O1 (FOXO1) phosphorylation and FOXO1 nuclear export. This led to up-regulation of cyclin D1 and down-regulation of p27Kip1, thus promoting G1 progression. Finally, using pharmacologic inhibitors, we show that cPLA2α, rapidly accelerated fibrosarcoma (RAF)/MEK/ERK, and PI3K/AKT signaling pathways cooperatively regulate G1 progression in response to platelet-derived growth factor stimulation. In summary, these data indicate that cPLA2α, through its phospholipase activity, is a critical effector of G1 phase progression through the cell cycle and suggest that pharmacological targeting of this enzyme may have important therapeutic benefits in disease mechanisms that involve excessive cell proliferation, in particular, cancer and proliferative glomerulopathies.—Naini, S. M., Choukroun, G. J., Ryan, J. R., Hentschel, D. M., Shah, J. V., Bonventre, J. V. Cytosolic phospholipase A2α regulates G1 progression through modulating FOXO1 activity. PMID:26644349

  20. Erbb2 up-regulation of ADAM12 expression accelerates skin cancer progression.

    PubMed

    Rao, Velidi H; Vogel, Kristen; Yanagida, Jodi K; Marwaha, Nitin; Kandel, Amrit; Trempus, Carol; Repertinger, Susan K; Hansen, Laura A

    2015-10-01

    Solar ultraviolet (UV) radiation can cause severe damage to the skin and is the primary cause of most skin cancer. UV radiation causes DNA damage leading to mutations and also activates the Erbb2/HER2 receptor through indirect mechanisms involving reactive oxygen species. We hypothesized that Erbb2 activation accelerates the malignant progression of UV-induced skin cancer. Following the induction of benign squamous papillomas by UV exposure of v-ras(Ha) transgenic Tg.AC mice, mice were treated topically with the Erbb2 inhibitor AG825 and tumor progression monitored. AG825 treatment reduced tumor volume, increased tumor regression, and delayed the development of malignant squamous cell carcinoma (SCC). Progression to malignancy was associated with increased Erbb2 and ADAM12 (A Disintegin And Metalloproteinase 12) transcripts and protein, while inhibition of Erbb2 blocked the increase in ADAM12 message upon malignant progression. Similarly, human SCC and SCC cell lines had increased ADAM12 protein and transcripts when compared to normal controls. To determine whether Erbb2 up-regulation of ADAM12 contributed to malignant progression of skin cancer, Erbb2 expression was modulated in cultured SCC cells using forced over-expression or siRNA targeting, demonstrating up-regulation of ADAM12 by Erbb2. Furthermore, ADAM12 transfection or siRNA targeting revealed that ADAM12 increased both the migration and invasion of cutaneous SCC cells. Collectively, these results suggest Erbb2 up-regulation of ADAM12 as a novel mechanism contributing to the malignant progression of UV-induced skin cancer. Inhibition of Erbb2/HER2 reduced tumor burden, increased tumor regression, and delayed the progression of benign skin tumors to malignant SCC in UV-exposed mice. Inhibition of Erbb2 suppressed the increase in metalloproteinase ADAM12 expression in skin tumors, which in turn increased migration and tumor cell invasiveness.

  1. Regulation of Life Cycle Checkpoints and Developmental Activation of Infective Larvae in Strongyloides stercoralis by Dafachronic Acid

    PubMed Central

    Pilgrim, Adeiye A.; Nolan, Thomas J.; Wang, Zhu; Kliewer, Steven A.; Mangelsdorf, David J.; Lok, James B.

    2016-01-01

    The complex life cycle of the parasitic nematode Strongyloides stercoralis leads to either developmental arrest of infectious third-stage larvae (iL3) or growth to reproductive adults. In the free-living nematode Caenorhabditis elegans, analogous determination between dauer arrest and reproductive growth is governed by dafachronic acids (DAs), a class of steroid hormones that are ligands for the nuclear hormone receptor DAF-12. Biosynthesis of DAs requires the cytochrome P450 (CYP) DAF-9. We tested the hypothesis that DAs also regulate S. stercoralis development via DAF-12 signaling at three points. First, we found that 1 μM Δ7-DA stimulated 100% of post-parasitic first-stage larvae (L1s) to develop to free-living adults instead of iL3 at 37°C, while 69.4±12.0% (SD) of post-parasitic L1s developed to iL3 in controls. Second, we found that 1 μM Δ7-DA prevented post-free-living iL3 arrest and stimulated 85.2±16.9% of larvae to develop to free-living rhabditiform third- and fourth-stages, compared to 0% in the control. This induction required 24–48 hours of Δ7-DA exposure. Third, we found that the CYP inhibitor ketoconazole prevented iL3 feeding in host-like conditions, with only 5.6±2.9% of iL3 feeding in 40 μM ketoconazole, compared to 98.8±0.4% in the positive control. This inhibition was partially rescued by Δ7-DA, with 71.2±16.4% of iL3 feeding in 400 nM Δ7-DA and 35 μM ketoconazole, providing the first evidence of endogenous DA production in S. stercoralis. We then characterized the 26 CYP-encoding genes in S. stercoralis and identified a homolog with sequence and developmental regulation similar to DAF-9. Overall, these data demonstrate that DAF-12 signaling regulates S. stercoralis development, showing that in the post-parasitic generation, loss of DAF-12 signaling favors iL3 arrest, while increased DAF-12 signaling favors reproductive development; that in the post-free-living generation, absence of DAF-12 signaling is crucial for iL3 arrest

  2. Intentional self-regulation, ecological assets, and thriving in adolescence: a developmental systems model.

    PubMed

    Gestsdottir, Steinunn; Urban, Jennifer Brown; Bowers, Edmond P; Lerner, Jacqueline V; Lerner, Richard M

    2011-01-01

    The positive youth development (PYD) perspective emphasizes that thriving occurs when individual ↔context relations involve the alignment of adolescent strengths with the resources in their contexts. The authors propose that a key component of this relational process is the strength that youth possess in the form of self-regulatory processes; these processes optimize opportunities to obtain ecological resources that enhance the probability of PYD.  They use the selection, optimization, and compensation (SOC) model of intentional self-regulation to discuss the role of self-regulation in the PYD perspective among diverse youth.

  3. Developmentally regulated impediments to skin reinnervation by injured peripheral sensory axon terminals.

    PubMed

    O'Brien, Georgeann S; Martin, Seanna M; Söllner, Christian; Wright, Gavin J; Becker, Catherina G; Portera-Cailliau, Carlos; Sagasti, Alvaro

    2009-12-29

    The structural plasticity of neurites in the central nervous system (CNS) diminishes dramatically after initial development, but the peripheral nervous system (PNS) retains substantial plasticity into adulthood. Nevertheless, functional reinnervation by injured peripheral sensory neurons is often incomplete [1-6]. To investigate the developmental control of skin reinnervation, we imaged the regeneration of trigeminal sensory axon terminals in live zebrafish larvae following laser axotomy. When axons were injured during early stages of outgrowth, regenerating and uninjured axons grew into denervated skin and competed with one another for territory. At later stages, after the establishment of peripheral arbor territories, the ability of uninjured neighbors to sprout diminished severely, and although injured axons reinitiated growth, they were repelled by denervated skin. Regenerating axons were repelled specifically by their former territories, suggesting that local inhibitory factors persist in these regions. Antagonizing the function of several members of the Nogo receptor (NgR)/RhoA pathway improved the capacity of injured axons to grow into denervated skin. Thus, as in the CNS, impediments to reinnervation in the PNS arise after initial establishment of axon arbor structure.

  4. Clique of functional hubs orchestrates population bursts in developmentally regulated neural networks.

    PubMed

    Luccioli, Stefano; Ben-Jacob, Eshel; Barzilai, Ari; Bonifazi, Paolo; Torcini, Alessandro

    2014-09-01

    It has recently been discovered that single neuron stimulation can impact network dynamics in immature and adult neuronal circuits. Here we report a novel mechanism which can explain in neuronal circuits, at an early stage of development, the peculiar role played by a few specific neurons in promoting/arresting the population activity. For this purpose, we consider a standard neuronal network model, with short-term synaptic plasticity, whose population activity is characterized by bursting behavior. The addition of developmentally inspired constraints and correlations in the distribution of the neuronal connectivities and excitabilities leads to the emergence of functional hub neurons, whose stimulation/deletion is critical for the network activity. Functional hubs form a clique, where a precise sequential activation of the neurons is essential to ignite collective events without any need for a specific topological architecture. Unsupervised time-lagged firings of supra-threshold cells, in connection with coordinated entrainments of near-threshold neurons, are the key ingredients to orchestrate population activity.

  5. Mutational analyses of fs(1)Ya, an essential, developmentally regulated, nuclear envelope protein in Drosophila

    SciTech Connect

    Liu, Jun; Song, Kiwon; Wolfner, M.F.

    1995-12-01

    The fs(1)Ya protein (YA) is an essential, maternally encoded, nuclear lamina protein that is under both developmental and cell cycle control. A strong Ya mutation results in early arrest of embryos. To define the function of YA in the nuclear envelope during early embryonic development, we characterized the phenotypes of four Ya mutant alleles and determined their molecular lesions. Ya mutant embryos arrest with abnormal nuclear envelopes prior to the first mitotic division; a proportion of embryos from two leaky Ya mutants proceed beyond this but arrest after several abnormal divisions. Ya unfertilized eggs contain nuclei of different sizes and condensation states, apparently due to abnormal fusion of the meiotic products immediately after meiosis. Lamin is localized at the periphery of the uncondensed nuclei in these eggs. These results suggest that Ya function is required during and after egg maturation to facilitate proper chromatin condensation, rather than to allow a lamin-containing nuclear envelope to form. Two leaky Ya alleles that partially complement have lesions at opposite ends of the YA protein, suggesting that the N- and C-termini are important for YA function might interact with itself either directly or indirectly. 27 refs., 6 figs.

  6. Developmental Regulation Is Altered in the Calyx during in Vitro Ovary Culture of Tomato.

    PubMed

    Ishida, B. K.

    1991-03-01

    To develop a system with which to study fruit ripening, in vitro ovary cultures were initiated from tomato flowers. As reported previously [Nitsch, J.P. (1951). Am. J. Bot. 38, 566-577], tomato fruit ripened after 6 to 7 weeks, but calyces swelled unexpectedly, lost their green color, and gradually became red and succulent. Investigations were conducted, therefore, to verify the occurrence of the ripening process in the calyx. Ethylene production increased in both ripening fruit and red calyx, as did tissue contents of its immediate precursor, 1-aminocyclopropane-1-carboxylic acid. In addition, an increase in the mRNA of polygalacturonase [poly(1,4-[alpha]-D-galacturonide) glucanohydrolase, EC 3.2.1.15], an enzyme that in tomato is present in large amounts only in ripening fruit, was established in both ripe fruit and red calyx by RNA gel blot analysis. Ultrastructural studies showed that the disruption of cell walls in red calyx was indistinguishable from that occurring in ripe tomato fruit. Thus, the developmental program of the calyx changed in several aspects to resemble that of tomato fruit.

  7. NeuroD1: developmental expression and regulated genes in the rodent pineal gland.

    PubMed

    Muñoz, Estela M; Bailey, Michael J; Rath, Martin F; Shi, Qiong; Morin, Fabrice; Coon, Steven L; Møller, Morten; Klein, David C

    2007-08-01

    NeuroD1/BETA2, a member of the bHLH transcription factor family, is known to influence the fate of specific neuronal, endocrine and retinal cells. We report here that NeuroD1 mRNA is highly abundant in the developing and adult rat pineal gland. Pineal expression begins in the 17-day embryo at which time it is also detectable in other brain regions. Expression in the pineal gland increases during the embryonic period and is maintained thereafter at levels equivalent to those found in the cerebellum and retina. In contrast, NeuroD1 mRNA decreases markedly in non-cerebellar brain regions during development. Pineal NeuroD1 levels are similar during the day and night, and do not appear to be influenced by sympathetic neural input. Gene expression analysis of the pineal glands from neonatal NeuroD1 knockout mice identifies 127 transcripts that are down-regulated (>twofold, p < 0.05) and 16 that are up-regulated (>twofold, p < 0.05). According to quantitative RT-PCR, the most dramatically down-regulated gene is kinesin family member 5C ( approximately 100-fold) and the most dramatically up-regulated gene is glutamic acid decarboxylase 1 ( approximately fourfold). Other impacted transcripts encode proteins involved in differentiation, development, signal transduction and trafficking. These findings represent the first step toward elucidating the role of NeuroD1 in the rodent pinealocyte.

  8. Toward a Developmental Model of Child Compliance: The Role of Emotion Regulation in Infancy.

    ERIC Educational Resources Information Center

    Stifter, Cynthia A.; Spinrad, Tracy L.; Braungart-Rieker, Julia M.

    1999-01-01

    Examined relationship between emotion regulation at ages 5, 10, and 18 months, and compliance at 30 months. Found that infants with low levels of regulatory behavior were more likely to be noncompliant as toddlers. High cardiac vagal tone was related to noncompliance to toy clean-up, whereas low cardiac vagal tone was related to noncompliance to…

  9. The History of Legislation and Regulations Related to Children with Developmental Disabilities: Implications for School Nursing Practice Today

    ERIC Educational Resources Information Center

    Dang, Michelle T.

    2010-01-01

    A significant number of children in the United States have developmental disabilities. Historically, many children with developmental disabilities were institutionalized and rarely seen in public. Currently, children with developmental disabilities are entitled to education and health-related support services that permit them access to public…

  10. Evidence for regulation of mitotic progression through temporal phosphorylation and dephosphorylation of CK2alpha.

    PubMed

    St-Denis, Nicole A; Derksen, D Richard; Litchfield, David W

    2009-04-01

    Proper mitotic progression is crucial for maintenance of genomic integrity in proliferating cells and is regulated through an intricate series of events, including protein phosphorylation governed by a complex network of protein kinases. One kinase family implicated in the regulation of mitotic progression is protein kinase CK2, a small family of enzymes that is overexpressed in cancer and induces transformation in mice and cultured fibroblasts. CK2alpha, one isoform of the catalytic subunits of CK2, is maximally phosphorylated at four sites in nocodazole-treated cells. To investigate the effects of CK2alpha phosphorylation on mitotic progression, we generated phosphospecific antibodies against its mitotic phosphorylation sites. In U2OS cells released from S-phase arrest, these antibodies reveal that CK2alpha is most highly phosphorylated in prophase and metaphase. Phosphorylation gradually decreases during anaphase and becomes undetectable during telophase and cytokinesis. Stable expression of phosphomimetic CK2alpha (CK2alpha-4D, CK2alpha-4E) results in aberrant centrosome amplification and chromosomal segregation defects and loss of mitotic cells through mitotic catastrophe. Conversely, cells expressing nonphosphorylatable CK2alpha (CK2alpha-4A) show a decreased ability to arrest in mitosis following nocodazole treatment, suggesting involvement in the spindle assembly checkpoint. Collectively, these studies indicate that reversible phosphorylation of CK2alpha requires precise regulation to allow proper mitotic progression.

  11. FOXM1 participates in PLK1-regulated cell cycle progression in renal cell cancer cells

    PubMed Central

    ZHANG, ZHE; ZHANG, GUOJUN; KONG, CHUIZE

    2016-01-01

    The regulation of entry into and progression through mitosis is important for cell proliferation. Polo-like kinase 1 (PLK1) is involved in multiple stages of mitosis. Forkhead box protein M1 (FOXM1) has multiple functions in tumorigenesis and, in elevated levels, is frequently associated with cancer progression. The present study reports that FOXM1, a substrate of PLK1, controls the transcription mechanism that mediates the PLK1-dependent regulation of the cell cycle. The present study investigated the expression of PLK1 and FOXM1 in the clear renal cell carcinoma 769-P and ACHN cell lines, and indicated that the expression of PLK1 and FOXM1 are correlated in human renal cell cancer cell lines and that the suppression of PLK1 may decrease the expression of FOXM1. The knockdown of FOXM1 or PLK1 in renal cell cancer cell lines caused cell cycle progression to be blocked. As a result, the present study indicated the involvement of FOXM1 in PLK1-regulated cell cycle progression. PMID:27073539

  12. Progressive tarsal patterning in the Drosophila by temporally dynamic regulation of transcription factor genes.

    PubMed

    Natori, Kohei; Tajiri, Reiko; Furukawa, Shiori; Kojima, Tetsuya

    2012-01-15

    The morphology of insect appendages, such as the number and proportion of leg tarsal segments, is immensely diverse. In Drosophila melanogaster, adult legs have five tarsal segments. Accumulating evidence indicates that tarsal segments are formed progressively through dynamic changes in the expression of transcription factor genes, such as Bar genes, during development. In this study, to examine further the basis of progressive tarsal patterning, the precise expression pattern and function of several transcription factor genes were investigated in relation to the temporal regulation of Bar expression. The results indicate that nubbin is expressed over a broad region at early stages but gradually disappears from the middle of the tarsal region. This causes the progressive expansion of rotund expression, which in turn progressively represses Bar expression, leading to the formation of the tarsal segment 3. The region corresponding to the tarsal segment 4 is formed when apterous expression is initiated, which renders Bar expression refractory to rotund. In addition, the tarsal segment 2 appears to be derived from the region that expresses Bar at a very early stage. Cessation of Bar expression in this region requires the function of spineless, which also regulates rotund expression. These findings indicate that the temporally dynamic regulatory interaction of these transcription factor genes is the fundamental basis of the progressive patterning of the tarsal region.

  13. Structural and Functional Features of a Developmentally Regulated Lipopolysaccharide-Binding Protein

    PubMed Central

    Krasity, Benjamin C.; Troll, Joshua V.; Lehnert, Erik M.; Hackett, Kathleen T.; Dillard, Joseph P.; Apicella, Michael A.; Goldman, William E.

    2015-01-01

    ABSTRACT Mammalian lipopolysaccharide (LPS) binding proteins (LBPs) occur mainly in extracellular fluids and promote LPS delivery to specific host cell receptors. The function of LBPs has been studied principally in the context of host defense; the possible role of LBPs in nonpathogenic host-microbe interactions has not been well characterized. Using the Euprymna scolopes-Vibrio fischeri model, we analyzed the structure and function of an LBP family protein, E. scolopes LBP1 (EsLBP1), and provide evidence for its role in triggering a symbiont-induced host developmental program. Previous studies showed that, during initial host colonization, the LPS of V. fischeri synergizes with peptidoglycan (PGN) monomer to induce morphogenesis of epithelial tissues of the host animal. Computationally modeled EsLBP1 shares some but not all structural features of mammalian LBPs that are thought important for LPS binding. Similar to human LBP, recombinant EsLBP1 expressed in insect cells bound V. fischeri LPS and Neisseria meningitidis lipooligosaccharide (LOS) with nanomolar or greater affinity but bound Francisella tularensis LPS only weakly and did not bind PGN monomer. Unlike human LBP, EsLBP1 did not bind N. meningitidis LOS:CD14 complexes. The eslbp1 transcript was upregulated ~22-fold by V. fischeri at 24 h postinoculation. Surprisingly, this upregulation was not induced by exposure to LPS but, rather, to the PGN monomer alone. Hybridization chain reaction-fluorescent in situ hybridization (HCR-FISH) and immunocytochemistry (ICC) localized eslbp1 transcript and protein in crypt epithelia, where V. fischeri induces morphogenesis. The data presented here provide a window into the evolution of LBPs and the scope of their roles in animal symbioses. PMID:26463160

  14. Astroglial cells regulate the developmental timeline of human neurons differentiated from induced pluripotent stem cells.

    PubMed

    Tang, Xin; Zhou, Li; Wagner, Alecia M; Marchetto, Maria C N; Muotri, Alysson R; Gage, Fred H; Chen, Gong

    2013-09-01

    Neurons derived from human induced-pluripotent stem cells (hiPSCs) have been used to model a variety of neurological disorders. Different protocols have been used to differentiate hiPSCs into neurons, but their functional maturation process has varied greatly among different studies. Here, we demonstrate that laminin, a commonly used substrate for iPSC cultures, was inefficient to promote fully functional maturation of hiPSC-derived neurons. In contrast, astroglial substrate greatly accelerated neurodevelopmental processes of hiPSC-derived neurons. We have monitored the neural differentiation and maturation process for up to two months after plating hiPSC-derived neuroprogenitor cells (hNPCs) on laminin or astrocytes. We found that one week after plating hNPCs, there were 21-fold more newly differentiated neurons on astrocytes than on laminin. Two weeks after plating hNPCs, there were 12-fold more dendritic branches in neurons cultured on astrocytes than on laminin. Six weeks after plating hNPCs, the Na(+) and K(+) currents, as well as glutamate and GABA receptor currents, were 3-fold larger in neurons cultured on astrocytes than on laminin. And two months after plating hNPCs, the spontaneous synaptic events were 8-fold more in neurons cultured on astrocytes than on laminin. These results highlight a critical role of astrocytes in promoting neural differentiation and functional maturation of human neurons derived from hiPSCs. Moreover, our data presents a thorough developmental timeline of hiPSC-derived neurons in culture, providing important benchmarks for future studies on disease modeling and drug screening.

  15. Astroglial cells regulate the developmental timeline of human neurons differentiated from induced pluripotent stem cells

    PubMed Central

    Tang, Xin; Zhou, Li; Wagner, Alecia M.; Marchetto, Maria C.N.; Muotri, Alysson R.; Gage, Fred H.; Chen, Gong

    2014-01-01

    Neurons derived from human induced-pluripotent stem cells (hiPSCs) have been used to model a variety of neurological disorders. Different protocols have been used to differentiate hiPSCs into neurons, but their functional maturation process has varied greatly among different studies. Here, we demonstrate that laminin, a commonly used substrate for iPSC cultures, was inefficient to promote fully functional maturation of hiPSC-derived neurons. In contrast, astroglial substrate greatly accelerated neurodevelopmental processes of hiPSC-derived neurons. We have monitored the neural differentiation and maturation process for up to two months after plating hiPSC-derived neuroprogenitor cells (hNPCs) on laminin or astrocytes. We found that one week after plating hNPCs, there were 21-fold more newly differentiated neurons on astrocytes than on laminin. Two weeks after plating hNPCs, there were 12-fold more dendritic branches in neurons cultured on astrocytes than on laminin. Six weeks after plating hNPCs, the Na+ and K+ currents, as well as glutamate and GABA receptor currents, were 3-fold larger in neurons cultured on astrocytes than on laminin. And two months after plating hNPCs, the spontaneous synaptic events were 8-fold more in neurons cultured on astrocytes than on laminin. These results highlight a critical role of astrocytes in promoting neural differentiation and functional maturation of human neurons derived from hiPSCs. Moreover, our data presents a thorough developmental timeline of hiPSC-derived neurons in culture, providing important benchmarks for future studies on disease modeling and drug screening. PMID:23759711

  16. Abundance of amino acid transporters involved in mTORC1 activation in skeletal muscle of neonatal pigs is developmentally regulated

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Previously we demonstrated that the insulinand amino acid-induced activation of the mammalian target of rapamycin complex 1 (mTORC1) is developmentally regulated in neonatal pigs. Recent studies have indicated that members of the System A transporter (SNAT2), the System N transporter (SNAT3), the Sy...

  17. Curcumin inhibits cancer progression through regulating expression of microRNAs.

    PubMed

    Zhou, Siying; Zhang, Sijie; Shen, Hongyu; Chen, Wei; Xu, Hanzi; Chen, Xiu; Sun, Dawei; Zhong, Shanliang; Zhao, Jianhua; Tang, Jinhai

    2017-02-01

    Curcumin, a major yellow pigment and spice in turmeric and curry, is a powerful anti-cancer agent. The anti-tumor activities of curcumin include inhibition of tumor proliferation, angiogenesis, invasion and metastasis, induction of tumor apoptosis, increase of chemotherapy sensitivity, and regulation of cell cycle and cancer stem cell, indicating that curcumin maybe a strong therapeutic potential through modulating various cancer progression. It has been reported that microRNAs as small noncoding RNA molecules are related to cancer progression, which can be regulated by curcumin. Dysregulated microRNAs play vital roles in tumor biology via regulating expressions of target genes and then influencing multiple cancer-related signaling pathways. In this review, we focused on the inhibition effect of curcumin on various cancer progression by regulating expression of multiple microRNAs. Curcumin-induced dysregulation of microRNAs may activate or inactivate a set of signaling pathways, such as Akt, Bcl-2, PTEN, p53, Notch, and Erbb signaling pathways. A better understanding of the relation between curcumin and microRNAs may provide a potential therapeutic target for various cancers.

  18. PEG-3, a nontransforming cancer progression gene, is a positive regulator of cancer aggressiveness and angiogenesis.

    PubMed

    Su, Z Z; Goldstein, N I; Jiang, H; Wang, M N; Duigou, G J; Young, C S; Fisher, P B

    1999-12-21

    Cancer is a progressive disease culminating in acquisition of metastatic potential by a subset of evolving tumor cells. Generation of an adequate blood supply in tumors by production of new blood vessels, angiogenesis, is a defining element in this process. Although extensively investigated, the precise molecular events underlying tumor development, cancer progression, and angiogenesis remain unclear. Subtraction hybridization identified a genetic element, progression elevated gene-3 (PEG-3), whose expression directly correlates with cancer progression and acquisition of oncogenic potential by transformed rodent cells. We presently demonstrate that forced expression of PEG-3 in tumorigenic rodent cells, and in human cancer cells, increases their oncogenic potential in nude mice as reflected by a shorter tumor latency time and the production of larger tumors with increased vascularization. Moreover, inhibiting endogenous PEG-3 expression in progressed rodent cancer cells by stable expression of an antisense expression vector extinguishes the progressed cancer phenotype. Cancer aggressiveness of PEG-3 expressing rodent cells correlates directly with increased RNA transcription, elevated mRNA levels, and augmented secretion of vascular endothelial growth factor (VEGF). Furthermore, transient ectopic expression of PEG-3 transcriptionally activates VEGF in transformed rodent and human cancer cells. Taken together these data demonstrate that PEG-3 is a positive regulator of cancer aggressiveness, a process regulated by augmented VEGF production. These studies also support an association between expression of a single nontransforming cancer progression-inducing gene, PEG-3, and the processes of cancer aggressiveness and angiogenesis. In these contexts, PEG-3 may represent an important target molecule for developing cancer therapeutics and inhibitors of angiogenesis.

  19. Chromatin boundary elements organize genomic architecture and developmental gene regulation in Drosophila Hox clusters

    PubMed Central

    Ma, Zhibo; Li, Mo; Roy, Sharmila; Liu, Kevin J; Romine, Matthew L; Lane, Derrick C; Patel, Sapna K; Cai, Haini N

    2016-01-01

    The three-dimensional (3D) organization of the eukaryotic genome is critical for its proper function. Evidence suggests that extensive chromatin loops form the building blocks of the genomic architecture, separating genes and gene clusters into distinct functional domains. These loops are anchored in part by a special type of DNA elements called chromatin boundary elements (CBEs). CBEs were originally found to insulate neighboring genes by blocking influences of transcriptional enhancers or the spread of silent chromatin. However, recent results show that chromatin loops can also play a positive role in gene regulation by looping out intervening DNA and “delivering” remote enhancers to gene promoters. In addition, studies from human and model organisms indicate that the configuration of chromatin loops, many of which are tethered by CBEs, is dynamically regulated during cell differentiation. In particular, a recent work by Li et al has shown that the SF1 boundary, located in the Drosophila Hox cluster, regulates local genes by tethering different subsets of chromatin loops: One subset enclose a neighboring gene ftz, limiting its access by the surrounding Scr enhancers and restrict the spread of repressive histones during early embryogenesis; and the other loops subdivide the Scr regulatory region into independent domains of enhancer accessibility. The enhancer-blocking activity of these CBE elements varies greatly in strength and tissue distribution. Further, tandem pairing of SF1 and SF2 facilitate the bypass of distal enhancers in transgenic flies, providing a mechanism for endogenous enhancers to circumvent genomic interruptions resulting from chromosomal rearrangement. This study demonstrates how a network of chromatin boundaries, centrally organized by SF1, can remodel the 3D genome to facilitate gene regulation during development. PMID:27621770

  20. Developmentally regulated expression of the regulator of G-protein signaling gene 2 (Rgs2) in the embryonic mouse pituitary.

    PubMed

    Wilson, L D; Ross, S A; Lepore, D A; Wada, T; Penninger, J M; Thomas, P Q

    2005-02-01

    During the development of the anterior pituitary gland, five distinct hormone-producing cell types emerge in a spatially and temporally regulated pattern from an invagination of oral ectoderm termed Rathke's Pouch. Evidence from mouse knockout and ectopic expression studies indicates that 12.5 days post coitum (dpc) to 14.5 dpc is a critical period for the expansion of the progenitor cell pool and the determination of most hormone-secreting cell types. While signaling proteins and transcription factors have been identified as having key roles in pituitary cell differentiation, little is known about the identity and function of proteins that mediate signal transduction in progenitor cells. To identify genes that are enriched in the embryonic pituitary gland, we compared gene expression in 14.5 dpc pituitary and 14.5 dpc embryo minus pituitary tissues using the NIA 15K microarray. Analysis of the data using the R program revealed that the Regulator of G Protein Signaling 2 (Rgs2) gene was 3.9-fold more abundant in the 14.5 dpc pituitary. In situ hybridisation confirmed this finding, and showed that Rgs2 expression in midline tissues was restricted to the pituitary and discrete regions of the nervous system. Within the pituitary, Rgs2 was expressed in undifferentiated cells, and was downregulated at the completion of the hormone cell differentiation. To investigate Rgs2 function in the pituitary, we examined hormone cell differentiation in Rgs2 null neonate mice. Pituitary cell differentiation and morphology appeared normal in the Rgs2 mutant animals, suggesting that other Rgs family members with similar activities may be present in the developing pituitary.

  1. Developmental Toxicity of Diclofenac and Elucidation of Gene Regulation in zebrafish (Danio rerio)

    NASA Astrophysics Data System (ADS)

    Chen, Jia-Bin; Gao, Hong-Wen; Zhang, Ya-Lei; Zhang, Yong; Zhou, Xue-Fei; Li, Chun-Qi; Gao, Hai-Ping

    2014-05-01

    Environmental pollution by emerging contaminants, e.g. pharmaceuticals, has become a matter of widespread concern in recent years. We investigated the membrane transport of diclofenac and its toxic effects on gene expression and the development of zebrafish embryos. The association of diclofenac with the embryos conformed to the general partition model at low concentration, the partition coefficient being 0.0033 ml per embryo. At high concentration, the interaction fitted the Freundlich model. Most of the diclofenac remained in the extracellular aqueous solution with less than 5% interacting with the embryo, about half of which was adsorbed on the membranes while the rest entered the cytoplasm. Concentrations of diclofenac over 10.13 μM were lethal to all the embryos, while 3.78 μM diclofenac was teratogenic. The development abnormalities at 4 day post treatment (dpt) include shorter body length, smaller eye, pericardial and body edema, lack of liver, intestine and circulation, muscle degeneration, and abnormal pigmentation. The portion of the diclofenac transferred into the embryo altered the expression of certain genes, e.g. down-regulation of Wnt3a and Gata4 and up-regulation of Wnt8a. The alteration of expression of such genes or the regulation of downstream genes could cause defects in the cardiovascular and nervous systems.

  2. Developmental expression of the SRF co-activator MAL in brain: role in regulating dendritic morphology.

    PubMed

    Shiota, Jun; Ishikawa, Mitsuru; Sakagami, Hiroyuki; Tsuda, Masaaki; Baraban, Jay M; Tabuchi, Akiko

    2006-09-01

    The dynamic changes in dendritic morphology displayed by developing and mature neurons have stimulated interest in deciphering the signaling pathways involved. Recent studies have identified megakaryocytic acute leukemia (MAL), a serum response factor (SRF) co-activator, as a key component of a signaling pathway linking changes in the actin cytoskeleton to SRF-mediated transcription. To help define the role of this pathway in regulating dendritic morphology, we have characterized the pattern of MAL expression in the developing and adult brain, and have examined its role in regulating dendritic morphology in cultured cortical neurons. In histological studies of mouse brain, we found prominent expression of MAL in neurons in adult hippocampus and cerebral cortex. MAL immunostaining revealed localization of this protein in neuronal cell bodies and apical dendrites. During development, an increase in MAL expression occurs during the second post-natal week. Expression of dominant negative MAL constructs or MAL siRNA in cortical neurons grown in primary culture reduces the number of dendritic processes and decreases the basal level of SRF-mediated transcription. Taken together, these findings indicate that the MAL-SRF signaling pathway plays a key role in regulating dendritic morphology.

  3. Spatial Regulation of Root Growth: Placing the Plant TOR Pathway in a Developmental Perspective.

    PubMed

    Barrada, Adam; Montané, Marie-Hélène; Robaglia, Christophe; Menand, Benoît

    2015-08-19

    Plant cells contain specialized structures, such as a cell wall and a large vacuole, which play a major role in cell growth. Roots follow an organized pattern of development, making them the organs of choice for studying the spatio-temporal regulation of cell proliferation and growth in plants. During root growth, cells originate from the initials surrounding the quiescent center, proliferate in the division zone of the meristem, and then increase in length in the elongation zone, reaching their final size and differentiation stage in the mature zone. Phytohormones, especially auxins and cytokinins, control the dynamic balance between cell division and differentiation and therefore organ size. Plant growth is also regulated by metabolites and nutrients, such as the sugars produced by photosynthesis or nitrate assimilated from the soil. Recent literature has shown that the conserved eukaryotic TOR (target of rapamycin) kinase pathway plays an important role in orchestrating plant growth. We will summarize how the regulation of cell proliferation and cell expansion by phytohormones are at the heart of root growth and then discuss recent data indicating that the TOR pathway integrates hormonal and nutritive signals to orchestrate root growth.

  4. The Developmental Intestinal Regulator ELT-2 Controls p38-Dependent Immune Responses in Adult C. elegans

    PubMed Central

    Block, Dena H. S.; Twumasi-Boateng, Kwame; Kang, Hae Sung; Carlisle, Jolie A.; Hanganu, Alexandru; Lai, Ty Yu-Jen; Shapira, Michael

    2015-01-01

    GATA transcription factors play critical roles in cellular differentiation and development. However, their roles in mature tissues are less understood. In C. elegans larvae, the transcription factor ELT-2 regulates terminal differentiation of the intestine. It is also expressed in the adult intestine, where it was suggested to maintain intestinal structure and function, and where it was additionally shown to contribute to infection resistance. To study the function of elt-2 in adults we characterized elt-2-dependent gene expression following its knock-down specifically in adults. Microarray analysis identified two ELT-2-regulated gene subsets: one, enriched for hydrolytic enzymes, pointed at regulation of constitutive digestive functions as a dominant role of adult elt-2; the second was enriched for immune genes that are induced in response to Pseudomonas aeruginosa infection. Focusing on the latter, we used genetic analyses coupled to survival assays and quantitative RT-PCR to interrogate the mechanism(s) through which elt-2 contributes to immunity. We show that elt-2 controls p38-dependent gene induction, cooperating with two p38-activated transcription factors, ATF-7 and SKN-1. This demonstrates a mechanism through which the constitutively nuclear elt-2 can impact induced responses, and play a dominant role in C. elegans immunity. PMID:26016853

  5. The Developmental Basis of Epigenetic Regulation of HTR2A and Psychiatric Outcomes

    PubMed Central

    Paquette, Alison G.; Marsit, Carmen J.

    2014-01-01

    The serotonin receptor 5-HT2A (encoded by HTR2A) is an important regulator of fetal brain development and adult cognitive function. Environmental signals that induce epigenetic changes of serotonin response genes, including HTR2A, have been implicated in adverse mental health outcomes. The objective of this perspective article is to address the medical implications of HTR2A epigenetic regulation, which has been associated with both infant neurobehavioral outcomes and adult mental health. Ongoing research has identified a region of the HTR2A promoter that has been associated with a number of medical outcomes in adults and infants, including bipolar disorder, schizophrenia, chronic fatigue syndrome, borderline personality disorder, suicidality, and neurobehavioral outcomes. Epigenetic regulation of HTR2A has been studied in several different types of tissues, including the placenta. The placenta is an important source of serotonin during fetal neurodevelopment, and placental epigenetic variation of HTR2A has been associated with infant neurobehavioral outcomes, which may represent the basis of adult mental health disorders. Further analysis is needed to identify intrinsic and extrinsic factors modulate HTR2A methylation, and the mechanism by which this epigenetic variation influences fetal growth and leads to altered brain development, manifesting in psychiatric disorders. PMID:25043477

  6. Developmental Toxicity of Diclofenac and Elucidation of Gene Regulation in zebrafish (Danio rerio)

    PubMed Central

    Chen, Jia-Bin; Gao, Hong-Wen; Zhang, Ya-Lei; Zhang, Yong; Zhou, Xue-Fei; Li, Chun-Qi; Gao, Hai-Ping

    2014-01-01

    Environmental pollution by emerging contaminants, e.g. pharmaceuticals, has become a matter of widespread concern in recent years. We investigated the membrane transport of diclofenac and its toxic effects on gene expression and the development of zebrafish embryos. The association of diclofenac with the embryos conformed to the general partition model at low concentration, the partition coefficient being 0.0033 ml per embryo. At high concentration, the interaction fitted the Freundlich model. Most of the diclofenac remained in the extracellular aqueous solution with less than 5% interacting with the embryo, about half of which was adsorbed on the membranes while the rest entered the cytoplasm. Concentrations of diclofenac over 10.13 μM were lethal to all the embryos, while 3.78 μM diclofenac was teratogenic. The development abnormalities at 4 day post treatment (dpt) include shorter body length, smaller eye, pericardial and body edema, lack of liver, intestine and circulation, muscle degeneration, and abnormal pigmentation. The portion of the diclofenac transferred into the embryo altered the expression of certain genes, e.g. down-regulation of Wnt3a and Gata4 and up-regulation of Wnt8a. The alteration of expression of such genes or the regulation of downstream genes could cause defects in the cardiovascular and nervous systems. PMID:24788080

  7. Developmental regulation of N-terminal H2B methylation in Drosophila melanogaster

    PubMed Central

    Villar-Garea, Ana; Forne, Ignasi; Vetter, Irene; Kremmer, Elisabeth; Thomae, Andreas; Imhof, Axel

    2012-01-01

    Histone post-translational modifications play an important role in regulating chromatin structure and gene expression in vivo. Extensive studies investigated the post-translational modifications of the core histones H3 and H4 or the linker histone H1. Much less is known on the regulation of H2A and H2B modifications. Here, we show that a major modification of H2B in Drosophila melanogaster is the methylation of the N-terminal proline, which increases during fly development. Experiments performed in cultured cells revealed higher levels of H2B methylation when cells are dense, regardless of their cell cycle distribution. We identified dNTMT (CG1675) as the enzyme responsible for H2B methylation. We also found that the level of N-terminal methylation is regulated by dART8, an arginine methyltransferase that physically interacts with dNTMT and asymmetrically methylates H3R2. Our results demonstrate the existence of a complex containing two methyltransferases enzymes, which negatively influence each other’s activity. PMID:22053083

  8. The Developmental Intestinal Regulator ELT-2 Controls p38-Dependent Immune Responses in Adult C. elegans.

    PubMed

    Block, Dena H S; Twumasi-Boateng, Kwame; Kang, Hae Sung; Carlisle, Jolie A; Hanganu, Alexandru; Lai, Ty Yu-Jen; Shapira, Michael

    2015-05-01

    GATA transcription factors play critical roles in cellular differentiation and development. However, their roles in mature tissues are less understood. In C. elegans larvae, the transcription factor ELT-2 regulates terminal differentiation of the intestine. It is also expressed in the adult intestine, where it was suggested to maintain intestinal structure and function, and where it was additionally shown to contribute to infection resistance. To study the function of elt-2 in adults we characterized elt-2-dependent gene expression following its knock-down specifically in adults. Microarray analysis identified two ELT-2-regulated gene subsets: one, enriched for hydrolytic enzymes, pointed at regulation of constitutive digestive functions as a dominant role of adult elt-2; the second was enriched for immune genes that are induced in response to Pseudomonas aeruginosa infection. Focusing on the latter, we used genetic analyses coupled to survival assays and quantitative RT-PCR to interrogate the mechanism(s) through which elt-2 contributes to immunity. We show that elt-2 controls p38-dependent gene induction, cooperating with two p38-activated transcription factors, ATF-7 and SKN-1. This demonstrates a mechanism through which the constitutively nuclear elt-2 can impact induced responses, and play a dominant role in C. elegans immunity.

  9. Spatial Regulation of Root Growth: Placing the Plant TOR Pathway in a Developmental Perspective

    PubMed Central

    Barrada, Adam; Montané, Marie-Hélène; Robaglia, Christophe; Menand, Benoît

    2015-01-01

    Plant cells contain specialized structures, such as a cell wall and a large vacuole, which play a major role in cell growth. Roots follow an organized pattern of development, making them the organs of choice for studying the spatio-temporal regulation of cell proliferation and growth in plants. During root growth, cells originate from the initials surrounding the quiescent center, proliferate in the division zone of the meristem, and then increase in length in the elongation zone, reaching their final size and differentiation stage in the mature zone. Phytohormones, especially auxins and cytokinins, control the dynamic balance between cell division and differentiation and therefore organ size. Plant growth is also regulated by metabolites and nutrients, such as the sugars produced by photosynthesis or nitrate assimilated from the soil. Recent literature has shown that the conserved eukaryotic TOR (target of rapamycin) kinase pathway plays an important role in orchestrating plant growth. We will summarize how the regulation of cell proliferation and cell expansion by phytohormones are at the heart of root growth and then discuss recent data indicating that the TOR pathway integrates hormonal and nutritive signals to orchestrate root growth. PMID:26295391

  10. Physarum polycephalum mutants in the photocontrol of sporulation display altered patterns in the correlated expression of developmentally regulated genes.

    PubMed

    Rätzel, Viktoria; Ebeling, Britta; Hoffmann, Xenia-Katharina; Tesmer, Jens; Marwan, Wolfgang

    2013-02-01

    Physarum polycephalum is a lower eukaryote belonging to the amoebozoa group of organisms that forms macroscopic, multinucleate plasmodial cells during its developmental cycle. Plasmodia can exit proliferative growth and differentiate by forming fruiting bodies containing mononucleate, haploid spores. This process, called sporulation, is controlled by starvation and visible light. To genetically dissect the regulatory control of the commitment to sporulation, we have isolated plasmodial mutants that are altered in the photocontrol of sporulation in a phenotypic screen of N-ethyl-N-nitrosourea (ENU) mutagenized cells. Several non-sporulating mutants were analyzed by measuring the light-induced change in the expression pattern of a set of 35 genes using GeXP multiplex reverse transcription-polymerase chain reaction with RNA isolated from individual plasmodial cells. Mutants showed altered patterns of differentially regulated genes in response to light stimulation. Some genes clearly displayed pairwise correlation in terms of their expression level as measured in individual plasmodial cells. The pattern of pairwise correlation differed in various mutants, suggesting that different upstream regulators were disabled in the different mutants. We propose that patterns of pairwise correlation in gene expression might be useful to infer the underlying gene regulatory network.

  11. Differential Accumulation of Sunflower Tetraubiquitin mRNAs during Zygotic Embryogenesis and Developmental Regulation of Their Heat-Shock Response.

    PubMed Central

    Almoguera, C.; Coca, M. A.; Jordano, J.

    1995-01-01

    We have isolated and sequenced Ha UbiS, a cDNA for a dry-seed-stored mRNA that encodes tetraubiquitin. We have observed differential accumulation of tetraubiquitin mRNAs during sunflower (Helianthus annuus L.) zygotic embryogenesis. These mRNAs were up-regulated during late embryogenesis and reached higher prevalence in the dry seed, where they were found to be associated mainly with provascular tissue. UbiS mRNA, as confirmed by Rnase A protection experiments, accumulated also in response to heat shock, but only in leaves and later during postgerminative development. These novel observations demonstrate expression during seed maturation of specific plant polyubiquitin transcripts and developmental regulation of their heat-shock response. Using ubiquitin antibodies we also detected discrete, seed-specific proteins with distinct temporal expression patterns during zygotic embryogenesis. Some of these patterns were concurrent with UbiS mRNA accumulation in seeds. The most abundant ubiquitin-reacting proteins found in mature seeds were small (16-22 kD) and acidic (isoelectric points of 6.1-7.4). Possible functional implications for UbiS expression elicited from these observations are discussed. PMID:12228401

  12. Developmentally regulated expression of the novel cancer anti-apoptosis gene survivin in human and mouse differentiation.

    PubMed Central

    Adida, C.; Crotty, P. L.; McGrath, J.; Berrebi, D.; Diebold, J.; Altieri, D. C.

    1998-01-01

    Inhibitors of programmed cell death (apoptosis) may regulate tissue differentiation and aberrantly promote cell survival in neoplasia. A novel apoptosis inhibitor of the IAP gene family, designated survivin, was recently found in all of the most common human cancers but not in normal, terminally differentiated adult tissues. The expression of survivin in embryonic and fetal development was investigated. Immunohistochemistry and in situ hybridization studies demonstrated strong expression of survivin in several apoptosis-regulated fetal tissues, including the stem cell layer of stratified epithelia, endocrine pancreas, and thymic medulla, with a pattern that did not overlap with that of another apoptosis inhibitor, bcl-2. A sequence-specific antibody to survivin immunoblotted a single approximately 16.5-kd survivin band in human fetal lung, liver, heart, kidney, and gastrointestinal tract. In mouse embryo, prominent and nearly ubiquitous distribution of survivin was found at embryonic day (E)11.5, whereas at E15 to -21, survivin expression was restricted to the distal bronchiolar epithelium of the lung and neural-crest-derived cells, including dorsal root ganglion neurons, hypophysis, and the choroid plexus. These data suggest that expression of survivin in embryonic and fetal development may contribute to tissue homeostasis and differentiation independently of bcl-2. Aberrations of this developmental pathway may result in prominent re-expression of survivin in neoplasia and abnormally prolonged cell viability. Images Figure 1 Figure 2 Figure 3 Figure 4 PMID:9422522

  13. Arabidopsis ribosomal proteins control vacuole trafficking and developmental programs through the regulation of lipid metabolism

    SciTech Connect

    Li, Ruixi; Sun, Ruobai; Hicks, Glenn R.; Raikhel, Natasha V.

    2014-12-22

    The vacuole is the most prominent compartment in plant cells and is important for ion and protein storage. In our effort to search for key regulators in the plant vacuole sorting pathway, ribosomal large subunit 4 (rpl4d) was identified as a translational mutant defective in both vacuole trafficking and normal development. Polysome profiling of the rpl4d mutant showed reduction in polysome-bound mRNA compared with wild-type, but no significant change in the general mRNA distribution pattern. Ribsomal profiling data indicated that genes in the lipid metabolism pathways were translationally down-regulated in the rpl4d mutant. Live imaging studies by Nile red staining suggested that both polar and nonpolar lipid accumulation was reduced in meristem tissues of rpl4d mutants. Pharmacological evidence showed that sterol and sphingolipid biosynthetic inhibitors can phenocopy the defects of the rpl4d mutant, including an altered vacuole trafficking pattern. Genetic evidence from lipid biosynthetic mutants indicates that alteration in the metabolism of either sterol or sphingolipid biosynthesis resulted in vacuole trafficking defects, similar to the rpl4d mutant. Tissue-specific complementation with key enzymes from lipid biosynthesis pathways can partially rescue both vacuole trafficking and auxin-related developmental defects in the rpl4d mutant. These results indicate that lipid metabolism modulates auxin-mediated tissue differentiation and endomembrane trafficking pathways downstream of ribosomal protein function.

  14. Developmental regulation of N-methyl-D-aspartate- and kainate-type glutamate receptor expression in the rat spinal cord

    NASA Technical Reports Server (NTRS)

    Stegenga, S. L.; Kalb, R. G.

    2001-01-01

    Spinal motor neurons undergo experience-dependent development during a critical period in early postnatal life. It has been suggested that the repertoire of glutamate receptor subunits differs between young and mature motor neurons and contributes to this activity-dependent development. In the present study we examined the expression patterns of N-methyl-D-aspartate- and kainate-type glutamate receptor subunits during the postnatal maturation of the spinal cord. Young motor neurons express much higher levels of the N-methyl-D-aspartate receptor subunit NR1 than do adult motor neurons. Although there are eight potential splice variants of NR1, only a subgroup is expressed by motor neurons. With respect to NR2 receptor subunits, young motor neurons express NR2A and C, while adult motor neurons express only NR2A. Young motor neurons express kainate receptor subunits GluR5, 6 and KA2 but we are unable to detect these or any other kainate receptor subunits in the adult spinal cord. Other spinal cord regions display a distinct pattern of developmental regulation of N-methyl-D-aspartate and kainate receptor subunit expression in comparison to motor neurons. Our findings indicate a precise spatio-temporal regulation of individual subunit expression in the developing spinal cord. Specific combinations of subunits in developing neurons influence their excitable properties and could participate in the emergence of adult neuronal form and function.

  15. Up-regulated A20 promotes proliferation, regulates cell cycle progression and induces chemotherapy resistance of acute lymphoblastic leukemia cells.

    PubMed

    Chen, Shuying; Xing, Haiyan; Li, Shouyun; Yu, Jing; Li, Huan; Liu, Shuang; Tian, Zheng; Tang, Kejing; Rao, Qing; Wang, Min; Wang, Jianxiang

    2015-09-01

    A20, also known as tumor necrosis factor-α (TNFα)-induced protein 3 (TNFAIP3), has been identified as a key regulator of cell survival in many solid tumors. However, little is known about the protein expression level and function of A20 in acute lymphoblastic leukemia (ALL). In this study, we found that A20 is up-regulated in ALL patients and several cell lines. Knockdown of A20 in Jurkat, Nalm-6, and Reh cells resulted in reduced cell proliferation, which was associated with cell cycle arrest. Phospho-ERK (p-ERK) was also down-regulated, while p53 and p21 were up-regulated in A20 knockdown cells. In addition, A20 knockdown induced apoptosis in Jurkat and Reh cells and enhanced the sensitivity of these cell lines to chemotherapeutic drugs. These results indicate that A20 may stimulate cell proliferation by regulating cell cycle progression. A20 inhibited apoptosis in some types of ALL cells, thereby enhancing their resistance to chemotherapy. This effect was abolished through A20 silencing. These findings suggest that A20 may contribute to the pathogenesis of ALL and that it may be used as a new therapeutic target for ALL treatment.

  16. Mild Developmental Foreign Accent Syndrome and Psychiatric Comorbidity: Altered White Matter Integrity in Speech and Emotion Regulation Networks.

    PubMed

    Berthier, Marcelo L; Roé-Vellvé, Núria; Moreno-Torres, Ignacio; Falcon, Carles; Thurnhofer-Hemsi, Karl; Paredes-Pacheco, José; Torres-Prioris, María J; De-Torres, Irene; Alfaro, Francisco; Gutiérrez-Cardo, Antonio L; Baquero, Miquel; Ruiz-Cruces, Rafael; Dávila, Guadalupe

    2016-01-01

    Foreign accent syndrome (FAS) is a speech disorder that is defined by the emergence of a peculiar manner of articulation and intonation which is perceived as foreign. In most cases of acquired FAS (AFAS) the new accent is secondary to small focal lesions involving components of the bilaterally distributed neural network for speech production. In the past few years FAS has also been described in different psychiatric conditions (conversion disorder, bipolar disorder, and schizophrenia) as well as in developmental disorders (specific language impairment, apraxia of speech). In the present study, two adult males, one with atypical phonetic production and the other one with cluttering, reported having developmental FAS (DFAS) since their adolescence. Perceptual analysis by naïve judges could not confirm the presence of foreign accent, possibly due to the mildness of the speech disorder. However, detailed linguistic analysis provided evidence of prosodic and segmental errors previously reported in AFAS cases. Cognitive testing showed reduced communication in activities of daily living and mild deficits related to psychiatric disorders. Psychiatric evaluation revealed long-lasting internalizing disorders (neuroticism, anxiety, obsessive-compulsive disorder, social phobia, depression, alexithymia, hopelessness, and apathy) in both subjects. Diffusion tensor imaging (DTI) data from each subject with DFAS were compared with data from a group of 21 age- and gender-matched healthy control subjects. Diffusion parameters (MD, AD, and RD) in predefined regions of interest showed changes of white matter microstructure in regions previously related with AFAS and psychiatric disorders. In conclusion, the present findings militate against the possibility that these two subjects have FAS of psychogenic origin. Rather, our findings provide evidence that mild DFAS occurring in the context of subtle, yet persistent, developmental speech disorders may be associated with structural brain

  17. Mild Developmental Foreign Accent Syndrome and Psychiatric Comorbidity: Altered White Matter Integrity in Speech and Emotion Regulation Networks

    PubMed Central

    Berthier, Marcelo L.; Roé-Vellvé, Núria; Moreno-Torres, Ignacio; Falcon, Carles; Thurnhofer-Hemsi, Karl; Paredes-Pacheco, José; Torres-Prioris, María J.; De-Torres, Irene; Alfaro, Francisco; Gutiérrez-Cardo, Antonio L.; Baquero, Miquel; Ruiz-Cruces, Rafael; Dávila, Guadalupe

    2016-01-01

    Foreign accent syndrome (FAS) is a speech disorder that is defined by the emergence of a peculiar manner of articulation and intonation which is perceived as foreign. In most cases of acquired FAS (AFAS) the new accent is secondary to small focal lesions involving components of the bilaterally distributed neural network for speech production. In the past few years FAS has also been described in different psychiatric conditions (conversion disorder, bipolar disorder, and schizophrenia) as well as in developmental disorders (specific language impairment, apraxia of speech). In the present study, two adult males, one with atypical phonetic production and the other one with cluttering, reported having developmental FAS (DFAS) since their adolescence. Perceptual analysis by naïve judges could not confirm the presence of foreign accent, possibly due to the mildness of the speech disorder. However, detailed linguistic analysis provided evidence of prosodic and segmental errors previously reported in AFAS cases. Cognitive testing showed reduced communication in activities of daily living and mild deficits related to psychiatric disorders. Psychiatric evaluation revealed long-lasting internalizing disorders (neuroticism, anxiety, obsessive-compulsive disorder, social phobia, depression, alexithymia, hopelessness, and apathy) in both subjects. Diffusion tensor imaging (DTI) data from each subject with DFAS were compared with data from a group of 21 age- and gender-matched healthy control subjects. Diffusion parameters (MD, AD, and RD) in predefined regions of interest showed changes of white matter microstructure in regions previously related with AFAS and psychiatric disorders. In conclusion, the present findings militate against the possibility that these two subjects have FAS of psychogenic origin. Rather, our findings provide evidence that mild DFAS occurring in the context of subtle, yet persistent, developmental speech disorders may be associated with structural brain

  18. Developmental Regulation and Induction of Cytochrome P450 2W1, an Enzyme Expressed in Colon Tumors

    PubMed Central

    Choong, Eva; Guo, Jia; Persson, Anna; Virding, Susanne; Johansson, Inger; Mkrtchian, Souren; Ingelman-Sundberg, Magnus

    2015-01-01

    Cytochrome P450 2W1 (CYP2W1) is expressed predominantly in colorectal and also in hepatic tumors, whereas the levels are insignificant in the corresponding normal human adult tissues. CYP2W1 has been proposed as an attractive target for colorectal cancer (CRC) therapy by exploiting its ability to activate duocarmycin prodrugs to cytotoxic metabolites. However, its endogenous function, regulation and developmental pattern of expression remain unexplored. Here we report the CYP2W1 developmental expression in the murine and human gastrointestinal tissues. The gene expression in the colon and small intestine commence at early stages of embryonic life and is completely silenced shortly after the birth. Immunohistochemical analysis of human fetal colon revealed that CYP2W1 expression is restricted to the crypt cells. The silencing of CYP2W1 after birth correlates with the increased methylation of CpG-rich regions in both murine and human CYP2W1 genes. Analysis of CYP2W1 expression in the colon adenocarcinoma cell line HCC2998 revealed that the gene expression can be induced by e.g. the antitumor agent imatinib, linoleic acid and its derivatives. The imatinib mediated induction of CYP2W1 suggests an adjuvant therapy to treatment with duocarmycins that thus would involve induction of tumor CYP2W1 levels followed by the CYP2W1 activated duocarmycin prodrugs. Taken together these data strongly support further exploration of CYP2W1 as a specific drug target in CRC. PMID:25844926

  19. Developmental Functions of miR156-Regulated SQUAMOSA PROMOTER BINDING PROTEIN-LIKE (SPL) Genes in Arabidopsis thaliana

    PubMed Central

    Hu, Tieqiang; Park, Mee-Yeon; Earley, Keith W.; Wu, Gang; Yang, Li

    2016-01-01

    Correct developmental timing is essential for plant fitness and reproductive success. Two important transitions in shoot development—the juvenile-to-adult vegetative transition and the vegetative-to-reproductive transition—are mediated by a group of genes targeted by miR156, SQUAMOSA PROMOTER BINDING PROTEIN (SBP) genes. To determine the developmental functions of these genes in Arabidopsis thaliana, we characterized their expression patterns, and their gain-of-function and loss-of-function phenotypes. Our results reveal that SBP-LIKE (SPL) genes in Arabidopsis can be divided into three functionally distinct groups: 1) SPL2, SPL9, SPL10, SPL11, SPL13 and SPL15 contribute to both the juvenile-to-adult vegetative transition and the vegetative-to-reproductive transition, with SPL9, SP13 and SPL15 being more important for these processes than SPL2, SPL10 and SPL11; 2) SPL3, SPL4 and SPL5 do not play a major role in vegetative phase change or floral induction, but promote the floral meristem identity transition; 3) SPL6 does not have a major function in shoot morphogenesis, but may be important for certain physiological processes. We also found that miR156-regulated SPL genes repress adventitious root development, providing an explanation for the observation that the capacity for adventitious root production declines as the shoot ages. miR156 is expressed at very high levels in young seedlings, and declines in abundance as the shoot develops. It completely blocks the expression of its SPL targets in the first two leaves of the rosette, and represses these genes to different degrees at later stages of development, primarily by promoting their translational repression. These results provide a framework for future studies of this multifunctional family of transcription factors, and offer new insights into the role of miR156 in Arabidopsis development. PMID:27541584

  20. Identification of a novel microtubule binding and assembly domain in the developmentally regulated inter-repeat region of tau

    PubMed Central

    1994-01-01

    Tau is a developmentally regulated microtubule-associated protein that influences microtubule behavior by directly associating with tubulin. The carboxyl terminus of tau contains multiple 18-amino acid repeats that bind microtubules and are separated by 13-14-amino acid inter- repeat (IR) regions previously thought to function as "linkers." Here, we have performed a high resolution deletion analysis of tau and identified the IR region located between repeats 1 and 2 (the R1-R2 IR) as a unique microtubule binding site with more than twice the binding affinity of any individual repeat. Truncation analyses and site- directed mutagenesis reveal that the binding activity of this site is derived primarily from lys265 and lys272, with a lesser contribution from lys271. These results predict strong, discrete electrostatic interactions between the R1-R2 IR and tubulin, in contrast to the distributed array of weak interactions thought to underlie the association between 18-amino acid repeats and microtubules (Butner, K. A., and M. W. Kirschner. J. Cell Biol. 115:717-730). Moreover, competition assays suggest that the R1-R2 IR associates with microtubules at tubulin site(s) distinct from those bound by the repeats. Finally, a synthetic peptide corresponding to just 10 amino acids of the R1-R2 IR is sufficient to promote tubulin polymerization in a sequence-dependent manner. Since the R1-R2 IR is specifically expressed in adult tau, its action may underlie some of the developmental transitions observed in neuronal microtubule organization. We suggest that the R1-R2 IR may establish an adult- specific, high affinity anchor that tethers the otherwise mobile tau molecule to the tubulin lattice, thereby increasing microtubule stability. Moreover, the absence of R1-R2 IR expression during early development may allow for the cytoskeletal plasticity required of immature neurons. PMID:8120098

  1. Identification of a novel microtubule binding and assembly domain in the developmentally regulated inter-repeat region of tau.

    PubMed

    Goode, B L; Feinstein, S C

    1994-03-01

    Tau is a developmentally regulated microtubule-associated protein that influences microtubule behavior by directly associating with tubulin. The carboxyl terminus of tau contains multiple 18-amino acid repeats that bind microtubules and are separated by 13-14-amino acid inter-repeat (IR) regions previously thought to function as "linkers." Here, we have performed a high resolution deletion analysis of tau and identified the IR region located between repeats 1 and 2 (the R1-R2 IR) as a unique microtubule binding site with more than twice the binding affinity of any individual repeat. Truncation analyses and site-directed mutagenesis reveal that the binding activity of this site is derived primarily from lys265 and lys272, with a lesser contribution from lys271. These results predict strong, discrete electrostatic interactions between the R1-R2 IR and tubulin, in contrast to the distributed array of weak interactions thought to underlie the association between 18-amino acid repeats and microtubules (Butner, K. A., and M. W. Kirschner. J. Cell Biol. 115:717-730). Moreover, competition assays suggest that the R1-R2 IR associates with microtubules at tubulin site(s) distinct from those bound by the repeats. Finally, a synthetic peptide corresponding to just 10 amino acids of the R1-R2 IR is sufficient to promote tubulin polymerization in a sequence-dependent manner. Since the R1-R2 IR is specifically expressed in adult tau, its action may underlie some of the developmental transitions observed in neuronal microtubule organization. We suggest that the R1-R2 IR may establish an adult-specific, high affinity anchor that tethers the otherwise mobile tau molecule to the tubulin lattice, thereby increasing microtubule stability. Moreover, the absence of R1-R2 IR expression during early development may allow for the cytoskeletal plasticity required of immature neurons.

  2. Molecular regulation of galectin-3 expression and therapeutic implication in cancer progression.

    PubMed

    Wang, Lei; Guo, Xiu-Li

    2016-03-01

    Galectin-3, a multifunctional protein, distributes inside and outside cells and plays an important role in tumor cell adhesion, proliferation, differentiation, angiogenesis, and metastasis in multiple tumors. Changes in galectin-3 expression are commonly seen in cancer and pre-cancerous conditions. Therefore, to understand the molecular regulation of galectin-3 expression could aid the development of new approach for cancer treatment. This review summarizes different expression of galectin-3 in cancer cells and patients' serum, the regulation mechanism and the potential therapeutic targets of galectin-3 in cancer progression.

  3. Autonomous regulation of sex-specific developmental programming in mouse fetal germ cells.

    PubMed

    Iwahashi, Kazuhiro; Yoshioka, Hirotaka; Low, Eleanor W; McCarrey, John R; Yanagimachi, Ryuzo; Yamazaki, Yukiko

    2007-10-01

    In mice, unique events regulating epigenetic programming (e.g., genomic imprinting) and replication state (mitosis versus meiosis) occur during fetal germ cell development. To determine whether these processes are autonomously programmed in fetal germ cells or are dependent upon ongoing instructive interactions with surrounding gonadal somatic cells, we isolated male and female germ cells at 13.5 days postcoitum (dpc) and maintained them in culture for 6 days, either alone or in the presence of feeder cells or gonadal somatic cells. We examined allele-specific DNA methylation in the imprinted H19 and Snrpn genes, and we also determined whether these cells remained mitotic or entered meiosis. Our results show that isolated male germ cells are able to establish a characteristic "paternal" methylation pattern at imprinted genes in the absence of any support from somatic cells. On the other hand, cultured female germ cells maintain a hypomethylated status at these loci, characteristic of the normal "maternal" methylation pattern in endogenous female germ cells before birth. Further, the surviving female germ cells entered first meiotic prophase and reached the pachytene stage, whereas male germ cells entered mitotic arrest. These results indicate that mechanisms controlling both epigenetic programming and replication state are autonomously regulated in fetal germ cells that have been exposed to the genital ridge prior to 13.5 dpc.

  4. Developmentally regulated cleavage of tRNAs in the bacterium Streptomyces coelicolor

    PubMed Central

    Haiser, Henry J.; Karginov, Fedor V.; Hannon, Gregory J.; Elliot, Marie A.

    2008-01-01

    The ability to sense and respond to environmental and physiological signals is critical for the survival of the soil-dwelling Gram-positive bacterium Streptomyces coelicolor. Nutrient deprivation triggers the onset of a complex morphological differentiation process that involves the raising of aerial hyphae and formation of spore chains, and coincides with the production of a diverse array of clinically relevant antibiotics and other secondary metabolites. These processes are tightly regulated; however, the genes and signals involved have not been fully elucidated. Here, we report a novel tRNA cleavage event that follows the same temporal regulation as morphological and physiological differentiation, and is growth medium dependent. All tRNAs appear to be susceptible to cleavage; however, there appears to be a bias towards increased cleavage of those tRNAs that specify highly utilized codons. In contrast to what has been observed in eukaryotes, accumulation of tRNA halves in S. coelicolor is not significantly affected by amino acid starvation, and is also not affected by induction of the stringent response or inhibition of ribosome function. Mutants defective in aerial development and antibiotic production exhibit altered tRNA cleavage profiles relative to wild-type strains. PMID:18084030

  5. Role of primary afferents in the developmental regulation of motor axon synapse numbers on Renshaw cells.

    PubMed

    Siembab, Valerie C; Gomez-Perez, Laura; Rotterman, Travis M; Shneider, Neil A; Alvarez, Francisco J

    2016-06-15

    Motor function in mammalian species depends on the maturation of spinal circuits formed by a large variety of interneurons that regulate motoneuron firing and motor output. Interneuron activity is in turn modulated by the organization of their synaptic inputs, but the principles governing the development of specific synaptic architectures unique to each premotor interneuron are unknown. For example, Renshaw cells receive, at least in the neonate, convergent inputs from sensory afferents (likely Ia) and motor axons, raising the question of whether they interact during Renshaw cell development. In other well-studied neurons, such as Purkinje cells, heterosynaptic competition between inputs from different sources shapes synaptic organization. To examine the possibility that sensory afferents modulate synaptic maturation on developing Renshaw cells, we used three animal models in which afferent inputs in the ventral horn are dramatically reduced (ER81(-/-) knockout), weakened (Egr3(-/-) knockout), or strengthened (mlcNT3(+/-) transgenic). We demonstrate that increasing the strength of sensory inputs on Renshaw cells prevents their deselection and reduces motor axon synaptic density, and, in contrast, absent or diminished sensory afferent inputs correlate with increased densities of motor axons synapses. No effects were observed on other glutamatergic inputs. We conclude that the early strength of Ia synapses influences their maintenance or weakening during later development and that heterosynaptic influences from sensory synapses during early development regulates the density and organization of motor inputs on mature Renshaw cells.

  6. Caudal, a key developmental regulator, is a DPE-specific transcriptional factor.

    PubMed

    Juven-Gershon, Tamar; Hsu, Jer-Yuan; Kadonaga, James T

    2008-10-15

    The regulation of gene transcription is critical for the proper development and growth of an organism. The transcription of protein-coding genes initiates at the RNA polymerase II core promoter, which is a diverse module that can be controlled by many different elements such as the TATA box and downstream core promoter element (DPE). To understand the basis for core promoter diversity, we explored potential biological functions of the DPE. We found that nearly all of the Drosophila homeotic (Hox) gene promoters, which lack TATA-box elements, contain functionally important DPE motifs that are conserved from Drosophila melanogaster to Drosophila virilis. We then discovered that Caudal, a sequence-specific transcription factor and key regulator of the Hox gene network, activates transcription with a distinct preference for the DPE relative to the TATA box. The specificity of Caudal activation for the DPE is particularly striking when a BRE(u) core promoter motif is associated with the TATA box. These findings show that Caudal is a DPE-specific activator and exemplify how core promoter diversity can be used to establish complex regulatory networks.

  7. SON controls cell-cycle progression by coordinated regulation of RNA splicing.

    PubMed

    Ahn, Eun-Young; DeKelver, Russell C; Lo, Miao-Chia; Nguyen, Tuyet Ann; Matsuura, Shinobu; Boyapati, Anita; Pandit, Shatakshi; Fu, Xiang-Dong; Zhang, Dong-Er

    2011-04-22

    It has been suspected that cell-cycle progression might be functionally coupled with RNA processing. However, little is known about the role of the precise splicing control in cell-cycle progression. Here, we report that SON, a large Ser/Arg (SR)-related protein, is a splicing cofactor contributing to efficient splicing of cell-cycle regulators. Downregulation of SON leads to severe impairment of spindle pole separation, microtubule dynamics, and genome integrity. These molecular defects result from inadequate RNA splicing of a specific set of cell-cycle-related genes that possess weak splice sites. Furthermore, we show that SON facilitates the interaction of SR proteins with RNA polymerase II and other key spliceosome components, suggesting its function in efficient cotranscriptional RNA processing. These results reveal a mechanism for controlling cell-cycle progression through SON-dependent constitutive splicing at suboptimal splice sites, with strong implications for its role in cancer and other human diseases.

  8. LSD1 is essential for oocyte meiotic progression by regulating CDC25B expression in mice

    PubMed Central

    Kim, Jeesun; Singh, Anup Kumar; Takata, Yoko; Lin, Kevin; Shen, Jianjun; Lu, Yue; Kerenyi, Marc A.; Orkin, Stuart H.; Chen, Taiping

    2015-01-01

    Mammalian oocytes are arrested at prophase I until puberty when hormonal signals induce the resumption of meiosis I and progression to meiosis II. Meiotic progression is controlled by CDK1 activity and is accompanied by dynamic epigenetic changes. Although the signalling pathways regulating CDK1 activity are well defined, the functional significance of epigenetic changes remains largely unknown. Here we show that LSD1, a lysine demethylase, regulates histone H3 lysine 4 di-methylation (H3K4me2) in mouse oocytes and is essential for meiotic progression. Conditional deletion of Lsd1 in growing oocytes results in precocious resumption of meiosis and spindle and chromosomal abnormalities. Consequently, most Lsd1-null oocytes fail to complete meiosis I and undergo apoptosis. Mechanistically, upregulation of CDC25B, a phosphatase that activates CDK1, is responsible for precocious meiotic resumption and also contributes to subsequent spindle and chromosomal defects. Our findings uncover a functional link between LSD1 and the major signalling pathway governing meiotic progression. PMID:26626423

  9. LSD1 is essential for oocyte meiotic progression by regulating CDC25B expression in mice.

    PubMed

    Kim, Jeesun; Singh, Anup Kumar; Takata, Yoko; Lin, Kevin; Shen, Jianjun; Lu, Yue; Kerenyi, Marc A; Orkin, Stuart H; Chen, Taiping

    2015-12-02

    Mammalian oocytes are arrested at prophase I until puberty when hormonal signals induce the resumption of meiosis I and progression to meiosis II. Meiotic progression is controlled by CDK1 activity and is accompanied by dynamic epigenetic changes. Although the signalling pathways regulating CDK1 activity are well defined, the functional significance of epigenetic changes remains largely unknown. Here we show that LSD1, a lysine demethylase, regulates histone H3 lysine 4 di-methylation (H3K4me2) in mouse oocytes and is essential for meiotic progression. Conditional deletion of Lsd1 in growing oocytes results in precocious resumption of meiosis and spindle and chromosomal abnormalities. Consequently, most Lsd1-null oocytes fail to complete meiosis I and undergo apoptosis. Mechanistically, upregulation of CDC25B, a phosphatase that activates CDK1, is responsible for precocious meiotic resumption and also contributes to subsequent spindle and chromosomal defects. Our findings uncover a functional link between LSD1 and the major signalling pathway governing meiotic progression.

  10. Developmentally regulated ceramide synthase 6 increases mitochondrial Ca2+ loading capacity and promotes apoptosis.

    PubMed

    Novgorodov, Sergei A; Chudakova, Daria A; Wheeler, Brian W; Bielawski, Jacek; Kindy, Mark S; Obeid, Lina M; Gudz, Tatyana I

    2011-02-11

    Ceramides, which are membrane sphingolipids and key mediators of cell-stress responses, are generated by a family of (dihydro) ceramide synthases (Lass1-6/CerS1-6). Here, we report that brain development features significant increases in sphingomyelin, sphingosine, and most ceramide species. In contrast, C(16:0)-ceramide was gradually reduced and CerS6 was down-regulated in mitochondria, thereby implicating CerS6 as a primary ceramide synthase generating C(16:0)-ceramide. Investigations into the role of CerS6 in mitochondria revealed that ceramide synthase down-regulation is associated with dramatically decreased mitochondrial Ca(2+)-loading capacity, which could be rescued by addition of ceramide. Selective CerS6 complexing with the inner membrane component of the mitochondrial permeability transition pore was detected by immunoprecipitation. This suggests that CerS6-generated ceramide could prevent mitochondrial permeability transition pore opening, leading to increased Ca(2+) accumulation in the mitochondrial matrix. We examined the effect of high CerS6 expression on cell survival in primary oligodendrocyte (OL) precursor cells, which undergo apoptotic cell death during early postnatal brain development. Exposure of OLs to glutamate resulted in apoptosis that was prevented by inhibitors of de novo ceramide biosynthesis, myriocin and fumonisin B1. Knockdown of CerS6 with siRNA reduced glutamate-triggered OL apoptosis, whereas knockdown of CerS5 had no effect: the pro-apoptotic role of CerS6 was not stimulus-specific. Knockdown of CerS6 with siRNA improved cell survival in response to nerve growth factor-induced OL apoptosis. Also, blocking mitochondrial Ca(2+) uptake or decreasing Ca(2+)-dependent protease calpain activity with specific inhibitors prevented OL apoptosis. Finally, knocking down CerS6 decreased calpain activation. Thus, our data suggest a novel role for CerS6 in the regulation of both mitochondrial Ca(2+) homeostasis and calpain, which appears to

  11. Deciphering RNA Regulatory Elements Involved in the Developmental and Environmental Gene Regulation of Trypanosoma brucei.

    PubMed

    Gazestani, Vahid H; Salavati, Reza

    2015-01-01

    Trypanosoma brucei is a vector-borne parasite with intricate life cycle that can cause serious diseases in humans and animals. This pathogen relies on fine regulation of gene expression to respond and adapt to variable environments, with implications in transmission and infectivity. However, the involved regulatory elements and their mechanisms of actions are largely unknown. Here, benefiting from a new graph-based approach for finding functional regulatory elements in RNA (GRAFFER), we have predicted 88 new RNA regulatory elements that are potentially involved in the gene regulatory network of T. brucei. We show that many of these newly predicted elements are responsive to both transcriptomic and proteomic changes during the life cycle of the parasite. Moreover, we found that 11 of predicted elements strikingly resemble previously identified regulatory elements for the parasite. Additionally, comparison with previously predicted motifs on T. brucei suggested the superior performance of our approach based on the current limited knowledge of regulatory elements in T. brucei.

  12. Regulator of G protein signaling 2 (RGS2) deficiency accelerates the progression of kidney fibrosis.

    PubMed

    Jang, Hee-Seong; Kim, Jee In; Noh, Mira; Rhee, Man Hee; Park, Kwon Moo

    2014-09-01

    The regulator of G protein signaling 2 (RGS2) is a potent negative regulator of Gq protein signals including the angiotensin II (AngII)/AngII receptor signal, which plays a critical role in the progression of fibrosis. However, the role of RGS2 on the progression of kidney fibrosis has not been assessed. Here, we investigated the role of RGS2 in kidney fibrosis induced by unilateral ureteral obstruction (UUO) in mice. UUO resulted in increased expression of RGS2 mRNA and protein in the kidney along with increases of AngII and its type 1 receptor (AT1R) signaling and fibrosis. Furthermore, UUO increased the levels of F4/80, Ly6G, myeloperoxidase, and CXCR4 in the kidneys. RGS2 deficiency significantly enhanced these changes in the kidney. RGS2 deletion in the bone marrow-derived cells by transplanting the bone marrow of RGS2 knock-out mice into wild type mice enhanced UUO-induced kidney fibrosis. Overexpression of RGS2 in HEK293 cells, a human embryonic kidney cell line, and RAW264.7 cells, a monocyte/macrophage line, inhibited the AngII-induced activation of ERK and increase of CXCR4 expression. These findings provide the first evidence that RGS2 negatively regulates the progression of kidney fibrosis following UUO, likely by suppressing fibrogenic and inflammatory responses through the inhibition of AngII/AT1R signaling.

  13. Transcription factors regulating the progression of monocot and dicot seed development.

    PubMed

    Agarwal, Pinky; Kapoor, Sanjay; Tyagi, Akhilesh K

    2011-03-01

    Seed development in this paper has been classified into the three landmark stages of cell division, organ initiation and maturation, based on morphological changes, and the available literature. The entire process proceeds at the behest of an interplay of various specific and general transcription factors (TFs). Monocots and dicots utilize overlapping, as well as distinct, TF networks during the process of seed development. The known TFs in rice and Arabidopsis have been chronologically categorized into the three stages. The main regulators of seed development contain B3 or HAP3 domains. These interact with bZIP and AP2 TFs. Other TFs that play an indispensable role during the process contain homeobox-, NAC-, MYB-, or ARF-domains. This paper is a comprehensive analysis of the TFs essential for seed development and their interactions. An understanding of this interplay will not only help unravel an integrated developmental process, but will also pave the way for biotechnological applications.

  14. Epilepsy gene LGI1 regulates postnatal developmental remodeling of retinogeniculate synapses.

    PubMed

    Zhou, Yu-Dong; Zhang, Dawei; Ozkaynak, Ekim; Wang, Xuan; Kasper, Ekkehard M; Leguern, Eric; Baulac, Stéphanie; Anderson, Matthew P

    2012-01-18

    Retinogeniculate connections undergo postnatal refinement in the developing visual system. Here we report that non-ion channel epilepsy gene LGI1 (leucine-rich glioma-inactivated), mutated in human autosomal dominant lateral temporal lobe epilepsy (ADLTE), regulates postnatal pruning of retinal axons in visual relay thalamus. By introducing an ADLTE-associated truncated mutant LGI1 (836delC) or excess full-length LGI1 into transgenic mice, we found that mutant LGI1 blocks, whereas excess LGI1 accelerates, retinogeniculate axon pruning. The normal postnatal single fiber strengthening was arrested by mutant LGI1 and, contrastingly, was enhanced by excess wild-type LGI1. The maximum response of the retinogeniculate synapses, conversely, remained the same in mature LGI1 transgenic mice, indicating that mutant LGI1 blocks, whereas excess wild-type LGI1 promotes, weak axon fiber elimination. Heterozygous deletion of the LGI1 gene, as found in ADLTE patients, inhibited postnatal retinogeniculate synapse elimination, an effect similar to the ADLTE truncated mutant LGI1. The results identify sensory axon remodeling defects in a sensory aura-associated human epilepsy disorder.

  15. Developmental epigenetic modification regulates stochastic expression of clustered protocadherin genes, generating single neuron diversity.

    PubMed

    Toyoda, Shunsuke; Kawaguchi, Masahumi; Kobayashi, Toshihiro; Tarusawa, Etsuko; Toyama, Tomoko; Okano, Masaki; Oda, Masaaki; Nakauchi, Hiromitsu; Yoshimura, Yumiko; Sanbo, Makoto; Hirabayashi, Masumi; Hirayama, Teruyoshi; Hirabayashi, Takahiro; Yagi, Takeshi

    2014-04-02

    In the brain, enormous numbers of neurons have functional individuality and distinct circuit specificities. Clustered Protocadherins (Pcdhs), diversified cell-surface proteins, are stochastically expressed by alternative promoter choice and affect dendritic arborization in individual neurons. Here we found that the Pcdh promoters are differentially methylated by the de novo DNA methyltransferase Dnmt3b during early embryogenesis. To determine this methylation's role in neurons, we produced chimeric mice from Dnmt3b-deficient induced pluripotent stem cells (iPSCs). Single-cell expression analysis revealed that individual Dnmt3b-deficient Purkinje cells expressed increased numbers of Pcdh isoforms; in vivo, they exhibited abnormal dendritic arborization. These results indicate that DNA methylation by Dnmt3b at early embryonic stages regulates the probability of expression for the stochastically expressed Pcdh isoforms. They also suggest a mechanism for a rare human recessive disease, the ICF (Immunodeficiency, Centromere instability, and Facial anomalies) syndrome, which is caused by Dnmt3b mutations.

  16. Developmental expression of the N-myc downstream regulated gene (Ndrg) family during Xenopus tropicalis embryogenesis.

    PubMed

    Zhong, Chao; Zhou, Yan-Kuan; Yang, Shan-Shan; Zhao, Jun-Fang; Zhu, Xiao-Long; Chen, Hen-Huang; Chen, Pei-Chao; Huang, Li-Quan; Huang, Xiao

    2015-01-01

    The N-myc downstream regulated gene (Ndrg) family consists of four main members Ndrg1, 2, 3, and 4. The Ndrg genes are involved in many vital biological events including development. However, comprehensive expression patterns of this gene family during vertebrate embryogenesis remain largely unknown. Here, we analyzed the Ndrg family from the evolutionary perspective and examined the expression patterns of the Ndrg genes during Xenopus tropicalis embryogenesis. Different Ndrg family members of vertebrates are separated into different homology clusters which can be further classified into two groups and each Ndrg family member is well conserved during evolution. The temporal and spatial expression patterns of Ndrg1, 2, 3 and 4 are different during early Xenopus tropicalis development. Ndrg1, 2 and 4 are maternally expressed genes while Ndrg3 is a zygotically expressed gene. The Ndrg genes are differentially expressed in the developing central nervous system, the developing sensory organs, and the developing excretory organs. Moreover, they also show other specific expression domains. Our results indicate that the Ndrg genes exhibit specific expression patterns and may play different roles during vertebrate embryogenesis.

  17. The beta 1 integrin distal promoter is developmentally regulated in transgenic mice.

    PubMed

    Hirsch, E; Balzac, F; Pastore, C; Tarone, G; Silengo, L; Altruda, F

    1993-12-01

    Transgenic mice harbouring 5' flanking sequences of the human beta 1 integrin gene linked to the Escherichia coli lacZ gene have been generated to examine spatial and temporal distribution of the promoter activity during development. Our previous data showed that this regulatory region is composed by two promoters, called distal and proximal, located closely on the human genome. To determine the role of each promoter region during development we generated transgenic mice using these two sequences linked to the lacZ reporter gene. Their analysis shows that these two sequences, as determined by in vitro studies, have different efficiencies in promoting transcription. Actually mice carrying the proximal promoter region exhibit a weak lacZ expression resulting in an undetectable beta-galactosidase activity in both embryonic and adult tissues. On the other hand, transgenic mice carrying the distal promoter express beta-galactosidase at high efficiency during embryonic development. The pattern of transgene expression is consistent with the localization of beta 1 protein on mouse embryos evidenced by immunohistochemistry. Moreover the distal promoter is subjected to a temporal modulation since in adult transgenic mice lacZ expression decreases to a level detected only by RT-PCR analysis. We have determined a similar down-regulation analysing by Northern blot beta 1 mRNA in adult and embryonic organs such as heart and gut.

  18. Suppression subtractive hybridization and comparative expression analysis to identify developmentally regulated genes in filamentous fungi.

    PubMed

    Gesing, Stefan; Schindler, Daniel; Nowrousian, Minou

    2013-09-01

    Ascomycetes differentiate four major morphological types of fruiting bodies (apothecia, perithecia, pseudothecia and cleistothecia) that are derived from an ancestral fruiting body. Thus, fruiting body differentiation is most likely controlled by a set of common core genes. One way to identify such genes is to search for genes with evolutionary conserved expression patterns. Using suppression subtractive hybridization (SSH), we selected differentially expressed transcripts in Pyronema confluens (Pezizales) by comparing two cDNA libraries specific for sexual and for vegetative development, respectively. The expression patterns of selected genes from both libraries were verified by quantitative real time PCR. Expression of several corresponding homologous genes was found to be conserved in two members of the Sordariales (Sordaria macrospora and Neurospora crassa), a derived group of ascomycetes that is only distantly related to the Pezizales. Knockout studies with N. crassa orthologues of differentially regulated genes revealed a functional role during fruiting body development for the gene NCU05079, encoding a putative MFS peptide transporter. These data indicate conserved gene expression patterns and a functional role of the corresponding genes during fruiting body development; such genes are candidates of choice for further functional analysis.

  19. MMSET is dynamically regulated during cell-cycle progression and promotes normal DNA replication

    PubMed Central

    Evans, Debra L.; Zhang, Haoxing; Ham, Hyoungjun; Pei, Huadong; Lee, SeungBaek; Kim, JungJin; Billadeau, Daniel D.; Lou, Zhenkun

    2016-01-01

    ABSTRACT The timely and precise duplication of cellular DNA is essential for maintaining genome integrity and is thus tightly-regulated. During mitosis and G1, the Origin Recognition Complex (ORC) binds to future replication origins, coordinating with multiple factors to load the minichromosome maintenance (MCM) complex onto future replication origins as part of the pre-replication complex (pre-RC). The pre-RC machinery, in turn, remains inactive until the subsequent S phase when it is required for replication fork formation, thereby initiating DNA replication. Multiple myeloma SET domain-containing protein (MMSET, a.k.a. WHSC1, NSD2) is a histone methyltransferase that is frequently overexpressed in aggressive cancers and is essential for normal human development. Several studies have suggested a role for MMSET in cell-cycle regulation; however, whether MMSET is itself regulated during cell-cycle progression has not been examined. In this study, we report that MMSET is degraded during S phase in a cullin-ring ligase 4-Cdt2 (CRL4Cdt2) and proteasome-dependent manner. Notably, we also report defects in DNA replication and a decreased association of pre-RC factors with chromatin in MMSET-depleted cells. Taken together, our results suggest a dynamic regulation of MMSET levels throughout the cell cycle, and further characterize the role of MMSET in DNA replication and cell-cycle progression. PMID:26771714

  20. MMSET is dynamically regulated during cell-cycle progression and promotes normal DNA replication.

    PubMed

    Evans, Debra L; Zhang, Haoxing; Ham, Hyoungjun; Pei, Huadong; Lee, SeungBaek; Kim, JungJin; Billadeau, Daniel D; Lou, Zhenkun

    2016-01-01

    The timely and precise duplication of cellular DNA is essential for maintaining genome integrity and is thus tightly-regulated. During mitosis and G1, the Origin Recognition Complex (ORC) binds to future replication origins, coordinating with multiple factors to load the minichromosome maintenance (MCM) complex onto future replication origins as part of the pre-replication complex (pre-RC). The pre-RC machinery, in turn, remains inactive until the subsequent S phase when it is required for replication fork formation, thereby initiating DNA replication. Multiple myeloma SET domain-containing protein (MMSET, a.k.a. WHSC1, NSD2) is a histone methyltransferase that is frequently overexpressed in aggressive cancers and is essential for normal human development. Several studies have suggested a role for MMSET in cell-cycle regulation; however, whether MMSET is itself regulated during cell-cycle progression has not been examined. In this study, we report that MMSET is degraded during S phase in a cullin-ring ligase 4-Cdt2 (CRL4(Cdt2)) and proteasome-dependent manner. Notably, we also report defects in DNA replication and a decreased association of pre-RC factors with chromatin in MMSET-depleted cells. Taken together, our results suggest a dynamic regulation of MMSET levels throughout the cell cycle, and further characterize the role of MMSET in DNA replication and cell-cycle progression.

  1. The interferon-related developmental regulator 1 is used by human papillomavirus to suppress NFκB activation

    PubMed Central

    Tummers, Bart; Goedemans, Renske; Pelascini, Laetitia P. L.; Jordanova, Ekaterina S.; van Esch, Edith M. G.; Meyers, Craig; Melief, Cornelis J. M.; Boer, Judith M.; van der Burg, Sjoerd H.

    2015-01-01

    High-risk human papillomaviruses (hrHPVs) infect keratinocytes and successfully evade host immunity despite the fact that keratinocytes are well equipped to respond to innate and adaptive immune signals. Using non-infected and freshly established or persistent hrHPV-infected keratinocytes we show that hrHPV impairs the acetylation of NFκB/RelA K310 in keratinocytes. As a consequence, keratinocytes display a decreased pro-inflammatory cytokine production and immune cell attraction in response to stimuli of the innate or adaptive immune pathways. HPV accomplishes this by augmenting the expression of interferon-related developmental regulator 1 (IFRD1) in an EGFR-dependent manner. Restoration of NFκB/RelA acetylation by IFRD1 shRNA, cetuximab treatment or the HDAC1/3 inhibitor entinostat increases basal and induced cytokine expression. Similar observations are made in IFRD1-overexpressing HPV-induced cancer cells. Thus, our study reveals an EGFR–IFRD1-mediated viral immune evasion mechanism, which can also be exploited by cancer cells. PMID:26055519

  2. Quantitative proteomics identify DAB2 as a cardiac developmental regulator that inhibits WNT/β-catenin signaling.

    PubMed

    Hofsteen, Peter; Robitaille, Aaron M; Chapman, Daniel Patrick; Moon, Randall T; Murry, Charles E

    2016-01-26

    To reveal the molecular mechanisms involved in cardiac lineage determination and differentiation, we quantified the proteome of human embryonic stem cells (hESCs), cardiac progenitor cells (CPCs), and cardiomyocytes during a time course of directed differentiation by label-free quantitative proteomics. This approach correctly identified known stage-specific markers of cardiomyocyte differentiation, including SRY-box2 (SOX2), GATA binding protein 4 (GATA4), and myosin heavy chain 6 (MYH6). This led us to determine whether our proteomic screen could reveal previously unidentified mediators of heart development. We identified Disabled 2 (DAB2) as one of the most dynamically expressed proteins in hESCs, CPCs, and cardiomyocytes. We used clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein 9 (Cas9) mutagenesis in zebrafish to assess whether DAB2 plays a functional role during cardiomyocyte differentiation. We found that deletion of Dab2 in zebrafish embryos led to a significant reduction in cardiomyocyte number and increased endogenous WNT/β-catenin signaling. Furthermore, the Dab2-deficient defects in cardiomyocyte number could be suppressed by overexpression of dickkopf 1 (DKK1), an inhibitor of WNT/β-catenin signaling. Thus, inhibition of WNT/β-catenin signaling by DAB2 is essential for establishing the correct number of cardiomyocytes in the developing heart. Our work demonstrates that quantifying the proteome of human stem cells can identify previously unknown developmental regulators.

  3. A novel microtubule-based motor protein (KIF4) for organelle transports, whose expression is regulated developmentally

    PubMed Central

    1994-01-01

    To understand the mechanisms of transport for organelles in the axon, we isolated and sequenced the cDNA encoding KIF4 from murine brain, and characterized the molecule biochemically and immunocytochemically. Complete amino acid sequence analysis of KIF4 and ultrastructural studies of KIF4 molecules expressed in Sf9 cells revealed that the protein contains 1,231 amino acid residues (M(r) 139,550) and that the molecule (116-nm rod with globular heads and tail) consists of three domains: an NH2-terminal globular motor domain, a central alpha-helical stalk domain and a COOH-terminal tail domain. KIF4 protein has the property of nucleotide-dependent binding to microtubules, microtubule- activated ATPase activity, and microtubule plus-end-directed motility. Northern blot analysis and in situ hybridization demonstrated that KIF4 is strongly expressed in juvenile tissues including differentiated young neurons, while its expression is decreased considerably in adult mice except in spleen. Immunocytochemical studies revealed that KIF4 colocalized with membranous organelles both in growth cones of differentiated neurons and in the cytoplasm of cultured fibroblasts. During mitotic phase of cell cycle, KIF4 appears to colocalize with membranous organelles in the mitotic spindle. Hence we conclude that KIF4 is a novel microtubule-associated anterograde motor protein for membranous organelles, the expression of which is regulated developmentally. PMID:7929562

  4. Developmental regulation of an snRNP core protein epitope during pig embryogenesis and after nuclear transfer for cloning.

    PubMed

    Prather, R S; Rickords, L F

    1992-10-01

    The appearance and stabilization of a core protein epitope of the snRNP is developmentally regulated during pig embryogenesis. The epitope recognized by the monoclonal antibody Y12 is present in the germinal vesicle of mature oocytes and interphase nuclei of late 4-cell stage (24 to 30 hours post cleavage to the 4-cell stage) to blastocyst stage embryos. There was no antibody localization within pronuclei, or nuclei of 2-cell or early 4-cell stage embryos. Zygotes or 2-cell stage embryos cultured in the presence of alpha-amanitin to the late 4-cell stage showed no immunoreactivity, whereas control embryos had immunoreactivity. Thus antibody localization was correlated with RNA synthesis and RNA processing that begins by 24 hours post cleavage to the 4-cell stage. A final experiment showed no detectable immunoreactivity in 16-cell stage nuclei that had been transferred to enucleated activated meiotic metaphase II oocytes. Since immunoreactivity is associated with active RNA synthesis and RNA processing, it suggests that the 16-cell stage nucleus, which is RNA synthetically active, does not process RNA after nuclear transfer to an enucleated activated meiotic metaphase II oocyte.

  5. Characterization of RBP9 and RBP10, two developmentally regulated RNA-binding proteins in Trypanosoma brucei.

    PubMed

    De Pablos, Luis Miguel; Kelly, Steve; de Freitas Nascimento, Janaina; Sunter, Jack; Carrington, Mark

    2017-04-01

    The fate of an mRNA is determined by its interaction with proteins and small RNAs within dynamic complexes called ribonucleoprotein complexes (mRNPs). In Trypanosoma brucei and related kinetoplastids, responses to internal and external signals are mainly mediated by post-transcriptional processes. Here, we used proximity-dependent biotin identification (BioID) combined with RNA-seq to investigate the changes resulting from ectopic expression of RBP10 and RBP9, two developmentally regulated RNA-binding proteins (RBPs). Both RBPs have reduced expression in insect procyclic forms (PCFs) compared with bloodstream forms (BSFs). Upon overexpression in PCFs, both proteins were recruited to cytoplasmic foci, co-localizing with the processing body marker SCD6. Further, both RBPs altered the transcriptome from a PCF- to a BSF-like pattern. Notably, upon expression of BirA*-RBP9 and BirA*-RBP10, BioID yielded more than 200 high confidence protein interactors (more than 10-fold enriched); 45 (RBP9) and 31 (RBP10) were directly related to mRNA metabolism. This study validates the use of BioID for investigating mRNP components but also illustrates the complexity of mRNP function.

  6. Developmental regulation and extracellular release of a VSG expression-site-associated gene product from Trypanosoma brucei bloodstream forms.

    PubMed

    Barnwell, Eleanor M; van Deursen, Frederick J; Jeacock, Laura; Smith, Katherine A; Maizels, Rick M; Acosta-Serrano, Alvaro; Matthews, Keith

    2010-10-01

    Trypanosomes evade host immunity by exchanging variant surface glycoprotein (VSG) coats. VSG genes are transcribed from telomeric expression sites, which contain a diverse family of expression-site-associated genes (ESAGs). We have discovered that the mRNAs for one ESAG family, ESAG9, are strongly developmentally regulated, being enriched in stumpy forms, a life-cycle stage in the mammalian bloodstream that is important for the maintenance of chronic parasite infections and for tsetse transmission. ESAG9 gene sequences are highly diverse in the genome and encode proteins with weak similarity to the massively diverse MASP proteins in Trypanosoma cruzi. We demonstrate that ESAG9 proteins are modified by N-glycosylation and can be shed to the external milieu, this being dependent upon coexpression with at least one other family member. The expression profile and extracellular release of ESAG9 proteins represents a novel and unexpected aspect of the transmission biology of trypanosomes in their mammalian host. We suggest that these molecules might interact with the external environment, with possible implications for infection chronicity or parasite transmission.

  7. The Developmentally Regulated alb1 Gene of Aspergillus fumigatus: Its Role in Modulation of Conidial Morphology and Virulence

    PubMed Central

    Tsai, Huei-Fung; Chang, Yun C.; Washburn, Ronald G.; Wheeler, Michael H.; Kwon-Chung, K. J.

    1998-01-01

    Aspergillus fumigatus, an important opportunistic pathogen which commonly affects neutropenic patients, produces conidia with a bluish-green color. We identified a gene, alb1, which is required for conidial pigmentation. The alb1 gene encodes a putative polyketide synthase, and disruption of alb1 resulted in an albino conidial phenotype. Expression of alb1 is developmentally regulated, and the 7-kb transcript is detected only during the conidiation stage. The alb1 mutation was found to block 1,3,6,8-tetrahydroxynaphthalene production, indicating that alb1 is involved in dihydroxynaphthalene-melanin biosynthesis. Scanning electron microscopy studies showed that the alb1 disruptant exhibited a smooth conidial surface, whereas complementation of the alb1 deletion restored the echinulate wild-type surface. Disruption of alb1 resulted in a significant increase in C3 binding on conidial surfaces, and the conidia of the alb1 disruptant were ingested by human neutrophils at a higher rate than were those of the wild type. The alb1-complemented strain producing bluish-green conidia exhibited inefficient C3 binding and neutrophil-mediated phagocytosis quantitatively similar to those of the wild type. Importantly, the alb1 disruptant had a statistically significant loss of virulence compared to the wild-type and alb1-complemented strains in a murine model. These results suggest that disruption of alb1 causes pleiotropic effects on conidial morphology and fungal virulence. PMID:9620950

  8. Developmental and heat stress-regulated expression of HsfA2 and small heat shock proteins in tomato anthers

    PubMed Central

    Giorno, Filomena; Wolters-Arts, Mieke; Grillo, Stefania; Scharf, Klaus-Dieter; Vriezen, Wim H.; Mariani, Celestina

    2010-01-01

    The high sensitivity of male reproductive cells to high temperatures may be due to an inadequate heat stress response. The results of a comprehensive expression analysis of HsfA2 and Hsp17-CII, two important members of the heat stress system, in the developing anthers of a heat-tolerant tomato genotype are reported here. A transcriptional analysis at different developmental anther/pollen stages was performed using semi-quantitative and real-time PCR. The messengers were localized using in situ RNA hybridization, and protein accumulation was monitored using immunoblot analysis. Based on the analysis of the gene and protein expression profiles, HsfA2 and Hsp17-CII are finely regulated during anther development and are further induced under both short and prolonged heat stress conditions. These data suggest that HsfA2 may be directly involved in the activation of protection mechanisms in the tomato anther during heat stress and, thereby, may contribute to tomato fruit set under adverse temperatures. PMID:19854799

  9. Developmental and environmental regulation of a phenylalanine ammonia-lyase-beta-glucuronidase gene fusion in transgenic tobacco plants.

    PubMed Central

    Liang, X W; Dron, M; Schmid, J; Dixon, R A; Lamb, C J

    1989-01-01

    A 1.1-kilobase promoter fragment of the bean (Phaseolus vulgaris L.) phenylalanine ammonia-lyase (EC 4.3.1.5) gene PAL2 was translationally fused to the beta-glucuronidase reporter gene and transferred to tobacco by Agrobacterium tumefaciens-mediated leaf disk transformation. The distribution of beta-glucuronidase activity in these transgenic plants is very similar to that of endogenous PAL2 transcripts in bean, with very high levels in petals; marked accumulation in anthers, stigmas, roots, and shoots; and low levels in sepals, ovaries, and leaves. Histochemical analysis of the spatial pattern of beta-glucuronidase activity showed that the PAL2 promoter is highly active in the shoot apical meristem, the zone of cell proliferation immediately adjacent to the root apical meristem, and in the early stages of vascular development at the inception of xylem differentiation. Wounding and light evoke specific changes in the spatial pattern of beta-glucuronidase activity in stems, including induction in the epidermis. These data indicate that the PAL2 promoter transduces a complex set of developmental and environmental cues into an integrated spatial and temporal program of gene expression to regulate the synthesis of a diverse array of phenylpropanoid natural products. Images PMID:2594769

  10. The neuronal ceroid lipofuscinosis Cln8 gene expression is developmentally regulated in mouse brain and up-regulated in the hippocampal kindling model of epilepsy

    PubMed Central

    Lonka, Liina; Aalto, Antti; Kopra, Outi; Kuronen, Mervi; Kokaia, Zaal; Saarma, Mart; Lehesjoki, Anna-Elina

    2005-01-01

    Background The neuronal ceroid lipofuscinoses (NCLs) are a group of inherited neurodegenerative disorders characterized by accumulation of autofluorescent material in many tissues, especially in neurons. Mutations in the CLN8 gene, encoding an endoplasmic reticulum (ER) transmembrane protein of unknown function, underlie NCL phenotypes in humans and mice. The human phenotype is characterized by epilepsy, progressive psychomotor deterioration and visual loss, while motor neuron degeneration (mnd) mice with a Cln8 mutation show progressive motor neuron dysfunction and retinal degeneration. Results We investigated spatial and temporal expression of Cln8 messenger ribonucleic acid (mRNA) using in situ hybridization, reverse transcriptase polymerase chain reaction (RT-PCR) and northern blotting. Cln8 is ubiquitously expressed at low levels in embryonic and adult tissues. In prenatal embryos Cln8 is most prominently expressed in the developing gastrointestinal tract, dorsal root ganglia (DRG) and brain. In postnatal brain the highest expression is in the cortex and hippocampus. Expression of Cln8 mRNA in the central nervous system (CNS) was also analyzed in the hippocampal electrical kindling model of epilepsy, in which Cln8 expression was rapidly up-regulated in hippocampal pyramidal and granular neurons. Conclusion Expression of Cln8 in the developing and mature brain suggests roles for Cln8 in maturation, differentiation and supporting the survival of different neuronal populations. The relevance of Cln8 up-regulation in hippocampal neurons of kindled mice should be further explored. PMID:15826318

  11. Developmental regulation of the late phase of long-term potentiation (L-LTP) and metaplasticity in hippocampal area CA1 of the rat

    PubMed Central

    Cao, Guan

    2012-01-01

    Long-term potentiation (LTP) is a form of synaptic plasticity thought to underlie memory; thus knowing its developmental profile is fundamental to understanding function. Like memory, LTP has multiple phases with distinct timing and mechanisms. The late phase of LTP (L-LTP), lasting longer than 3 h, is protein synthesis dependent and involves changes in the structure and content of dendritic spines, the major sites of excitatory synapses. In previous work, tetanic stimulation first produced L-LTP at postnatal day 15 (P15) in area CA1 of rat hippocampus. Here we used a more robust induction paradigm involving theta-burst stimulation (TBS) in acute slices and found the developmental onset of L-LTP to be 3 days earlier at P12. In contrast, at P8–11, TBS only reversed the synaptic depression that occurs from test-pulse stimulation in developing (P8–15) hippocampus. A second bout of TBS delivered 30–180 min later produced L-LTP at P10–11 but not at P8–9 and enhanced L-LTP at P12–15. Both the developmental onset and the enhanced L-LTP produced by repeated bouts of TBS were blocked by the N-methyl-d-aspartate receptor antagonist dl-2-amino-5-phosphonovaleric acid. Thus the developmental onset age is P12 for L-LTP induced by the more robust and perhaps more naturalistic TBS induction paradigm. Metaplasticity produced by repeated bouts of TBS is developmentally regulated, advancing the capacity for L-LTP from P12 to P10, but not to younger ages. Together these findings provide a new basis from which to investigate mechanisms that regulate the developmental onset of this important form of synaptic plasticity. PMID:22114158

  12. Developmental regulation of glucogenesis in the sheep fetus during late gestation.

    PubMed

    Fowden, A L; Mundy, L; Silver, M

    1998-05-01

    1. Using tracer methodology, endogenous glucose production was measured in twenty-six chronically catheterized sheep fetuses during normal fed conditions and in response to a 48 h period of maternal fasting at different gestational ages during the last 10-15 days of gestation (term, 145 +/- 2 days). 2. In normal fed conditions, the rate of fetal glucose production was negligible until 143-145 days when it rose significantly to account for 50 % of the glucose used by the fetus. The rise in fetal glucogenesis towards term closely parallelled the normal prepartum rise in fetal plasma cortisol and catecholamines. 3. Maternal fasting for 48 h induced endogenous glucose production in fetuses at 139-141 days but not at 133-135 days of gestation. Maternal fasting also induced increases in the plasma cortisol and noradrenaline levels in all the fetuses studied. Fetal plasma cortisol levels at the end of the fast and the increment in fetal plasma cortisol during maternal fasting were significantly greater in the older groups of fasted animals. 4. When the data from all the fetuses were combined, partial correlation analysis of fetal glucose production and the log plasma concentrations of cortisol and total catecholamines showed that plasma cortisol was the predominant regulator of fetal glucogenesis during late gestation. However, once plasma cortisol levels exceeded 17.5 ng ml-1, plasma catecholamines were a major influence on fetal glucogenesis. 5. The results show that glucogenesis occurs in fetal sheep during late gestation in conditions in which the fetal plasma concentrations of cortisol and catecholamines are elevated. They also suggest that cortisol enhances the capacity for glucogenesis in utero, while catecholamines actually activate glucose production in sheep fetuses close to term.

  13. Alternate transcripts of a floral developmental regulator have both distinct and redundant functions in opium poppy

    PubMed Central

    Hands, Philip; Vosnakis, Nikolaos; Betts, Donna; Irish, Vivian F.; Drea, Sinéad

    2011-01-01

    Background and Aims The MADS-box transcription factor AGAMOUS (AG) is an important regulator of stamen and fruit identity as well as floral meristem determinacy in a number of core eudicots and monocots. However, its role outside of these groups has not been assessed explicitly. Examining its role in opium poppy, a basal eudicot, could uncover much about the evolution and development of flower and fruit development in the angiosperms. Methods AG orthologues were isolated by degenerate RT-PCR and the gene sequence and structure examined; gene expression was characterized using in situ hybridization and the function assessed using virus-induced gene silencing. Key Results In opium poppy, a basal eudicot, the AGAMOUS orthologue is alternatively spliced to produce encoded products that vary at the C-terminus, termed PapsAG-1 and PapsAG-2. Both transcripts are expressed at high levels in stamens and carpels. The functional implications of this alternative transcription were examined using virus-induced gene silencing and the results show that PapsAG-1 has roles in stamen and carpel identity, reflecting those found for Arabidopsis AG. In contrast, PapsAG-2, while displaying redundancy in these functions, has a distinctive role in aspects of carpel development reflected in septae, ovule and stigma defects seen in the loss-of-function line generated. Conclusions These results describe the first explicit functional analysis of an AG-clade gene in a basal eudicot; illustrate one of the few examples of the functional consequences of alternative splicing in transcription factors and reveal the importance of alternative transcription, as well as gene duplication, as a driving force in evolution. PMID:21385783

  14. Postnatal developmental expression of regulator of G protein signaling 14 (RGS14) in the mouse brain.

    PubMed

    Evans, Paul R; Lee, Sarah E; Smith, Yoland; Hepler, John R

    2014-01-01

    Regulator of G protein signaling 14 (RGS14) is a multifunctional scaffolding protein that integrates G protein and mitogen-activated protein kinase (MAPK) signaling pathways. In the adult mouse brain, RGS14 mRNA and protein are found almost exclusively in hippocampal CA2 neurons. We have shown that RGS14 is a natural suppressor of CA2 synaptic plasticity and hippocampal-dependent learning and memory. However, the protein distribution and spatiotemporal expression patterns of RGS14 in mouse brain during postnatal development are unknown. Here, using a newly characterized monoclonal anti-RGS14 antibody, we demonstrate that RGS14 protein immunoreactivity is undetectable at birth (P0), with very low mRNA expression in the brain. However, RGS14 protein and mRNA are upregulated during early postnatal development, with protein first detected at P7, and both increasing over time until reaching highest sustained levels throughout adulthood. Our immunoperoxidase data demonstrate that RGS14 protein is expressed in regions outside of hippocampal CA2 during development including the primary olfactory areas, the anterior olfactory nucleus and piriform cortex, and the olfactory associated orbital and entorhinal cortices. RGS14 is also transiently expressed in neocortical layers II/III and V during postnatal development. Finally, we show that RGS14 protein is first detected in the hippocampus at P7, with strongest immunoreactivity in CA2 and fasciola cinerea and sporadic immunoreactivity in CA1; labeling intensity in hippocampus increases until adulthood. These results show that RGS14 mRNA and protein are upregulated throughout postnatal mouse development, and RGS14 protein exhibits a dynamic localization pattern that is enriched in hippocampus and primary olfactory cortex in the adult mouse brain.

  15. Transcriptome Sequencing and Developmental Regulation of Gene Expression in Anopheles aquasalis

    PubMed Central

    Silva, Maria C. P.; Lopes, Adriana R.; Barros, Michele S.; Sá-Nunes, Anderson; Kojin, Bianca B.; Carvalho, Eneas; Suesdek, Lincoln; Silva-Neto, Mário Alberto C.; James, Anthony A.; Capurro, Margareth L.

    2014-01-01

    Background Anopheles aquasalis is a major malaria vector in coastal areas of South and Central America where it breeds preferentially in brackish water. This species is very susceptible to Plasmodium vivax and it has been already incriminated as responsible vector in malaria outbreaks. There has been no high-throughput investigation into the sequencing of An. aquasalis genes, transcripts and proteins despite its epidemiological relevance. Here we describe the sequencing, assembly and annotation of the An. aquasalis transcriptome. Methodology/Principal Findings A total of 419 thousand cDNA sequence reads, encompassing 164 million nucleotides, were assembled in 7544 contigs of ≥2 sequences, and 1999 singletons. The majority of the An. aquasalis transcripts encode proteins with their closest counterparts in another neotropical malaria vector, An. darlingi. Several analyses in different protein databases were used to annotate and predict the putative functions of the deduced An. aquasalis proteins. Larval and adult-specific transcripts were represented by 121 and 424 contig sequences, respectively. Fifty-one transcripts were only detected in blood-fed females. The data also reveal a list of transcripts up- or down-regulated in adult females after a blood meal. Transcripts associated with immunity, signaling networks and blood feeding and digestion are discussed. Conclusions/Significance This study represents the first large-scale effort to sequence the transcriptome of An. aquasalis. It provides valuable information that will facilitate studies on the biology of this species and may lead to novel strategies to reduce malaria transmission on the South American continent. The An. aquasalis transcriptome is accessible at http://exon.niaid.nih.gov/transcriptome/An_aquasalis/Anaquexcel.xlsx. PMID:25033462

  16. Intra-Testicular Signals Regulate Germ Cell Progression and Production of Qualitatively Mature Spermatozoa in Vertebrates

    PubMed Central

    Meccariello, Rosaria; Chianese, Rosanna; Chioccarelli, Teresa; Ciaramella, Vincenza; Fasano, Silvia; Pierantoni, Riccardo; Cobellis, Gilda

    2014-01-01

    Spermatogenesis, a highly conserved process in vertebrates, is mainly under the hypothalamic–pituitary control, being regulated by the secretion of pituitary gonadotropins, follicle stimulating hormone, and luteinizing hormone, in response to stimulation exerted by gonadotropin releasing hormone from hypothalamic neurons. At testicular level, gonadotropins bind specific receptors located on the somatic cells regulating the production of steroids and factors necessary to ensure a correct spermatogenesis. Indeed, besides the endocrine route, a complex network of cell-to-cell communications regulates germ cell progression, and a combination of endocrine and intra-gonadal signals sustains the production of high quality mature spermatozoa. In this review, we focus on the recent advances in the area of the intra-gonadal signals supporting sperm development. PMID:24847312

  17. Deciphering the spatio-temporal regulation of entry and progression through mitosis.

    PubMed

    Gheghiani, Lilia; Gavet, Olivier

    2014-02-01

    Mitosis has been studied since the early 1880s as a key event of the cell division cycle where remarkable changes in cellular architecture take place and ultimately lead to an equal segregation of duplicated chromosomes into two daughter cells. A detailed description of the complex and highly ordered cellular events taking place is now available. Many regulators involved in key steps including entry into mitosis, nuclear envelope breakdown, microtubule (MT) spindle formation, and chromosome attachment, as well as mitotic exit and cytokinesis, have also been identified. However, understanding the precise spatio-temporal contribution of each regulator in the cell reorganization process has been technically challenging. This review will focus on a number of recent advances in our understanding of the spatial distribution of protein activities and the temporal regulation of their activation and inactivation during entry and progression through mitosis by the use of intramolecular Förster resonance energy transfer (FRET)-based biosensors.

  18. Developmental expression, differential hormonal regulation and evolution of thyroid and glucocorticoid receptor variants in a marine acanthomorph teleost (Sciaenops ocellatus).

    PubMed

    Applebaum, Scott L; Finn, Roderick Nigel; Faulk, Cynthia K; Joan Holt, G; Scott Nunez, B

    2012-03-01

    Interactions between the thyroid hormone (TH) and corticosteroid (CS) hormone axes are suggested to regulate developmental processes in vertebrates with a larval phase. To investigate this hypothesis, we isolated three nuclear receptors from a larval acanthomorph teleost, the red drum (Sciaenops ocellatus), and established their orthologies as thraa, thrb-L and gra-L using phylogenomic and functional analyses. Functional characterization of the TH receptors in COS-1 cells revealed that Thraa and Thrb-L exhibit dose-dependent transactivation of a luciferase reporter in response to T3, while SoThraa is constitutively active at a low level in the absence of ligand. To test whether interactions between the TH and CS systems occur during development, we initially quantified the in vivo receptor transcript expression levels, and then examined their response to treatment with triiodothyronine (T3) or cortisol. We find that sothraa and sothrb-L are autoregulated in response to exogenous T3 only during early larval development. T3 did not affect sogra-L expression levels, nor did cortisol alter levels of sothraa or sothrb-L at any stage. While differential expression of the receptors in response to non-canonical ligand hormone was not observed under the conditions in this study, the correlation between sothraa and sogra-L transcript abundance during development suggests a coordinated function of the TH and CS systems. By comparing the findings in the present study to earlier investigations, we suggest that the up-regulation of thraa may be a specific feature of metamorphosis in acanthomorph teleosts.

  19. Identification of a developmentally-regulated and psychostimulant-inducible novel rat gene mrt3 in the neocortex.

    PubMed

    Yamamoto, Naoki; Muraoka, Shin-ichiro; Kajii, Yasushi; Umino, Asami; Nishikawa, Toru

    2014-10-01

    The psychotomimetic effects of stimulant drugs including amphetamines and cocaine are known to change during the postnatal development in humans and experimental animals. To obtain an insight into the molecular basis of the onset of stimulant-induced psychosis, we have explored the gene transcripts that differentially respond to methamphetamine (MAP) in the developing rat brains using a differential cloning technique, the RNA arbitrarily-primed PCR. We identified from the rat neocortex a novel and developmentally regulated MAP-inducible gene mrt3 (MAP responsive transcript 3) that is transcribed to a presumable non-coding RNA of 3.8kb and is located on the reverse strand of the F-box/LRR-repeat protein 17-like gene mapped on the rat chromosome Xq12. The mrt3 mRNAs are predominantly expressed in the brain and lung. Acute MAP injection upregulated the mrt3 expression in the neocortex at postnatal day 50, but not days 8, 15 and 23, in a D1 receptor antagonist-sensitive manner. This upregulation was mimicked by another stimulant, cocaine, whereas pentobarbital and D1 antagonist failed to alter the mrt3 expression. Moreover, repeated treatment with MAP for 5 days inhibited the ability of the challenge dose of MAP or cocaine to increase the neocortical mrt3 expression without affecting the basal mrt3 mRNA levels on day 14 of withdrawal. These late-developing, cocaine-cross reactive, D1 antagonist-sensitive and long-term regulations of mrt3 by MAP are similar to those of stimulant-induced behavioral sensitization, a model of the onset and relapse of stimulant-induced psychosis and schizophrenia, and therefore may be associated with the pathophysiology of the model.

  20. The fragile X mental retardation protein developmentally regulates the strength and fidelity of calcium signaling in Drosophila mushroom body neurons.

    PubMed

    Tessier, Charles R; Broadie, Kendal

    2011-01-01

    Fragile X syndrome (FXS) is a broad-spectrum neurological disorder characterized by hypersensitivity to sensory stimuli, hyperactivity and severe cognitive impairment. FXS is caused by loss of the fragile X mental retardation 1 (FMR1) gene, whose FMRP product regulates mRNA translation downstream of synaptic activity to modulate changes in synaptic architecture, function and plasticity. Null Drosophila FMR1 (dfmr1) mutants exhibit reduced learning and loss of protein synthesis-dependent memory consolidation, which is dependent on the brain mushroom body (MB) learning and memory center. We targeted a transgenic GFP-based calcium reporter to the MB in order to analyze calcium dynamics downstream of neuronal activation. In the dfmr1 null MB, there was significant augmentation of the calcium transients induced by membrane depolarization, as well as elevated release of calcium from intracellular organelle stores. The severity of these calcium signaling defects increased with developmental age, although early stages were characterized by highly variable, low fidelity calcium regulation. At the single neuron level, both calcium transient and calcium store release defects were exhibited by dfmr1 null MB neurons in primary culture. Null dfmr1 mutants exhibit reduced brain mRNA expression of calcium-binding proteins, including calcium buffers calmodulin and calbindin, predicting that the inability to appropriately sequester cytosolic calcium may be the common mechanistic defect causing calcium accumulation following both influx and store release. Changes in the magnitude and fidelity of calcium signals in the absence of dFMRP likely contribute to defects in neuronal structure/function, leading to the hallmark learning and memory dysfunction of FXS.

  1. Developmental profile and hormonal regulation of the transcription factors broad and Krüppel homolog 1 in hemimetabolous thrips.

    PubMed

    Minakuchi, Chieka; Tanaka, Miho; Miura, Ken; Tanaka, Toshiharu

    2011-02-01

    In holometabolous insects, Krüppel homolog 1 (Kr-h1) and broad (br) are key players in the juvenile hormone (JH) regulation of metamorphosis: Kr-h1 is an early JH-response gene, while br is a transcription factor that directs pupal development. Thrips (Thysanoptera) are classified as hemimetabolous insects that develop directly from nymph to adult, but they have quiescent and non-feeding stages called propupa and pupa. We analyzed the developmental profiles of br and Kr-h1 in the western flower thrips Frankliniella occidentalis (Thripidae) that has one propupal instar and one pupal instar, and Haplothrips brevitubus (Phlaeothripidae) that has one propupal instar and two pupal instars, i.e. pupa I and pupa II. In F. occidentalis, the br mRNA levels were moderate in the embryonic stage, high at the larva-propupa transition, and low in the pre-final larval instar and the pupal stage, while Kr-h1 mRNA levels were high in the embryonic stage, remained at a moderate level in the larval and propupal stages, and low in the pupal stage. The expression profiles in H. brevitubus were very similar to those in F. occidentalis, except that the increase of br expression in the final larval stage occurs more slowly in H. brevitubus, and that the mRNA levels of br and Kr-h1 remained high in pupa I of H. brevitubus and then decreased. These profiles of br and Kr-h1 were comparable to those in holometabolous insects, although br expression found in thrips' embryogenesis is reminiscent of several hemimetabolous species. Treatment with an exogenous JH mimic (JHM) in distinct developmental stages consistently resulted in lethality as pupa of F. occidentalis or pupa II of H. brevitubus. Treatment with JHM to newly molted propupae caused prolonged expression of Kr-h1 and br in both species, suggesting that Kr-h1 and br could be involved in mediating anti-metamorphic signals of JHM.

  2. Developmental regulation of {beta}-hexosaminidase {alpha}- and {beta}-subunit gene expression in the rat reproductive system

    SciTech Connect

    Trasler, J.M.; Wakamatsu, N.; Gravel, R.A.; Benoit, G.

    1994-09-01

    {beta}-Hexosaminidase is an essential lysosomal enzyme whose absence in man results in a group of disorders, the G{sub M2} gangliosidoses. Enzyme activity for {beta}-hexosaminidase is many fold higher in the epididymis than in other tissues, is present in sperm and is postulated to be required for mammalian fertilization. To better understand how {beta}-hexosaminidase is regulated in the reproductive system, we quantitated the mRNA expression of the {alpha}- and {beta}-subunits (Hex {alpha} and Hex {beta}) of the enzyme in the developing rat testis and epididymis. Hex {alpha} mRNA was differentially expressed and abundant in adult rat testis and epididymis, 13- and 2-fold brain levels, respectively. In contrast, Hex {beta} mRNA levels in the testis and epididymis were .3- and 5-fold brain levels. Within the epididymis both Hex {alpha} and Hex {beta} mRNA concentrations were highest in the corpus, 1.5-fold and 9-fold initial segment values, respectively. During testis development from 7-91 days of age, testis levels of Hex {alpha} mRNA increased 10-fold and coincided with the appearance of spermatocytes and spermatids in the epithelium. In isolated male germ cells, Hex {alpha} expression was most abundant in haploid round spermatids. Hex {alpha} mRNA was undetectable after hypophysectomy and returned to normal after testosterone administration and the return of advanced germ cells to the testis. Hex {beta} mRNA was expressed at constant low levels throughout testis development. In the caput-corpus and cauda regions of the epididymis Hex {alpha} mRNA levels increased 2-fold between 14 and 91 days; during the same developmental period epididymal Hex {beta} mRNA levels increased dramatically, by 10-20 fold. In summary, Hex {alpha} and Hex {beta} mRNAs are differentially and developmentally expressed at high levels in the rat testis and epididymis and augur for an important role for {beta}-hexosaminidase in normal male reproductive function.

  3. Vagal Regulation of Heart Rate in the Prediction of Developmental Outcome for Very Low Birth Weight Preterm Infants.

    ERIC Educational Resources Information Center

    Doussard-Roosevelt, Jane A.; And Others

    1997-01-01

    Used heart rate and respiratory sinus arrhythmia (RSA) assessed at 33 to 35 weeks gestational age to predict developmental outcome at 3 years for very low birth weight infants. Found that RSA measures predicted developmental outcome beyond effects of birth weight, medical risk, and socioeconomic status. For infants < 1,000 grams, RSA maturation…

  4. c-Jun regulates cell cycle progression and apoptosis by distinct mechanisms.

    PubMed Central

    Wisdom, R; Johnson, R S; Moore, C

    1999-01-01

    c-Jun is a component of the transcription factor AP-1, which is activated by a wide variety of extracellular stimuli. The regulation of c-Jun is complex and involves both increases in the levels of c-Jun protein as well as phosphorylation of specific serines (63 and 73) by Jun N-terminal kinase (JNK). We have used fibroblasts derived from c-Jun null embryos to define the role of c-Jun in two separate processes: cell growth and apoptosis. We show that in fibroblasts, c-Jun is required for progression through the G1 phase of the cell cycle; c-Jun-mediated G1 progression occurs by a mechanism that involves direct transcriptional control of the cyclin D1 gene, establishing a molecular link between growth factor signaling and cell cycle regulators. In addition, c-Jun protects cells from UV-induced cell death and cooperates with NF-kappaB to prevent apoptosis induced by tumor necrosis factor alpha (TNFalpha). c-Jun mediated G1 progression is independent of phosphorylation of serines 63/73; however, protection from apoptosis in response to UV, a potent inducer of JNK/SAP kinase activity, requires serines 63/73. The results reveal critical roles for c-Jun in two different cellular processes and show that different extracellular stimuli can target c-Jun by distinct biochemical mechanisms. PMID:9878062

  5. The Use of Individual Growth and Developmental Indicators for Progress Monitoring and Intervention Decision Making in Early Education

    ERIC Educational Resources Information Center

    Walker, Dale; Carta, Judith J.; Greenwood, Charles R.; Buzhardt, Joseph F.

    2008-01-01

    Progress monitoring tools have been shown to be essential elements in current approaches to intervention problem-solving models. Such tools have been valuable not only in marking individual children's level of performance relative to peers but also in measuring change in skill level in a way that can be attributed to intervention and development.…

  6. Interleukin-6 promotes tumor progression in colitis-associated colorectal cancer through HIF-1α regulation

    PubMed Central

    Han, Jun; Xi, Qiulei; Meng, Qingyang; Liu, Jingzheng; Zhang, Yongxian; Han, Yusong; Zhuang, Qiulin; Jiang, Yi; Ding, Qiurong; Wu, Guohao

    2016-01-01

    Interleukin-6 (IL-6) is a well-known etiological factor of colitis-associated colorectal cancer (CAC) and has a significant role in CAC progression. In addition, hypoxia-inducible factor 1α (HIF-1α) serves a primary role in the progression of CAC. However, the association between IL-6 and HIF-1α during the progression of CAC remains unclear. To investigate this association, the present study induced CAC in a mouse model using azoxymethane and dextran sulfate sodium. In addition, an anti-IL-6 receptor antibody was used to inhibit IL-6. In this model, anti-IL-6 receptor antibody treatment significantly inhibited the development of CAC and the expression of HIF-1α, in colorectal adenomas and adenocarcinomas. In patients with CAC, the HIF-1α gene was demonstrated to be overexpressed in tumor tissue compared with adjacent non-malignant tissue. Furthermore, HIF-1α mRNA expression was positively correlated with serum IL-6 concentration. The results of the present study suggest that IL-6 promotes CAC progression, in the early stage of the disease, through HIF-1α regulation. PMID:28105173

  7. The Transcriptional Modulator Interferon-Related Developmental Regulator 1 in Osteoblasts Suppresses Bone Formation and Promotes Bone Resorption.

    PubMed

    Iezaki, Takashi; Onishi, Yuki; Ozaki, Kakeru; Fukasawa, Kazuya; Takahata, Yoshifumi; Nakamura, Yukari; Fujikawa, Koichi; Takarada, Takeshi; Yoneda, Yukio; Yamashita, Yui; Shioi, Go; Hinoi, Eiichi

    2016-03-01

    Bone homeostasis is maintained by the synergistic actions of bone-resorbing osteoclasts and bone-forming osteoblasts. Although interferon-related developmental regulator 1 (Ifrd1) has been identified as a transcriptional coactivator/repressor in various cells, little attention has been paid to its role in osteoblastogenesis and bone homeostasis thus far. Here, we show that Ifrd1 is a critical mediator of both the cell-autonomous regulation of osteoblastogenesis and osteoblast-dependent regulation of osteoclastogenesis. Osteoblast-specific deletion of murine Ifrd1 increased bone formation and decreased bone resorption, causing high bone mass. Ifrd1 deficiency enhanced osteoblast differentiation and maturation along with increased expression of Runx2 and osterix (Osx). Mechanistically, Ifrd1 deficiency increased the acetylation status of p65, a component of NF-κB, at residues K122 and K123 via the attenuation of the interaction between p65 and histone deacetylase (HDAC). This led to the nuclear export of p65 and a decrease in NF-κB-dependent Smad7 expression and the subsequent enhancement of Smad1/Smad5/Smad8-dependent transcription. Moreover, a high bone mass phenotype in the osteoblast-specific deletion of Ifrd1 was markedly rescued by the introduction of one Osx-floxed allele but not of Runx2-floxed allele. Coculture experiments revealed that Ifrd1-deficient osteoblasts have a higher osteoprotegerin (OPG) expression and a lower ability to support osteoclastogenesis. Ifrd1 deficiency attenuated the interaction between β-catenin and HDAC, subsequently increasing the acetylation of β-catenin at K49, leading to its nuclear accumulation and the activation of the β-catenin-dependent transcription of OPG. Collectively, the expression of Ifrd1 in osteoblasts repressed osteoblastogenesis and activated osteoclastogenesis through modulating the NF-κB/Smad/Osx and β-catenin/OPG pathways, respectively. These findings suggest that Ifrd1 has a pivotal role in bone

  8. A Retinoblastoma Orthologue Is a Major Regulator of S-Phase, Mitotic, and Developmental Gene Expression in Dictyostelium

    PubMed Central

    Strasser, Kimchi; Bloomfield, Gareth; MacWilliams, Asa; Ceccarelli, Adriano; Tsang, Adrian

    2012-01-01

    Background The retinoblastoma tumour suppressor, Rb, has two major functions. First, it represses genes whose products are required for S-phase entry and progression thus stabilizing cells in G1. Second, Rb interacts with factors that induce cell-cycle exit and terminal differentiation. Dictyostelium lacks a G1 phase in its cell cycle but it has a retinoblastoma orthologue, rblA. Methodology/Principal Findings Using microarray analysis and mRNA-Seq transcriptional profiling, we show that RblA strongly represses genes whose products are involved in S phase and mitosis. Both S-phase and mitotic genes are upregulated at a single point in late G2 and again in mid-development, near the time when cell cycling is reactivated. RblA also activates a set of genes unique to slime moulds that function in terminal differentiation. Conclusions Like its mammalian counterpart Dictyostelium, RblA plays a dual role, regulating cell-cycle progression and transcriptional events leading to terminal differentiation. In the absence of a G1 phase, however, RblA functions in late G2 controlling the expression of both S-phase and mitotic genes. PMID:22768168

  9. Follicular helper T cells progressively differentiate to regulate the germinal center response

    PubMed Central

    Licona-Limón, Paula; Esplugues, Enric; Flavell, Richard; Craft, Joe

    2016-01-01

    Germinal center (GC) B cells undergo affinity selection, dependent upon interactions with CD4+ follicular helper T (TFH) cells. We demonstrate that TFH cells progressed through transcriptionally and functionally distinct stages, providing differential signals for GC regulation. They initially localized proximally to mutating B cells, secreted IL-21, induced expression of the transcription factor Bcl-6 and selected high affinity B cell clones. As the GC response evolved, TFH cells extinguished IL-21 and switched to IL-4 production, showed robust CD40 ligand expression and promoted the development of antibody-secreting B cells via upregulation of the transcription factor Blimp-1. Thus, TFH cells in the B cell follicle progressively differentiated through stages of localization, cytokine production and surface ligand expression to fine-tune of the GC reaction. PMID:27573866

  10. [Regulation of terpene metabolism]. Annual progress report, March 15, 1990--March 14, 1991

    SciTech Connect

    Croteau, R.

    1991-12-31

    During the last grant period, we have completed studies on the key pathways of monoterpene biosynthesis and catabolism in sage and peppermint, and have, by several lines of evidence, deciphered the rate-limiting step of each pathway. We have at least partially purified and characterized the relevant enzymes of each pathway. We have made a strong case, based on analytical, in vivo, and in vitro studies, that terpene accumulation depends upon the balance between biosynthesis and catabolism, and provided supporting evidence that these processes are developmentally-regulated and very closely associated with senescence of the oil glands. Oil gland ontogeny has been characterized at the ultrastructural level. We have exploited foliar-applied bioregulators to delay gland senescence, and have developed tissue explant and cell culture systems to study several elusive aspects of catabolism. We have isolated pure gland cell clusters and localized monoterpene biosynthesis and catabolism within these structures, and have used these preparations as starting materials for the purification to homogeneity of target ``regulatory`` enzymes. We have thus developed the necessary background knowledge, based on a firm understanding of enzymology, as well as the necessary experimental tools for studying the regulation of monoterpene metabolism at the molecular level. Furthermore, we are now in a position to extend our systematic approach to other terpenoid classes (C{sub 15}-C{sub 30}) produced by oil glands.

  11. Androgen Regulated SPARCL1 in the Tumor Microenvironment Inhibits Metastatic Progression

    PubMed Central

    Hurley, Paula J.; Hughes, Robert M.; Simons, Brian W.; Huang, Jessie; Miller, Rebecca M.; Shinder, Brian; Haffner, Michael C.; Esopi, David; Kimura, Yasunori; Jabbari, Javaneh; Ross, Ashley E.; Erho, Nicholas; Vergara, Ismael A.; Faraj, Sheila F.; Davicioni, Elai; Netto, George J.; Yegnasubramanian, Srinivasan; An, Steven S.; Schaeffer, Edward M.

    2015-01-01

    Prostate cancer is a leading cause of cancer death in men due to the subset of cancers that progress to metastasis. Prostate cancers are thought to be hardwired to androgen receptor (AR) signaling, but AR-regulated changes in the prostate that facilitate metastasis remain poorly understood. We previously noted a marked reduction in Secreted protein, acidic and rich in cysteine-like 1 (SPARCL1) expression during invasive phases of androgen-induced prostate growth, suggesting that this may be a novel invasive program governed by AR. Herein, we show that SPARCL1 loss occurs concurrently with AR amplification or overexpression in patient based data. Mechanistically, we demonstrate that SPARCL1 expression is directly suppressed by androgen-induced AR activation and binding at the SPARCL1 locus via an epigenetic mechanism, and these events can be pharmacologically attenuated with either AR antagonists or HDAC inhibitors. We establish using the Hi-Myc model of prostate cancer that in Hi-Myc/Sparcl1−/− mice, SPARCL1 functions to suppress cancer formation. Moreover, metastatic progression of Myc-CaP orthotopic allografts is restricted by SPARCL1 in the tumor microenvironment. Specifically, we show that SPARCL1 both tethers to collagen in the extracellular matrix (ECM) and binds to the cell's cytoskeleton. SPARCL1 directly inhibits the assembly of focal adhesions thereby constraining the transmission of cell traction forces. Our findings establish a new insight into AR-regulated prostate epithelial movement and provide a novel framework whereby, SPARCL1 in the ECM microenvironment restricts tumor progression by regulating the initiation of the network of physical forces that may be required for metastatic-invasion of prostate cancer. PMID:26294211

  12. Arabidopsis CYP98A3 Mediating Aromatic 3-Hydroxylation. Developmental Regulation of the Gene, and Expression in Yeast1

    PubMed Central

    Nair, Ramesh B.; Xia, Qun; Kartha, Cyril J.; Kurylo, Eugen; Hirji, Rozina N.; Datla, Raju; Selvaraj, Gopalan

    2002-01-01

    The general phenylpropanoid pathways generate a wide array of aromatic secondary metabolites that range from monolignols, which are ubiquitous in all plants, to sinapine, which is confined to crucifer seeds. The biosynthesis of these compounds involves hydroxylated and methoxylated cinnamyl acid, aldehyde, or alcohol intermediates. Of the three enzymes originally proposed to hydroxylate the 4-, 3-, and 5-positions of the aromatic ring, cinnamate 4-hydroxylase (C4H), which converts trans-cinnamic acid to p-coumaric acid, is the best characterized and is also the archetypal plant P450 monooxygenase. Ferulic acid 5-hydroxylase (F5H), a P450 that catalyzes 5-hydroxylation, has also been studied, but the presumptive 3-hydroxylase converting p-coumarate to caffeate has been elusive. We have found that Arabidopsis CYP98A3, also a P450, could hydroxylate p-coumaric acid to caffeic acid in vivo when expressed in yeast (Saccharomyces cerevisiae) cells, albeit very slowly. CYP98A3 transcript was found in Arabidopsis stem and silique, resembling both C4H and F5H in this respect. CYP98A3 showed further resemblance to C4H in being highly active in root, but differed from F5H in this regard. In transgenic Arabidopsis, the promoters of CYP98A3 and C4H showed wound inducibility and a comparable developmental regulation throughout the life cycle, except in seeds, where the CYP98A3 promoter construct was inactive while remaining active in silique walls. Within stem and root tissue, the gene product and the promoter activity of CYP98A3 were most abundant in lignifying cells. Collectively, these studies show involvement of CYP98A3 in the general phenylpropanoid metabolism, and suggest a downstream function for CYP98A3 relative to the broader and upstream role of C4H. PMID:12226501

  13. Expression and developmental regulation of oxytocin (OT) and oxytocin receptors (OTR) in the enteric nervous system (ENS) and intestinal epithelium.

    PubMed

    Welch, Martha G; Tamir, Hadassah; Gross, Kara J; Chen, Jason; Anwar, Muhammad; Gershon, Michael D

    2009-01-10

    Although oxytocin (OT) and oxytocin receptor (OTR) are known for roles in parturition and milk let-down, they are not hypothalamus-restricted. OT is important in nurturing and opposition to stress. Transcripts encoding OT and OTR have been reported in adult human gut, and OT affects intestinal motility. We tested the hypotheses that OT is endogenous to the enteric nervous system (ENS) and that OTR signaling may participate in enteric neurophysiology. Reverse transcriptase polymerase chain reaction confirmed OT and OTR transcripts in adult mouse and rat gut and in precursors of enteric neurons immunoselected from fetal rats. Enteric OT and OTR expression continued through adulthood but was developmentally regulated, peaking at postnatal day 7. Coincidence of the immunoreactivities of OTR and the neural marker Hu was 100% in the P3 and 71% in the adult myenteric plexus, when submucosal neurons were also OTR-immunoreactive. Co-localization with NeuN established that intrinsic primary afferent neurons are OTR-expressing. Because OTR transcripts and protein were detected in the nodose ganglia, OT signaling might also affect extrinsic primary afferent neurons. Although OT immunoreactivity was found only in approximately 1% of myenteric neurons, extensive OT-immunoreactive varicosities surrounded many others. Villus enterocytes were OTR-immunoreactive through postnatal day 17; however, by postnatal day 19, immunoreactivity waned to become restricted to crypts and concentrated at crypt-villus junctions. Immunoelectron microscopy revealed plasmalemmal OTR at enterocyte adherens junctions. We suggest that OT and OTR signaling might be important in ENS development and function and might play roles in visceral sensory perception and neural modulation of epithelial biology.

  14. Activity-dependent repression of Cbln1 expression: mechanism for developmental and homeostatic regulation of synapses in the cerebellum.

    PubMed

    Iijima, Takatoshi; Emi, Kyoichi; Yuzaki, Michisuke

    2009-04-29

    Cbln1, which belongs to the C1q/tumor necrosis factor superfamily, is released from cerebellar granule cells and plays a crucial role in forming and maintaining excitatory synapses between parallel fibers (PFs; axons of granule cells) and Purkinje cells not only during development but also in the adult cerebellum. Although neuronal activity is known to cause morphological changes at synapses, how Cbln1 signaling is affected by neuronal activity remains unclear. Here, we show that chronic stimulation of neuronal activity by elevating extracellular K(+) levels or by adding kainate decreased the expression of cbln1 mRNA within several hours in mature granule cells in a manner dependent on L-type voltage-dependent Ca(2+) channels and calcineurin. Chronic activity also reduced Cbln1 protein levels within a few days, during which time the number of excitatory synapses on Purkinje cell dendrites was reduced; this activity-induced reduction of synapses was prevented by the addition of exogenous Cbln1 to the culture medium. Therefore, the activity-dependent downregulation of cbln1 may serve as a new presynaptic mechanism by which PF-Purkinje cell synapses adapt to chronically elevated activity, thereby maintaining homeostasis. In addition, the expression of cbln1 mRNA was prevented when immature granule cells were maintained in high-K(+) medium. Since immature granule cells are chronically depolarized before migrating to the internal granule layer, this depolarization-dependent regulation of cbln1 mRNA expression may also serve as a developmental switch to facilitate PF synapse formation in mature granule cells in the internal granule layer.

  15. DNA methyltransferase expressions in Japanese rice fish (Oryzias latipes) embryogenesis is developmentally regulated and modulated by ethanol and 5-azacytidine.

    PubMed

    Dasmahapatra, Asok K; Khan, Ikhlas A

    2015-01-01

    We aimed to investigate the impact of the epigenome in inducting fetal alcohol spectrum disorder (FASD) phenotypes in Japanese rice fish embryogenesis. One of the significant events in epigenome is DNA methylation which is catalyzed by DNA methyltransferase (DNMT) enzymes. We analyzed DNMT enzyme mRNA expressions in Japanese rice fish development starting from fertilized eggs to hatching and also in embryos exposed for first 48h of development either to ethanol (300mM) or to 5-azacytidine (5-azaC; 2mM), an inhibitor of DNMT enzyme activity. As observed in FASD phenotypes, 5-azaC exposure was able to induce microcephaly and craniofacial cartilage deformities in Japanese rice fish. Moreover, we have observed that expression of DNMTs (dnmt1, dnmt3aa, and dnmt3bb.1) are developmentally regulated; high mRNA copies were found in early stages (1-2day-post-fertilization, dpf), followed by gradual reduction until hatched. In ethanol-treated embryos, compared to controls, dnmt1 mRNA is in reduced level in 2dpf and in enhanced level in 6dpf embryos. While dnmt3aa and 3bb.1 remained unaltered. In contrast, embryos exposed to 5-azaC have an enhanced level of dnmt1 and dnmt3bb.1 mRNAs both in 2 and 6dpf embryos while dnmt3aa is enhanced only in 6dpf embryos. Moreover, endocannabinoid receptor 1a (cnr1a) mRNA which was found to be reduced by ethanol remained unaltered and cnr1b and cnr2 mRNAs, which were remained unaltered by ethanol, were increased significantly by 5-azaC in 6dpf embryos. This study indicates that the craniofacial defects observed in FASD phenotypes are the results of dysregulations in DNMT expressions.

  16. Astrocytes regulate developmental changes in the chloride ion gradient of embryonic rat ventral spinal cord neurons in culture

    PubMed Central

    Li, Yong-Xin; Schaffner, Anne E; Walton, Marc K; Barker, Jeffery L

    1998-01-01

    Embryonic rat ventral spinal cord neurons were dissociated at day 15 and grown on: (i) poly-D-lysine (PDL); (ii) a confluent monolayer of type I astrocytes; or (iii) PDL in astrocyte-conditioned medium (ACM) to examine the influence of astroglia on the regulation of GABAA receptor/Cl− channel properties. Potentiometric oxonol dye recordings of intact cells indicated that embryonic neurons were uniformly depolarized by muscimol. The depolarizing effects disappeared in cells dissociated during the early postnatal period and recovered in culture for 24 h. Similar recordings using the calcium-imaging dye fura-2 AM revealed that GABA or muscimol triggered a sustained rise in cytosolic Ca2+ (Cac2+) in embryonic neurons that was dependent on extracellular Ca2+, blocked by bicuculline and nifedipine and sensitive to changes in extracellular chloride. The incidence and amplitude of the Ca2+ response decreased with time in vitro and was accelerated in neurons cultured on astrocytes compared with those on PDL. Perforated patch-clamp recordings revealed that GABA depolarized neurons in a Cl−-dependent and bicuculline-sensitive manner. Both the resting membrane potential and the GABA equilibrium potential became more hyperpolarized with time in vitro. Astrocytes and ACM accelerated the transformation of GABAergic potential responses from depolarizing to hyperpolarizing. The change occurred over the first 4 days in co-culture or in ACM but took more than 2 weeks in neurons cultured on PDL alone. The intrinsic, elementary properties of GABAA receptor/Cl− channels including open time and unitary conductance changed independently of the presence of astrocytes or ACM. Mean open time of the dominant kinetic component decreased and conductance increased with time in vitro. In sum, astrocytes accelerate the developmental change in the Cl− ion gradient extrinsic to GABAA receptor/Cl− channels, which is critical for triggering Ca2+ entry, without influencing parallel changes in

  17. Expression and Developmental Regulation of Oxytocin (OT) and Oxytocin Receptors (OTR) in the Enteric Nervous System (ENS) and Intestinal Epithelium

    PubMed Central

    Welch, Martha G.; Tamir, Hadassah; Gross, Kara J.; Chen, Jason; Anwar, Muhammad; Gershon, Michael D.

    2011-01-01

    Although oxytocin (OT) and oxytocin receptor (OTR) are known for roles in parturition and milk let-down, they are not hypothalamus-restricted. OT is important in nurturing and opposition to stress. Transcripts encoding OT and OTR have been reported in adult human gut, and OT affects intestinal motility. We tested the hypotheses that OT is endogenous to the enteric nervous system (ENS) and that OTR signaling may participate in enteric neurophysiology. Reverse transcriptase polymerase chain reaction confirmed OT and OTR transcripts in adult mouse and rat gut and in precursors of enteric neurons immunoselected from fetal rats. Enteric OT and OTR expression continued through adulthood but was developmentally regulated, peaking at postnatal day 7. Coincidence of the immunoreactivities of OTR and the neural marker Hu was 100% in the P3 and 71% in the adult myenteric plexus, when submucosal neurons were also OTR-immunoreactive. Co-localization with NeuN established that intrinsic primary afferent neurons are OTR-expressing. Because OTR transcripts and protein were detected in the nodose ganglia, OT signaling might also affect extrinsic primary afferent neurons. Although OT immunoreactivity was found only in ~1% of myenteric neurons, extensive OT-immunoreactive varicosities surrounded many others. Villus enterocytes were OTR-immunoreactive through postnatal day 17; however, by postnatal day 19, immunoreactivity waned to become restricted to crypts and concentrated at crypt-villus junctions. Immunoelectron microscopy revealed plasmalemmal OTR at enterocyte adherens junctions. We suggest that OT and OTR signaling might be important in ENS development and function and might play roles in visceral sensory perception and neural modulation of epithelial biology. PMID:19003903

  18. The ciliary GTPase Arl13b regulates cell migration and cell cycle progression

    PubMed Central

    Pruski, Michal; Rajnicek, Ann; Yang, Zhifu; Clancy, Hannah; Ding, Yu-Qiang; McCaig, Colin D.; Lang, Bing

    2016-01-01

    ABSTRACT The GTPase ARL13B is localized to primary cilia; small cellular protrusions that act as antennae. Its defective ARL13B hennin (HNN) variant is linked causally with Joubert Syndrome, a developmental ciliopathy attributed to poor sensing of extracellular chemical gradients. We tested the hypothesis that impaired detection of extracellular voltage gradients also contributes to the HNN phenotype. In vitro, extracellular electric fields stimulated migration of wild type (WT) and HNN fibroblasts toward the cathode but the field only increased the migration speed of WT cells. Cilia on WT cells did not align to the field vector. HNN cells divided more slowly than WT cells, arresting at the G2/M phase. Mechanistically, HNN cells had reduced phospho-ERK1/2 signaling and elevated levels of Suppressor of Fused protein. These suggest that cells may not be able to read extracellular chemical cues appropriately, resulting in deficits in cell migration and proliferation. Finally, an increase in tubulin stabilization (more detyrosinated tubulin) confirmed the general stagnation of HNN cells, which may further contribute to slower migration and cell cycle progression. We conclude that Arl13b dysfunction resulted in HNN cell stagnation due to poor growth factor signaling and impaired detection of extracellular electrical gradients, and that the role of Arl13b in cell proliferation may be understated. PMID:26963749

  19. Feedback regulation of NEUROG2 activity by MTGR1 is required for progression of neurogenesis.

    PubMed

    Aaker, Joshua D; Patineau, Andrea L; Yang, Hyun-Jin; Ewart, David T; Gong, Wuming; Li, Tongbin; Nakagawa, Yasushi; McLoon, Steven C; Koyano-Nakagawa, Naoko

    2009-12-01

    The sequential steps of neurogenesis are characterized by highly choreographed changes in transcription factor activity. In contrast to the well-studied mechanisms of transcription factor activation during neurogenesis, much less is understood regarding how such activity is terminated. We previously showed that MTGR1, a member of the MTG family of transcriptional repressors, is strongly induced by a proneural basic helix-loop-helix transcription factor, NEUROG2 in developing nervous system. In this study, we describe a novel feedback regulation of NEUROG2 activity by MTGR1. We show that MTGR1 physically interacts with NEUROG2 and represses transcriptional activity of NEUROG2. MTGR1 also prevents DNA binding of the NEUROG2/E47 complex. In addition, we provide evidence that proper termination of NEUROG2 activity by MTGR1 is necessary for normal progression of neurogenesis in the developing spinal cord. These results highlight the importance of feedback regulation of proneural gene activity in neurodevelopment.

  20. Feedback regulation of NEUROG2 activity by MTGR1 is required for progression of neurogenesis

    PubMed Central

    Aaker, Joshua D.; Patineau, Andrea L.; Yang, Hyun-jin; Ewart, David T.; Gong, Wuming; Li, Tongbin; Nakagawa, Yasushi; McLoon, Steven C.; Koyano-Nakagawa, Naoko

    2009-01-01

    The sequential steps of neurogenesis are characterized by highly choreographed changes in transcription factor activity. In contrast to the well-studied mechanisms of transcription factor activation during neurogenesis, much less is understood regarding how such activity is terminated. We previously showed that MTGR1, a member of the MTG family of transcriptional repressors, is strongly induced by a proneural basic helix-loop-helix transcription factor, NEUROG2 in developing nervous system. In this study, we describe a novel feedback regulation of NEUROG2 activity by MTGR1. We show that MTGR1 physically interacts with NEUROG2 and represses transcriptional activity of NEUROG2. MTGR1 also prevents DNA binding of the NEUROG2/E47 complex. In addition, we provide evidence that proper termination of NEUROG2 activity by MTGR1 is necessary for normal progression of neurogenesis in the developing spinal cord. These results highlight the importance of feedback regulation of proneural gene activity in neurodevelopment. PMID:19646530

  1. Regulated protein expression for in vivo gene therapy for neurological disorders: progress, strategies, and issues.

    PubMed

    Manfredsson, Fredric P; Bloom, David C; Mandel, Ronald J

    2012-11-01

    The field of in vivo gene therapy has matured to the point where there are numerous clinical trials underway including late-stage clinical trials. Several viral vectors are especially efficient and support lifetime protein expression in the brain and a number of clinical trials are underway for various progressive or chronic neurological disorders including Parkinson's disease, Alzheimer's disease, and Batten's disease. To date, however, none of the vectors in clinical use have any direct way to reverse or control their transgene product in the event continued protein expression should become problematic. Several schemes that use elements within the vector design have been developed that allow an external drug or pro-drug to alter ongoing protein expression after in vivo gene transfer. The most promising and most studied regulated protein expression methods for in vivo gene transfer are reviewed. In addition, potential scientific and clinical advantages of transgene regulation for gene therapy are discussed.

  2. Functional relevance of "seed" and "non-seed" sequences in microRNA-mediated promotion of C. elegans developmental progression.

    PubMed

    Zhang, Huibin; Artiles, Karen L; Fire, Andrew Z

    2015-11-01

    The founding heterochronic microRNAs, lin-4 and let-7, together with their validated targets and well-characterized phenotypes in C. elegans, offer an opportunity to test functionality of microRNAs in a developmental context. In this study, we defined sequence requirements at the microRNA level for these two microRNAs, evaluating lin-4 and let-7 mutant microRNAs for their ability to support temporal development under conditions where the wild-type lin-4 and let-7 gene products are absent. For lin-4, we found a strong requirement for seed sequences, with function drastically affected by several central mutations in the seed sequence, while rescue was retained by a set of mutations peripheral to the seed. let-7 rescuing activity was retained to a surprising degree by a variety of central seed mutations, while several non-seed mutant effects support potential noncanonical contributions to let-7 function. Taken together, this work illustrates both the functional partnership between seed and non-seed sequences in mediating C. elegans temporal development and a diversity among microRNA effectors in the contributions of seed and non-seed regions to activity.

  3. Developmental Readiness of Normal Full Term Infants To Progress from Exclusive Breastfeeding to the Introduction of Complementary Foods: Reviews of the Relevant Literature Concerning Infant Immunologic, Gastrointestinal, Oral Motor and Maternal Reproductive and Lactational Development.

    ERIC Educational Resources Information Center

    Naylor, Audrey J., Ed.; Morrow, Ardythe L., Ed.

    This review of the developmental readiness of normal, full-term infants to progress from exclusive breastfeeding to the introduction of complementary foods is the result of the international debate regarding the best age to introduce complementary foods into the diet of the breastfed human infant. After a list of definitions, four papers focus on:…

  4. In-silico analysis and expression profiling implicate diverse role of EPSPS family genes in regulating developmental and metabolic processes

    PubMed Central

    2014-01-01

    Background The EPSPS, EC 2.5.1.19 (5-enolpyruvylshikimate −3-phosphate synthase) is considered as one of the crucial enzyme in the shikimate pathway for the biosynthesis of essential aromatic amino acids and secondary metabolites in plants, fungi along with microorganisms. It is also proved as a specific target of broad spectrum herbicide glyphosate. Results On the basis of structure analysis, this EPSPS gene family comprises the presence of EPSPS I domain, which is highly conserved among different plant species. Here, we followed an in-silico approach to identify and characterize the EPSPS genes from different plant species. On the basis of their phylogeny and sequence conservation, we divided them in to two groups. Moreover, the interacting partners and co-expression data of the gene revealed the importance of this gene family in maintaining cellular and metabolic functions in the cell. The present study also highlighted the highest accumulation of EPSPS transcript in mature leaves followed by young leaves, shoot and roots of tobacco. In order to gain the more knowledge about gene family, we searched for the previously reported motifs and studied its structural importance on the basis of homology modelling. Conclusions The results presented here is a first detailed in-silico study to explore the role of EPSPS gene in forefront of different plant species. The results revealed a great deal for the diversification and conservation of EPSPS gene family across different plant species. Moreover, some of the EPSPS from different plant species may have a common evolutionary origin and may contain same conserved motifs with related and important molecular function. Most importantly, overall analysis of EPSPS gene elucidated its pivotal role in immense function within the plant, both in regulating plant growth as well its development throughout the life cycle of plant. Since EPSPS is a direct target of herbicide glyphosate, understanding its mechanism for regulating

  5. Alternative splicing and developmental and hormonal regulation of porcine comparative gene identification-58 (CGI-58) mRNA.

    PubMed

    Li, X; Suh, Y; Kim, E; Moeller, S J; Lee, K

    2012-12-01

    The process of lipolysis is essential for regulating the catabolism of cellular fat stores. Therefore, knowledge of lipolysis contributes to improving porcine production, such as reducing back fat, enhancing lean meat, and controlling marbling. Comparative gene identification-58 (CGI-58) plays an important role in the multi-enzyme-mediated process of lipolysis. It was identified as the co-activator of adipose triglyceride lipase (ATGL), which performs the first step in breaking down triacylglycerol and generating diacylglycerol and NEFA. We cloned and sequenced the CGI-58 cDNA and deduced the AA sequences in 3 breeds of swine (Duroc, Berkshire, and Landrace). Homologies were found with the human, mouse, and chicken for the lipid droplet binding domain, the α/β hydrolase domain, and the lysophosphatidic acid acyltransferase (LPAAT) domain, which demonstrates conservation of CGI-58 across species. An alternatively spliced isoform with an exon 3 deletion was identified. Interestingly, this unique isoform contains the lipid droplet-binding domain but lacks the LPAAT domain due to an open reading frame (ORF) shift that creates a premature stop codon. Furthermore, porcine CGI-58 is expressed in multiple organs and tissues but is most predominant in adipose tissue. Porcine adipose and stromal-vascular (SV) cell fractionation reveals that CGI-58 and ATGL are highly expressed (P < 0.01) in mature adipocytes. The expressions of both CGI-58 and ATGL mRNA were found to increase (P < 0.05) at d 6 of SV cell culture, confirming their upregulation during adipogenesis and differentiation. Also, the results from in vitro cell culture showed that insulin decreased (P < 0.05) the expressions of both CGI-58 and ATGL in a dose-dependent manner. Overall, these results report the cDNA and AA sequences of porcine CGI-58 with identification of its unique alternatively spliced variant. The results of the study also reveal the developmental and hormonal regulation of porcine CGI-58 gene

  6. Developmental regulation of neuroligin genes in Japanese ricefish (Oryzias latipes) embryogenesis maintains the rhythm during ethanol-induced fetal alcohol spectrum disorder.

    PubMed

    Haron, Mona H; Khan, Ikhlas A; Dasmahapatra, Asok K

    2014-01-01

    Although prenatal alcohol exposure is the potential cause of fetal alcohol spectrum disorder (FASD) in humans, the molecular mechanism(s) of FASD is yet unknown. We have used Japanese ricefish (Oryzias latipes) embryogenesis as an animal model of FASD and reported that this model has effectively generated several phenotypic features in the cardiovasculature and neurocranial cartilages by developmental ethanol exposure which is analogous to human FASD phenotypes. As FASD is a neurobehavioral disorder, we are searching for a molecular target of ethanol that alters neurological functions. In this communication, we have focused on neuroligin genes (nlgn) which are known to be active at the postsynaptic side of both excitatory and inhibitory synapses of the central nervous system. There are six human NLGN homologs of Japanese ricefish reported in public data bases. We have partially cloned these genes and analyzed their expression pattern during normal development and also after exposing the embryos to ethanol. Our data indicate that the expression of all six nlgn genes in Japanese ricefish embryos is developmentally regulated. Although ethanol is able to induce developmental abnormalities in Japanese ricefish embryogenesis comparable to the FASD phenotypes, quantitative real-time PCR (qPCR) analysis of nlgn mRNAs indicate unresponsiveness of these genes to ethanol. We conclude that the disruption of the developmental rhythm of Japanese ricefish embryogenesis by ethanol that leads to FASD may not affect the nlgn gene expression at the message level.

  7. Differences in kinase-mediated regulation of cell cycle progression in normal and transformed cells

    SciTech Connect

    Crissman, H.A.; Gadbois, D.M.; Tobey, R.A.; Stevenson, A.P.; Kraemer, P.M.; Bustos, L.D.; Dickson, J.A.; Bradbury, E.M. )

    1993-01-01

    Staurosporine (Stsp), a general protein kinase inhibitor, was used to investigate the role of kinase-mediated mechanisms in regulating mammalian cell proliferation. Low levels of Stsp (1-2nM) prevented nontransformed cells from entering S phase, indicating that protein phosphorylation processes are essential for commitment of DNA replication in normal cells. Cells resumed cycling when Stsp was removed. The period of sensitivity of nontransformed human diploid fibroblasts to low levels of the drug commenced 3 h later than the G0/G1 boundary and extended through the G1/S boundary. The initial block point at 3 h corresponds neither to the serum nor the amino acid restriction point. In contrast, neither low nor high concentrations (100nm) of Stsp affected G1 progression of transformed cells. High drug concentrations blocked normal cells in G1 and G2 but affected only G2-progression in transformed cells. These results indicate that kinase-mediated regulation of DNA replication is lost as a result of neoplastic transformation, but the G2-arrest mechanism remains intact.

  8. Growth Attenuation with Developmental Schedule Progression in Embryos and Early Larvae of Sterechinus neumayeri Raised under Elevated CO2

    PubMed Central

    Yu, Pauline C.; Sewell, Mary A.; Matson, Paul G.; Rivest, Emily B.; Kapsenberg, Lydia; Hofmann, Gretchen E.

    2013-01-01

    The Southern Ocean, a region that will be an ocean acidification hotspot in the near future, is home to a uniquely adapted fauna that includes a diversity of lightly-calcified invertebrates. We exposed the larvae of the echinoid Sterechinus neumayeri to environmental levels of CO2 in McMurdo Sound (control: 410 µatm, Ω = 1.35) and mildly elevated pCO2 levels, both near the level of the aragonite saturation horizon (510 µatm pCO2, Ω = 1.12), and to under-saturating conditions (730 µatm, Ω = 0.82). Early embryological development was normal under these conditions with the exception of the hatching process, which was slightly delayed. Appearance of the initial calcium carbonate (CaCO3) spicule nuclei among the primary mesenchyme cells of the gastrulae was synchronous between control and elevated pCO2 treatments. However, by prism (7 days after the initial appearance of the spicule nucleus), elongating arm rod spicules were already significantly shorter in the highest CO2 treatment. Unfed larvae in the 730 µatm pCO2 treatment remained significantly smaller than unfed control larvae at days 15–30, and larvae in the 510 µatm treatment were significantly smaller at day 20. At day 30, the arm lengths were more differentiated between 730 µatm and control CO2 treatments than were body lengths as components of total length. Arm length is the most plastic morphological aspect of the echinopluteus, and appears to exhibit the greatest response to high pCO2/low pH/low carbonate, even in the absence of food. Thus, while the effects of elevated pCO2 representative of near future climate scenarios are proportionally minor on these early developmental stages, the longer term effects on these long-lived invertebrates is still unknown. PMID:23300974

  9. A mutation in cnot8, component of the Ccr4-not complex regulating transcript stability, affects expression levels of developmental regulators and reveals a role of Fgf3 in development of caudal hypothalamic dopaminergic neurons.

    PubMed

    Koch, Peter; Löhr, Heiko B; Driever, Wolfgang

    2014-01-01

    While regulation of the activity of developmental control genes at the transcriptional level as well as by specific miRNA-based degradation are intensively studied, little is known whether general cellular mechanisms controlling mRNA decay may contribute to differential stability of mRNAs of developmental control genes. Here, we investigate whether a mutation in the deadenylation dependent mRNA decay pathway may reveal differential effects on developmental mechanisms, using dopaminergic differentiation in the zebrafish brain as model system. In a zebrafish genetic screen aimed at identifying genes controlling dopaminergic neuron development we isolated the m1061 mutation that selectively caused increased dopaminergic differentiation in the caudal hypothalamus, while other dopaminergic groups were not affected. Positional cloning revealed that m1061 causes a premature stop codon in the cnot8 open reading frame. Cnot8 is a component of the Ccr4-Not complex and displays deadenylase activity, which is required for removal of the poly (A) tail in bulk mRNA turnover. Analyses of expression of developmental regulators indicate that loss of Cnot8 activity results in increased mRNA in situ hybridization signal levels for a subset of developmental control genes. We show that in the area of caudal hypothalamic dopaminergic differentiation, mRNA levels for several components of the FGF signaling pathway, including Fgf3, FGF receptors, and FGF target genes, are increased. Pharmacological inhibition of FGF signaling or a mutation in the fgf3 gene can compensate the gain of caudal hypothalamic dopaminergic neurons in cnot8m1061 mutants, indicating a role for Fgf3 in control of development of this dopaminergic population. The cnot8m1061 mutant phenotype provides an in vivo system to study roles of the Cnot8 deadenylase component of the mRNA decay pathway in vertebrate development. Our data indicate that attenuation of Cnot8 activity differentially affects mRNA levels of

  10. A Mutation in cnot8, Component of the Ccr4-Not Complex Regulating Transcript Stability, Affects Expression Levels of Developmental Regulators and Reveals a Role of Fgf3 in Development of Caudal Hypothalamic Dopaminergic Neurons

    PubMed Central

    Koch, Peter; Löhr, Heiko B.; Driever, Wolfgang

    2014-01-01

    While regulation of the activity of developmental control genes at the transcriptional level as well as by specific miRNA-based degradation are intensively studied, little is known whether general cellular mechanisms controlling mRNA decay may contribute to differential stability of mRNAs of developmental control genes. Here, we investigate whether a mutation in the deadenylation dependent mRNA decay pathway may reveal differential effects on developmental mechanisms, using dopaminergic differentiation in the zebrafish brain as model system. In a zebrafish genetic screen aimed at identifying genes controlling dopaminergic neuron development we isolated the m1061 mutation that selectively caused increased dopaminergic differentiation in the caudal hypothalamus, while other dopaminergic groups were not affected. Positional cloning revealed that m1061 causes a premature stop codon in the cnot8 open reading frame. Cnot8 is a component of the Ccr4-Not complex and displays deadenylase activity, which is required for removal of the poly (A) tail in bulk mRNA turnover. Analyses of expression of developmental regulators indicate that loss of Cnot8 activity results in increased mRNA in situ hybridization signal levels for a subset of developmental control genes. We show that in the area of caudal hypothalamic dopaminergic differentiation, mRNA levels for several components of the FGF signaling pathway, including Fgf3, FGF receptors, and FGF target genes, are increased. Pharmacological inhibition of FGF signaling or a mutation in the fgf3 gene can compensate the gain of caudal hypothalamic dopaminergic neurons in cnot8m1061 mutants, indicating a role for Fgf3 in control of development of this dopaminergic population. The cnot8m1061 mutant phenotype provides an in vivo system to study roles of the Cnot8 deadenylase component of the mRNA decay pathway in vertebrate development. Our data indicate that attenuation of Cnot8 activity differentially affects mRNA levels of

  11. Developmental Toxicology##

    EPA Science Inventory

    Developmental toxicology encompasses the study of developmental exposures, pharmacokinetics, mechanisms, pathogenesis, and outcomes potentially leading to adverse health effects. Manifestations of developmental toxicity include structural malformations, growth retardation, functi...

  12. Effects of FGF10 on bovine oocyte meiosis progression, apoptosis, embryo development and relative abundance of developmentally important genes in vitro.

    PubMed

    Pomini Pinto, R F; Fontes, P K; Loureiro, B; Sousa Castilho, A C; Sousa Ticianelli, J; Montanari Razza, E; Satrapa, R A; Buratini, J; Moraes Barros, C

    2015-02-01

    Fibroblast growth factor (FGF10) acts at the cumulus oocyte complex, increasing the expression of cumulus cell expansion-related genes and oocyte competency genes. We tested the hypothesis that addition of FGF10 to the maturation medium improves oocyte maturation, decreases the percentage of apoptotic oocytes and increases development to the blastocyst stage while increasing the relative abundance of developmentally important genes (COX2, CDX2 and PLAC8). In all experiments, oocytes were matured for 22 h in TCM-199 supplemented with 0, 2.5, 10 or 50 ng/ml FGF10. In Experiment 1, after maturation, oocytes were stained with Hoechst to evaluate meiosis progression (metaphase I, intermediary phases and extrusion of the first polar body) and submitted to the TUNEL assay to evaluate apoptosis. In Experiment 2, oocytes were fertilized and cultured to the blastocyst stage. Blastocysts were frozen for analysis of COX2, CDX2 and PLAC8 relative abundance. In Experiment 1, 2.5 ng/ml FGF10 increased (p < 0.05) the percentage of oocytes with extrusion of the first polar body (35%) compared to 0, 10 and 50 ng/ml FGF10 (21, 14 and 12%, respectively) and FGF10 decreased the percentage of oocytes that were TUNEL positive in all doses studied. In Experiment 2, there was no difference in the percentage of oocytes becoming blastocysts between treatments and control. Real-time RT-PCR showed a tendency of 50 ng/ml FGF10 to increase the relative abundance of COX2 and PLAC8 and of 10 ng/ml FGF10 to increase CDX2. In conclusion, the addition of FGF10 to the oocyte maturation medium improves oocyte maturation in vitro, decreases the percentage of apoptotic oocytes and tends to increase the relative abundance of developmentally important genes.

  13. [Regulation of terpene metabolism]. Annual progress report, March 15, 1989--March 14, 1990

    SciTech Connect

    Croteau, R.

    1989-11-09

    Terpenoid oils, resins, and waxes from plants are important renewable resources. The objective of this project is to understand the regulation of terpenoid metabolism using the monoterpenes (C{sub 10}) as a model. The pathways of monoterpene biosynthesis and catabolism have been established, and the relevant enzymes characterized. Developmental studies relating enzyme levels to terpene accumulation within the oil gland sites of synthesis, and work with bioregulators, indicate that monoterpene production is controlled by terpene cyclases, the enzymes catalyzing the first step of the monoterpene pathway. As the leaf oil glands mature, cyclase levels decline and monoterpene biosynthesis ceases. Yield then decreases as the monoterpenes undergo catabolism by a process involving conversion to a glycoside and transport from the leaf glands to the root. At this site, the terpenoid is oxidatively degraded to acetate that is recycled into other lipid metabolites. During the transition from terpene biosynthesis to catabolism, the oil glands undergo dramatic ultrastructural modification. Degradation of the producing cells results in mixing of previously compartmentized monoterpenes with the catabolic enzymes, ultimately leading to yield decline. This regulatory model is being applied to the formation of other terpenoid classes (C{sub 15} C{sub 20}, C{sub 30}, C{sub 40}) within the oil glands. Preliminary investigations on the formation of sesquiterpenes (C{sub 15}) suggest that the corresponding cyclases may play a lesser role in determining yield of these products, but that compartmentation effects are important. From these studies, a comprehensive scheme for the regulation of terpene metabolism is being constructed. Results from this project wail have important consequences for the yield and composition of terpenoid natural products that can be made available for industrial exploitation.

  14. Isolation of two novel ras genes in Dictyostelium discoideum; evidence for a complex, developmentally regulated ras gene subfamily.

    PubMed

    Daniel, J; Bush, J; Cardelli, J; Spiegelman, G B; Weeks, G

    1994-02-01

    In Dictyostelium discoideum, three ras genes (rasD, rasG and rasB) and one ras-related gene (rap1) have been previously isolated and characterized, and the deduced amino acid sequence of their predicted protein products share at least 50% sequence identity with the human H-Ras protein. We have now cloned and characterized two additional members of the ras gene subfamily in Dictyostelium, rasC and rasS. These genes are developmentally regulated and unlike the previously isolated Dictyostelium ras genes, maximum levels of their transcripts were detected during aggregation, suggesting that the encoded proteins have distinct functions during aggregation. The rasC cDNA encodes a 189 amino acid protein that is 65% identical to the Dictyostelium RasD and RasG proteins and 56% identical to the human H-Ras protein. The predicted 194 amino acid gene product encoded by rasS is 60% identical to the Dictyostelium RasD and RasG proteins and 54% identical to the human H-Ras protein. Whereas RasD, RasG, RasB and Rap1 are totally conserved in their putative effector domains relative to H-Ras, RasC and RasS have single amino acid substitutions in their effector domains, consistent with the idea that they have unique functions. In RasC, aspartic acid-38 has been replaced by asparagine (D38N), and in RasS, isoleucine-36 has been replaced by leucine (I36L). In addition, both proteins have several differences in the effector-proximal domain, a domain which is believed to play a role in Ras target activation. In RasC, there is a single conservative amino acid change in the canonical sequence of the binding site for the Ras-specific monoclonal antibody Y13-259, and consequently, RasC is less immunoreactive with the antibody than either of the Dictyostelium RasD or RasG proteins. In contrast, RasS, which has three substitutions in the Y13-259 binding site, does not react with the Y13-259 antibody.

  15. Female-specific gene expression in dioecious liverwort Pellia endiviifolia is developmentally regulated and connected to archegonia production

    PubMed Central

    2014-01-01

    developmentally regulated. The contribution of the identified genes may be crucial for successful liverwort sexual reproduction. PMID:24939387

  16. DHN melanin biosynthesis in the plant pathogenic fungus Botrytis cinerea is based on two developmentally regulated key enzyme (PKS)-encoding genes.

    PubMed

    Schumacher, Julia

    2016-02-01

    Botrytis cinerea is the causal agent of gray mold disease in various plant species and produces grayish macroconidia and/or black sclerotia at the end of the infection cycle. It has been suggested that the pigmentation is due to the accumulation of 1,8-dihydroxynaphthalene (DHN) melanin. To unravel its basis and regulation, the putative melanogenic and regulatory genes were identified and functionally characterized. Unlike other DHN melanin-producing fungi, B. cinerea and other Leotiomycetes contain two key enzyme (PKS)-encoding enzymes. Bcpks12 and bcpks13 are developmentally regulated and are required for melanogenesis in sclerotia and conidia respectively. BcYGH1 converts the BcPKS13 product and contributes thereby to conidial melanogenesis. In contrast, enzymes acting downstream in conversion of the PKS products (BcBRN2, BcSCD1 and BcBRN1) are required for both, sclerotial and conidial melanogenesis, suggesting that DHN melanogenesis in B. cinerea follows a non-linear pathway that is rather unusual for secondary metabolic pathways. Regulation of the melanogenic genes involves three pathway-specific transcription factors (TFs) that are clustered with bcpks12 or bcpks13 and other developmental regulators such as light-responsive TFs. Melanogenic genes are dispensable in vegetative mycelia for proper growth and virulence. However, DHN melanin is considered to contribute to the longevity of the reproduction structures.

  17. KIF14 negatively regulates Rap1a–Radil signaling during breast cancer progression

    PubMed Central

    Ahmed, Syed M.; Thériault, Brigitte L.; Uppalapati, Maruti; Chiu, Catherine W.N.; Gallie, Brenda L.; Sidhu, Sachdev S.

    2012-01-01

    The small GTPase Rap1 regulates inside-out integrin activation and thereby influences cell adhesion, migration, and polarity. Several Rap1 effectors have been described to mediate the cellular effects of Rap1 in a context-dependent manner. Radil is emerging as an important Rap effector implicated in cell spreading and migration, but the molecular mechanisms underlying its functions are unclear. We report here that the kinesin KIF14 associates with the PDZ domain of Radil and negatively regulates Rap1-mediated inside-out integrin activation by tethering Radil on microtubules. The depletion of KIF14 led to increased cell spreading, altered focal adhesion dynamics, and inhibition of cell migration and invasion. We also show that Radil is important for breast cancer cell proliferation and for metastasis in mice. Our findings provide evidence that the concurrent up-regulation of Rap1 activity and increased KIF14 levels in several cancers is needed to reach optimal levels of Rap1–Radil signaling, integrin activation, and cell–matrix adhesiveness required for tumor progression. PMID:23209302

  18. Netrin-1 up-regulation in inflammatory bowel diseases is required for colorectal cancer progression

    PubMed Central

    Paradisi, Andrea; Maisse, Carine; Coissieux, Marie-May; Gadot, Nicolas; Lépinasse, Florian; Delloye-Bourgeois, Céline; Delcros, Jean-Guy; Svrcek, Magali; Neufert, Clemens; Fléjou, Jean-François; Scoazec, Jean-Yves; Mehlen, Patrick

    2009-01-01

    Chronic inflammation and cancer are intimately associated. This is particularly true for inflammatory bowel diseases (IBD), such as ulcerative colitis and Crohn's disease, which show a major increased risk for colorectal cancer. While the understanding of the molecular pathogenesis of IBD has recently improved, the mechanisms that link these chronic inflammatory states to colorectal cancer development are in large part unknown. One of these mechanisms is NF-κB pathway activation which in turn may contribute to tumor formation by providing anti-apoptotic survival signals to the epithelial cells. Based on the observation that netrin-1, the anti-apoptotic ligand for the dependence receptors DCC and UNC5H is up-regulated in colonic crypts in response to NF-κB, we show here that colorectal cancers from inflammatory bowel diseases patients have selected up-regulation of netrin-1. Moreover, we demonstrate that this inflammation-driven netrin-1 up-regulation is causal for colorectal cancer development as interference with netrin-1 autocrine loop in a mouse model for ulcerative colitis-associated colorectal cancer, while showing no effect on inflammation, inhibits colorectal cancer progression. PMID:19721007

  19. Netrin-1 up-regulation in inflammatory bowel diseases is required for colorectal cancer progression.

    PubMed

    Paradisi, Andrea; Maisse, Carine; Coissieux, Marie-May; Gadot, Nicolas; Lépinasse, Florian; Delloye-Bourgeois, Céline; Delcros, Jean-Guy; Svrcek, Magali; Neufert, Clemens; Fléjou, Jean-François; Scoazec, Jean-Yves; Mehlen, Patrick

    2009-10-06

    Chronic inflammation and cancer are intimately associated. This is particularly true for inflammatory bowel diseases (IBD), such as ulcerative colitis and Crohn's disease, which show a major increased risk for colorectal cancer. While the understanding of the molecular pathogenesis of IBD has recently improved, the mechanisms that link these chronic inflammatory states to colorectal cancer development are in large part unknown. One of these mechanisms is NF-kappaB pathway activation which in turn may contribute to tumor formation by providing anti-apoptotic survival signals to the epithelial cells. Based on the observation that netrin-1, the anti-apoptotic ligand for the dependence receptors DCC and UNC5H is up-regulated in colonic crypts in response to NF-kappaB, we show here that colorectal cancers from inflammatory bowel diseases patients have selected up-regulation of netrin-1. Moreover, we demonstrate that this inflammation-driven netrin-1 up-regulation is causal for colorectal cancer development as interference with netrin-1 autocrine loop in a mouse model for ulcerative colitis-associated colorectal cancer, while showing no effect on inflammation, inhibits colorectal cancer progression.

  20. Fibromodulin: a master regulator of myostatin controlling progression of satellite cells through a myogenic program.

    PubMed

    Lee, Eun Ju; Jan, Arif Tasleem; Baig, Mohammad Hassan; Ashraf, Jalaluddin Mohammad; Nahm, Sang-Soep; Kim, Yong-Woon; Park, So-Young; Choi, Inho

    2016-08-01

    Differentiation of muscle satellite cells (MSCs) involves interaction of the proteins present in the extracellular matrix (ECM) with MSCs to regulate their activity, and therefore phenotype. Herein, we report fibromodulin (FMOD), a member of the proteoglycan family participating in the assembly of ECM, as a novel regulator of myostatin (MSTN) during myoblast differentiation. In addition to having a pronounced effect on the expression of myogenic marker genes [myogenin (MYOG) and myosin light chain 2 (MYL2)], FMOD was found to maintain the transcriptional activity of MSTN Moreover, coimmunoprecipitation and in silico studies performed to investigate the interaction of FMOD helped confirm that it antagonizes MSTN function by distorting its folding and preventing its binding to activin receptor type IIB. Furthermore, in vivo studies revealed that FMOD plays an active role in healing by increasing satellite cell recruitment to sites of injury. Together, these findings disclose a hitherto unrecognized regulatory role for FMOD in MSCs and highlight new mechanisms whereby FMOD circumvents the inhibitory effects of MSTN and triggers myoblast differentiation. These findings offer a basis for the design of novel MSTN inhibitors that promote muscle regeneration after injury or for the development of pharmaceutical agents for the treatment of different muscle atrophies.-Lee, E. J., Jan, A. T., Baig, M. H., Ashraf, J. M., Nahm, S.-S., Kim, Y.-W., Park, S.-Y., Choi, I. Fibromodulin: a master regulator of myostatin controlling progression of satellite cells through a myogenic program.

  1. The nuclear hormone receptor BgE75 links molting and developmental progression in the direct-developing insect Blattella germanica.

    PubMed

    Mané-Padrós, Daniel; Cruz, Josefa; Vilaplana, Lluïsa; Pascual, Nuria; Bellés, Xavier; Martín, David

    2008-03-01

    Ecdysteroid hormones regulate key developmental processes throughout the life cycle of insects. 20-Hydroxyecdysone (20E) acts upon binding to a heterodimeric receptor formed by the nuclear receptors EcR and USP. The receptor, once 20E bounds to it, elicits cascades of gene expression that mediate and amplify the hormonal signal. The molecular characterization of the 20E-mediated hierarchy of transcription factors has been analyzed in detail in holometabolous insects, especially in Drosophila melanogaster, but rarely in more basal hemimetabolous species. Using the hemimetabolous species Blattella germanica (German cockroach) as model, we have cloned and characterized five isoforms of B. germanica E75, a member of the nuclear receptor family participating in the 20E-triggered genetic hierarchy. The five isoforms present characteristic expression patterns during embryo and nymphal development, and experiments in vitro with fat body tissue have shown that the five isoforms display specific 20E responsiveness. RNAi experiments in vivo during the penultimate and last nymphal instars of B. germanica revealed that BgE75 is required for successfully complete nymphal-nymphal and nymphal-adult transitions. Detailed analysis of knockdown specimens during the last nymphal instar showed that BgE75 is required for the rise of circulating ecdysteroids that occurs towards the end of the instar. The main cause of ecdysteroid deficiency in BgE75 knockdowns is the premature stage-specific degeneration of the prothoracic gland. As a consequence, BgE75 knockdown nymphs do not molt, live for up to 90 days and start the adult developmental program properly, in spite of remaining as nymphs from a morphological point of view. Finally, RNAi of specific isoforms during the last nymphal instar of B. germanica has showed that they are functionally redundant. Furthermore, it also revealed the occurrence of a complex regulatory relationship among BgE75 isoforms, which is responsible of their

  2. Skp2 Regulates G2/M Progression in a p53-dependent Manner

    PubMed Central

    Hu, Rong

    2008-01-01

    Targeted proteasomal degradation mediated by E3 ubiquitin ligases controls cell cycle progression, and alterations in their activities likely contribute to malignant cell proliferation. S phase kinase-associated protein 2 (Skp2) is the F-box component of an E3 ubiquitin ligase complex that targets p27Kip1 and cyclin E1 to the proteasome. In human melanoma, Skp2 is highly expressed, regulated by mutant B-RAF, and required for cell growth. We show that Skp2 depletion in melanoma cells resulted in a tetraploid cell cycle arrest. Surprisingly, co-knockdown of p27Kip1 or cyclin E1 failed to prevent the tetraploid arrest induced by Skp2 knockdown. Enhanced Aurora A phosphorylation and repression of G2/M regulators cyclin B1, cyclin-dependent kinase 1, and cyclin A indicated a G2/early M phase arrest in Skp2-depleted cells. Furthermore, expression of nuclear localized cyclin B1 prevented tetraploid accumulation after Skp2 knockdown. The p53 status is most frequently wild type in melanoma, and the tetraploid arrest and down-regulation of G2/M regulatory genes were strongly dependent on wild-type p53 expression. In mutant p53 melanoma lines, Skp2 depletion did not induce cell cycle arrest despite up-regulation of p27Kip1. These data indicate that elevated Skp2 expression may overcome p53-dependent cell cycle checkpoints in melanoma cells and highlight Skp2 actions that are independent of p27Kip1 degradation. PMID:18716061

  3. RhoE is required for contact inhibition and negatively regulates tumor initiation and progression

    PubMed Central

    Hernández-Sánchez, Marta; Poch, Enric; Guasch, Rosa M.; Ortega, Joaquín; López-Almela, Inmaculada; Palmero, Ignacio; Pérez-Roger, Ignacio

    2015-01-01

    RhoE is a small GTPase involved in the regulation of actin cytoskeleton dynamics, cell cycle and apoptosis. The role of RhoE in cancer is currently controversial, with reports of both oncogenic and tumor-suppressive functions for RhoE. Using RhoE-deficient mice, we show here that the absence of RhoE blunts contact-inhibition of growth by inhibiting p27Kip1 nuclear translocation and cooperates in oncogenic transformation of mouse primary fibroblasts. Heterozygous RhoE+/gt mice are more susceptible to chemically induced skin tumors and RhoE knock-down results in increased metastatic potential of cancer cells. These results indicate that RhoE plays a role in suppressing tumor initiation and progression. PMID:26036260

  4. Overexpression of NOTCH-regulated Ankyrin Repeat Protein is associated with papillary thyroid carcinoma progression

    PubMed Central

    Zhang, Mingdi; Qin, Yiyu; Zuo, Bin; Gong, Wei; Zhang, Shenglai; Gong, Yurong; Quan, Zhiwei; Chu, Bingfeng

    2017-01-01

    Papillary thyroid cancer (PTC) is one of the endocrine cancers with high clinical and genetic heterogeneity. NOTCH signaling and its downstream NOTCH-Regulated Ankyrin Repeat Protein (NRARP) have been implicated in oncogenesis of many cancers, but the roles in PTCs are less studied. In this study, we show that NRARP is frequently over-expressed in thyroid carcinoma. The over-activation of NRARP is highly and positively correlated with NOTCH genes. Moreover, we find that the expression of NRARP is highly associated with several epithelial mesenchymal transition (EMT) markers and contributes to poor survival outcomes. Therefore, these results indicate that NRARP is an important clinical biomarker in thyroid carcinoma and it promotes EMT induction as well as the progression of PTCs via NOTCH signaling activation. PMID:28207739

  5. DNA-PKcs mediated transcriptional regulation drives prostate cancer progression and metastasis

    PubMed Central

    Goodwin, Jonathan F.; Kothari, Vishal; Drake, Justin M.; Zhao, Shuang; Dylgjeri, Emanuela; Dean, Jeffry L.; Schiewer, Matthew J.; McNair, Christopher; Jones, Jennifer K.; Aytes, Alvaro; Magee, Michael S.; Snook, Adam E.; Zhu, Ziqi; Den, Robert B.; Birbe, Ruth C.; Gomella, Leonard G.; Graham, Nicholas A.; Vashisht, Ajay A.; Wohlschlegel, James A.; Graeber, Thomas G.; Karnes, R. Jeffrey; Takhar, Mandeep; Davicioni, Elai; Tomlins, Scott A.; Abate-Shen, Cory; Sharifi, Nima; Witte, Owen N.; Feng, Felix Y.; Knudsen, Karen E.

    2015-01-01

    SUMMARY Emerging evidence demonstrates that the DNA repair kinase DNA-PKcs exerts divergent roles in transcriptional regulation of unsolved consequence. Here, in vitro and in vivo interrogation demonstrate that DNA-PKcs functions as a selective modulator of transcriptional networks that induce cell migration, invasion, and metastasis. Accordingly, suppression of DNA-PKcs inhibits tumor metastases. Clinical assessment revealed that DNA-PKcs is significantly elevated in advanced disease, and independently predicts for metastases, recurrence, and reduced overall survival. Further investigation demonstrated that DNA-PKcs in advanced tumors is highly activated, independent of DNA damage indicators. Combined, these findings reveal unexpected DNA-PKcs functions, identify DNA-PKcs as a potent driver of tumor progression and metastases, and nominate DNA-PKcs as a therapeutic target for advanced malignancies. PMID:26175416

  6. RhoE is required for contact inhibition and negatively regulates tumor initiation and progression.

    PubMed

    Hernández-Sánchez, Marta; Poch, Enric; Guasch, Rosa M; Ortega, Joaquín; López-Almela, Inmaculada; Palmero, Ignacio; Pérez-Roger, Ignacio

    2015-07-10

    RhoE is a small GTPase involved in the regulation of actin cytoskeleton dynamics, cell cycle and apoptosis. The role of RhoE in cancer is currently controversial, with reports of both oncogenic and tumor-suppressive functions for RhoE. Using RhoE-deficient mice, we show here that the absence of RhoE blunts contact-inhibition of growth by inhibiting p27Kip1 nuclear translocation and cooperates in oncogenic transformation of mouse primary fibroblasts. Heterozygous RhoE+/gt mice are more susceptible to chemically induced skin tumors and RhoE knock-down results in increased metastatic potential of cancer cells. These results indicate that RhoE plays a role in suppressing tumor initiation and progression.

  7. Muscarinic acetylcholine receptors regulating cell cycle progression are expressed in human gingival keratinocytes.

    PubMed

    Arredondo, J; Hall, L L; Ndoye, A; Chernyavsky, A I; Jolkovsky, D L; Grando, S A

    2003-02-01

    We have previously reported the presence in human gingival keratinocytes (GKC) of choline acetyltransferase, the acetylcholine (ACh) synthesizing enzyme, acetylcholinesterase, the ACh degrading enzyme, and alpha 3, alpha 5, alpha 7, beta 2 as well as alpha 9 nicotinic ACh receptor subunits. To expand the knowledge about the role of ACh in oral biology, we investigated the presence of the muscarinic ACh receptor (mAChR) subtypes in GKC. RT-PCR demonstrated the presence of m2, m3, m4, and m5 mRNA transcripts. Synthesis of the respective proteins was verified by immunoblotting with the subtype-specific antibodies that revealed receptor bands at the expected molecular weights. The antibodies mapped mAChR subtypes in the epithelium of human attached gingiva and also visualized them on the cell membrane of cultured GKC. The whole cell radioligand binding assay revealed that GKC have specific binding sites for the muscarinic ligand [3H]quinuclidinyl benzilate, Bmax = 222.9 fmol/106 cells with a Kd of 62.95 pM. The downstream coupling of the mAChRs to regulation of cell cycle progression in GKC was studied using quantitative RT-PCR and immunoblotting assays. Incubation of GKC for 24 h with 10 micro m muscarine increased relative amounts of Ki-67, PCNA and p53 mRNAs and PCNA, cyclin D1, p21 and p53 proteins. These effects were abolished in the presence of 50 micro m atropine. The finding in GKC of mAChRs coupled to regulation of the cell cycle progression demonstrate further the structure/function of the non-neuronal cholinergic system operating in human oral epithelium. The results obtained in this study help clarify the role for keratinocyte ACh axis in the physiologic control of oral gingival homeostasis.

  8. miR-107 regulates tumor progression by targeting NF1 in gastric cancer.

    PubMed

    Wang, Shizhi; Ma, Gaoxiang; Zhu, Haixia; Lv, Chunye; Chu, Haiyan; Tong, Na; Wu, Dongmei; Qiang, Fulin; Gong, Weida; Zhao, Qinghong; Tao, Guoquan; Zhou, Jianwei; Zhang, Zhengdong; Wang, Meilin

    2016-11-09

    Our previous genome-wide miRNA microarray study revealed that miR-107 was upregulated in gastric cancer (GC). In this study we aimed to explore its biological role in the pathogenesis of GC. Integrating in silico prediction algorithms with western blotting assays revealed that miR-107 inhibition enhanced NF1 (neurofibromin 1) mRNA and protein levels, suggesting that NF1 is one of miR-107 targets in GC. Luciferase reporter assay revealed that miR-107 suppressed NF1 expression by binding to the first potential binding site within the 3'-UTR of NF1 mRNA. mRNA stable assay indicated this binding could result in NF1 mRNA instability, which might contribute to its abnormal protein expression. Functional analyses such as cell growth, transwell migration and invasion assays were used to investigate the role of interaction between miR-107 and its target on GC development and progression. Moreover, We investigated the association between the clinical phenotype and the status of miR-107 expression in 55 GC tissues, and found the high expression contributed to the tumor size and depth of invasion. The results exhibited that down regulation of miR-107 opposed cell growth, migration, and invasion, whereas NF1 repression promoted these phenotypes. Our findings provide a mechanism by which miR-107 regulates NF1 in GC, as well as highlight the importance of interaction between miR-107 and NF1 in GC development and progression.

  9. TRPC6 regulates cell cycle progression by modulating membrane potential in bone marrow stromal cells

    PubMed Central

    Ichikawa, Jun; Inoue, Ryuji

    2014-01-01

    Background and Purpose Ca2+ influx is important for cell cycle progression, but the mechanisms involved seem to vary. We investigated the potential roles of transient receptor potential (TRP) channels and store-operated Ca2+ entry (SOCE)-related molecules STIM (stromal interaction molecule)/Orai in the cell cycle progression of rat bone marrow stromal cells (BMSCs), a reliable therapeutic resource for regenerative medicine. Experimental Approach PCR and immunoblot analyses were used to examine mRNA and protein levels, fluorescence imaging and patch clamping for Ca2+ influx and membrane potential measurements, and flow cytometry for cell cycle analysis. Key Results Cell cycle synchronization of BMSCs revealed S phase-specific enhancement of TRPC1, STIM and Orai mRNA and protein expression. In contrast, TRPC6 expression decreased in the S phase and increased in the G1 phase. Resting membrane potential (RMP) of BMSCs was most negative and positive in the S and G1 phases, respectively, and was accompanied by an enhancement and attenuation of SOCE respectively. Chemically depolarizing/hyperpolarizing the membrane erased these differences in SOCE magnitude during the cell cycle. siRNA knockdown of TRPC6 produced a negative shift in RMP, increased SOCE and caused redistribution of BMSCs with increased populations in the S and G2/M phases and accumulation of cyclins A2 and B1. A low concentration of Gd3+ (1 μM) suppressed BMSC proliferation at its concentration to inhibit SOC channels relatively specifically. Conclusions and Implications TRPC6, by changing the membrane potential, plays a pivotal role in controlling the SOCE magnitude, which is critical for cell cycle progression of BMSCs. This finding provides a new therapeutic strategy for regulating BMSC proliferation. PMID:25041367

  10. OTX1 Contributes to Hepatocellular Carcinoma Progression by Regulation of ERK/MAPK Pathway

    PubMed Central

    2016-01-01

    Orthodenticlehomeobox 1 (OTX1) overexpression had previously been associated with the progression of several tumors. The present study aimed to determine the expression and role of OTX1 in human hepatocellular carcinoma (HCC). The expression level of OTX1 was examined by quantitative real-time PCR (qRT-PCR) in 10 samples of HCC and paired adjacent non-cancerous tissues, and by immunohistochemistry (IHC) analysis in 128 HCC samples and matched controls. The relationship between OTX1 expression and the clinicopathological features werealso analyzed. Furthermore, the effects of OTX1 knockdown on cell proliferation and migration were determined in HCC cell lines. Axenograft mouse model was also established to investigate the role of OTX1 in HCC tumor growth. TheqRT-PCR and IHC analyses revealed that OTX1 was significantly elevated in HCC tissues compared with the paired non-cancerous controls. Expression of OTX1 was positively correlated with nodal metastasis status (P = 0.009) and TNM staging (P = 0.001) in HCC tissues. In addition, knockdown of OTX1 by shRNA significantly inhibited the proliferation and migration, and induced cell cycle arrest in S phase in vitro. Tumor growth was markedly inhibited by OTX1 silencing in the xenograft. Moreover, OTX1 silencing was causable for the decreased phosphorylation level of ERK/MAPK signaling. In conclusion, OTX1 contributes to HCC progression possibly by regulation of ERK/MAPK pathway. OTX1 may be a novel target for molecular therapy towards HCC. PMID:27478331

  11. Celecoxib suppresses hepatoma stemness and progression by up-regulating PTEN

    PubMed Central

    Kuo, Hsiao-Mei; Liu, Li-Fen; Hu, Tsung-Hui; Sun, Cheuk-Kwan; Kung, Mei-Lang; Lin, Shih-Wei; Wang, E-Ming; Ma, Yi-Ling; Cheng, Kwan-Hung; Lai, Kwok Hung; Wen, Zhi-Hong; Hsu, Ping-I; Tai, Ming-Hong

    2014-01-01

    Celecoxib, a COX-2 inhibitor and non-steroidal anti-inflammatory drug, can prevent several types of cancer, including hepatocellular carcinoma (HCC). Here we show that celecoxib suppressed the self-renewal and drug-pumping functions in HCC cells. Besides, celecoxib depleted CD44 + /CD133 + hepatic cancer stem cells (hCSC). Prostaglandin E2 (PGE2) and CD133 overexpression did not reverse the celecoxib-induced depletion of hCSC. Also, celecoxib inhibited progression of rat Novikoff hepatoma. Moreover, a 60-day celecoxib program increased the survival rate of rats with hepatoma. Histological analysis revealed that celecoxib therapy reduced the abundance of CD44 + /CD133 + hCSCs in hepatoma tissues. Besides, the hCSCs depletion was associated with elevated apoptosis and blunted proliferation and angiogenesis in hepatoma. Celecoxib therapy activated peroxisome proliferator-activated receptor γ (PPARγ) and up-regulated PTEN, thereby inhibiting Akt and disrupting hCSC expansion. PTEN gene delivery by adenovirus reduced CD44/CD133 expression in vitro and hepatoma formation in vivo. This study suggests that celecoxib suppresses cancer stemness and progression of HCC via activation of PPARγ/PTEN signaling. PMID:24721996

  12. Prolyl-isomerase Pin1 controls Notch3 protein expression and regulates T-ALL progression

    PubMed Central

    Franciosa, G; Diluvio, G; Gaudio, F Del; Giuli, M V; Palermo, R; Grazioli, P; Campese, A F; Talora, C; Bellavia, D; D'Amati, G; Besharat, Z M; Nicoletti, C; Siebel, C W; Choy, L; Rustighi, A; Sal, G Del; Screpanti, I; Checquolo, S

    2016-01-01

    Deregulated Notch signaling is associated with T-cell Acute Lymphoblastic Leukemia (T-ALL) development and progression. Increasing evidence reveals that Notch pathway has an important role in the invasion ability of tumor cells, including leukemia, although the underlying molecular mechanisms remain mostly unclear. Here, we show that Notch3 is a novel target protein of the prolyl-isomerase Pin1, which is able to regulate Notch3 protein processing and to stabilize the cleaved product, leading to the increased expression of the intracellular domain (N3IC), finally enhancing Notch3-dependent invasiveness properties. We demonstrate that the combined inhibition of Notch3 and Pin1 in the Notch3-overexpressing human leukemic TALL-1 cells reduces their high invasive potential, by decreasing the expression of the matrix metalloprotease MMP9. Consistently, Pin1 depletion in a mouse model of Notch3-induced T-ALL, by reducing N3IC expression and signaling, impairs the expansion/invasiveness of CD4+CD8+ DP cells in peripheral lymphoid and non-lymphoid organs. Notably, in in silico gene expression analysis of human T-ALL samples we observed a significant correlation between Pin1 and Notch3 expression levels, which may further suggest a key role of the newly identified Notch3-Pin1 axis in T-ALL aggressiveness and progression. Thus, combined suppression of Pin1 and Notch3 proteins may be exploited as an additional target therapy for T-ALL. PMID:26876201

  13. NFAT1 transcription factor regulates cell cycle progression and cyclin E expression in B lymphocytes.

    PubMed

    Teixeira, Leonardo K; Carrossini, Nina; Sécca, Cristiane; Kroll, José E; DaCunha, Déborah C; Faget, Douglas V; Carvalho, Lilian D S; de Souza, Sandro J; Viola, João P B

    2016-09-01

    The NFAT family of transcription factors has been primarily related to T cell development, activation, and differentiation. Further studies have shown that these ubiquitous proteins are observed in many cell types inside and outside the immune system, and are involved in several biological processes, including tumor growth, angiogenesis, and invasiveness. However, the specific role of the NFAT1 family member in naive B cell proliferation remains elusive. Here, we demonstrate that NFAT1 transcription factor controls Cyclin E expression, cell proliferation, and tumor growth in vivo. Specifically, we show that inducible expression of NFAT1 inhibits cell cycle progression, reduces colony formation, and controls tumor growth in nude mice. We also demonstrate that NFAT1-deficient naive B lymphocytes show a hyperproliferative phenotype and high levels of Cyclin E1 and E2 upon BCR stimulation when compared to wild-type B lymphocytes. NFAT1 transcription factor directly regulates Cyclin E expression in B cells, inhibiting the G1/S cell cycle phase transition. Bioinformatics analysis indicates that low levels of NFAT1 correlate with high expression of Cyclin E1 in different human cancers, including Diffuse Large B-cell Lymphomas (DLBCL). Together, our results demonstrate a repressor role for NFAT1 in cell cycle progression and Cyclin E expression in B lymphocytes, and suggest a potential function for NFAT1 protein in B cell malignancies.

  14. Dynamic SUMO modification regulates mitotic chromosome assembly and cell cycle progression in Caenorhabditis elegans

    PubMed Central

    Pelisch, Federico; Sonneville, Remi; Pourkarimi, Ehsan; Agostinho, Ana; Blow, J. Julian; Gartner, Anton; Hay, Ronald T.

    2014-01-01

    The small ubiquitin-like modifier (SUMO), initially characterized as a suppressor of a mutation in the gene encoding the centromeric protein MIF2, is involved in many aspects of cell cycle regulation. The dynamics of conjugation and deconjugation and the role of SUMO during the cell cycle remain unexplored. Here we used Caenorhabditis elegans to establish the contribution of SUMO to a timely and accurate cell division. Chromatin-associated SUMO conjugates increase during metaphase but decrease rapidly during anaphase. Accumulation of SUMO conjugates on the metaphase plate and proper chromosome alignment depend on the SUMO E2 conjugating enzyme UBC-9 and SUMO E3 ligase PIASGEI-17. Deconjugation is achieved by the SUMO protease ULP-4 and is crucial for correct progression through the cell cycle. Moreover, ULP-4 is necessary for Aurora BAIR-2 extraction from chromatin and relocation to the spindle mid-zone. Our results show that dynamic SUMO conjugation plays a role in cell cycle progression. PMID:25475837

  15. Promoter methylation of PCDH10 by HOTAIR regulates the progression of gastrointestinal stromal tumors

    PubMed Central

    Lee, Na Keum; Lee, Jung Hwa; Kim, Won Kyu; Yun, Seongju; Youn, Young Hoon; Park, Chan Hyuk; Choi, Yun Young; Kim, Hogeun; Lee, Sang Kil

    2016-01-01

    HOTAIR, a long non-coding RNA (lncRNA), plays a crucial role in tumor initiation and metastasis by interacting with the PRC2 complex and the modulation of its target genes. The role of HOTAIR in gastrointestinal stromal tumors (GISTs) is remains unclear. Herein we investigate the mechanism of HOTAIR in the genesis and promotion of GISTs. The expression of HOTAIR was found to be higher in surgically resected high-risk GISTs than that in low- and intermediate-risk GISTs. Using GIST-T1 and GIST882 cells, we demonstrated that HOTAIR repressed apoptosis, was associated with cell cycle progression, and controlled the invasion and migration of GIST cells. Using a gene expression microarray and lists of HOTAIR-associated candidate genes, we suggested that protocadherin 10 (PCDH10) is a key molecule. PCDH10 expression was significantly decreased in GIST-T1 and GIST882 cells, possibly as a consequence of hypermethylation. We observed that HOTAIR induced PCDH10 methylation in a SUZ12-dependent manner. In this study, we found that the malignant character of GISTs was initiated and amplified by PCDH10 in a process regulated by HOTAIR. In summary, our findings imply that PCDH10 and HOTAIR may be useful markers of disease progression and therapeutic targets. PMID:27659532

  16. dKDM5/LID regulates H3K4me3 dynamics at the transcription-start site (TSS) of actively transcribed developmental genes.

    PubMed

    Lloret-Llinares, Marta; Pérez-Lluch, Sílvia; Rossell, David; Morán, Tomás; Ponsa-Cobas, Joan; Auer, Herbert; Corominas, Montserrat; Azorín, Fernando

    2012-10-01

    H3K4me3 is a histone modification that accumulates at the transcription-start site (TSS) of active genes and is known to be important for transcription activation. The way in which H3K4me3 is regulated at TSS and the actual molecular basis of its contribution to transcription remain largely unanswered. To address these questions, we have analyzed the contribution of dKDM5/LID, the main H3K4me3 demethylase in Drosophila, to the regulation of the pattern of H3K4me3. ChIP-seq results show that, at developmental genes, dKDM5/LID localizes at TSS and regulates H3K4me3. dKDM5/LID target genes are highly transcribed and enriched in active RNApol II and H3K36me3, suggesting a positive contribution to transcription. Expression-profiling show that, though weakly, dKDM5/LID target genes are significantly downregulated upon dKDM5/LID depletion. Furthermore, dKDM5/LID depletion results in decreased RNApol II occupancy, particularly by the promoter-proximal Pol llo(ser5) form. Our results also show that ASH2, an evolutionarily conserved factor that locates at TSS and is required for H3K4me3, binds and positively regulates dKDM5/LID target genes. However, dKDM5/LID and ASH2 do not bind simultaneously and recognize different chromatin states, enriched in H3K4me3 and not, respectively. These results indicate that, at developmental genes, dKDM5/LID and ASH2 coordinately regulate H3K4me3 at TSS and that this dynamic regulation contributes to transcription.

  17. Insertion of an imprinted insulator into the IgH locus reveals developmentally regulated, transcription-dependent control of V(D)J recombination.

    PubMed

    Puget, Nadine; Hirasawa, Ryutaro; Hu, Ngoc-Sa Nguyen; Laviolette-Malirat, Nathalie; Feil, Robert; Khamlichi, Ahmed Amine

    2015-02-01

    The assembly of antigen receptor loci requires a developmentally regulated and lineage-specific recombination between variable (V), diversity (D), and joining (J) segments through V(D)J recombination. The process is regulated by accessibility control elements, including promoters, insulators, and enhancers. The IgH locus undergoes two recombination steps, D-J(H) and then V(H)-DJ(H), but it is unclear how the availability of the DJ(H) substrate could influence the subsequent V(H)-DJ(H) recombination step. The Eμ enhancer plays a critical role in V(D)J recombination and controls a set of sense and antisense transcripts. We epigenetically perturbed the early events at the IgH locus by inserting the imprinting control region (ICR) of the Igf2/H19 locus or a transcriptional insulator devoid of the imprinting function upstream of the Eμ enhancer. The insertions recapitulated the main epigenetic features of their endogenous counterparts, including differential DNA methylation and binding of CTCF/cohesins. Whereas the D-J(H) recombination step was unaffected, both the insulator insertions led to a severe impairment of V(H)-DJ(H) recombination. Strikingly, the inhibition of V(H)-DJ(H) recombination correlated consistently with a strong reduction of DJ(H) transcription and incomplete demethylation. Thus, developmentally regulated transcription following D-J(H) recombination emerges as an important mechanism through which the Eμ enhancer controls V(H)-DJ(H) recombination.

  18. Developmental and seed aging mediated regulation of antioxidative genes and differential expression of proteins during pre- and post-germinative phases in pea.

    PubMed

    Yao, Zhen; Liu, Lingwei; Gao, Feng; Rampitsch, Christof; Reinecke, Dennis M; Ozga, Jocelyn A; Ayele, Belay T

    2012-10-15

    Enzymatic antioxidant system plays an important role in maintaining seed vigor and regulating plant growth and development. It involves a number of enzymes that scavenge excessive reactive oxygen species (ROS) produced during seed aging and also modulate the level of these compounds during plant developmental processes. This study investigated the transcriptional regulation of enzymatic antioxidative capacity in pea during the pre- and post-germinative phases and in response to seed aging by analyzing the spatio-temporal expression of five antioxidative genes: PsAPX, PsSOD, PsGRcyt, PsGRcm and PsCAT. Transcripts of all these genes were found in mature dry seeds, embryo axes and cotyledons of germinating seeds, and cotyledons, roots and shoots of young seedlings. However, PsAPX and PsSOD were predominant and exhibited developmental regulation, suggesting that these genes play important roles in controlling the intracellular homeostasis of ROS for promoting cell elongation, and thereby embryo axis expansion and early seedling growth in pea. Accelerated aging of pea seeds led to reduction in seed viability and seedling growth, and this effect was correlated with substantial decrease in the transcriptional activation of the prominent antioxidative genes. Furthermore, our proteomic analysis indicated the association of seed aging with changes in the abundance of specific proteins, revealing additional mechanisms underlying seed aging in pea.

  19. Processes regulating progressive nitrogen limitation under elevated carbon dioxide: a meta-analysis

    NASA Astrophysics Data System (ADS)

    Liang, J.; Qi, X.; Souza, L.; Luo, Y.

    2015-10-01

    Nitrogen (N) cycle has the potential to regulate climate change through its influence on carbon (C) sequestration. Although extensive researches have been done to explore whether or not progressive N limitation (PNL) occurs under CO2 enrichment, a comprehensive assessment of the processes that regulate PNL is still lacking. Here, we quantitatively synthesized the responses of all major processes and pools in terrestrial N cycle with meta-analysis of CO2 experimental data available in the literature. The results showed that CO2 enrichment significantly increased N sequestration in plant and litter pools but not in soil pool. Thus, the basis of PNL occurrence partially exists. However, CO2 enrichment also significantly increased the N influx via biological N fixation, but decreased the N efflux via leaching. In addition, no general diminished CO2 fertilization effect on plant growth over time was observed. Overall, our analyses suggest that the extra N supply by the increased biological N fixation and decreased leaching may potentially alleviate PNL under elevated CO2 conditions. Moreover, our synthesis showed that CO2 enrichment increased soil ammonium (NH4+) but decreased nitrate (NO3-). The different responses of NH4+ and NO3-, and the consequent biological processes, may result in changes in soil microenvironment, community structures and above-belowground interactions, which could potentially affect the terrestrial biogeochemical cycles and the feedback to climate change.

  20. Protein tyrosine phosphatase PTPRB regulates Src phosphorylation and tumour progression in NSCLC.

    PubMed

    Qi, Yinliang; Dai, Yuanchang; Gui, Shuyu

    2016-10-01

    Protein tyrosine-phosphatases (PTPs) play important roles in various biological processes. Deregulation in PTP function has been implicated in carcinogenesis and tumour progression in many cancer types. However, the role of protein tyrosine phosphatase receptor type B (PTPRB) in non-small-cell lung cancer (NSCLC) tumorigenesis has not been investigated. Lentiviral vector expressing PTPRB cDNA or shRNA was infected into A549 and H1299 cell lines, followed by cell proliferation, colony formation, soft agar and invasion assays. A549 xenograft mouse model was used to evaluate in vivo function of PTPRB. Quantitative polymerase chain reaction (PCR) was used to measure PTPRB expression in NSCLC patient samples. Kaplan Meier analysis was performed to assess association between PTPRB expression and patient overall survival (OS). Multivariate analysis was performed to evaluate prognostic significance of PTPRB. Overexpression of PTPRB reduced cell proliferation rate, colony formation efficiency, soft agar growth and cell invasion in A549 and H1299 cells, as well as tumour growth rate in A549 xenograft. Knockdown of PTPRB increased Src phosphorylation and cell invasion, which was reversed by Src inhibitor PP2. Additionally, PTPRB was down-regulated in NSCLC patient and was associated with patient OS. PTPRB regulates Src phosphorylation and tumorigenesis in NSCLC. PTPRB may serve as an independent prognostic biomarker for NSCLC patients.

  1. Regulation of DNA damage responses and cell cycle progression by hMOB2

    PubMed Central

    Gomez, Valenti; Gundogdu, Ramazan; Gomez, Marta; Hoa, Lily; Panchal, Neelam; O’Driscoll, Mark; Hergovich, Alexander

    2014-01-01

    Mps one binder proteins (MOBs) are conserved regulators of essential signalling pathways. Biochemically, human MOB2 (hMOB2) can inhibit NDR kinases by competing with hMOB1 for binding to NDRs. However, biological roles of hMOB2 have remained enigmatic. Here, we describe novel functions of hMOB2 in the DNA damage response (DDR) and cell cycle regulation. hMOB2 promotes DDR signalling, cell survival and cell cycle arrest after exogenously induced DNA damage. Under normal growth conditions in the absence of exogenously induced DNA damage hMOB2 plays a role in preventing the accumulation of endogenous DNA damage and a subsequent p53/p21-dependent G1/S cell cycle arrest. Unexpectedly, these molecular and cellular phenotypes are not observed upon NDR manipulations, indicating that hMOB2 performs these functions independent of NDR signalling. Thus, to gain mechanistic insight, we screened for novel binding partners of hMOB2, revealing that hMOB2 interacts with RAD50, facilitating the recruitment of the MRE11-RAD50-NBS1 (MRN) DNA damage sensor complex and activated ATM to DNA damaged chromatin. Taken together, we conclude that hMOB2 supports the DDR and cell cycle progression. PMID:25460043

  2. Intracellular calcium signals regulate growth of hepatic stellate cells via specific effects on cell cycle progression.

    PubMed

    Soliman, Elwy M; Rodrigues, Michele Angela; Gomes, Dawidson Assis; Sheung, Nina; Yu, Jin; Amaya, Maria Jimina; Nathanson, Michael H; Dranoff, Jonathan A

    2009-03-01

    Hepatic stellate cells (HSC) are important mediators of liver fibrosis. Hormones linked to downstream intracellular Ca(2+) signals upregulate HSC proliferation, but the mechanisms by which this occurs are unknown. Nuclear and cytosolic Ca(2+) signals may have distinct effects on cell proliferation, so we expressed plasmid and adenoviral constructs containing the Ca(2+) chelator parvalbumin (PV) linked to either a nuclear localization sequence (NLS) or a nuclear export sequence (NES) to block Ca(2+) signals in distinct compartments within LX-2 immortalized human HSC and primary rat HSC. PV-NLS and PV-NES constructs each targeted to the appropriate intracellular compartment and blocked Ca(2+) signals only within that compartment. PV-NLS and PV-NES constructs inhibited HSC growth. Furthermore, blockade of nuclear or cytosolic Ca(2+) signals arrested growth at the G2/mitosis (G2/M) cell-cycle interface and prevented the onset of mitosis. Blockade of nuclear or cytosolic Ca(2+) signals downregulated phosphorylation of the G2/M checkpoint phosphatase Cdc25C. Inhibition of calmodulin kinase II (CaMK II) had identical effects on LX-2 growth and Cdc25C phosphorylation. We propose that nuclear and cytosolic Ca(2+) are critical signals that regulate HSC growth at the G2/M checkpoint via CaMK II-mediated regulation of Cdc25C phosphorylation. These data provide a new logical target for pharmacological therapy directed against progression of liver fibrosis.

  3. RPS27a promotes proliferation, regulates cell cycle progression and inhibits apoptosis of leukemia cells

    SciTech Connect

    Wang, Houcai; Yu, Jing; Zhang, Lixia; Xiong, Yuanyuan; Chen, Shuying; Xing, Haiyan; Tian, Zheng; Tang, Kejing; Wei, Hui; Rao, Qing; Wang, Min; Wang, Jianxiang

    2014-04-18

    Highlights: • RPS27a expression was up-regulated in advanced-phase CML and AL patients. • RPS27a knockdown changed biological property of K562 and K562/G01 cells. • RPS27a knockdown affected Raf/MEK/ERK, P21 and BCL-2 signaling pathways. • RPS27a knockdown may be applicable for new combination therapy in CML patients. - Abstract: Ribosomal protein S27a (RPS27a) could perform extra-ribosomal functions besides imparting a role in ribosome biogenesis and post-translational modifications of proteins. The high expression level of RPS27a was reported in solid tumors, and we found that the expression level of RPS27a was up-regulated in advanced-phase chronic myeloid leukemia (CML) and acute leukemia (AL) patients. In this study, we explored the function of RPS27a in leukemia cells by using CML cell line K562 cells and its imatinib resistant cell line K562/G01 cells. It was observed that the expression level of RPS27a was high in K562 cells and even higher in K562/G01 cells. Further analysis revealed that RPS27a knockdown by shRNA in both K562 and K562G01 cells inhibited the cell viability, induced cell cycle arrest at S and G2/M phases and increased cell apoptosis induced by imatinib. Combination of shRNA with imatinib treatment could lead to more cleaved PARP and cleaved caspase-3 expression in RPS27a knockdown cells. Further, it was found that phospho-ERK(p-ERK) and BCL-2 were down-regulated and P21 up-regulated in RPS27a knockdown cells. In conclusion, RPS27a promotes proliferation, regulates cell cycle progression and inhibits apoptosis of leukemia cells. It appears that drugs targeting RPS27a combining with tyrosine kinase inhibitor (TKI) might represent a novel therapy strategy in TKI resistant CML patients.

  4. Hepatic deficiency of the pioneer transcription factor FoxA restricts hepatitis B virus biosynthesis by the developmental regulation of viral DNA methylation

    PubMed Central

    Shalaby, Rasha E.; Iram, Saira; Oropeza, Claudia E.; Landolfi, Jennifer A.; Lyubimov, Alexander V.; Maienschein-Cline, Mark; Kaestner, Klaus H.

    2017-01-01

    The FoxA family of pioneer transcription factors regulates hepatitis B virus (HBV) transcription, and hence viral replication. Hepatocyte-specific FoxA-deficiency in the HBV transgenic mouse model of chronic infection prevents the transcription of the viral DNA genome as a result of the failure of the developmentally controlled conversion of 5-methylcytosine residues to cytosine during postnatal hepatic maturation. These observations suggest that pioneer transcription factors such as FoxA, which mark genes for expression at subsequent developmental steps in the cellular differentiation program, mediate their effects by reversing the DNA methylation status of their target genes to permit their ensuing expression when the appropriate tissue-specific transcription factor combinations arise during development. Furthermore, as the FoxA-deficient HBV transgenic mice are viable, the specific developmental timing, abundance and isoform type of pioneer factor expression must permit all essential liver gene expression to occur at a level sufficient to support adequate liver function. This implies that pioneer transcription factors can recognize and mark their target genes in distinct developmental manners dependent upon, at least in part, the concentration and affinity of FoxA for its binding sites within enhancer and promoter regulatory sequence elements. This selective marking of cellular genes for expression by the FoxA pioneer factor compared to HBV may offer the opportunity for the specific silencing of HBV gene expression and hence the resolution of chronic HBV infections which are responsible for approximately one million deaths worldwide annually due to liver cirrhosis and hepatocellular carcinoma. PMID:28235042

  5. Developmental disorders of vision.

    PubMed

    Galaburda, Albert M; Duchaine, Bradley C

    2003-08-01

    This review of developmental disorders of vision focuses on only a few of the many disorders that disrupt visual development. Given the enormity of the human visual system in the primate brain and complexity of visual development, however, there are likely hundreds or thousands of types of disorders affecting high-level vision. The rapid progress seen in developmental dyslexia and WMS demonstrates the possibilities and difficulties inherent in researching such disorders, and the authors hope that similar progress will be made for congenital prosopagnosia and other disorders in the near future.

  6. Notch pathway regulates female germ cell meiosis progression and early oogenesis events in fetal mouse.

    PubMed

    Feng, Yan-Min; Liang, Gui-Jin; Pan, Bo; Qin, Xun-Si; Zhang, Xi-Feng; Chen, Chun-Lei; Li, Lan; Cheng, Shun-Feng; De Felici, Massimo; Shen, Wei

    2014-01-01

    A critical process of early oogenesis is the entry of mitotic oogonia into meiosis, a cell cycle switch regulated by a complex gene regulatory network. Although Notch pathway is involved in numerous important aspects of oogenesis in invertebrate species, whether it plays roles in early oogenesis events in mammals is unknown. Therefore, the rationale of the present study was to investigate the roles of Notch signaling in crucial processes of early oogenesis, such as meiosis entry and early oocyte growth. Notch receptors and ligands were localized in mouse embryonic female gonads and 2 Notch inhibitors, namely DAPT and L-685,458, were used to attenuate its signaling in an in vitro culture system of ovarian tissues from 12.5 days post coitum (dpc) fetus. The results demonstrated that the expression of Stra8, a master gene for germ cell meiosis, and its stimulation by retinoic acid (RA) were reduced after suppression of Notch signaling, and the other meiotic genes, Dazl, Dmc1, and Rec8, were abolished or markedly decreased. Furthermore, RNAi of Notch1 also markedly inhibited the expression of Stra8 and SCP3 in cultured female germ cells. The increased methylation status of CpG islands within the Stra8 promoter of the oocytes was observed in the presence of DAPT, indicating that Notch signaling is probably necessary for maintaining the epigenetic state of this gene in a way suitable for RA stimulation. Furthermore, in the presence of Notch inhibitors, progression of oocytes through meiosis I was markedly delayed. At later culture periods, the rate of oocyte growth was decreased, which impaired subsequent primordial follicle assembly in cultured ovarian tissues. Taken together, these results suggested new roles of the Notch signaling pathway in female germ cell meiosis progression and early oogenesis events in mammals.

  7. Exposure to Fluorescent Light Triggers Down Regulation of Genes Involved with Mitotic Progression in Xiphophorus Skin

    PubMed Central

    Walter, Ronald B.; Walter, Dylan J.; Boswell, William T.; Caballero, Kaela L.; Boswell, Mikki; Lu, Yuan; Chang, Jordan; Savage, Markita G.

    2015-01-01

    We report RNA-Seq results from skin of X. maculatus Jp 163 B after exposure to various doses of “cool white” fluorescent light (FL). We show that FL exposure incites a genetic transcriptional response in skin nearly as great as observed for UVB exposure; however, the gene sets modulated due to exposure to the two light sources are quite different. Known light responsive genes involved in maintaining circadian cycling (e.g., clock, cry2a, cry1b, per1b, per2, per3, arntl1a, etc.) exhibited expected shifts in transcriptional expression upon FL exposure. Exposure to FL also resulted in down-regulated transcription of many genes involved with cell cycle progression (e.g., cdc20, cdc45, cdca7b, plk1, cdk1, ccnb-3, cdca7a, etc.) and chromosome segregation (e.g., cenpe, cenpf, cenpi, cenpk, cenpo, cenpp, and cenpu; cep70; knstrm, kntc, mcm2, mcm5; smc2, etc.). In addition, several DNA replication and recombination repair genes (e.g., pola1, pole, rec52, rad54l, rpa1, parpbp, etc.) exhibit reduced expression in FL exposed X. maculatus skin. Some genes down modulated by FL are known to be associated with DNA repair and human diseases (e.g., atm2, brip1, fanc1, fancl, xrcc4, etc.). The overall suppression of genes involved with mitotic progression in the skin of adult fish is consistent with entry into the light phase of the circadian cycle. Current efforts are aimed at determining specific wavelengths that may lead to differential expression among the many genes affected by fluorescent light exposure. PMID:26334372

  8. Analysis of a lin-42/period Null Allele Implicates All Three Isoforms in Regulation of Caenorhabditis elegans Molting and Developmental Timing

    PubMed Central

    Edelman, Theresa L. B.; McCulloch, Katherine A.; Barr, Angela; Frøkjær-Jensen, Christian; Jorgensen, Erik M.; Rougvie, Ann E.

    2016-01-01

    The Caenorhabditis elegans heterochronic gene pathway regulates the relative timing of events during postembryonic development. lin-42, the worm homolog of the circadian clock gene, period, is a critical element of this pathway. lin-42 function has been defined by a set of hypomorphic alleles that cause precocious phenotypes, in which later developmental events, such as the terminal differentiation of hypodermal cells, occur too early. A subset of alleles also reveals a significant role for lin-42 in molting; larval stages are lengthened and ecdysis often fails in these mutant animals. lin-42 is a complex locus, encoding overlapping and nonoverlapping isoforms. Although existing alleles that affect subsets of isoforms have illuminated important and distinct roles for this gene in developmental timing, molting, and the decision to enter the alternative dauer state, it is essential to have a null allele to understand all of the roles of lin-42 and its individual isoforms. To remedy this problem and discover the null phenotype, we engineered an allele that deletes the entire lin-42 protein-coding region. lin-42 null mutants are homozygously viable, but have more severe phenotypes than observed in previously characterized hypomorphic alleles. We also provide additional evidence for this conclusion by using the null allele as a base for reintroducing different isoforms, showing that each isoform can provide heterochronic and molting pathway activities. Transcript levels of the nonoverlapping isoforms appear to be under coordinate temporal regulation, despite being driven by independent promoters. The lin-42 null allele will continue to be an important tool for dissecting the functions of lin-42 in molting and developmental timing. PMID:27729432

  9. Analysis of a lin-42/period Null Allele Implicates All Three Isoforms in Regulation of Caenorhabditis elegans Molting and Developmental Timing.

    PubMed

    Edelman, Theresa L B; McCulloch, Katherine A; Barr, Angela; Frøkjær-Jensen, Christian; Jorgensen, Erik M; Rougvie, Ann E

    2016-12-07

    The Caenorhabditis elegans heterochronic gene pathway regulates the relative timing of events during postembryonic development. lin-42, the worm homolog of the circadian clock gene, period, is a critical element of this pathway. lin-42 function has been defined by a set of hypomorphic alleles that cause precocious phenotypes, in which later developmental events, such as the terminal differentiation of hypodermal cells, occur too early. A subset of alleles also reveals a significant role for lin-42 in molting; larval stages are lengthened and ecdysis often fails in these mutant animals. lin-42 is a complex locus, encoding overlapping and nonoverlapping isoforms. Although existing alleles that affect subsets of isoforms have illuminated important and distinct roles for this gene in developmental timing, molting, and the decision to enter the alternative dauer state, it is essential to have a null allele to understand all of the roles of lin-42 and its individual isoforms. To remedy this problem and discover the null phenotype, we engineered an allele that deletes the entire lin-42 protein-coding region. lin-42 null mutants are homozygously viable, but have more severe phenotypes than observed in previously characterized hypomorphic alleles. We also provide additional evidence for this conclusion by using the null allele as a base for reintroducing different isoforms, showing that each isoform can provide heterochronic and molting pathway activities. Transcript levels of the nonoverlapping isoforms appear to be under coordinate temporal regulation, despite being driven by independent promoters. The lin-42 null allele will continue to be an important tool for dissecting the functions of lin-42 in molting and developmental timing.

  10. miR-221/222 control luminal breast cancer tumor progression by regulating different targets.

    PubMed

    Dentelli, Patrizia; Traversa, Matteo; Rosso, Arturo; Togliatto, Gabriele; Olgasi, Cristina; Marchiò, Caterina; Provero, Paolo; Lembo, Antonio; Bon, Giulia; Annaratone, Laura; Sapino, Anna; Falcioni, Rita; Brizzi, Maria Felice

    2014-01-01

    α6β4 integrin is an adhesion molecule for laminin receptors involved in tumor progression. We present a link between β4 integrin expression and miR-221/222 in the most prevalent human mammary tumor: luminal invasive carcinomas (Lum-ICs). Using human primary tumors that display different β4 integrin expression and grade, we show that miR-221/222 expression inversely correlates with tumor proliferating index, Ki67. Interestingly, most high-grade tumors express β4 integrin and low miR-221/222 levels. We ectopically transfected miR-221/222 into a human-derived mammary tumor cell line that recapitulates the luminal subtype to investigate whether miR-221/222 regulates β4 expression. We demonstrate that miR-221/222 overexpression results in β4 expression downregulation, breast cancer cell proliferation, and invasion inhibition. The role of miR-221/222 in driving β4 integrin expression is also confirmed via mutating the miR-221/222 seed sequence for β4 integrin 3'UTR. Furthermore, we show that these 2 miRNAs are also key breast cancer cell proliferation and invasion regulators, via the post-transcriptional regulation of signal transducer and activator of transcription 5A (STAT5A) and of a disintegrin and metalloprotease-17 (ADAM-17). We further confirm these data by silencing ADAM-17, using a dominant-negative or an activated STAT5A form. miR-221/222-driven β4 integrin, STAT5A, and ADAM-17 did not occur in MCF-10A cells, denoted "normal" breast epithelial cells, indicating that the mechanism is cancer cell-specific.   These results provide the first evidence of a post-transcriptional mechanism that regulates β4 integrin, STAT5A, and ADAM-17 expression, thus controlling breast cancer cell proliferation and invasion. Pre-miR-221/222 use in the aggressive luminal subtype may be a powerful therapeutic anti-cancer strategy.

  11. Contrasting evolutionary dynamics of the developmental regulator PAX9, among bats, with evidence for a novel post-transcriptional regulatory mechanism.

    PubMed

    Phillips, Caleb D; Butler, Boyd; Fondon, John W; Mantilla-Meluk, Hugo; Baker, Robert J

    2013-01-01

    Morphological evolution can be the result of natural selection favoring modification of developmental signaling pathways. However, little is known about the genetic basis of such phenotypic diversity. Understanding these mechanisms is difficult for numerous reasons, yet studies in model organisms often provide clues about the major developmental pathways involved. The paired-domain gene, PAX9, is known to be a key regulator of development, particularly of the face and teeth. In this study, using a comparative genetics approach, we investigate PAX9 molecular evolution among mammals, focusing on craniofacially diversified (Phyllostomidae) and conserved (Vespertilionidae) bat families, and extend our comparison to other orders of mammal. Open-reading frame analysis disclosed signatures of selection, in which a small percentage of residues vary, and lineages acquire different combinations of variation through recurrent substitution and lineage specific changes. A few instances of convergence for specific residues were observed between morphologically convergent bat lineages. Bioinformatic analysis for unknown PAX9 regulatory motifs indicated a novel post-transcriptional regulatory mechanism involving a Musashi protein. This regulation was assessed through fluorescent reporter assays and gene knockdowns. Results are compatible with the hypothesis that the number of Musashi binding-elements in PAX9 mRNA proportionally regulates protein translation rate. Although a connection between morphology and binding element frequency was not apparent, results indicate this regulation would vary among craniofacially divergent bat species, but be static among conserved species. Under this model, Musashi's regulatory control of alternative human PAX9 isoforms would also vary. The presence of Musashi-binding elements within PAX9 of all mammals examined, chicken, zebrafish, and the fly homolog of PAX9, indicates this regulatory mechanism is ancient, originating basal to much of the

  12. Developmental Screening

    MedlinePlus

    Learn More about Your Child’s Development: Developmental Monitoring and Screening Taking a first step, waving “bye-bye,” and pointing to something interesting are all developmental milestones, ...

  13. Developmental Toxicity

    EPA Science Inventory

    This chapter provides an overview the developmental toxicity resulting from exposure to perfluorinated alkyl acids (PFAAs). The majority of studies of PFAA-induced developmental toxicity have examined effects of perfluorooctane sulfonate (PFOS) or perfluorooctanoic acid (PFOA) a...

  14. Processes regulating progressive nitrogen limitation under elevated carbon dioxide: a meta-analysis

    NASA Astrophysics Data System (ADS)

    Liang, Junyi; Qi, Xuan; Souza, Lara; Luo, Yiqi

    2016-05-01

    The nitrogen (N) cycle has the potential to regulate climate change through its influence on carbon (C) sequestration. Although extensive research has explored whether or not progressive N limitation (PNL) occurs under CO2 enrichment, a comprehensive assessment of the processes that regulate PNL is still lacking. Here, we quantitatively synthesized the responses of all major processes and pools in the terrestrial N cycle with meta-analysis of CO2 experimental data available in the literature. The results showed that CO2 enrichment significantly increased N sequestration in the plant and litter pools but not in the soil pool, partially supporting one of the basic assumptions in the PNL hypothesis that elevated CO2 results in more N sequestered in organic pools. However, CO2 enrichment significantly increased the N influx via biological N fixation and the loss via N2O emission, but decreased the N efflux via leaching. In addition, no general diminished CO2 fertilization effect on plant growth was observed over time up to the longest experiment of 13 years. Overall, our analyses suggest that the extra N supply by the increased biological N fixation and decreased leaching may potentially alleviate PNL under elevated CO2 conditions in spite of the increases in plant N sequestration and N2O emission. Moreover, our syntheses indicate that CO2 enrichment increases soil ammonium (NH4+) to nitrate (NO3-) ratio. The changed NH4+/NO3- ratio and subsequent biological processes may result in changes in soil microenvironments, above-belowground community structures and associated interactions, which could potentially affect the terrestrial biogeochemical cycles. In addition, our data synthesis suggests that more long-term studies, especially in regions other than temperate ones, are needed for comprehensive assessments of the PNL hypothesis.

  15. Processes regulating progressive nitrogen limitation under elevated carbon dioxide: a meta-analysis

    DOE PAGES

    Liang, Junyi; Qi, Xuan; Souza, Lara; ...

    2016-05-10

    The nitrogen (N) cycle has the potential to regulate climate change through its influence on carbon (C) sequestration. Although extensive research has explored whether or not progressive N limitation (PNL) occurs under CO2 enrichment, a comprehensive assessment of the processes that regulate PNL is still lacking. Here, we quantitatively synthesized the responses of all major processes and pools in the terrestrial N cycle with meta-analysis of CO2 experimental data available in the literature. The results showed that CO2 enrichment significantly increased N sequestration in the plant and litter pools but not in the soil pool, partially supporting one of themore » basic assumptions in the PNL hypothesis that elevated CO2 results in more N sequestered in organic pools. However, CO2 enrichment significantly increased the N influx via biological N fixation and the loss via N2O emission, but decreased the N efflux via leaching. In addition, no general diminished CO2 fertilization effect on plant growth was observed over time up to the longest experiment of 13 years. Overall, our analyses suggest that the extra N supply by the increased biological N fixation and decreased leaching may potentially alleviate PNL under elevated CO2 conditions in spite of the increases in plant N sequestration and N2O emission. Moreover, our syntheses indicate that CO2 enrichment increases soil ammonium (NH4+) to nitrate (NO3−) ratio. The changed NH4+/NO3− ratio and subsequent biological processes may result in changes in soil microenvironments, above-belowground community structures and associated interactions, which could potentially affect the terrestrial biogeochemical cycles. In addition, our data synthesis suggests that more long-term studies, especially in regions other than temperate ones, are needed for comprehensive assessments of the PNL hypothesis.« less

  16. [Developmental dyslexia].

    PubMed

    Galaburda, A M; Cestnick, L

    2003-02-01

    Developmental dyslexia makes up an important proportion of the known learning disorders. Until the late 1970s most research on dyslexia was carried out by educators and educational psychologists, but soon after the publication of some dyslexic cases with focal disorders of neuronal migration to the cerebral cortex, interest in the neurobiological and neurocognitive underpinnings of dyslexia grew, especially in Europe and North America. There are at least two types of developmental dyslexia--phonological and surface. Surface dyslexia refers to a disorder in which the difficulty lies in reading irregular words, whereas phonological dyslexia is characterized by difficulty with pseudowords. Phonological dyslexia is the more common of the two types. Surface dyslexia does not present a major problem in a language such as Spanish, where the number of irregular words is indeed very small. Still, in languages such as English, where irregular words are common, the phonological type of developmental dyslexia is much more common. Phonologic dyslexics have problems with phonological awareness, that is, the conscious knowledge and manipulation of speech sounds, which is the most proximate explanation for their difficulty in reading pseudowords. Many, but not all, phonologic dyslexics also have problems processing rapidly changing sounds, even if not linguistic, and some slow sounds, too. The same group tends to have visual problems, especially involving the so-called magnocellular pathway of the visual system, which, among others, has the role of analyzing movement. Accompanying these perceptual and cognitive deficits, phonologic dyslexics also show abnormal brain activation to phonological tasks, as shown in functional magnetic resonance studies (figure). In addition, dyslexic brains show focal malformations, ectopias and microgyria, of the cerebral cortex, involving mainly the left perisylvian region and the word form area in the temporo-occipital junction. There are also

  17. Gestational lead exposure induces developmental abnormalities and up-regulates apoptosis of fetal cerebellar cells in rats.

    PubMed

    Mousa, Alyaa M; Al-Fadhli, Ameera S; Rao, Muddanna S; Kilarkaje, Narayana

    2015-01-01

    Lead (Pb), a known environmental toxicant, adversely affects almost all organ systems. In this study, we investigated the effects of maternal lead exposure on fetal rat cerebellum. Female Sprague-Dawley rats were given lead nitrate in drinking water (0, 0.5, and 1%) for two weeks before conception, and during pregnancy. Fetuses were collected by caesarian section on gestational day 21 and observed for developmental abnormalities. The fetal cerebellar sections from control and 1% lead group were stained with cresyl violet. Immunohistochemical expressions of p53, Bax, Bcl-2, and caspase 3 were quantified by AnalySIS image analyzer (Life Science, Germany). Lead exposure induced developmental abnormalities of eyes, ear, limbs, neck and ventral abdominal wall; however, these abnormalities were commonly seen in the 1% lead-treated group. In addition, lead also caused fetal mortality and reduced body growth in both dose groups and reduced brain weight in the 1% lead-treated group. The fetal cerebella from the 1% lead-treated group showed unorganized cerebellar cortical layers, and degenerative changes in granule and Purkinje cells such as the formation of clumps of Nissl granules. An increase in Bax and caspase 3, and a decrease in Bcl-2 (p < 0.05), but not in p53, showed apoptosis of the neurons. In conclusion, gestational lead exposure in rats induces fetal toxicity and developmental abnormalities. The lead exposure also impairs development of cerebellar layers, induces structural changes, and apoptosis in the fetal cerebellar cortex. These results suggest that lead exposure during gestation is extremely toxic to developing cerebellum in rats.

  18. Kif2a regulates spindle organization and cell cycle progression in meiotic oocytes

    PubMed Central

    Yi, Zi-Yun; Ma, Xue-Shan; Liang, Qiu-Xia; Zhang, Teng; Xu, Zhao-Yang; Meng, Tie-Gang; Ouyang, Ying-Chun; Hou, Yi; Schatten, Heide; Sun, Qing-Yuan; Quan, Song

    2016-01-01

    Kif2a is a member of the Kinesin-13 microtubule depolymerases. Here, we report the expression, subcellular localization and functions of Kif2a during mouse oocyte meiotic maturation. Immunoblotting analysis showed that Kif2a was gradually increased form GV to the M I stages, and then decreased slightly at the M II stage. Confocal microscopy identified that Kif2a localized to the meiotic spindle, especially concentrated at the spindle poles and inner centromeres in metaphase and translocated to the midbody at telophase. Kif2a depletion by siRNA microinjection generated severely defective spindles and misaligned chromosomes, reduced microtubule depolymerization, which led to significant pro-M I/M Iarrest and failure of first polar body (PB1) extrusion. Kif2a-depleted oocytes were also defective in spindle pole localization of γ-tubulin and showed spindle assembly checkpoint (SAC) protein Bub3 at the kinetochores even after 10 hr extended culture. These results demonstrate that Kif2a may act as a microtubule depolymerase, regulating microtubule dynamics, spindle assembly and chromosome congression, and thus cell cycle progression during mouse oocyte meiotic maturation. PMID:27991495

  19. Neurogenin 2 regulates progenitor cell-cycle progression and Purkinje cell dendritogenesis in cerebellar development.

    PubMed

    Florio, Marta; Leto, Ketty; Muzio, Luca; Tinterri, Andrea; Badaloni, Aurora; Croci, Laura; Zordan, Paola; Barili, Valeria; Albieri, Ilaria; Guillemot, François; Rossi, Ferdinando; Consalez, G Giacomo

    2012-07-01

    By serving as the sole output of the cerebellar cortex, integrating a myriad of afferent stimuli, Purkinje cells (PCs) constitute the principal neuron in cerebellar circuits. Several neurodegenerative cerebellar ataxias feature a selective cell-autonomous loss of PCs, warranting the development of regenerative strategies. To date, very little is known as to the regulatory cascades controlling PC development. During central nervous system development, the proneural gene neurogenin 2 (Neurog2) contributes to many distinct neuronal types by specifying their fate and/or dictating development of their morphological features. By analyzing a mouse knock-in line expressing Cre recombinase under the control of Neurog2 cis-acting sequences we show that, in the cerebellar primordium, Neurog2 is expressed by cycling progenitors cell-autonomously fated to become PCs, even when transplanted heterochronically. During cerebellar development, Neurog2 is expressed in G1 phase by progenitors poised to exit the cell cycle. We demonstrate that, in the absence of Neurog2, both cell-cycle progression and neuronal output are significantly affected, leading to an overall reduction of the mature cerebellar volume. Although PC fate identity is correctly specified, the maturation of their dendritic arbor is severely affected in the absence of Neurog2, as null PCs develop stunted and poorly branched dendrites, a defect evident from the early stages of dendritogenesis. Thus, Neurog2 represents a key regulator of PC development and maturation.

  20. Molecular Profiling of Human Induced Pluripotent Stem Cell-Derived Hypothalamic Neurones Provides Developmental Insights into Genetic Loci for Body Weight Regulation.

    PubMed

    Yao, L; Liu, Y; Qiu, Z; Kumar, S; Curran, J E; Blangero, J; Chen, Y; Lehman, D M

    2017-02-01

    Recent data suggest that common genetic risks for metabolic disorders such as obesity may be human-specific and exert effects via the central nervous system. To overcome the limitation of human tissue access for study, we have generated induced human pluripotent stem cell (hiPSC)-derived neuronal cultures that recapture many features of hypothalamic neurones within the arcuate nucleus. In the present study, we have comprehensively characterised this model across development, benchmarked these neurones to in vivo events, and demonstrate a link between obesity risk variants and hypothalamic development. The dynamic transcriptome across neuronal maturation was examined using microarray and RNA sequencing methods at nine time points. K-means clustering of the longitudinal data was conducted to identify co-regulation and microRNA control of biological processes. The transcriptomes were compared with those of 103 samples from 13 brain regions reported in the Genotype-Tissue Expression database (GTEx) using principal components analysis. Genes with proximity to body mass index (BMI)-associated genetic variants were mapped to the developmentally expressed genesets, and enrichment significance was assessed with Fisher's exact test. The human neuronal cultures have a transcriptional and physiological profile of neuropeptide Y/agouti-related peptide arcuate nucleus neurones. The neuronal transcriptomes were highly correlated with adult hypothalamus compared to any other brain region from the GTEx. Also, approximately 25% of the transcripts showed substantial changes in expression across neuronal development and potential co-regulation of biological processes that mirror neuronal development in vivo. These developmentally expressed genes were significantly enriched for genes in proximity to BMI-associated variants. We confirmed the utility of this in vitro human model for studying the development of key hypothalamic neurones involved in energy balance and show that genes at

  1. Developmental monitoring in primary care.

    PubMed Central

    Goldfarb, C. E.; Roberts, W.

    1996-01-01

    Monitoring child development is an essential part of primary health care. Successful surveillance depends on physicians' thorough knowledge of normal progress along the four developmental streams: motor, language, cognitive, and social and emotional. Being alert to "red flags" that suggest problems is important. Effective interventions can minimize developmental problems. PMID:8792021

  2. AP-1 Is a Key Regulator of Proinflammatory Cytokine TNFα-mediated Triple-negative Breast Cancer Progression*

    PubMed Central

    Qiao, Yichun; He, Huan; Jonsson, Philip; Sinha, Indranil; Zhao, Chunyan; Dahlman-Wright, Karin

    2016-01-01

    Triple-negative breast cancer (TNBC) represents a highly aggressive form of breast cancer with limited treatment options. Proinflammatory cytokines such as TNFα can facilitate tumor progression and metastasis. However, the mechanistic aspects of inflammation mediated TNBC progression remain unclear. Using ChIP-seq, we demonstrate that the cistrome for the AP-1 transcription factor c-Jun is comprised of 13,800 binding regions in TNFα-stimulated TNBC cells. In addition, we show that c-Jun regulates nearly a third of the TNFα-regulated transcriptome. Interestingly, high expression level of the c-Jun-regulated pro-invasion gene program is associated with poor clinical outcome in TNBCs. We further demonstrate that c-Jun drives TNFα-mediated increase of malignant characteristics of TNBC cells by transcriptional regulation of Ninj1. As exemplified by the CXC chemokine genes clustered on chromosome 4, we demonstrate that NF-κB might be a pioneer factor required for the regulation of TNFα-inducible inflammatory genes, whereas c-Jun has little effect. Together, our results uncover AP-1 as an important determinant for inflammation-induced cancer progression, rather than inflammatory response. PMID:26792858

  3. Systems Modeling in Developmental Toxicity

    EPA Science Inventory

    An individual starts off as a single cell, the progeny of which form complex structures that are themselves integrated into progressively larger systems. Developmental biology is concerned with how this cellular complexity and patterning arises through orchestration of cell divi...

  4. Distinct and developmentally regulated activity-dependent plasticity at descending glutamatergic synapses on flexor and extensor motoneurons

    PubMed Central

    Lenschow, Constanze; Cazalets, Jean-René; Bertrand, Sandrine S.

    2016-01-01

    Activity-dependent synaptic plasticity (ADSP) is paramount to synaptic processing and maturation. However, identifying the ADSP capabilities of the numerous synapses converging onto spinal motoneurons (MNs) remain elusive. Using spinal cord slices from mice at two developmental stages, 1–4 and 8–12 postnatal days (P1–P4; P8–P12), we found that high-frequency stimulation of presumed reticulospinal neuron axons in the ventrolateral funiculus (VLF) induced either an NMDA receptor-dependent-long-term depression (LTD), a short-term depression (STD) or no synaptic modulation in limb MNs. Our study shows that P1–P4 cervical MNs expressed the same plasticity profiles as P8–P12 lumbar MNs rather than P1–P4 lumbar MNs indicating that ADSP expression at VLF-MN synapses is linked to the rostrocaudal development of spinal motor circuitry. Interestingly, we observed that the ADSP expressed at VLF-MN was related to the functional flexor or extensor MN subtype. Moreover, heterosynaptic plasticity was triggered in MNs by VLF axon tetanisation at neighbouring synapses not directly involved in the plasticity induction. ADSP at VLF-MN synapses specify differential integrative synaptic processing by flexor and extensor MNs and could contribute to the maturation of spinal motor circuits and developmental acquisition of weight-bearing locomotion. PMID:27329279

  5. Regulation of the seed to seedling developmental phase transition by the LAFL and VAL transcription factor networks

    PubMed Central

    Jia, Haiyan; Suzuki, Masaharu; McCarty, Donald R

    2014-01-01

    In the seed, a fundamental transition between embryo and vegetative phases of plant development is coordinated by the interaction between the AFL and VAL sub-clades of the plant specific B3 domain transcription factor family. The AFL B3 factors together with LEC1-type HAP3 transcription factors promote embryo maturation; whereas the VAL B3 factors repress the LEC1/AFL (LAFL) network during seed germination. Recent advances reveal that genes in key developmental programs and hormone signaling pathways are downstream targets of the LAFL network highlighting the central role of the LAFL network in integration of intrinsic developmental and hormonal signals during plant development. The VAL B3 proteins are proposed to mediate repression by recruiting a histone deacetylase complex (HDAC) to LAFL genes that contain the Sph/RY cis-element recognized by AFL and VAL B3-DNA-binding domains. In addition to VAL B3 factors, epigenetic mechanisms are implicated in maintaining repression of LAFL network during vegetative development. WIREs Dev Biol 2014, 3:135–145. doi: 10.1002/wdev.126 PMID:24902838

  6. Developmental and stress regulation of gene expression for a 9-cis-epoxycarotenoid dioxygenase, CstNCED, isolated from Crocus sativus stigmas.

    PubMed

    Ahrazem, Oussama; Rubio-Moraga, Angela; Trapero, Almudena; Gómez-Gómez, Lourdes

    2012-01-01

    Oxidative cleavage of cis-epoxycarotenoids by 9-cis-epoxycarotenoid dioxygenase (NCED) is the critical step in the regulation of abscisic acid (ABA) synthesis in higher plants. ABA has been associated with dormancy and flower senescence, while also regulating plant adaptive responses to various environmental stresses. An NCED gene, CstNCED, was cloned from Crocus sativus stigmas. The deduced amino acid sequence of the CstNCED protein shared high identity with other monocot NCEDs, and was closely related to the liliopsida enzymes. At the N-terminus of CstNCED a chloroplast transit peptide sequence is located. However, its expression in chloroplast-free tissues suggested localization in other plastid types. The relationship between expression of CstNCED and the endogenous ABA level was investigated in the stigma and corms, where it was developmentally regulated. The senescence of the unpollinated stigma is preceded by an increase in ABA levels and CstNCED expression. In corms, a correlation was observed between CstNCED expression and dormancy. Furthermore, CstNCED expression was correlated with the presence of zeaxanthin in the dormant corms. When detached C. sativus leaves and stigmas were water and salt stressed, increases in CstNCED mRNA were observed. The results provided evidence of the involvement of CstNCED in the regulation of ABA-associated processes such as flower senescence and corm dormancy in monocotyledonous saffron.

  7. Emotional Self-Regulation, Peer Rejection, and Antisocial Behavior: Developmental Associations from Early Childhood to Early Adolescence

    ERIC Educational Resources Information Center

    Trentacosta, Christopher J.; Shaw, Daniel S.

    2009-01-01

    This study examined relations among emotional self-regulation, peer rejection, and antisocial behavior in a sample of 122 boys from low-income families who participated in a summer camp and were followed longitudinally from early childhood to early adolescence. Emotional self-regulation strategies were coded in early childhood from a waiting task,…

  8. The Developmental Trajectory of Perceived Self-Regulation, Personal Interest, and General Achievement throughout High School: A Longitudinal Study

    ERIC Educational Resources Information Center

    Helle, Laura; Laakkonen, Eero; Tuijula, Tiina; Vermunt, Jan D.

    2013-01-01

    Background: Our interest in perceived self-regulation of learning arose in the context of educational reform. After decades of stability, the Finnish high school system underwent reform in the 1990s, with a significant emphasis being placed on promoting student self-regulation of learning. Aims: The purposes of the study were (1) to evaluate…

  9. Developmentally regulated Ca2+-dependent activator protein for secretion 2 (CAPS2) is involved in BDNF secretion and is associated with autism susceptibility.

    PubMed

    Sadakata, Tetsushi; Furuichi, Teiichi

    2009-09-01

    The postnatal development of the cerebellum is accomplished via a series of cytogenetic and morphogenetic events encoded in the genome. To decipher the underlying genetic basis of these events we have systematized the spatio-temporal gene expression profiles during mouse cerebellar development in the Cerebellar Development Transcriptome Database (CDT-DB). Using the CDT-DB, Ca(2+)-dependent activator protein for secretion 2 (CAPS2 or CADPS2) was identified as a developmentally regulated gene that is predominantly expressed in cerebellar granule cells (GCs) with an expression peak around the first or second postnatal week. CAPS2 protein is concentrated in parallel fiber (PF) terminals and is associated with secretory vesicles containing brain-derived neurotrophic factor (BDNF) and neurotrophin-3 (NT-3). CAPS2 enhances release of BDNF and NT-3, both of which are essential for normal cerebellar development. CAPS2-deficient (CAPS2(-/-)) mice show reduced secretion of BDNF and NT-3; consequently, the cerebella of these mice exhibit developmental deficits, such as delayed development and increased cell death in GCs, fewer branched dendrites on Purkinje cells (PCs), and loss of the intercrural fissure. The PF-PC synapses have aberrant cytoarchitectures and electrophysiological properties. These abnormal cellular and morphological phenotypes are more severe around the cerebellar vermis, in which hypoplasia has been reported in autism patients. Moreover, CAPS2(-/-) mice had fewer cortical and hippocampal parvalbumin-positive interneurons and some autistic-like behavioral phenotypes. In the CAPS2 genes of some autistic patients an aberrant splicing variant and non-synonymous SNPs have been identified. These recent studies implicate CAPS2 in autism susceptibility. Therefore, CAPS2(-/-) mice will be a useful model animal in which to study aspects of the neuropathology and behaviors characteristic of developmental disorders.

  10. Evidence for Regulation of Mitotic Progression through Temporal Phosphorylation and Dephosphorylation of CK2α▿ †

    PubMed Central

    St-Denis, Nicole A.; Derksen, D. Richard; Litchfield, David W.

    2009-01-01

    Proper mitotic progression is crucial for maintenance of genomic integrity in proliferating cells and is regulated through an intricate series of events, including protein phosphorylation governed by a complex network of protein kinases. One kinase family implicated in the regulation of mitotic progression is protein kinase CK2, a small family of enzymes that is overexpressed in cancer and induces transformation in mice and cultured fibroblasts. CK2α, one isoform of the catalytic subunits of CK2, is maximally phosphorylated at four sites in nocodazole-treated cells. To investigate the effects of CK2α phosphorylation on mitotic progression, we generated phosphospecific antibodies against its mitotic phosphorylation sites. In U2OS cells released from S-phase arrest, these antibodies reveal that CK2α is most highly phosphorylated in prophase and metaphase. Phosphorylation gradually decreases during anaphase and becomes undetectable during telophase and cytokinesis. Stable expression of phosphomimetic CK2α (CK2α-4D, CK2α-4E) results in aberrant centrosome amplification and chromosomal segregation defects and loss of mitotic cells through mitotic catastrophe. Conversely, cells expressing nonphosphorylatable CK2α (CK2α-4A) show a decreased ability to arrest in mitosis following nocodazole treatment, suggesting involvement in the spindle assembly checkpoint. Collectively, these studies indicate that reversible phosphorylation of CK2α requires precise regulation to allow proper mitotic progression. PMID:19188443

  11. Regulation of cell division cycle progression by bcl-2 expression: a potential mechanism for inhibition of programmed cell death

    PubMed Central

    1996-01-01

    Expression of the bcl-2 gene has been shown to effectively confer resistance to programmed cell death under a variety of circumstances. However, despite a wealth of literature describing this phenomenon, very little is known about the mechanism of resistance. In the experiments described here, we show that bcl-2 gene expression can result in an inhibition of cell division cycle progression. These findings are based upon the analysis of cell cycle distribution, cell cycle kinetics, and relative phosphorylation of the retinoblastoma tumor suppressor protein, using primary tissues in vivo, ex vivo, and in vitro, as well as continuous cell lines. The effects of bcl-2 expression on cell cycle progression appear to be focused at the G1 to S phase transition, which is a critical control point in the decision between continued cell cycle progression or the induction programmed cell death. In all systems tested, bcl-2 expression resulted in a substantial 30-60% increase in the length of G1 phase; such an increase is very substantial in the context of other regulators of cell cycle progression. Based upon our findings, and the related findings of others, we propose a mechanism by which bcl-2 expression might exert its well known inhibition of programmed cell death by regulating the kinetics of cell cycle progression at a critical control point. PMID:8642331

  12. Developmental regulation of the effects of fibroblast growth factor-2 and 1-octanol on neuronogenesis: implications for a hypothesis relating to mitogen-antimitogen opposition

    NASA Technical Reports Server (NTRS)

    Goto, T.; Takahashi, T.; Miyama, S.; Nowakowski, R. S.; Bhide, P. G.; Caviness, V. S. Jr

    2002-01-01

    Neocortical neurons arise from a pseudostratified ventricular epithelium (PVE) that lies within the ventricular zone (VZ) at the margins of the embryonic cerebral ventricles. We examined the effects of fibroblast growth factor-2 (FGF-2) and 1-octanol on cell output behavior of the PVE in explants of the embryonic mouse cerebral wall. FGF-2 is mitogenic and 1-octanol antimitogenic in the PVE. Whereas all postmitotic cells migrate out of the VZ in vivo, in the explants some postmitotic cells remain within the VZ. We refer to these cells as the indeterminate or I fraction, because they neither exit from the VZ nor reenter S phase as part of the proliferative (P) fraction. They are considered to be either in an extremely prolonged G(1) phase, unable to pass the G(1)/S transition, or in the G(0) state. The I fate choice is modulated by both FGF-2 and 1-octanol. FGF-2 decreased the I fraction and increased the P fraction. In contrast, 1-octanol increased the I fraction and nearly eliminated the P fraction. The effects of FGF-2 and 1-octanol were developmentally regulated, in that they were observed in the developmentally advanced lateral region of the cerebral wall but not in the medial region. Copyright 2002 Wiley-Liss, Inc.

  13. Systems Analysis of a Maize Leaf Developmental Gradient Redefines the Current C4 Model and Provides Candidates for Regulation[W][OA

    PubMed Central

    Pick, Thea R.; Bräutigam, Andrea; Schlüter, Urte; Denton, Alisandra K.; Colmsee, Christian; Scholz, Uwe; Fahnenstich, Holger; Pieruschka, Roland; Rascher, Uwe; Sonnewald, Uwe; Weber, Andreas P.M.

    2011-01-01

    We systematically analyzed a developmental gradient of the third maize (Zea mays) leaf from the point of emergence into the light to the tip in 10 continuous leaf slices to study organ development and physiological and biochemical functions. Transcriptome analysis, oxygen sensitivity of photosynthesis, and photosynthetic rate measurements showed that the maize leaf undergoes a sink-to-source transition without an intermediate phase of C3 photosynthesis or operation of a photorespiratory carbon pump. Metabolome and transcriptome analysis, chlorophyll and protein measurements, as well as dry weight determination, showed continuous gradients for all analyzed items. The absence of binary on–off switches and regulons pointed to a morphogradient along the leaf as the determining factor of developmental stage. Analysis of transcription factors for differential expression along the leaf gradient defined a list of putative regulators orchestrating the sink-to-source transition and establishment of C4 photosynthesis. Finally, transcriptome and metabolome analysis, as well as enzyme activity measurements, and absolute quantification of selected metabolites revised the current model of maize C4 photosynthesis. All data sets are included within the publication to serve as a resource for maize leaf systems biology. PMID:22186372

  14. Hormonally up-regulated neu-associated kinase: A novel target for breast cancer progression.

    PubMed

    Zambrano, Joelle N; Neely, Benjamin A; Yeh, Elizabeth S

    2017-02-09

    Hormonally up-regulated neu-associated Kinase (Hunk) is a protein kinase that was originally identified in the murine mammary gland and has been shown to be highly expressed in Human Epidermal Growth Factor Receptor 2 positive (HER2(+)/ErbB2(+)) breast cancer cell lines as well as MMTV-neu derived mammary tumor cell lines. However, the physiological role of Hunk has been largely elusive since its identification. Though Hunk is predicted to be a Serine/Threonine (Ser/Thr) protein kinase with homology to the SNF1/AMPK family of protein kinases, there are no known Hunk substrates that have been identified to date. Recent work demonstrates a role for Hunk in HER2(+)/ErbB2(+) breast cancer progression, including drug resistance to HER2/ErbB2 inhibitors, with Hunk potentially acting downstream of HER2/ErbB2 and the PI3K/Akt pathway. These studies have collectively shown that Hunk plays a vital role in promoting mammary tumorigenesis, as Hunk knockdown via shRNA in xenograft tumor models or crossing MMTV-neu or Pten-deficient genetically engineered mouse models into a Hunk knockout (Hunk-/-) background impairs mammary tumor growth in vivo. Because the majority of HER2(+)/ErbB2(+) breast cancer patients acquire drug resistance to HER2/ErbB2 inhibitors, the characterization of novel drug targets like Hunk that have the potential to simultaneously suppress tumorigenesis and potentially enhance efficacy of current therapeutics is an important facet of drug development. Therefore, work aimed at uncovering specific regulatory functions for Hunk that could contribute to this protein kinase's role in both tumorigenesis and drug resistance will be informative. This review focuses on what is currently known about this under-studied protein kinase, and how targeting Hunk may prove to be a potential therapeutic target for the treatment of breast cancer.

  15. Regulator of G protein signaling 6 is a novel suppressor of breast tumor initiation and progression

    PubMed Central

    Fisher, Rory A.

    2013-01-01

    Breast cancer is a large global health burden and the most frequently diagnosed malignancy in women worldwide. Here, we utilize RGS6− /− mice to interrogate the role of regulator of G protein signaling 6 (RGS6), localized to the ductal epithelium in mouse and human breast, as a novel tumor suppressor in vivo. RGS6− /− mice exhibit accelerated 7,12-dimethylbenza[α]anthracene (DMBA)-induced tumor initiation and progression, as well as decreased overall survival. Analysis of carcinogenic aberrations in the mammary glands of DMBA-treated mice revealed a failure of the DNA damage response concurrent with augmented oncogenesis in RGS6−/− animals. Furthermore, RGS6 suppressed cell growth induced by either human epidermal growth factor receptor 2 or estrogen receptor activation in both MCF-7 breast cancer cells and mammary epithelial cells (MECs). MECs isolated from RGS6−/− mice also showed a deficit in DMBA-induced ATM/p53 activation, reactive oxygen species generation and apoptosis confirming that RGS6 is required for effective activation of the DNA damage response in these cells, a critical countermeasure against carcinogen-mediated genotoxic stress. The ability of RGS6 to simultaneously enhance DNA-damage-induced apoptotic signaling and suppress oncogenic cell growth likely underlie the accelerated tumorigenesis and cellular transformation observed in DMBA-treated RGS6−/− mice and isolated MECs, respectively. Unsurprisingly, spontaneous tumor formation was also seen in old female RGS6−/− but not in wild-type mice. Our finding that RGS6 is downregulated in all human breast cancer subtypes independent of their molecular classification indicates that obtaining a means to restore the growth suppressive and pro-apoptotic actions of RGS6 in breast might be a viable means to treat a large spectrum of breast tumors. PMID:23598467

  16. Regulator of G protein signaling 6 is a novel suppressor of breast tumor initiation and progression.

    PubMed

    Maity, Biswanath; Stewart, Adele; O'Malley, Yunxia; Askeland, Ryan W; Sugg, Sonia L; Fisher, Rory A

    2013-08-01

    Breast cancer is a large global health burden and the most frequently diagnosed malignancy in women worldwide. Here, we utilize RGS6(-/-) mice to interrogate the role of regulator of G protein signaling 6 (RGS6), localized to the ductal epithelium in mouse and human breast, as a novel tumor suppressor in vivo. RGS6(-/-) mice exhibit accelerated 7,12-dimethylbenza[α]anthracene (DMBA)-induced tumor initiation and progression, as well as decreased overall survival. Analysis of carcinogenic aberrations in the mammary glands of DMBA-treated mice revealed a failure of the DNA damage response concurrent with augmented oncogenesis in RGS6(-/-) animals. Furthermore, RGS6 suppressed cell growth induced by either human epidermal growth factor receptor 2 or estrogen receptor activation in both MCF-7 breast cancer cells and mammary epithelial cells (MECs). MECs isolated from RGS6(-/-) mice also showed a deficit in DMBA-induced ATM/p53 activation, reactive oxygen species generation and apoptosis confirming that RGS6 is required for effective activation of the DNA damage response in these cells, a critical countermeasure against carcinogen-mediated genotoxic stress. The ability of RGS6 to simultaneously enhance DNA-damage-induced apoptotic signaling and suppress oncogenic cell growth likely underlie the accelerated tumorigenesis and cellular transformation observed in DMBA-treated RGS6(-/-) mice and isolated MECs, respectively. Unsurprisingly, spontaneous tumor formation was also seen in old female RGS6(-/-) but not in wild-type mice. Our finding that RGS6 is downregulated in all human breast cancer subtypes independent of their molecular classification indicates that obtaining a means to restore the growth suppressive and pro-apoptotic actions of RGS6 in breast might be a viable means to treat a large spectrum of breast tumors.

  17. cGMP and NHR Signaling Co-regulate Expression of Insulin-Like Peptides and Developmental Activation of Infective Larvae in Strongyloides stercoralis

    PubMed Central

    Stoltzfus, Jonathan D.; Bart, Stephen M.; Lok, James B.

    2014-01-01

    The infectious form of the parasitic nematode Strongyloides stercoralis is a developmentally arrested third-stage larva (L3i), which is morphologically similar to the developmentally arrested dauer larva in the free-living nematode Caenorhabditis elegans. We hypothesize that the molecular pathways regulating C. elegans dauer development also control L3i arrest and activation in S. stercoralis. This study aimed to determine the factors that regulate L3i activation, with a focus on G protein-coupled receptor-mediated regulation of cyclic guanosine monophosphate (cGMP) pathway signaling, including its modulation of the insulin/IGF-1-like signaling (IIS) pathway. We found that application of the membrane-permeable cGMP analog 8-bromo-cGMP potently activated development of S. stercoralis L3i, as measured by resumption of feeding, with 85.1±2.2% of L3i feeding in 200 µM 8-bromo-cGMP in comparison to 0.6±0.3% in the buffer diluent. Utilizing RNAseq, we examined L3i stimulated with DMEM, 8-bromo-cGMP, or the DAF-12 nuclear hormone receptor (NHR) ligand Δ7-dafachronic acid (DA)—a signaling pathway downstream of IIS in C. elegans. L3i stimulated with 8-bromo-cGMP up-regulated transcripts of the putative agonistic insulin-like peptide (ILP) -encoding genes Ss-ilp-1 (20-fold) and Ss-ilp-6 (11-fold) in comparison to controls without stimulation. Surprisingly, we found that Δ7-DA similarly modulated transcript levels of ILP-encoding genes. Using the phosphatidylinositol-4,5-bisphosphate 3-kinase inhibitor LY294002, we demonstrated that 400 nM Δ7-DA-mediated activation (93.3±1.1% L3i feeding) can be blocked using this IIS inhibitor at 100 µM (7.6±1.6% L3i feeding). To determine the tissues where promoters of ILP-encoding genes are active, we expressed promoter::egfp reporter constructs in transgenic S. stercoralis post-free-living larvae. Ss-ilp-1 and Ss-ilp-6 promoters are active in the hypodermis and neurons and the Ss-ilp-7 promoter is active in the intestine and a

  18. Hormonal regulation and developmental role of Krüppel homolog 1, a repressor of metamorphosis, in the silkworm Bombyx mori.

    PubMed

    Kayukawa, Takumi; Murata, Mika; Kobayashi, Isao; Muramatsu, Daisuke; Okada, Chieko; Uchino, Keiro; Sezutsu, Hideki; Kiuchi, Makoto; Tamura, Toshiki; Hiruma, Kiyoshi; Ishikawa, Yukio; Shinoda, Tetsuro

    2014-04-01

    Juvenile hormone (JH) has an ability to repress the precocious metamorphosis of insects during their larval development. Krüppel homolog 1 (Kr-h1) is an early JH-inducible gene that mediates this action of JH; however, the fine hormonal regulation of Kr-h1 and the molecular mechanism underlying its antimetamorphic effect are little understood. In this study, we attempted to elucidate the hormonal regulation and developmental role of Kr-h1. We found that the expression of Kr-h1 in the epidermis of penultimate-instar larvae of the silkworm Bombyx mori was induced by JH secreted by the corpora allata (CA), whereas the CA were not involved in the transient induction of Kr-h1 at the prepupal stage. Tissue culture experiments suggested that the transient peak of Kr-h1 at the prepupal stage is likely to be induced cooperatively by JH derived from gland(s) other than the CA and the prepupal surge of ecdysteroid, although involvement of unknown factor(s) could not be ruled out. To elucidate the developmental role of Kr-h1, we generated transgenic silkworms overexpressing Kr-h1. The transgenic silkworms grew normally until the spinning stage, but their development was arrested at the prepupal stage. The transgenic silkworms from which the CA were removed in the penultimate instar did not undergo precocious pupation or larval-larval molt but fell into prepupal arrest. This result demonstrated that Kr-h1 is indeed involved in the repression of metamorphosis but that Kr-h1 alone is incapable of implementing normal larval molt. Moreover, the expression profiles and hormonal responses of early ecdysone-inducible genes (E74, E75, and Broad) in transgenic silkworms suggested that Kr-h1 is not involved in the JH-dependent modulation of these genes, which is associated with the control of metamorphosis.

  19. One of the Two Genes Encoding Nucleoid-Associated HU Proteins in Streptomyces coelicolor Is Developmentally Regulated and Specifically Involved in Spore Maturation▿ †

    PubMed Central

    Salerno, Paola; Larsson, Jessica; Bucca, Giselda; Laing, Emma; Smith, Colin P.; Flärdh, Klas

    2009-01-01

    Streptomyces genomes encode two homologs of the nucleoid-associated HU proteins. One of them, here designated HupA, is of a conventional type similar to E. coli HUα and HUβ, while the other, HupS, is a two-domain protein. In addition to the N-terminal part that is similar to that of HU proteins, it has a C-terminal domain that is similar to the alanine- and lysine-rich C termini of eukaryotic linker histones. Such two-domain HU proteins are found only among Actinobacteria. In this phylum some organisms have only a single HU protein of the type with a C-terminal histone H1-like domain (e.g., Hlp in Mycobacterium smegmatis), while others have only a single conventional HU. Yet others, including the streptomycetes, produce both types of HU proteins. We show here that the two HU genes in Streptomyces coelicolor are differentially regulated and that hupS is specifically expressed during sporulation, while hupA is expressed in vegetative hyphae. The developmental upregulation of hupS occurred in sporogenic aerial hyphal compartments and was dependent on the developmental regulators whiA, whiG, and whiI. HupS was found to be nucleoid associated in spores, and a hupS deletion mutant had an average nucleoid size in spores larger than that in the parent strain. The mutant spores were also defective in heat resistance and spore pigmentation, although they possessed apparently normal spore walls and displayed no increased sensitivity to detergents. Overall, the results show that HupS is specifically involved in sporulation and may affect nucleoid architecture and protection in spores of S. coelicolor. PMID:19717607

  20. A conserved C-terminal domain of the Aspergillus fumigatus developmental regulator MedA is required for nuclear localization, adhesion and virulence.

    PubMed

    Al Abdallah, Qusai; Choe, Se-In; Campoli, Paolo; Baptista, Stefanie; Gravelat, Fabrice N; Lee, Mark J; Sheppard, Donald C

    2012-01-01

    MedA is a developmental regulator that is conserved in the genome of most filamentous fungi. In the pathogenic fungus Aspergillus fumigatus MedA regulates conidiogenesis, adherence to host cells, and pathogenicity. The mechanism by which MedA governs these phenotypes remains unknown. Although the nuclear import of MedA orthologues has been reported in other fungi, no nuclear localization signal, DNA-binding domain or other conserved motifs have been identified within MedA. In this work, we performed a deletion analysis of MedA and identified a novel domain within the C-terminal region of the protein, designated MedA(346-557), that is necessary and sufficient for nuclear localization of MedA. We further demonstrate that MedA nuclear localization is required for the function of MedA. Surprisingly, expression of the minimal nuclear localization fragment MedA(346-557) alone was sufficient to restore conidogenesis, biofilm formation and virulence to the medA mutant strain. Collectively these results suggest that MedA functions in the regulation of transcription, and that the MedA(346-557) domain is both necessary and sufficient to mediate MedA function.

  1. The Tomato Hoffman's Anthocyaninless Gene Encodes a bHLH Transcription Factor Involved in Anthocyanin Biosynthesis That Is Developmentally Regulated and Induced by Low Temperatures.

    PubMed

    Qiu, Zhengkun; Wang, Xiaoxuan; Gao, Jianchang; Guo, Yanmei; Huang, Zejun; Du, Yongchen

    2016-01-01

    Anthocyanin pigments play many roles in plants, including providing protection against biotic and abiotic stresses. Many of the genes that mediate anthocyanin accumulation have been identified through studies of flowers and fruits; however, the mechanisms of genes involved in anthocyanin regulation in seedlings under low-temperature stimulus are less well understood. Genetic characterization of a tomato inbred line, FMTT271, which showed no anthocyanin pigmentation, revealed a mutation in a bHLH transcription factor (TF) gene, which corresponds to the ah (Hoffman's anthocyaninless) locus, and so the gene in FMTT271 at that locus was named ah. Overexpression of the wild type allele of AH in FMTT271 resulted in greater anthocyanin accumulation and increased expression of several genes in the anthocyanin biosynthetic pathway. The expression of AH and anthocyanin accumulation in seedlings was shown to be developmentally regulated and induced by low-temperature stress. Additionally, transcriptome analyses of hypocotyls and leaves from the near-isogenic lines seedlings revealed that AH not only influences the expression of anthocyanin biosynthetic genes, but also genes associated with responses to abiotic stress. Furthermore, the ah mutation was shown to cause accumulation of reactive oxidative species and the constitutive activation of defense responses under cold conditions. These results suggest that AH regulates anthocyanin biosynthesis, thereby playing a protective role, and that this function is particularly important in young seedlings that are particularly vulnerable to abiotic stresses.

  2. A Conserved C-Terminal Domain of the Aspergillus fumigatus Developmental Regulator MedA Is Required for Nuclear Localization, Adhesion and Virulence

    PubMed Central

    Al Abdallah, Qusai; Choe, Se-In; Campoli, Paolo; Baptista, Stefanie; Gravelat, Fabrice N.; Lee, Mark J.; Sheppard, Donald C.

    2012-01-01

    MedA is a developmental regulator that is conserved in the genome of most filamentous fungi. In the pathogenic fungus Aspergillus fumigatus MedA regulates conidiogenesis, adherence to host cells, and pathogenicity. The mechanism by which MedA governs these phenotypes remains unknown. Although the nuclear import of MedA orthologues has been reported in other fungi, no nuclear localization signal, DNA-binding domain or other conserved motifs have been identified within MedA. In this work, we performed a deletion analysis of MedA and identified a novel domain within the C-terminal region of the protein, designated MedA346–557, that is necessary and sufficient for nuclear localization of MedA. We further demonstrate that MedA nuclear localization is required for the function of MedA. Surprisingly, expression of the minimal nuclear localization fragment MedA346–557 alone was sufficient to restore conidogenesis, biofilm formation and virulence to the medA mutant strain. Collectively these results suggest that MedA functions in the regulation of transcription, and that the MedA346–557 domain is both necessary and sufficient to mediate MedA function. PMID:23185496

  3. Molecular cloning and characterization of the matricellular protein Sparc/osteonectin in flatfish, Scophthalmus maximus, and its developmental stage-dependent transcriptional regulation during metamorphosis.

    PubMed

    Torres-Núñez, E; Suarez-Bregua, P; Cal, L; Cal, R; Cerdá-Reverter, J M; Rotllant, J

    2015-09-01

    SPARC/osteonectin is a multifunctional matricellular glycoprotein, which is expressed in embryonic and adult tissues that undergo active proliferation and dynamic morphogenesis. Recent studies indicate that Sparc expression appears early in development, although its function and regulation during development are largely unknown. In this report, we describe the isolation, characterization, post-embryonic developmental expression and environmental thermal regulation of sparc in turbot. The full-length turbot sparc cDNA contains 930 bp and encodes a protein of 310 amino acids, which shares 77, 75 and 80% identity with human, frog and zebrafish, respectively. Results of whole-mount in situ hybridization reveal a dynamic expression profile during post-embryonic turbot development. Sparc is expressed differentially in the cranioencephalic region; mainly in jaws, branchial arches, fin folds and rays of caudal, dorsal and anal fins. Furthermore, ontogenetic studies demonstrated that Sparc gene expression is dynamically regulated during post-embryonic turbot development, with high expression during stage-specific post-embryonic remodeling. Additionally, the effect of thermal environmental conditions on turbot development and on ontogenetic sparc expression was evaluated.

  4. A myelin proteolipid protein-LacZ fusion protein is developmentally regulated and targeted to the myelin membrane in transgenic mice

    PubMed Central

    1993-01-01

    Transgenic mice were generated with a fusion gene carrying a portion of the murine myelin proteolipid protein (PLP) gene, including the first intron, fused to the E. coli LacZ gene. Three transgenic lines were derived and all lines expressed the transgene in central nervous system white matter as measured by a histochemical assay for the detection of beta-galactosidase activity. PLP-LacZ transgene expression was regulated in both a spatial and temporal manner, consistent with endogenous PLP expression. Moreover, the transgene was expressed specifically in oligodendrocytes from primary mixed glial cultures prepared from transgenic mouse brains and appeared to be developmentally regulated in vitro as well. Transgene expression occurred in embryos, presumably in pre- or nonmyelinating cells, rather extensively throughout the peripheral nervous system and within very discrete regions of the central nervous system. Surprisingly, beta- galactosidase activity was localized predominantly in the myelin in these transgenic animals, suggesting that the NH2-terminal 13 amino acids of PLP, which were present in the PLP-LacZ gene product, were sufficient to target the protein to the myelin membrane. Thus, the first half of the PLP gene contains sequences sufficient to direct both spatial and temporal gene regulation and to encode amino acids important in targeting the protein to the myelin membrane. PMID:8408224

  5. Post-developmental microRNA expression is required for normal physiology, and regulates aging in parallel to insulin/IGF-1 signaling in C. elegans.

    PubMed

    Lehrbach, Nicolas J; Castro, Cecilia; Murfitt, Kenneth J; Abreu-Goodger, Cei; Griffin, Julian L; Miska, Eric A

    2012-12-01

    Regulation of gene expression by microRNAs (miRNAs) is essential for normal development, but the roles of miRNAs in the physiology of adult animals are poorly understood. We have isolated a conditional allele of DGCR8/pash-1, which allows reversible and rapid inactivation of miRNA synthesis in vivo in Caenorhabditis elegans. This is a powerful new tool that allows dissection of post-developmental miRNA functions. We demonstrate that continuous synthesis of miRNAs is dispensable for cellular viability but critical for the physiology of adult animals. Loss of miRNA synthesis in the adult reduces lifespan and results in rapid aging. The insulin/IGF-1 signaling pathway is a critical determinant of lifespan, and is modulated by miRNAs. We find that although miRNA expression is required for some mechanisms of lifespan extension, it is not essential for the longevity of animals lacking insulin/IGF-1 signaling. Further, misregulated insulin/IGF-1 signaling cannot account for the reduced lifespan caused by disruption of miRNA synthesis. We show that miRNAs act in parallel with insulin/IGF-1 signaling to regulate a shared set of downstream genes important for physiological processes that determine lifespan. We conclude that coordinated transcriptional and post-transcriptional regulation of gene expression promotes longevity.

  6. The Tomato Hoffman’s Anthocyaninless Gene Encodes a bHLH Transcription Factor Involved in Anthocyanin Biosynthesis That Is Developmentally Regulated and Induced by Low Temperatures

    PubMed Central

    Gao, Jianchang; Guo, Yanmei; Huang, Zejun; Du, Yongchen

    2016-01-01

    Anthocyanin pigments play many roles in plants, including providing protection against biotic and abiotic stresses. Many of the genes that mediate anthocyanin accumulation have been identified through studies of flowers and fruits; however, the mechanisms of genes involved in anthocyanin regulation in seedlings under low-temperature stimulus are less well understood. Genetic characterization of a tomato inbred line, FMTT271, which showed no anthocyanin pigmentation, revealed a mutation in a bHLH transcription factor (TF) gene, which corresponds to the ah (Hoffman's anthocyaninless) locus, and so the gene in FMTT271 at that locus was named ah. Overexpression of the wild type allele of AH in FMTT271 resulted in greater anthocyanin accumulation and increased expression of several genes in the anthocyanin biosynthetic pathway. The expression of AH and anthocyanin accumulation in seedlings was shown to be developmentally regulated and induced by low-temperature stress. Additionally, transcriptome analyses of hypocotyls and leaves from the near-isogenic lines seedlings revealed that AH not only influences the expression of anthocyanin biosynthetic genes, but also genes associated with responses to abiotic stress. Furthermore, the ah mutation was shown to cause accumulation of reactive oxidative species and the constitutive activation of defense responses under cold conditions. These results suggest that AH regulates anthocyanin biosynthesis, thereby playing a protective role, and that this function is particularly important in young seedlings that are particularly vulnerable to abiotic stresses. PMID:26943362

  7. Overexpression of HOX genes is prevalent in Ewing sarcoma and is associated with altered epigenetic regulation of developmental transcription programs.

    PubMed

    Svoboda, Laurie K; Harris, Ashley; Bailey, Natashay J; Schwentner, Raphaela; Tomazou, Eleni; von Levetzow, Cornelia; Magnuson, Brian; Ljungman, Mats; Kovar, Heinrich; Lawlor, Elizabeth R

    2014-12-01

    The polycomb proteins BMI-1 and EZH2 are highly overexpressed by Ewing sarcoma (ES), a tumor of stem cell origin that is driven by EWS-ETS fusion oncogenes, most commonly EWS-FLI1. In the current study we analyzed expression of transcription programs that are controlled by polycomb proteins during embryonic development to determine if they are abnormal in ES. Our results show that polycomb target gene expression in ES deviates from normal tissues and stem cells and that, as expected, most targets are relatively repressed. However, we also discovered a paradoxical up regulation of numerous polycomb targets and these were highly enriched for homeobox (HOX) genes. Comparison of HOX profiles between malignant and non-malignant tissues revealed a distinctive HOX profile in ES, which was characterized by overexpression of posterior HOXD genes. In addition, ectopic expression of EWS-FLI1 during stem cell differentiation led to aberrant up regulation of posterior HOXD genes. Mechanistically, this up regulation was associated with altered epigenetic regulation. Specifically, ES and EWS-FLI1+ stem cells displayed a relative loss of polycomb-dependent H3K27me3 and gain of trithorax-dependent H3K4me3 at the promoters of posterior HOXD genes and also at the HOXD11.12 polycomb response element. In addition, a striking correlation was evident between HOXD13 and other genes whose regulation is coordinately regulated during embryonic development by distal enhancer elements. Together, these studies demonstrate that epigenetic regulation of polycomb target genes, in particular HOXD genes, is altered in ES and that these changes are mediated downstream of EWS-FLI1.

  8. BDNF regulates spontaneous correlated activity at early developmental stages by increasing synaptogenesis and expression of the K+/Cl- co-transporter KCC2.

    PubMed

    Aguado, Fernando; Carmona, Maria A; Pozas, Esther; Aguiló, Agustín; Martínez-Guijarro, Francisco J; Alcantara, Soledad; Borrell, Victor; Yuste, Rafael; Ibañez, Carlos F; Soriano, Eduardo

    2003-04-01

    Spontaneous neural activity is a basic property of the developing brain, which regulates key developmental processes, including migration, neural differentiation and formation and refinement of connections. The mechanisms regulating spontaneous activity are not known. By using transgenic embryos that overexpress BDNF under the control of the nestin promoter, we show here that BDNF controls the emergence and robustness of spontaneous activity in embryonic hippocampal slices. Further, BDNF dramatically increases spontaneous co-active network activity, which is believed to synchronize gene expression and synaptogenesis in vast numbers of neurons. In fact, BDNF raises the spontaneous activity of E18 hippocampal neurons to levels that are typical of postnatal slices. We also show that BDNF overexpression increases the number of synapses at much earlier stages (E18) than those reported previously. Most of these synapses were GABAergic, and GABAergic interneurons showed hypertrophy and a 3-fold increase in GAD expression. Interestingly, whereas BDNF does not alter the expression of GABA and glutamate ionotropic receptors, it does raise the expression of the recently cloned K(+)/Cl(-) KCC2 co-transporter, which is responsible for the conversion of GABA responses from depolarizing to inhibitory, through the control of the Cl(-) potential. Together, results indicate that both the presynaptic and postsynaptic machineries of GABAergic circuits may be essential targets of BDNF actions to control spontaneous activity. The data indicate that BDNF is a potent regulator of spontaneous activity and co-active networks, which is a new level of regulation of neurotrophins. Given that BDNF itself is regulated by neuronal activity, we suggest that BDNF acts as a homeostatic factor controlling the emergence, complexity and networking properties of spontaneous networks.

  9. Polypyrimidine tract binding protein homologs from Arabidopsis are key regulators of alternative splicing with implications in fundamental developmental processes.

    PubMed

    Rühl, Christina; Stauffer, Eva; Kahles, André; Wagner, Gabriele; Drechsel, Gabriele; Rätsch, Gunnar; Wachter, Andreas

    2012-11-01

    Alternative splicing (AS) generates transcript variants by variable exon/intron definition and massively expands transcriptome diversity. Changes in AS patterns have been found to be linked to manifold biological processes, yet fundamental aspects, such as the regulation of AS and its functional implications, largely remain to be addressed. In this work, widespread AS regulation by Arabidopsis thaliana Polypyrimidine tract binding protein homologs (PTBs) was revealed. In total, 452 AS events derived from 307 distinct genes were found to be responsive to the levels of the splicing factors PTB1 and PTB2, which predominantly triggered splicing of regulated introns, inclusion of cassette exons, and usage of upstream 5' splice sites. By contrast, no major AS regulatory function of the distantly related PTB3 was found. Dependent on their position within the mRNA, PTB-regulated events can both modify the untranslated regions and give rise to alternative protein products. We find that PTB-mediated AS events are connected to diverse biological processes, and the functional implications of selected instances were further elucidated. Specifically, PTB misexpression changes AS of PHYTOCHROME INTERACTING FACTOR6, coinciding with altered rates of abscisic acid-dependent seed germination. Furthermore, AS patterns as well as the expression of key flowering regulators were massively changed in a PTB1/2 level-dependent manner.

  10. Brain phosphorylation of MeCP2 at serine 164 is developmentally regulated and globally alters its chromatin association

    PubMed Central

    Stefanelli, Gilda; Gandaglia, Anna; Costa, Mario; Cheema, Manjinder S.; Di Marino, Daniele; Barbiero, Isabella; Kilstrup-Nielsen, Charlotte; Ausió, Juan; Landsberger, Nicoletta

    2016-01-01

    MeCP2 is a transcriptional regulator whose functional alterations are responsible for several autism spectrum and mental disorders. Post-translational modifications (PTMs), and particularly differential phosphorylation, modulate MeCP2 function in response to diverse stimuli. Understanding the detailed role of MeCP2 phosphorylation is thus instrumental to ascertain how MeCP2 integrates the environmental signals and directs its adaptive transcriptional responses. The evolutionarily conserved serine 164 (S164) was found phosphorylated in rodent brain but its functional role has remained uncharacterized. We show here that phosphorylation of S164 in brain is dynamically regulated during neuronal maturation. S164 phosphorylation highly impairs MeCP2 binding to DNA in vitro and largely affects its nucleosome binding and chromatin affinity in vivo. Strikingly, the chromatin-binding properties of the global MeCP2 appear also extensively altered during the course of brain maturation. Functional assays reveal that proper temporal regulation of S164 phosphorylation controls the ability of MeCP2 to regulate neuronal morphology. Altogether, our results support the hypothesis of a complex PTM-mediated functional regulation of MeCP2 potentially involving a still poorly characterized epigenetic code. Furthermore, they demonstrate the relevance of the Intervening Domain of MeCP2 for binding to DNA. PMID:27323888

  11. PRR11 regulates late-S to G2/M phase progression and induces premature chromatin condensation (PCC)

    SciTech Connect

    Zhang, Chundong; Zhang, Ying; Li, Yi; Zhu, Huifang; Wang, Yitao; Cai, Wei; Zhu, Jiang; Ozaki, Toshinori; Bu, Youquan

    2015-03-13

    Recently, we have demonstrated that proline-rich protein 11 (PRR11) is a novel tumor-related gene product likely implicated in the regulation of cell cycle progression as well as lung cancer development. However, its precise role in cell cycle progression remains unclear. In the present study, we have further investigated the expression pattern and functional implication of PRR11 during cell cycle in detail in human lung carcinoma-derived H1299 cells. According to our immunofluorescence study, PRR11 was expressed largely in cytoplasm, the amount of PRR11 started to increase in the late S phase, and was retained until just before mitotic telophase. Consistent with those observations, siRNA-mediated knockdown of PRR11 caused a significant cell cycle arrest in the late S phase. Intriguingly, the treatment with dNTPs further augmented PRR11 silencing-mediated S phase arrest. Moreover, knockdown of PRR11 also resulted in a remarkable retardation of G2/M progression, and PRR11-knockdown cells subsequently underwent G2 phase cell cycle arrest accompanied by obvious mitotic defects such as multipolar spindles and multiple nuclei. In addition, forced expression of PRR11 promoted the premature Chromatin condensation (PCC), and then proliferation of PRR11-expressing cells was massively attenuated and induced apoptosis. Taken together, our current observations strongly suggest that PRR11, which is strictly regulated during cell cycle progression, plays a pivotal role in the regulation of accurate cell cycle progression through the late S phase to mitosis. - Highlights: • PRR11 started to increase in the late S phase and was retained until just before mitotic telophase. • PRR11-knockdown caused a significant cell cycle arrest in the late S phase and G2 phase. • The treatment with dNTPs further augmented PRR11 silencing-mediated S phase arrest. • PRR11-knockdown led to multipolar spindles and multiple nuclei. • Forced expression of PRR11 promoted the PCC and inhibited

  12. Electrophoretic and Immunological Comparisons of Developmentally Regulated Proteins in Members of the Sclerotiniaceae and Other Sclerotial Fungi

    PubMed Central

    Novak, Lily Ann; Kohn, Linda M.

    1991-01-01

    The fungal stroma is a distinct developmental stage, a compact mass of hyphal cells enveloped by a melanized layer of rind cells which is produced from vegetative mycelium. Two types of stromata that are characteristic of members of the Sclerotiniaceae but are also produced in a wide range of other fungi, i.e., the determinate tuberlike sclerotium and the indeterminate platelike substratal stroma, were compared in these studies. Developmental proteins found in determinate sclerotial and indeterminate substratal stromata, but not in mycelia, were characterized and compared in 52 isolates of fungi, both ascomycetes (including 18 species in the Sclerotiniaceae and 5 species of Aspergillus) and the basidiomycete Sclerotium rolfsii. One-dimensional sodium dodecyl sulfate-polyacrylamide gel electrophoresis of mycelial, stromatal initial, and stromatal extracts demonstrated that all members of the Sclerotiniaceae produced proteins unique to stromatal extracts within a molecular weight range of 31,000 to 39,500 which composed 13 to 58% of the total protein in stromata. Proteins unique to the sclerotial stage were also produced in Sclerotium rolfsii and the Aspergillus species but within a generally lower-molecular-weight range of 11,000 to 30,000. The proteins were then characterized by two-dimensional electrophoresis to determine the number and isoelectric point of polypeptides composing each protein. Polyclonal antibodies were raised to the major 36-kDa sclerotial protein of Sclerotinia sclerotiorum (Ssp). Immunoblots demonstrated that all sclerotial proteins from species in the Sclerotiniaceae cross-reacted with anti-Ssp antibodies, while no cross-reaction was observed with proteins from substratal stromatal species in the Sclerotiniaceae, sclerotial species of Aspergillus, or Sclerotium rolfsii. Results of discriminant analysis of the data from competitive inhibition enzyme-linked immunosorbent assays were consistent with the results of immunoblotting. Three groupings

  13. Wildland fire as a self-regulating mechanism: the role of previous burns and weather in limiting fire progression.

    PubMed

    Parks, Sean A; Holsinger, Lisa M; Miller, Carol; Nelson, Cara R

    2015-09-01

    Theory suggests that natural fire regimes can result in landscapes that are both self-regulating and resilient to fire. For example, because fires consume fuel, they may create barriers to the spread of future fires, thereby regulating fire size. Top-down controls such as weather, however, can weaken this effect. While empirical examples demonstrating this pattern-process feedback between vegetation and fire exist, they have been geographically limited or did not consider the influence of time between fires and weather. The availability of remotely sensed data identifying fire activity over the last four decades provides an opportunity to explicitly quantify-the ability of wildland fire to limit the progression of subsequent fire. Furthermore, advances in fire progression mapping now allow an evaluation of how daily weather as a top-down control modifies this effect. In this study, we evaluated the ability of wildland fire to create barriers that limit the spread of subsequent fire along a gradient representing time between fires in four large study areas in the western United States. Using fire progression maps in conjunction with weather station data, we also evaluated the influence of daily weather. Results indicate that wildland fire does limit subsequent fire spread in all four study areas, but this effect decays over time; wildland fire no longer limits subsequent fire spread 6-18 years after fire, depending on the study area. We also found that the ability of fire to regulate, subsequent fire progression was substantially reduced under extreme conditions compared to moderate weather conditions in all four study areas. This study increases understanding of the spatial feedbacks that can lead to self-regulating landscapes as well as the effects of top-down controls, such as weather, on these feedbacks. Our results will be useful to managers who seek to restore natural fire regimes or to exploit recent burns when managing fire.

  14. Is water uptake by reptilian eggs regulated by physiological processes of embryos or a passive hydraulic response to developmental environments?

    PubMed

    Warner, Daniel A; Moody, Melissa A; Telemeco, Rory S

    2011-11-01

    Moisture availability is critical for successful embryonic development in many organisms. In most oviparous reptiles, for example, water exchange between eggs and the surrounding environment can have substantial fitness consequences, but regulation of this process is unclear. Here, we evaluate whether water uptake by eggs of the lizard Anolis sagrei is regulated by the presence of a live embryo or is a passive hydraulic response to substrate moisture conditions. Many eggs laid in our captive colony were infertile or contained embryos that died during early stages of development, yet these 'dead' eggs continued to gain mass similar to that of 'live' eggs at least during the first half of incubation. Our results suggest that water uptake by eggs is largely a passive hydraulic process during the first half of incubation, but active regulation by embryos may be necessary during latter stages. Maternal effects (e.g., deposition of salts into yolk) could influence this passive process during early incubation.

  15. Arabidopsis COLD SHOCK DOMAIN PROTEIN2 is a RNA chaperone that is regulated by cold and developmental signals

    SciTech Connect

    Sasaki, Kentaro; Kim, Myung-Hee; Imai, Ryozo

    2007-12-21

    Bacterial cold shock proteins (CSPs) are RNA chaperones that unwind RNA secondary structures. Arabidopsis COLD SHOCK DOMAIN PROTEIN2 (AtCSP2) contains a domain that is shared with bacterial CSPs. Here we showed that AtCSP2 binds to RNA and unwinds nucleic acid duplex. Heterologous expression of AtCSP2 complemented cold sensitivity of an Escherichia coli csp quadruple mutant, indicating that AtCSP2 function as a RNA chaperone in E. coli. AtCSP2 mRNA and protein levels increased during cold acclimation, but the protein accumulation was most prominent after 10 days of cold treatment. AtCSP2 promoter::GUS transgenic plants revealed that AtCSP2 is expressed only in root and shoot apical regions during vegetative growth but is expressed in reproductive organs such as pollens, ovules and embryos. These data indicated that AtCSP2 is involved in developmental processes as well as cold adaptation. Localization of AtCSP2::GFP in nucleolus and cytoplasm suggested different nuclear and cytosolic RNA targets.

  16. RNAi-mediated down-regulation of DCL1 and AGO1 induces developmental changes in resynthesized Arabidopsis allotetraploids

    PubMed Central

    Lackey, Erika; Ng, Danny W-K.; Chen, Z. Jeffrey

    2010-01-01

    Summary Both natural and newly synthesized allopolyploids display nonadditive gene expression changes through genetic and epigenetic mechanisms. The nonadditively expressed genes include many microRNA (miRNA) targets, suggesting a role for miRNAs and their targets in morphological variation in the allopolyploids and their progenitors. We produced dominant-negative transgenic allotetraploid plants in Arabidopsis using RNA interference (RNAi) that downregulates the expression of miRNA biogenesis genes, including DCL1 and AGO1. RNAi of DCL1 and AGO1 led to dominant negative phenotypes and decreased accumulation of several miRNAs and a tasiRNA tested in the transgenic resynthesized allotetraploids. The results demonstrated that miRNA biogenesis genes are effectively downregulated in the resynthesized allotetraploids containing redundant homoeologous genes that are difficult to be manipulated by conventional mutation screens. These lines will be useful for studying the effects of miRNA biogenesis genes on growth and developmental variation in the allopolyploids. PMID:20409179

  17. Emotional Self-Regulation, Peer Rejection, and Antisocial Behavior: Developmental Associations from Early Childhood to Early Adolescence

    PubMed Central

    Trentacosta, Christopher J.; Shaw, Daniel S.

    2009-01-01

    This study examined relations among emotional self-regulation, peer rejection, and antisocial behavior in a sample of 122 boys from low-income families who participated in a summer camp and were followed longitudinally from early childhood to early adolescence. Emotional self- regulation strategies were coded in early childhood from a waiting task, measures of peer rejection were collected during middle childhood at the summer camp, and reports of antisocial behavior were obtained during early adolescence. Structural equation modeling was utilized to examine longitudinal relations among these constructs, with results supporting a negative association between use of active distraction and peer rejection and a positive association between peer rejection and antisocial behavior. Furthermore, an indirect effect of active distraction on antisocial behavior was found through peer rejection. Thus, adaptive self-regulation strategy use in early childhood demonstrated direct longitudinal relations with peer rejection and an indirect association with antisocial behavior in early adolescence. Results have implications for early prevention and intervention efforts to foster adaptive self-regulation of emotion and reduce risk for later social problems and delinquency. PMID:20161105

  18. The Effects of Self-Regulated Learning on Community College Students' Metacognition and Achievement in Developmental Math Courses

    ERIC Educational Resources Information Center

    Campbell, Karen D. Y.

    2013-01-01

    The effects of training in self-regulation on metacognition and math achievement were investigated in this study. The moderator effect of gender, age and ethnicity on the relationships between training and the outcomes of metacognition and math achievement were also explored. The participants for this study were 116 community college students…

  19. Developmental regulation of mitochondrial biogenesis and function in the mouse mammary gland during a prolonged lactation cycle

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The regulation of mitochondrial biogenesis and function in the lactating mammary cell is poorly understood. The goal of this study was to use proteomics to