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1

Constitutive and barbital-induced expression of the Cyp6a2 allele of a high producer strain of CYP6A2 in the genetic background of a low producer strain.  

PubMed

The levels of one or more cytochrome P450 (CYP) enzymes and the respective mRNAs are found to be higher in insecticide-resistant insects than in susceptible insects. To understand better how insects regulate the levels of CYPs, we examined the expression of the Cyp6a2 gene in various strains of Drosophila melanogaster. We also took a transgenic approach to understand the molecular mechanisms that are involved in strain variation of Cyp6a2 expression. RNA blot analysis showed that the constitutive expression of Cyp6a2 varies from strain to strain; the level of CYP6A2 mRNA is barely detectable in the underproducer ry506 strain, whereas it is very high in the overproducer 91-R and MHIII-D23 strains. The long terminal repeat (LTR) of mobile element 17.6 that is found in the 3' untranslated region (UTR) of the Cyp6a2 gene of some strains does not appear to have any role on the steady-state CYP6A2 mRNA level. We also found that the Cyp6a2 gene is inducible by barbital in 91-R, ry506 as well as 91-C, which carries an LTR insertion. To examine the genetic background of the underproducer ry506 strain with respect to Cyp6a2 expression, we transformed the ry506 strain with the Cyp6a2 allele of the overproducer 91-R strain (Cyp6a2-91 R) and measured the constitutive and barbital-induced expression of the Cyp6a2-91 R transgene in the transformed flies. The Cyp6a2-91 R transgene carrying 129 bp of DNA upstream of the ATG codon did not show any constitutive or barbital-induced expression in the ry506 host genome. However, transgenes with 1331 and 985 bp upstream DNA showed similar levels of constitutive expression that were higher than that of the endogenous Cyp6a2 gene of the ry506 host strain, but lower than the expression of the same gene in the 91-R strain. Both these transgenes, with 1331 and 985 bp upstream DNA, also showed induction with 0.1 M barbital. DNA sequence analysis revealed that in both 91-R and ry506, the upstream DNA between +1 and -985 bp contains a distal and a proximal group of three potential barbie boxes, i.e. cis-elements that are thought to be involved in barbiturate-mediated induction of CYP genes. Except for four bases located near the distal cluster of barbie boxes and two other bases, the base sequence of the upstream DNA is identical in ry506 and 91-R strains. These results suggest that the underproducer ry506 strain has the trans-regulatory factors to support constitutive and induced expression of the Cyp6a2-91 R allele carrying DNA between -129 and -1331 bp regions. Possible reasons for low constitutive expression of the endogenous Cyp6a2 gene and moderate level of expression of the Cyp6a2-91 R allele in the ry506 genetic background are discussed. PMID:9852951

Dombrowski, S M; Krishnan, R; Witte, M; Maitra, S; Diesing, C; Waters, L C; Ganguly, R

1998-10-01

2

Freedom of Expression in the Original Constitution: A Bicentennial Review.  

ERIC Educational Resources Information Center

The original United States Constitution of 1787, specifically in the communication related provisions of Article 1, deals extensively with communication issues, and provides an illustration of the tensions that existed between freedom and suppression. Philosophically, there was support for freedom of expression while in real world events there was…

Kane, Peter E.

3

Sources of stochasticity in constitutive and autoregulated gene expression  

NASA Astrophysics Data System (ADS)

Gene expression is inherently noisy as many steps in the read-out of the genetic information are stochastic. To disentangle the effect of different sources of stochasticity in such systems, we consider various models that describe some processes as stochastic and others as deterministic. We review earlier results for unregulated (constitutive) gene expression and present new results for a gene controlled by negative autoregulation with cell growth modeled by linear volume growth.

Marathe, Rahul; Gomez, David; Klumpp, Stefan

2012-11-01

4

Constitutive and regulated expression vectors to construct polyphosphate deficient bacteria  

PubMed Central

Background Inorganic polyphosphate (polyP), a polymer of tens or hundreds of phosphate residues linked by ATP-like bonds, is found in all organisms and performs a wide variety of functions. PolyP is synthesized in bacterial cells by the actions of polyphosphate kinases (PPK1 and PPK2) and degraded by an exopolyphosphatase (PPX). Bacterial cells with polyP deficiencies are impaired in many structural and important cellular functions such as motility, quorum sensing, biofilm formation and virulence. Knockout mutants of the ppk1 gene have been the most frequent strategy employed to generate polyP deficient cells. Results As an alternative method to construct polyP-deficient bacteria we developed constitutive and regulated broad-host-range vectors for depleting the cellular polyP content. This was achieved by the overexpression of yeast exopolyphosphatase (PPX1). Using this approach in a polyphosphate accumulating bacteria (Pseudomonas sp. B4), we were able to eliminate most of the cellular polyP (>95%). Furthermore, the effect of overexpression of PPX1 resembled the functional defects found in motility and biofilm formation in a ppk1 mutant from Pseudomonas aeruginosa PAO1. The plasmids constructed were also successfully replicated in other bacteria such as Escherichia coli, Burkholderia and Salmonella. Conclusion To deplete polyP contents in bacteria broad-host-range expression vectors can be used as an alternative and more efficient method compared with the deletion of ppk genes. It is of great importance to understand why polyP deficiency affects vital cellular processes in bacteria. The construction reported in this work will be of great relevance to study the role of polyP in microorganisms with non-sequenced genomes or those in which orthologs to ppk genes have not been identified.

Chavez, Francisco P; Mauriaca, Cecilia; Jerez, Carlos A

2009-01-01

5

Genetic Requirements for High Constitutive SOS Expression in recA730 Mutants of Escherichia coli ?  

PubMed Central

The RecA protein in its functional state is in complex with single-stranded DNA, i.e., in the form of a RecA filament. In SOS induction, the RecA filament functions as a coprotease, enabling the autodigestion of the LexA repressor. The RecA filament can be formed by different mechanisms, but all of them require three enzymatic activities essential for the processing of DNA double-stranded ends. These are helicase, 5?–3? exonuclease, and RecA loading onto single-stranded DNA (ssDNA). In some mutants, the SOS response can be expressed constitutively during the process of normal DNA metabolism. The RecA730 mutant protein is able to form the RecA filament without the help of RecBCD and RecFOR mediators since it better competes with the single-strand binding (SSB) protein for ssDNA. As a consequence, the recA730 mutants show high constitutive SOS expression. In the study described in this paper, we studied the genetic requirements for constitutive SOS expression in recA730 mutants. Using a ?-galactosidase assay, we showed that the constitutive SOS response in recA730 mutants exhibits different requirements in different backgrounds. In a wild-type background, the constitutive SOS response is partially dependent on RecBCD function. In a recB1080 background (the recB1080 mutation retains only helicase), constitutive SOS expression is partially dependent on RecBCD helicase function and is strongly dependent on RecJ nuclease. Finally, in a recB-null background, the constitutive SOS expression of the recA730 mutant is dependent on the RecJ nuclease. Our results emphasize the importance of the 5?–3? exonuclease for high constitutive SOS expression in recA730 mutants and show that RecBCD function can further enhance the excellent intrinsic abilities of the RecA730 protein in vivo.

Vlasic, Ignacija; Simatovic, Ana; Brcic-Kostic, Krunoslav

2011-01-01

6

Constitutive nitrate reductase expression and inhibition in winged bean  

SciTech Connect

It was found that NO{sub 3}{sup {minus}} had no effect on winged bean nitrate reductase activity (NRA). Similar NRA was expressed in plants grown on NO{sub 3}{sup {minus}}, urea, NH{sub 4}{sup +}, and nil N. This indicated that the primary NR expressed in winged bean was constitutive, rather than substrate-inducible. Maximum NRA in winged bean was obtained in the light. KClO{sub 3} was capable of inhibiting NRA of leaves if added to the root growth medium or to the NR assay medium, indicating possible competition with NO{sub 3}{sup {minus}} at the reduction site. While it has previously been shown that either cycloheximide alone, or both cycloheximide and chloramphenicol impair the synthesis of NR protein, our data unexpectedly demonstrated that cycloheximide had little effect on NRA, whereas chloramphenicol greatly inhibited the expression of NRA in winged bean. One interpretation is that chloroplasts may influence the activity and/or synthesis of constitutive NR proteins.

Wu, Shenchuan; Harper, J.E. (Univ. of Illinois, Urbana (USA))

1990-05-01

7

Achieving efficient protein expression in Trichoderma reesei by using strong constitutive promoters  

PubMed Central

Backgrounds The fungus Trichoderma reesei is an important workhorse for expression of homologous or heterologous genes, and the inducible cbh1 promoter is generally used. However, constitutive expression is more preferable in some cases than inducible expression that leads to production of unwanted cellulase components. In this work, constitutive promoters of T. reesei were screened and successfully used for high level homologous expression of xylanase II. Results The transcriptional profiles of 13 key genes that participate in glucose metabolism in T. reesei were analyzed by quantitative real-time reverse-transcription polymerase chain reaction (RT-qPCR). The results indicated that the mRNA levels of pdc (encoding pyruvate decarboxylase) and eno (encoding enolase) genes were much higher than other genes under high glucose conditions. Recombinant T. reesei strains that homologously expressed xylanase II were constructed by using the promoters of the pdc and eno genes, and they respectively produced 9266?IU/ml and 8866?IU/ml of xylanase activities in the cultivation supernatant in a medium with high glucose concentration. The productivities of xylanase II were 1.61?g/L (with the pdc promoter) and 1.52?g/L (with the eno promoter), approximately accounted for 83% and 82% of the total protein secreted by T. reesei, respectively. Conclusions This work demonstrates the screening of constitutive promoters by using RT-qPCR in T. reesei, and has obtained the highest expression of recombinant xylanase II to date by using these promoters.

2012-01-01

8

Whole genome expression and biochemical correlates of extreme constitutional types defined in Ayurveda  

PubMed Central

Background Ayurveda is an ancient system of personalized medicine documented and practiced in India since 1500 B.C. According to this system an individual's basic constitution to a large extent determines predisposition and prognosis to diseases as well as therapy and life-style regime. Ayurveda describes seven broad constitution types (Prakritis) each with a varying degree of predisposition to different diseases. Amongst these, three most contrasting types, Vata, Pitta, Kapha, are the most vulnerable to diseases. In the realm of modern predictive medicine, efforts are being directed towards capturing disease phenotypes with greater precision for successful identification of markers for prospective disease conditions. In this study, we explore whether the different constitution types as described in Ayurveda has molecular correlates. Methods Normal individuals of the three most contrasting constitutional types were identified following phenotyping criteria described in Ayurveda in Indian population of Indo-European origin. The peripheral blood samples of these individuals were analysed for genome wide expression levels, biochemical and hematological parameters. Gene Ontology (GO) and pathway based analysis was carried out on differentially expressed genes to explore if there were significant enrichments of functional categories among Prakriti types. Results Individuals from the three most contrasting constitutional types exhibit striking differences with respect to biochemical and hematological parameters and at genome wide expression levels. Biochemical profiles like liver function tests, lipid profiles, and hematological parameters like haemoglobin exhibited differences between Prakriti types. Functional categories of genes showing differential expression among Prakriti types were significantly enriched in core biological processes like transport, regulation of cyclin dependent protein kinase activity, immune response and regulation of blood coagulation. A significant enrichment of housekeeping, disease related and hub genes were observed in these extreme constitution types. Conclusion Ayurveda based method of phenotypic classification of extreme constitutional types allows us to uncover genes that may contribute to system level differences in normal individuals which could lead to differential disease predisposition. This is a first attempt towards unraveling the clinical phenotyping principle of a traditional system of medicine in terms of modern biology. An integration of Ayurveda with genomics holds potential and promise for future predictive medicine.

Prasher, Bhavana; Negi, Sapna; Aggarwal, Shilpi; Mandal, Amit K; Sethi, Tav P; Deshmukh, Shailaja R; Purohit, Sudha G; Sengupta, Shantanu; Khanna, Sangeeta; Mohammad, Farhan; Garg, Gaurav; Brahmachari, Samir K; Mukerji, Mitali

2008-01-01

9

Constitutive heterochromatin: a surprising variety of expressed sequences  

Microsoft Academic Search

The organization of chromosomes into euchromatin and heterochromatin is amongst the most important and enigmatic aspects of\\u000a genome evolution. Constitutive heterochromatin is a basic yet still poorly understood component of eukaryotic chromosomes,\\u000a and its molecular characterization by means of standard genomic approaches is intrinsically difficult. Although recent evidence\\u000a indicates that the presence of transcribed genes in constitutive heterochromatin is a

Patrizio Dimitri; Ruggiero Caizzi; Ennio Giordano; Maria Carmela Accardo; Giovanna Lattanzi; Giuseppe Biamonti

2009-01-01

10

Increased platelet activation and thrombosis in transgenic mice expressing constitutively active P2Y12 receptor  

PubMed Central

Summary Background In our previous in vitro study we reported a constitutively active chimeric P2Y12 receptor (cP2Y12) and found AR-C78511 is a potent inverse agonist at this receptor. The role of this cP2Y12 receptor in platelet activation and thrombosis is not clear. Objectives To investigate the physiological implications of the constitutively active P2Y12 receptor in platelet activation, thrombus formulation and evaluate the antiplatelet activity of AR-C78511 as an inverse agonist. Methods and Results We generated transgenic mice conditionally and platelet-specifically expressing cP2Y12. High expression of cP2Y12 receptor in platelets increased platelet reactivity as evidenced by increased platelet aggregation in response to multiple platelet agonists. Moreover, transgenic mice displayed shortened bleeding time, more rapid and stable thrombus formation in mesenteric artery injured with FeCl3. The constitutive activity of cP2Y12 in platelets was confirmed by decreased platelet cAMP levels and constitutive Akt phosphorylation in the absence of agonists. AR-C78511 reversed the cAMP decrease in transgenic mouse platelets, and exhibited superior antiplatelet effect over AR-C69931MX in transgenic mice. Conclusions These findings further emphasize the importance of P2Y12 in platelet activation, hemostasis and thrombosis, as well as the prothrombotic role of constitutive activity of P2Y12. Our data also validates the in vivo inverse agonist activity of AR-C78511 and confirms its superior antiplatelet activity over neutral antagonist.

Zhang, Y.; Ye, J.; Hu, L.; Zhang, S.; Zhang, S.H.; Li, Y.; Kunapuli, S.P.; Ding, Z.

2012-01-01

11

Distinct expression and ligand-binding profiles of two constitutively active GPR17 splice variants  

PubMed Central

Background and purpose: In humans and non-human primates, the 7TM receptor GPR17 exists in two isoforms differing only by the length of the N-terminus. Of these, only the short isoform has previously been characterized. Hence, we investigated gene expression and ligand-binding profiles of both splice variants and furthermore uncovered and characterized constitutive activity of both isoforms. Experimental approach: Expression levels of the hGPR17 isoforms were determined in several brain regions as well as heart and kidney using quantitative RT-PCR. A CREB reporter assay and [35S]-GTP?S binding were employed to assess the constitutive activity and the activation by UDP, UDP-glucose and -galactose and the cysteinyl leukotrienes LTC4 and LTD4. Leukotriene binding and induction of internalization were furthermore tested using homologous competition binding and antibody-feeding experiments respectively. Key results: The short isoform (hGPR17-S) was expressed more abundantly (eight- to 23-fold) in the brain than the long isoform (hGPR17-L), whereas the opposite was observed in heart and kidney. As previously reported, the uracil nucleotides activated hGPR17-S with micromolar potencies. However, much lower potencies were observed for hGPR17-L with a 50- to 170-fold increase in EC50. Furthermore, contrary to previous reports, neither of the isoforms was activated or bound by the cysteinyl leukotrienes. Finally, both receptors were demonstrated to be constitutively active through G?i. Conclusions and implications: We present the first isoform-specific characterization of GPR17 and show that differences exist between the isoforms, in both expression pattern and pharmacological profile. In turn, our results indicate that the two human isoforms might serve tissue-specific functions.

Benned-Jensen, T; Rosenkilde, MM

2010-01-01

12

Constitutive SOCS-3 expression protects T-cell lymphoma against growth inhibition by IFN?  

Microsoft Academic Search

Signal transducer and activator of transcription (Stat)3 is constitutively activated in cutaneous T-cell lymphoma (CTCL), where it protects tumour cells against apoptosis. The constitutive activation of Stat3 leads to a constitutive expression of suppressor of cytokine signalling (SOCS)-3. In healthy cells, SOCS-3 is transiently expressed following cytokine stimulation and functions as a negative feedback inhibitor of the Stat3-activating kinases. Here,

C Brender; P Lovato; V H Sommer; A Woetmann; A-M Mathiesen; C Geisler; M Wasik; N Řdum

2005-01-01

13

Upregulation of the constitutively expressed HSC70 by KLF4  

Microsoft Academic Search

Krüppel-like factor 4 (KLF4) is a transcription factor that is abundantly expressed in various organisms from bacteria to\\u000a mammals. It has been demonstrated that KLF4 regulates the expression of a wide range of genes. Analysis of KLF4 target genes\\u000a reveals its diverse regulatory functions in cell growth, proliferation, differentiation, embryogenesis, and inflammation.\\u000a However, the regulation of the expression of inducible

Ying Liu; Jie Zhao; Junwen Liu; Huali Zhang; Meidong Liu; Xianzhong Xiao

2008-01-01

14

A constitutive gene expression system derived from the tCUP cryptic promoter elements  

Microsoft Academic Search

A limited number of constitutive promoters have been used to direct transgene expression in plants and they are often derived from non-plant sources. Here, we describe novel gene-regulatory elements which are associated with a cryptic constitutive promoter from tobacco, tCUP, and modifications that were made to create a strong gene-expression system that is effective across all living cell types from

K. Malik; K. Wu; X.-Q. Li; T. Martin-Heller; M. Hu; E. Foster; L. Tian; C. Wang; K. Ward; M. Jordan; D. Brown; S. Gleddie; D. Simmonds; S. Zheng; J. Simmonds; B. Miki

2002-01-01

15

Improved Tet-responsive promoters with minimized background expression  

PubMed Central

Background The performance of the tetracycline controlled transcriptional activation system (Tet system) depends critically on the choice of minimal promoters. They are indispensable to warrant low expression levels with the system turned "off". On the other hand, they must support high level of gene expression in the "on"-state. Results In this study, we systematically modified the widely used Cytomegalovirus (CMV) minimal promoter to further minimize background expression, resulting in an improved dynamic expression range. Using both plasmid-based and retroviral gene delivery, our analysis revealed that especially background expression levels could be significantly reduced when compared to previously established "standard" promoter designs. Our results also demonstrate the possibility to fine-tune expression levels in non-clonal cell populations. They also imply differences regarding the requirements for tight regulation and high level induction between transient and stable gene transfer systems. Conclusions Until now, our understanding of mammalian transcriptional regulation including promoter architecture is limited. Nevertheless, the partly empirical modification of cis-elements as shown in this study can lead to the specific improvement of the performance of minimal promoters. The novel composite Ptet promoters introduced here will further expand the utility of the Tet system.

2010-01-01

16

A Dedicated Promoter Drives Constitutive Expression of the Cell-Autonomous Immune Resistance GTPase, Irga6 (IIGP1) in Mouse Liver  

PubMed Central

Background In general, immune effector molecules are induced by infection. Methodology and Principal Findings However, strong constitutive expression of the cell-autonomous resistance GTPase, Irga6 (IIGP1), was found in mouse liver, contrasting with previous evidence that expression of this protein is exclusively dependent on induction by IFN?. Constitutive and IFN?-inducible expression of Irga6 in the liver were shown to be dependent on transcription initiated from two independent untranslated 5? exons, which splice alternatively into the long exon encoding the full-length protein sequence. Irga6 is expressed constitutively in freshly isolated hepatocytes and is competent in these cells to accumulate on the parasitophorous vacuole membrane of infecting Toxoplasma gondii tachyzoites. Conclusions and Significance The role of constitutive hepatocyte expression of Irga6 in resistance to parasites invading from the gut via the hepatic portal system is discussed.

Zeng, Jia; Parvanova, Iana Angelova; Howard, Jonathan C.

2009-01-01

17

GFAP-expressing progenitors are the principal source of constitutive neurogenesis in adult mouse forebrain  

Microsoft Academic Search

Establishing the cellular identity in vivo of adult multipotent neural progenitors is fundamental to understanding their biology. We used two transgenic strategies to determine the relative contribution of glial fibrillary acidic protein (GFAP)-expressing progenitors to constitutive neurogenesis in the adult forebrain. Transgenically targeted ablation of dividing GFAP-expressing cells in the adult mouse subependymal and subgranular zones stopped the generation of

A Denise R Garcia; Ngan B Doan; Tetsuya Imura; Toby G Bush; Michael V Sofroniew

2004-01-01

18

Snf1-Dependent and Snf1-Independent Pathways of Constitutive ADH2 Expression in Saccharomyces cerevisiae  

PubMed Central

The transcription factor Adr1 directly activates the expression of genes encoding enzymes in numerous pathways that are upregulated after the exhaustion of glucose in the yeast Saccharomyces cerevisiae. ADH2, encoding the alcohol dehydrogenase isozyme required for ethanol oxidation, is a highly glucose-repressed, Adr1-dependent gene. Using a genetic screen we isolated >100 mutants in 12 complementation groups that exhibit ADR1-dependent constitutive ADH2 expression on glucose. Temperature-sensitive alleles are present among the new constitutive mutants, indicating that essential genes play a role in ADH2 repression. Among the genes we cloned is MOT1, encoding a repressor that inhibits TBP binding to the promoter, thus linking glucose repression with TBP access to chromatin. Two genes encoding proteins involved in vacuolar function, FAB1 and VPS35, and CDC10, encoding a nonessential septin, were also uncovered in the search, suggesting that vacuolar function and the cytoskeleton have previously unknown roles in regulating gene expression. Constitutive activation of ADH2 expression by Adr1 is SNF1-dependent in a strain with a defective MOT1 gene, whereas deletion of SNF1 did not affect constitutive ADH2 expression in the mutants affecting vacuolar or septin function. Thus, the mutant search revealed previously unknown Snf1-dependent and -independent pathways of ADH2 expression.

Voronkova, Valentina; Kacherovsky, Nataly; Tachibana, Christine; Yu, Diana; Young, Elton T.

2006-01-01

19

GASTRO-D-01631R1 Constitutive CXCL12 expression induces anoikis in colorectal carcinoma cells  

PubMed Central

Background & Aims CXCL12 and CXCR4 signaling plays critical roles in development, homeostasis, and tumor metastasis. Previously we have shown that epigenetic silencing of CXCL12 in colorectal and mammary carcinoma promotes metastasis. Anoikis is an essential process of colonic epithelial turnover and limits the metastatic progression of carcinoma. We sought to determine the role for anoikis in limiting tumor metastasis upon re-expression of CXCL12 in human colorectal carcinoma cells. Methods Tumor formation and metastasis of colonic carcinoma cells was monitored using in vivo bioluminescence imaging. Anoikis was defined using caspase-3/7, focal adhesion kinase (FAK) and p130Cas cleavage, DNA fragmentation, and cell survival assays. Phosphorylation of ERK1/2 was monitored by immunoblot and immunohistochemistry and activity inhibited using U0126. Results Constitutive expression of CXCL12 in human colorectal carcinoma cells reduced orthotopic tumor formation and inhibited metastasis in SCID mice. Further, CXCL12 expression induced apoptosis specifically in non-adherent colorectal carcinoma cells. Apoptotic cell death was preceded by hypophosphorylation and cleavage of FAK and p130Cas leading to increased cellular detachment in culture and was dependent upon alterations in the extracellular matrix. Similar to in vivo colonic epithelium, CXCL12-induced anoikis of carcinoma cells was dependent upon basal ERK1/2 activation. Conclusions These data significantly expand the current paradigm of chemokine signaling in carcinogenesis by showing that endogenous CXCL12, in marked contrast to exogenous ligand, inhibits tumor metastasis through increased anoikis. Altered ERK1/2 signaling provides a mechanism for the dichotomy between the physiologic and pathophysiologic roles of CXCL12-CXCR4 signaling in the intestinal epithelium.

Wendt, Michael K.; Drury, Luke J.; Vongsa, Rebecca A.; Dwinell, Michael B.

2008-01-01

20

Constitutive Expression of the Yeast HEM1 Gene is Actually a Composite of Activation and Repression  

Microsoft Academic Search

We show that HEM1 (encoding 5-aminolevulinate synthase) expression, while constitutive under all steadystate growth conditions tested, is activated by the HAP2-HAP3 global activation system that controls expression of apocytochromes. This finding creates a paradox because apocytochrome activation by HAP2-HAP3 is highly regulated, subject to induction by heme, and subject to further derepression by a shift from glucose medium to one

Teresa Keng; Leonard Guarente

1987-01-01

21

Differential Regulation of Constitutive Major Histocompatibility Complex Class I Expression in T and B Lymphocytes  

Microsoft Academic Search

Summary Major histocompatibility complex (MHC) class I antigens are constitutively expressed yet highly induced by interferon (IFN) during inflammation. We found that not only IFN-induced but also normal basal expression of MHC I required IFN receptors and signal transducer and acti- vator of transcription (STAT)1, providing genetic evidence for continuous IFN signaling. Sur- prisingly, an IFN-independent requirement for STAT1 was

Chien-Kuo Lee; Ramon Gimeno; David E. Levy

22

Fundamental role for HIF-1? in constitutive expression of human ? defensin-1  

PubMed Central

Antimicrobial peptides are secreted by the intestinal epithelium to defend from microbial threats. The role of human ? defensin-1 (hBD-1) is notable because its gene (beta-defensin 1 (DEFB1)) is constitutively expressed and its antimicrobial activity is potentiated in the low-oxygen environment that characterizes the intestinal mucosa. Hypoxia-inducible factor (HIF) is stabilized even in healthy intestinal mucosa, and we identified that epithelial HIF-1? maintains expression of murine defensins. Extension to a human model revealed that basal HIF-1? is critical for the constitutive expression of hBD-1. Chromatin immunoprecipitation identified HIF-1? binding to a hypoxia response element in the DEFB1 promoter whose importance was confirmed by site-directed mutagenesis. We used 94 human intestinal samples to identify a strong expression correlation between DEFB1 and the canonical HIF-1? target GLUT1. These findings indicate that basal HIF-1? is critical for constitutive expression of enteric DEFB1 and support targeting epithelial HIF for restoration and maintenance of intestinal integrity.

Kelly, C J; Glover, L E; Campbell, E L; Kominsky, D J; Ehrentraut, S F; Bowers, B E; Bayless, A J; Saeedi, B J; Colgan, S P

2013-01-01

23

Fundamental role for HIF-1? in constitutive expression of human ? defensin-1.  

PubMed

Antimicrobial peptides are secreted by the intestinal epithelium to defend from microbial threats. The role of human ? defensin-1 (hBD-1) is notable because its gene (beta-defensin 1 (DEFB1)) is constitutively expressed and its antimicrobial activity is potentiated in the low-oxygen environment that characterizes the intestinal mucosa. Hypoxia-inducible factor (HIF) is stabilized even in healthy intestinal mucosa, and we identified that epithelial HIF-1? maintains expression of murine defensins. Extension to a human model revealed that basal HIF-1? is critical for the constitutive expression of hBD-1. Chromatin immunoprecipitation identified HIF-1? binding to a hypoxia response element in the DEFB1 promoter whose importance was confirmed by site-directed mutagenesis. We used 94 human intestinal samples to identify a strong expression correlation between DEFB1 and the canonical HIF-1? target GLUT1. These findings indicate that basal HIF-1? is critical for constitutive expression of enteric DEFB1 and support targeting epithelial HIF for restoration and maintenance of intestinal integrity. PMID:23462909

Kelly, C J; Glover, L E; Campbell, E L; Kominsky, D J; Ehrentraut, S F; Bowers, B E; Bayless, A J; Saeedi, B J; Colgan, S P

2013-03-06

24

Constitutive gene expression and specification of tissue identity in adult planarian biology  

PubMed Central

Planarians are flatworms that constitutively maintain adult tissues through cell turnover and can regenerate entire organisms from tiny body fragments. In addition to requiring new cells (from neoblasts), these feats require mechanisms that specify tissue identity in the adult. Critical roles for Wnt and BMP signaling in regeneration and maintenance of the body axes have been uncovered, among other regulatory factors. Available data indicate that genes involved in positional identity regulation at key embryonic stages in other animals display persisting regionalized expression in adult planarians. These expression patterns suggest that a constitutively active gene expression map exists for maintenance of the planarian body. Planarians therefore present a fertile ground for identification of factors regulating regionalization of the metazoan body plan and for study of the attributes of these factors that can lead to maintenance and regeneration of adult tissues.

Reddien, Peter W.

2011-01-01

25

Construction of non-invasively constitutive expression vectors using a metagenome-derived promoter for soluble expression of proteins.  

PubMed

Expression of soluble and functional proteins has been one of the critical challenges to many aspects of synthetic biology, metabolic and protein engineering. Among the current methods for expression of target proteins, constitutive expression systems offer several advantages over inducible systems, which require a chemical or physical inducer. In a previous study, a G196 DNA fragment containing constitutive promoters was mined from the soil metagenome and evaluated for the expression of target proteins in the functional and soluble state. In this study, we further improved this system by constructing a series of constitutive expression vectors, pCEM (using the CEM promoter trimmed from G196), pCEMT (incorporating rrnB T1 and T2 terminator into the downstream region of MCS in pCEM) and pRCEMT (grafting the cis-acting region of pCEMT into a low-copy-number plasmid). Subsequently, genes encoding GFPuv, esterase 1767 and ?-glucosidase were subcloned into the resulting vectors, and their expression level and solubility were compared with those of IPTG-inducible vector systems pQE30 and pTrc99A. The extent of homogeneity and the ratio of the soluble fraction in the pRCEMT vector were relatively higher, without any delay of growth rate, than that of the pQE30 or pTrc99A. These results indicate that new expression vectors with moderate constitutive function could more easily lead to a homogenous population of cells expressing target proteins than those with conventionally inducible promoters. PMID:23358812

Cheong, Dea-Eun; Choi, Jong Hyun; Song, Jae Jun; Kim, Geun-Joong

2013-01-29

26

Constitutive Expression of the CIRCADIAN CLOCK ASSOCIATED 1 ( CCA1) Gene Disrupts Circadian Rhythms and Suppresses Its Own Expression  

Microsoft Academic Search

The CIRCADIAN CLOCK ASSOCIATED 1 (CCA1) gene encodes a MYB-related transcription factor involved in the phytochrome induction of a light-harvesting chlorophyll a\\/b-protein (Lhcb) gene. Expression of the CCA1 gene is transiently induced by phytochrome and oscillates with a circadian rhythm. Constitutive expression of CCA1 protein in transgenic plants abolished the circadian rhythm of several genes with dramatically different phases. These

Zhi-Yong Wang; Elaine M. Tobin

1998-01-01

27

Differences in physical characteristics, perinatal histories, and social backgrounds between children with growth hormone deficiency and constitutional short stature  

Microsoft Academic Search

Four hundred and forty-nine children with heights below -2.5 SD were identified by screening for height a total population of 48221 in three Scottish cities. Children participating in the study could be classified into 5 groups: severe growth hormone deficiency (n = 13), partial growth hormone deficiency (n = 25), low birthweight short stature (n = 34), constitutional short stature

G V Vimpani; A F Vimpani; S J Pocock; J W Farquhar

1981-01-01

28

Conditional expression of a constitutively active aryl hydrocarbon receptor in MCF-7 human breast cancer cells.  

PubMed

In addition to inducing transcription of a battery of target genes encoding drug-metabolizing enzymes, the environmental pollutant 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) is known to induce antiestrogenic responses. However, the mechanisms underlying such complex biologic responses affecting growth and differentiation remain unclear. In the present study we have investigated biological effects of a constitutively active mutant of the aryl hydrocarbon (Ah) receptor (CA-AhR), in particular whether it modulates estrogen receptor function in human MCF-7 breast cancer cells. To this end, the CA-AhR protein was conditionally expressed using the tet repressor. Expression of CA-AhR resulted in constitutive formation of a DNA-binding AhR-aryl hydrocarbon receptor nuclear translocator heterodimeric complex and enhanced expression of the Ah receptor target gene CYP1A1 in the absence of TCDD. Moreover, expression of CA-AhR inhibited estrogen-dependent cathepsin D expression and growth of these cells. Thus, the present model system conditionally expressing the CA-AhR protein provides a novel tool for the investigation of AhR-mediated signaling pathways. PMID:12051661

Köhle, Christoph; Hassepass, Ingo; Bock-Hennig, Barbara S; Walter Bock, Karl; Poellinger, Lorenz; McGuire, Jacqueline

2002-06-15

29

Constitutive Expression of Human Bcl2 Modulates Nitrogen Mustard and Camptothecin Induced Apoptosis  

Microsoft Academic Search

Bcl-2 is a novel protooncogene which prolongs cell survival and sup presses apoptosis. We examined whether constitutive expression of trans- fected human bcl-2 conferred resistance to two different DNA damaging drugs, nitrogen mustard (HN2) and camptothecin (CPT) in a murine, IL-3 dependent cell line (FL5.12). HN2 treatment produced 2-fold less cell death and DNA degradation in cells overexpressing bcl-2 relative

M. I. Walton; D. Whysong; P. M. O'Connor; D. Hockenbery; S. J. Korsmeyer; K. W. Kohn

1993-01-01

30

Constitutive expression of E- and P-selectin cognate ligands in human endothelial cells.  

PubMed Central

On human endothelial cells from umbilical cord (HUVEC) are present, in addition to E- and P-selectins, their cognate ligands. Differently from selectins, the ligand expression is constitutive and not modulated by interleukin-1beta. Such ligands appear to be different from the ones present in promyelocytic cells in order to promote cell adhesion to immobilized selectins. The expression of selectin-ligands on HUVEC cells suggest that selectins can participate in endothelial signalling besides their role as adhesion molecules for circulating blood cells. However, despite their role in chemotaxis, selectins do not contribute to HUVEC tube formation in Matrigel.

Palma, C; Bellarosa, D; Nardelli, F; Mannori, G; Manzini, S

1998-01-01

31

Constitutive Type VI Secretion System Expression Gives Vibrio cholerae Intra- and Interspecific Competitive Advantages  

PubMed Central

The type VI secretion system (T6SS) mediates protein translocation across the cell membrane of Gram-negative bacteria, including Vibrio cholerae – the causative agent of cholera. All V. cholerae strains examined to date harbor gene clusters encoding a T6SS. Structural similarity and sequence homology between components of the T6SS and the T4 bacteriophage cell-puncturing device suggest that the T6SS functions as a contractile molecular syringe to inject effector molecules into prokaryotic and eukaryotic target cells. Regulation of the T6SS is critical. A subset of V. cholerae strains, including the clinical O37 serogroup strain V52, express T6SS constitutively. In contrast, pandemic strains impose tight control that can be genetically disrupted: mutations in the quorum sensing gene luxO and the newly described regulator gene tsrA lead to constitutive T6SS expression in the El Tor strain C6706. In this report, we examined environmental V. cholerae isolates from the Rio Grande with regard to T6SS regulation. Rough V. cholerae lacking O-antigen carried a nonsense mutation in the gene encoding the global T6SS regulator VasH and did not display virulent behavior towards Escherichia coli and other environmental bacteria. In contrast, smooth V. cholerae strains engaged constitutively in type VI-mediated secretion and displayed virulence towards prokaryotes (E. coli and other environmental bacteria) and a eukaryote (the social amoeba Dictyostelium discoideum). Furthermore, smooth V. cholerae strains were able to outcompete each other in a T6SS-dependent manner. The work presented here suggests that constitutive T6SS expression provides V. cholerae with an advantage in intraspecific and interspecific competition.

Miyata, Sarah T.; Bachmann, Verena; Brooks, Teresa M.; Moloney, Jessica; Sosa, Oscar; Silva, David; Duran-Gonzalez, Jorge; Provenzano, Daniele; Pukatzki, Stefan

2012-01-01

32

Constitutive type VI secretion system expression gives Vibrio cholerae intra- and interspecific competitive advantages.  

PubMed

The type VI secretion system (T6SS) mediates protein translocation across the cell membrane of Gram-negative bacteria, including Vibrio cholerae - the causative agent of cholera. All V. cholerae strains examined to date harbor gene clusters encoding a T6SS. Structural similarity and sequence homology between components of the T6SS and the T4 bacteriophage cell-puncturing device suggest that the T6SS functions as a contractile molecular syringe to inject effector molecules into prokaryotic and eukaryotic target cells. Regulation of the T6SS is critical. A subset of V. cholerae strains, including the clinical O37 serogroup strain V52, express T6SS constitutively. In contrast, pandemic strains impose tight control that can be genetically disrupted: mutations in the quorum sensing gene luxO and the newly described regulator gene tsrA lead to constitutive T6SS expression in the El Tor strain C6706. In this report, we examined environmental V. cholerae isolates from the Rio Grande with regard to T6SS regulation. Rough V. cholerae lacking O-antigen carried a nonsense mutation in the gene encoding the global T6SS regulator VasH and did not display virulent behavior towards Escherichia coli and other environmental bacteria. In contrast, smooth V. cholerae strains engaged constitutively in type VI-mediated secretion and displayed virulence towards prokaryotes (E. coli and other environmental bacteria) and a eukaryote (the social amoeba Dictyostelium discoideum). Furthermore, smooth V. cholerae strains were able to outcompete each other in a T6SS-dependent manner. The work presented here suggests that constitutive T6SS expression provides V. cholerae with an advantage in intraspecific and interspecific competition. PMID:23110230

Unterweger, Daniel; Kitaoka, Maya; Miyata, Sarah T; Bachmann, Verena; Brooks, Teresa M; Moloney, Jessica; Sosa, Oscar; Silva, David; Duran-Gonzalez, Jorge; Provenzano, Daniele; Pukatzki, Stefan

2012-10-26

33

Differential Regulation of Constitutive Major Histocompatibility Complex Class I Expression in T and B Lymphocytes  

PubMed Central

Major histocompatibility complex (MHC) class I antigens are constitutively expressed yet highly induced by interferon (IFN) during inflammation. We found that not only IFN-induced but also normal basal expression of MHC I required IFN receptors and signal transducer and activator of transcription (STAT)1, providing genetic evidence for continuous IFN signaling. Surprisingly, an IFN-independent requirement for STAT1 was also found, specifically in T lymphocytes, where MHC class I expression was not fully accounted for by IFN signaling. This IFN-independent pathway maintained tyrosine phosphorylation of STAT1 in T but not B lymphocytes even in the absence of IFN receptors. Interestingly, interleukin (IL)-7 selectively activated STAT1 and induced MHC class I in mature T but not B cells. These loss of function studies demonstrate an essential role of endogenous IFN and activated STAT1 for constitutive MHC class I expression in normal mice and define IL-7–dependent but IFN-independent regulation of STAT1 restricted to T lymphocytes.

Lee, Chien-Kuo; Gimeno, Ramon; Levy, David E.

1999-01-01

34

Constitutive expression of a trypsin protease inhibitor confers multiple stress tolerance in transgenic tobacco.  

PubMed

Protease inhibitors have been reported to confer insect resistance in transgenic plants, except for a rice protease inhibitor that conferred drought tolerance in transgenic rice plants. We have cloned a protease inhibitor of tobacco that is expressed under treatment with ABA, hydrogen peroxide, methyl jasmonate and wounding. The cDNA codes for a six-domain serine protease inhibitor with a deduced sequence of 396 amino acids. We have generated transgenic tobacco plants expressing the protease inhibitor constitutively under the 35S promoter. When analyzed in the T(2) generation, these transgenic plants exhibited tolerance to sodium chloride, variable pH and sorbitol, together with the expected resistance to the insect pests Spodoptera litura and Helicoverpa armigera. The transgenic plants showed enhanced seed germination, root length and root-shoot ratio, significantly enhanced total chlorophyll content and reduced thiobarbituric acid-reactive substances under stress. Under sodium chloride treatment, the transgenic plants have enhanced protease inhibitor activity. The transgenic plants exhibited a higher potassium content and an optimum Na+/K+ ratio. To our knowledge, this is the first report of transgenic plants with constitutive protease inhibitor expression showing tolerance to a wide range variable pH in the culture medium along with other stresses. PMID:19179349

Srinivasan, Tantravahi; Kumar, Koppolu Raja Rajesh; Kirti, Pulugurtha Bharadwaja

2009-01-28

35

ALK1 signalling analysis identifies angiogenesis related genes and reveals disparity between TGF-? and constitutively active receptor induced gene expression  

PubMed Central

Background TGF-?1 is an important angiogenic factor involved in the different aspects of angiogenesis and vessel maintenance. TGF-? signalling is mediated by the T?RII/ALK5 receptor complex activating the Smad2/Smad3 pathway. In endothelial cells TGF-? utilizes a second type I receptor, ALK1, activating the Smad1/Smad5 pathway. Consequently, a perturbance of ALK1, ALK5 or T?RII activity leads to vascular defects. Mutations in ALK1 cause the vascular disorder hereditary hemorrhagic telangiectasia (HHT). Methods The identification of ALK1 and not ALK5 regulated genes in endothelial cells, might help to better understand the development of HHT. Therefore, the human microvascular endothelial cell line HMEC-1 was infected with a recombinant constitutively active ALK1 adenovirus, and gene expression was studied by using gene arrays and quantitative real-time PCR analysis. Results After 24 hours, 34 genes were identified to be up-regulated by ALK1 signalling. Analysing ALK1 regulated gene expression after 4 hours revealed 13 genes to be up- and 2 to be down-regulated. Several of these genes, including IL-8, ET-1, ID1, HPTP? and TEAD4 are reported to be involved in angiogenesis. Evaluation of ALK1 regulated gene expression in different human endothelial cell types was not in complete agreement. Further on, disparity between constitutively active ALK1 and TGF-?1 induced gene expression in HMEC-1 cells and primary HUVECs was observed. Conclusion Gene array analysis identified 49 genes to be regulated by ALK1 signalling and at least 14 genes are reported to be involved in angiogenesis. There was substantial agreement between the gene array and quantitative real-time PCR data. The angiogenesis related genes might be potential HHT modifier genes. In addition, the results suggest endothelial cell type specific ALK1 and TGF-? signalling.

Lux, Andreas; Salway, Fiona; Dressman, Holly K; Kroner-Lux, Gabriele; Hafner, Mathias; Day, Philip JR; Marchuk, Douglas A; Garland, John

2006-01-01

36

RNAi-mediated suppression of constitutive pulmonary gene expression by small interfering RNA in mice.  

PubMed

The ability of synthetic small interfering RNA (siRNA) to silence gene expression makes it a useful tool in biomedical research. However, effective and non-toxic functional siRNA delivery to mouse lungs in vivo is still a key challenge, and regulation of constitutively expressed genes is poorly characterized. Following in vitro validation of siRNA molecules, naked, stabilized siRNA (AtuRNAi) was applied intranasally (i.n.) by droplets or intratracheally (i.t.) by MicroSprayer in female C57BL/6 mice. Distribution of Cy3-tagged siRNAs was examined. Pulmonary expression of ubiquitously (lamin B1) or cell-specific (E-cadherin, VE-cadherin), constitutive genes was analysed by TaqMan-realtime-PCR. Further, formulated lipoplex-siRNA, which has enhanced transfection efficiency, was applied i.t. or intravenously (i.v.). Single i.t. as compared to i.n. application of unformulated siRNA resulted in higher delivery efficiency and homogenous pulmonary distribution. After inhalation of target-specific siRNA, reduction of epithelial E-cadherin by 21%, but no significant reduction of endothelial VE-cadherin or ubiquitously expressed lamin B1 was observed. Pharmacokinetic analysis revealed rapid transfer of intact siRNA molecules into the vascular system and accumulation in the kidneys, calling lung specificity into question. I.t. application of lipoplex-siRNA evoked inflammation. In contrast, i.v. application of lipoplex-siRNA specifically reduced expression of VE-cadherin mRNA by about 50% in lungs without evoking lung cellular influx. In conclusion, sufficient pulmonary distribution of aerosolized siRNA was attained in mice by MicroSprayer, however development of appropriate siRNA carriers is highly desirable to improve lung-specific functional inhalative siRNA delivery. Pulmonary knockdown of constitutive endothelial targets by 50% was achieved by i.v. application of lipoplex-siRNA. PMID:20362688

Gutbier, Birgitt; Kube, Stefanie M; Reppe, Katrin; Santel, Ansgar; Lange, Christian; Kaufmann, Jörg; Suttorp, Norbert; Witzenrath, Martin

2010-04-01

37

Drosophila CLOCK Is Constitutively Expressed in Circadian Oscillator and Nonoscillator Cells  

PubMed Central

CLOCK (CLK) is a core component of the transcriptional feedback loops that comprise the circadian timekeeping mechanism in Drosophila. As a heterodimer with CYCLE (CYC), CLK binds E-boxes to activate the transcription of rhythmically expressed genes within and downstream of the circadian clock, but this activation unexpectedly occurs at times when CLK is at its lowest levels on Western blots. Recent studies demonstrate that CLK also regulates nonrhythmic gene expression and behaviors. Despite the critical roles CLK plays within and outside the circadian clock, its spatial expression pattern has not been characterized. Using a newly developed CLK antibody, the authors show that CLK is coexpressed with PERIOD (PER) in canonical oscillator cells throughout the head and body. In contrast to PER, however, the levels of CLK immunoreactivity do not cycle in intensity, CLK is detected primarily in the nucleus throughout the circadian cycle, and CLK is expressed in nonoscillator cells within the lateral and dorsal brain, including Kenyon cells, which mediate various forms of learning and memory. These results indicate that constitutive levels of nuclear CLK regulate rhythmic transcription in circadian oscillator cells and suggest that CLK contributes to other behavioral processes by regulating gene expression in nonoscillator cells.

Houl, Jerry H.; Yu, Wangjie; Dudek, Scott M.; Hardin, Paul E.

2006-01-01

38

Differential DNA methylation patterns in the CD86 gene controls its constitutive expression in keratinocytes.  

PubMed

The interaction of B7 family members with appropriate receptors is essential for an effective T cell response. CD80 and CD86 are the principal co-stimulatory molecules of this family and they are mainly expressed on professional antigen presenting cells (APCs), but also on several non-lymphoid cells. CD86 is constitutively expressed in keratinocytes from the spinous layer of normal cervical epithelium. However, the mechanisms that control the expression of this gene in epithelial cells remain unknown. We analyzed the DNA methylation status of the CD86 promoter and a CpG island located in the upstream intergenic region in keratinocyte-derived cell lines. In those cell lines where CD86 is expressed, a high degree of methylation in the CpG island was observed. However, a CpG dinucleotide within the cAMP response element (CRE) in the promoter region was consistently unmethylated and associated to the transcription factor CREB, as demonstrated by ChIP assays. The opposite methylation pattern was observed in cell lines where CD86 is not expressed, affecting also the binding of CREB. The analysis of the DNA methylation pattern of this gene in cells from the spinous and basal layers of normal cervical epithelium showed a similar profile to that observed in cell lines with and without expression of CD86 respectively. Our results indicate that the methylation pattern in the CD86 promoter and CpG island is closely related to the expression of this co-stimulatory molecule in keratinocytes. PMID:23867827

Romero-Tlalolini, M A; Chávez Olmos, P; Garrido, Efraín

2013-07-16

39

Integrating Constitutive Gene Expression and Chemoactivity: Mining the NCI60 Anticancer Screen  

PubMed Central

Studies into the genetic origins of tumor cell chemoactivity pose significant challenges to bioinformatic mining efforts. Connections between measures of gene expression and chemoactivity have the potential to identify clinical biomarkers of compound response, cellular pathways important to efficacy and potential toxicities; all vital to anticancer drug development. An investigation has been conducted that jointly explores tumor-cell constitutive NCI60 gene expression profiles and small-molecule NCI60 growth inhibition chemoactivity profiles, viewed from novel applications of self-organizing maps (SOMs) and pathway-centric analyses of gene expressions, to identify subsets of over- and under-expressed pathway genes that discriminate chemo-sensitive and chemo-insensitive tumor cell types. Linear Discriminant Analysis (LDA) is used to quantify the accuracy of discriminating genes to predict tumor cell chemoactivity. LDA results find 15% higher prediction accuracies, using ?30% fewer genes, for pathway-derived discriminating genes when compared to genes derived using conventional gene expression-chemoactivity correlations. The proposed pathway-centric data mining procedure was used to derive discriminating genes for ten well-known compounds. Discriminating genes were further evaluated using gene set enrichment analysis (GSEA) to reveal a cellular genetic landscape, comprised of small numbers of key over and under expressed on- and off-target pathway genes, as important for a compound’s tumor cell chemoactivity. Literature-based validations are provided as support for chemo-important pathways derived from this procedure. Qualitatively similar results are found when using gene expression measurements derived from different microarray platforms. The data used in this analysis is available at http://pubchem.ncbi.nlm.nih.gov/and http://www.ncbi.nlm.nih.gov/projects/geo (GPL96, GSE32474).

Covell, David G.

2012-01-01

40

Constitutively expressed DHAR and MDHAR influence fruit, but not foliar ascorbate levels in tomato.  

PubMed

Vitamin C (L-ascorbate, AsA) is an essential nutrient required in key metabolic functions in humans and must be obtained from the diet, mainly from fruits and vegetables. Given its importance in human health and plant physiology we sought to examine the role of the ascorbate recycling enzymes monodehydroascorbate reductase (MDHAR) and dehydroascorbate reductase (DHAR) in tomato (Solanum lycopersicum), an economically important fruit crop. Cytosolic-targeted tomato genes Mdhar and Dhar were cloned and over-expressed under a constitutive promoter in tomato var. Micro-Tom. Lines with increased protein levels and enzymatic activity were identified and examined. Mature green and red ripe fruit from DHAR over-expressing lines had a 1.6 fold increase in AsA content in plants grown under relatively low light conditions (150 ?mol m(-2) s(-1)). Conversely, MDHAR over-expressers had significantly reduced AsA levels in mature green fruits by 0.7 fold. Neither over-expressing line had altered levels of AsA in foliar tissues. These results underscore a complex regulation of the AsA pool size in tomato. PMID:21875809

Haroldsen, Victor M; Chi-Ham, Cecilia L; Kulkarni, Shashank; Lorence, Argelia; Bennett, Alan B

2011-08-17

41

Constitutive and allergen-induced expression of eotaxin mRNA in the guinea pig lung  

PubMed Central

Eotaxin is a member of the C-C family of chemokines and is related during antigen challenge in a guinea pig model of allergic airway inflammation (asthma). Consistent with its putative role in eosinophilic inflammation, eotaxin induces the selective infiltration of eosinophils when injected into the lung and skin. Using a guinea pig lung cDNA library, we have cloned full-length eotaxin cDNA. The cDNA encodes a protein of 96 amino acids, including a putative 23-amino acid hydrophobic leader sequence, followed by 73 amino acids composing the mature active eotaxin protein. The protein-coding region of this cDNA is 73, 71, 50, and 48% identical in nucleic acid sequence to those of human macrophage chemoattractant protein (MCP) 3, MCP-1, macrophage inflammatory protein (MIP) 1 alpha, and RANTES, respectively. Analysis of genomic DNA suggested that there is a single eotaxin gene in guinea pig which is apparently conserved in mice. High constitutive levels of eotaxin mRNA expression were observed in the lung, while the intestines, stomach, spleen, liver, heart, thymus, testes, and kidney expressed lower levels. To determine if eotaxin mRNA levels are elevated during allergen-induced eosinophilic airway inflammation, ovalbumin (OVA)-sensitized guinea pigs were challenged with aerosolized antigen. Compared with the lungs from saline-challenged animals, eotaxin mRNA levels increased sixfold within 3 h and returned to baseline by 6 h. Thus, eotaxin mRNA levels are increased in response to allergen challenge during the late phase response. The identification of constitutive eotaxin mRNA expression in multiple tissues suggests that in addition to regulating airway eosinophilia, eotaxin is likely to be involved in eosinophil recruitment into other tissues as well as in baseline tissue homing.

1995-01-01

42

Expression of constitutively active erythropoietin receptor in pyramidal neurons of cortex and hippocampus boosts higher cognitive functions in mice  

PubMed Central

Background Erythropoietin (EPO) and its receptor (EPOR) are expressed in the developing brain and their transcription is upregulated in adult neurons and glia upon injury or neurodegeneration. We have shown neuroprotective effects and improved cognition in patients with neuropsychiatric diseases treated with EPO. However, the critical EPO targets in brain are unknown, and separation of direct and indirect effects has remained difficult, given the role of EPO in hematopoiesis and brain oxygen supply. Results Here we demonstrate that mice with transgenic expression of a constitutively active EPOR isoform (cEPOR) in pyramidal neurons of cortex and hippocampus exhibit enhancement of spatial learning, cognitive flexibility, social memory, and attentional capacities, accompanied by increased impulsivity. Superior cognitive performance is associated with augmented long-term potentiation of cEPOR expressing neurons in hippocampal slices. Conclusions Active EPOR stimulates neuronal plasticity independent of any hematopoietic effects and in addition to its neuroprotective actions. This property of EPOR signaling should be exploited for defining novel strategies to therapeutically enhance cognitive performance in disease conditions.

2011-01-01

43

Constitutive TL1A (TNFSF15) Expression on Lymphoid or Myeloid Cells Leads to Mild Intestinal Inflammation and Fibrosis  

PubMed Central

TL1A is a member of the TNF superfamily and its expression is increased in the mucosa of inflammatory bowel disease patients. Moreover, a subset of Crohn's disease (CD) patients with the risk TL1A haplotype is associated with elevated TL1A expression and a more severe disease course. To investigate the in vivo role of elevated TL1A expression, we generated two transgenic (Tg) murine models with constitutive Tl1a expression in either lymphoid or myeloid cells. Compared to wildtype (WT) mice, constitutive expression of Tl1a in either lymphoid or myeloid cells showed mild patchy inflammation in the small intestine, which was more prominent in the ileum. In addition, mice with constitutive Tl1a expression exhibited enhanced intestinal and colonic fibrosis compared to WT littermates. The percentage of T cells expressing the gut homing chemokine receptors CCR9 and CCR10 was higher in the Tl1a Tg mice compared to WT littermates. Sustained expression of Tl1A in T cells also lead to increased Foxp3+ Treg cells. T cells or antigen presenting cells (APC) with constitutive expression of Tl1a were found to have a more activated phenotype and mucosal mononuclear cells exhibit enhanced Th1 cytokine activity. These results indicated an important role of TL1A in mucosal T cells and APC function and showed that up-regulation of TL1A expression can promote mucosal inflammation and gut fibrosis.

Shih, David Q.; Barrett, Robert; Zhang, Xiaolan; Yeager, Nicole; Koon, Hon Wai; Phaosawasdi, Piangwarin; Song, Yahui; Ko, Brian; Wong, Michelle H.; Michelsen, Kathrin S.; Martins, Gislaine; Pothoulakis, Charalabos; Targan, Stephan R.

2011-01-01

44

Expression of Constitutive Nitric Oxide Synthase Isoforms in Varicose Vein Wall; Preliminary Results  

PubMed Central

There are conflicting findings in literature about the structural changes of the primary varicose veins. NO (a potent vasodilatator) is synthesized by nitric oxide synthase (NOS). From 3 known NOS isoforms the two are constitutional: eNOS (endothelial NOS) and nNOS (neuronal NOS). 10 varicose and 10 control vein samples were processed by standard light microscopy and immuno-histochemica techniques using rabbit polyclonal antibodies against eNOS and nNOS. Antibodies expression was evaluated semiquantitatively and proved morphometrically by 2D-image analysis. total area of NOS isoforms expressions was determined by color analysis and color digital subtraction. The results showed discontinuous and significantly lower expression of both NOS isoforms the in the tunica media of varicose veins compared with the control group. For the statistical analysis the unpaired t-test was used. Our results suppose lower NO levels in varicose vein wall, deducing that varicose dilatation is due to other mechanism, and they contradict the results of previously published similar works.

Haviarova, Zora; Janegova, Andrea; Janega, Pavel; Durdik, Stefan; Kovac, Peter; Stvrtinova, Viera; Mraz, Peter

2011-01-01

45

Constitutively expressed Protocadherin-? regulates the coalescence and elimination of homotypic olfactory axons through its cytoplasmic region  

PubMed Central

Olfactory sensory neuron (OSN) axons coalesce into specific glomeruli in the olfactory bulb (OB) according to their odorant receptor (OR) expression. Several guidance molecules enhance the coalescence of homotypic OSN projections, in an OR-specific- and neural-activity-dependent manner. However, the mechanism by which homotypic OSN axons are organized into glomeruli is unsolved. We previously reported that the clustered protocadherin-? (Pcdh-?) family of diverse cadherin-related molecules plays roles in the coalescence and elimination of homotypic OSN axons throughout development. Here we showed that the elimination of small ectopic homotypic glomeruli required the constitutive expression of a Pcdh-? isoform and Pcdh-?'s cytoplasmic region, but not OR specificity or neural activity. These results suggest that Pcdh-? proteins provide a cytoplasmic signal to regulate repulsive activity for homotypic OSN axons independently of OR expression and neural activity. The counterbalancing effect of Pcdh-? proteins for the axonal coalescence mechanisms mediated by other olfactory guidance molecules indicate a possible mechanism for the organization of homotypic OSN axons into glomeruli during development.

Hasegawa, Sonoko; Hirabayashi, Takahiro; Kondo, Takahiko; Inoue, Ken; Esumi, Shigeyuki; Okayama, Atsushi; Hamada, Shun; Yagi, Takeshi

2012-01-01

46

Sensorimotor Gating Deficits in Transgenic Mice Expressing a Constitutively Active Form of Gs?  

PubMed Central

Schizophrenia is a complex disorder characterized by wide-ranging cognitive impairments, including deficits in learning as well as sensory gating. The causes of schizophrenia are unknown, but alterations in intracellular G-protein signaling pathways are among the molecular changes documented in patients with schizophrenia. Using the CaMKII? promoter to drive expression in neurons within the forebrain, we have developed transgenic mice that express a constitutively active form of Gs? (Gs?*), the G protein that couples receptors such as the D1 and D5 dopamine receptors to adenylyl cyclase. We have also generated mice in which the CaMKII? promoter drives expression of a dominant-negative form of protein kinase A, R(AB). Here, we examine startle responses and prepulse inhibition of the startle reflex (PPI) in these Gs?* and R(AB) transgenic mice. Gs?* transgenic mice exhibited selective deficits in PPI, without exhibiting alterations in the startle response, whereas no deficit in startle or PPI was found in the R(AB) transgenic mice. Thus, overstimulation of the cAMP/PKA pathway disrupts PPI, but the cAMP/PKA pathway may not be essential for sensorimotor gating. Gs?* transgenic mice may provide an animal model of certain endophenotypes of schizophrenia, because of the similarities between them and patients with schizophrenia in G-protein function, hippocampus-dependent learning, and sensorimotor gating.

Gould, Thomas J; Bizily, Scott P; Tokarczyk, Jan; Kelly, Michele P; Siegel, Steven J; Kanes, Stephen J; Abel, Ted

2012-01-01

47

Constitutive expression of the Period1 gene impairs behavioral and molecular circadian rhythms  

PubMed Central

Three mammalian Period (Per) genes, termed Per1, Per2, and Per3, have been identified as structural homologues of the Drosophila circadian clock gene, period (per). The three Per genes are rhythmically expressed in the suprachiasmatic nucleus (SCN), the central circadian pacemaker in mammals. The phases of peak mRNA levels for the three Per genes in the SCN are slightly different. Light sequentially induces the transcripts of Per1 and Per2 but not of Per3 in mice. These data and others suggest that each Per gene has a different but partially redundant function in mammals. To elucidate the function of Per1 in the circadian system in vivo, we generated two transgenic rat lines in which the mouse Per1 (mPer1) transcript was constitutively expressed under the control of either the human elongation factor-1? (EF-1?) or the rat neuron-specific enolase (NSE) promoter. The transgenic rats exhibited an ?0.6–1.0-h longer circadian period than their wild-type siblings in both activity and body temperature rhythms. Entrainment in response to light cycles was dramatically impaired in the transgenic rats. Molecular analysis revealed that the amplitudes of oscillation in the rat Per1 (rPer1) and rat Per2 (rPer2) mRNAs were significantly attenuated in the SCN and eyes of the transgenic rats. These results indicate that either the level of Per1, which is raised by overexpression, or its rhythmic expression, which is damped or abolished in over expressing animals, is critical for normal entrainment of behavior and molecular oscillation of other clock genes.

Numano, Rika; Yamazaki, Shin; Umeda, Nanae; Samura, Tomonori; Sujino, Mitsugu; Takahashi, Ri-ichi; Ueda, Masatsugu; Mori, Akiko; Yamada, Kazunori; Sakaki, Yoshiyuki; Inouye, Shin-Ichi T.; Menaker, Michael; Tei, Hajime

2006-01-01

48

Constitutive Expression of Thermobifida fusca Thermostable Acetylxylan Esterase Gene in Pichia pastoris  

PubMed Central

A gene encoding the thermostable acetylxylan esterase (AXE) in Thermobifida fusca NTU22 was amplified by PCR, sequenced and cloned into the Pichia pastoris X-33 host strain using the vector pGAPZ?A, allowing constitutive expression and secretion of the protein. Recombinant expression resulted in high levels of extracellular AXE production, as high as 526 U/mL in the Hinton flask culture broth. The purified enzyme showed a single band at about 28 kDa by SDS-polyacrylamide gel electrophoresis after being treated with endo-?-N-acetylglycosaminidase H; this agrees with the predicted size based on the nucleotide sequence. About 70% of the original activity remained after heat treatment at 60 °C for three hours. The optimal pH and temperature of the purified enzyme were 8.0 and 60 °C, respectively. The properties of the purified AXE from the P. pastoris transformant are similar to those of the AXE from an E. coli transformant.

Yang, Chao-Hsun; Lin, Kun-I; Chen, Gen-Hung; Chen, Yu-Fen; Chen, Cheng-Yu; Chen, Wei-Lin; Huang, Yu-Chun

2010-01-01

49

Constitutive expression of pea Lhcb 1–2 in tobacco affects plant development, morphology and photosynthetic capacity  

Microsoft Academic Search

Lhcb1–2 from pea was constitutively expressed in transgenic tobacco plants and assessed for functional impact. The successful assembly of the encoded proteins into LHCII trimers was confirmed by electrospray tandem mass spectrometry. Constitutive production of LHCb1–2 led to increased number of thylakoid membranes per chloroplast, increased grana stacking, higher chloroplast numbers per palisade cell and increased photosynthetic capacity at low

Mônica Labate; Kenton Ko; Zdenka Ko; Luciana Pinto; Maria Real; Marcelo Romano; Paulo Barja; Antonio Granell; Giulia Friso; Klaas Wijk; Enrico Brugnoli; Carlos Labate

2004-01-01

50

Islet ? cell expression of constitutively active Akt1/PKB? induces striking hypertrophy, hyperplasia, and hyperinsulinemia  

PubMed Central

The phosphoinositide 3-kinase–Akt/PKB pathway mediates the mitogenic effects various nutrients and growth factors in cultured cells. To study its effects in vivo in pancreatic islet ? cells, we created transgenic mice that expressed a constitutively active Akt1/PKB? linked to an Insulin gene promoter. Transgenic mice exhibited a grossly visible increase in islet mass, largely due to proliferation of insulin-containing ? cells. Morphometric analysis verified a six-fold increase in ? cell mass/pancreas, a two-fold increase in 5-bromo-2?-deoxyuridine incorporation, a four-fold increase in the number of ? cells per pancreas area, and a two-fold increase in cell size in transgenic compared with wild-type mice at 5 weeks. At least part of the increase in ? cell number may be accounted for by neogenesis, defined by criteria that include ? cells proliferating from ductular epithelium, and by a six-fold increase in the number of single and doublet ? cells scattered throughout the exocrine pancreas of the transgenic mice. Glucose tolerance was improved, and fasting as well as fed insulin was greater compared with wild-type mice. Glucose-stimulated insulin secretion was maintained in transgenic mice, which were resistant to streptozotocin–induced diabetes. We conclude that activation of the Akt1/PKB? pathway affects islet ? cell mass by alteration of size and number.

Bernal-Mizrachi, Ernesto; Wen, Wu; Stahlhut, Sarah; Welling, Cris M.; Permutt, M. Alan

2001-01-01

51

CD40 is constitutively expressed on platelets and provides a novel mechanism for platelet activation.  

PubMed

CD40 is a 48-kDa phosphorylated transmembrane glycoprotein belonging to the TNF receptor superfamily. CD40 has been demonstrated on a range of cell types, and it has an important role in adaptive immunity and inflammation. CD40 has recently been described on platelets but platelet activation by CD40 has not been described. In the present study, we use flow cytometry and immunoblotting to confirm that platelets constitutively express surface CD40. CD40 mRNA was undetectable, suggesting that the protein is synthesized early in platelet differentiation by megakaryocytes. Ligation of platelet CD40 with recombinant soluble CD40L trimer (sCD40LT) caused increased platelet CD62P expression, alpha-granule and dense granule release, and the classical morphological changes associated with platelet activation. CD40 ligation also caused beta3 integrin activation, although this was not accompanied by platelet aggregation. These actions were abrogated by the CD40L blocking antibody TRAP-1 and the CD40 blocking antibodies M2 and M3, showing that activation was mediated by CD40L binding to platelet CD40. beta3 integrin blockade with eptifibatide had no effect, indicating that outside-in signaling via alphaIIbbeta3 was not contributing to these CD40-mediated effects. CD40 ligation led to enhanced platelet-leukocyte adhesion, which is important in the recruitment of leukocytes to sites of thrombosis or inflammation. Our results support a role for CD40-mediated platelet activation in thrombosis, inflammation, and atherosclerosis. PMID:12676820

Inwald, David P; McDowall, Alison; Peters, Mark J; Callard, Robin E; Klein, Nigel J

2003-04-03

52

Constitutive expression of a complement-like protein in Toll and JAK gain-of-function mutants of Drosophila  

PubMed Central

We show that Drosophila expresses four genes encoding proteins with significant similarities with the thiolester-containing proteins of the complement C3/?2-macroglobulin superfamily. The genes are transcribed at a low level during all stages of development, and their expression is markedly up-regulated after an immune challenge. For one of these genes, which is predominantly expressed in the larval fat body, we observe a constitutive expression in gain-of-function mutants of the Janus kinase (JAK) hop and a reduced inducibility in loss-of-function hop mutants. We also observe a constitutive expression in gain-of-function Toll mutants. We discuss the possible roles of these novel complement-like proteins in the Drosophila host defense.

Lagueux, Marie; Perrodou, Emmanuel; Levashina, Elena A.; Capovilla, Maria; Hoffmann, Jules A.

2000-01-01

53

The constitutive AHSB4 promoter--a novel component of the Arxula adeninivorans-based expression platform.  

PubMed

An Arxula adeninivorans-AHSB4 gene, encoding histone H4, was isolated and characterized. The gene includes a coding sequence of 363 bp disrupted by a 51-bp intron, similar to the situation in other fungal H4 genes. The identity of the gene was confirmed by the high degree of homology of the derived amino acid sequence with that of other H4 histones. The gene is strongly and constitutively expressed, maintaining this expression profile under salt-stress conditions. The AHSB4 promoter was tested for suitability in heterologous gene expression using genes encoding the intracellular green fluorescent protein and the secreted human serum albumin (HSA) for assessment. Plasmids incorporating respective expression cassettes were used to transform the host strain A. adeninivorans LS3, which forms budding cells at 30 degrees C, and strain 135, which forms mycelia under these conditions. Transformants of both types were found to harbor a single copy of the heterologous DNA. Strong constitutive expression was observed during culture in salt-containing and salt-free media, as expected from the expression profile of AHSB4. In 200-ml shake-flask cultures, maximal HSA levels of 20 mg l(-1) culture medium were achieved. This productivity could be increased to 50 mg l(-1 )in strains harboring two copies of the expression cassette. The AHSB4 promoter thus provides an attractive component for constitutive heterologous gene expression under salt-free and salt-stress conditions. PMID:12733004

Wartmann, T; Bellebna, C; Böer, E; Bartelsen, O; Gellissen, G; Kunze, G

2003-05-06

54

Constitutive Expression and Enzymatic Cleavage of ICAM-1 in the Spontaneously Hypertensive Rat  

PubMed Central

Background/Aims: Leukocyte adhesion to the endothelium is abnormal in hypertension. We have recently shown that spontaneously hypertensive rats (SHRs) have circulating leukocytes with enhanced CD18 receptor cleavage. In the current study, we investigate expression levels of its counter receptor, intercellular adhesion molecule (ICAM-1), and its possible proteolytic cleavage in the SHR and control Wistar rat. Methods ICAM-1 was labeled on tissue sections with two antibodies targeting its extracellular and intracellular domains and evaluated by light absorption measurements. The in situ cleavage of ICAM-1 was assessed by treating vessel sections with matrix metalloproteinase (MMP)-7, MMP-9 and elastase. Results SHRs showed a significant increase in ICAM-1 expression in liver and kidney compared with Wistar rats. The liver and kidney glomeruli exhibit a discrepancy in label density between intra- and extracellular antibodies, which suggests that enzymatic cleavage may be a factor determining ICAM-1 distribution. MMP-7 and MMP-9, which are elevated in SHR plasma, and elastase, which has elevated activity in SHR neutrophils, cleave the extracellular domain of ICAM-1 when applied to the tissue. Conclusion ICAM-1 expression in SHRs is upregulated in a tissue-specific manner. Proteolytic cleavage of the extracellular domain of ICAM-1 and accumulation in kidney glomeruli may play a role in the renal involvement of inflammation.

Tong, Sheng; Neboori, Hanmanth J.; Tran, Edward D.; Schmid-Schonbein, Geert W.

2011-01-01

55

Constitutive expression of a grapevine polygalacturonase-inhibiting protein affects gene expression and cell wall properties in uninfected tobacco  

PubMed Central

Background Polygalacturonase-inhibiting proteins (PGIPs) directly limit the effective ingress of fungal pathogens by inhibiting cell wall-degrading endopolygalacturonases (ePGs). Transgenic tobacco plants over-expressing grapevine (Vitis vinifera) Vvpgip1 have previously been shown to be resistant to Botrytis infection. In this study we characterized two of these PGIP over-expressing lines with known resistance phenotypes by gene expression and hormone profiling in the absence of pathogen infection. Results Global gene expression was performed by a cross-species microarray approach using a potato cDNA microarray. The degree of potential cross-hybridization between probes was modeled by a novel computational workflow designed in-house. Probe annotations were updated by predicting probe-to-transcript hybridizations and combining information derived from other plant species. Comparing uninfected Vvpgip1-overexpressing lines to wild-type (WT), 318 probes showed significant change in expression. Functional groups of genes involved in metabolism and associated to the cell wall were identified and consequent cell wall analysis revealed increased lignin-levels in the transgenic lines, but no major differences in cell wall-derived polysaccharides. GO enrichment analysis also identified genes responsive to auxin, which was supported by elevated indole-acetic acid (IAA) levels in the transgenic lines. Finally, a down-regulation of xyloglucan endotransglycosylase/hydrolases (XTHs), which are important in cell wall remodeling, was linked to a decrease in total XTH activity. Conclusions This evaluation of PGIP over-expressing plants performed under pathogen-free conditions to exclude the classical PGIP-ePG inhibition interaction indicates additional roles for PGIPs beyond the inhibition of ePGs.

2011-01-01

56

Human small intestinal epithelial cells constitutively express the key elements for antigen processing and the production of exosomes  

Microsoft Academic Search

In humans, the small intestinal epithelial cells (IEC) have a high constitutive expression of MHC class II (MHC II), and contains lysosomes. The IEC also contains MHC II rich multivesicular compartments and has been shown to produce exosomes. This suggests a role for the IEC in antigen processing and presentation either directly or indirectly by the production of exosomes. However,

X. P. Lin; N. Almqvist; E. Telemo

2005-01-01

57

Rhizoremediation of Trichloroethylene by a Recombinant, Root-Colonizing Pseudomonas fluorescens Strain Expressing Toluene ortho-Monooxygenase Constitutively  

Microsoft Academic Search

Trichloroethylene (TCE) was removed from soils by using a wheat rhizosphere established by coating seeds with a recombinant, TCE-degrading Pseudomonas fluorescens strain that expresses the tomA1 (toluene o-mono- oxygenase) genes from Burkholderia cepacia PR123(TOM23C). A transposon integration vector was used to insert tomA1 into the chromosome of P. fluorescens 2-79, producing a stable strain that expressed constitutively the monooxygenase at

DENNIS C. YEE; JENNIFER A. MAYNARD; THOMAS K. WOOD

1998-01-01

58

Constitutive expression, purification and characterization of a phosphoglucomutase from Fusarium oxysporum.  

PubMed

The phosphoglucomutase gene from a wild type Fusarium oxysporum strain (F3), was homologously expressed, under the control of the constitutive promoter of gpdA of Aspergillus nidulans. The transformant produced elevated levels of phosphoglucomutase activity compared to the wild type, a fact that facilitated the subsequent purification procedure. The enzyme (FoPGM) was purified to homogeneity applying three anion exchange and one gel filtration chromatography steps. The native enzyme revealed a monomeric structure with a molecular mass of 60 kDa, while the isoelectric point was 3.5. FoPGM was active in pH ranged from 6.0 to 8.0, with an optimum using 3-(N-morpholino)propanesulfonic acid buffer at 7.0, while loss of activity was observed when phosphate buffer was used in the above mentioned pH range. The optimal temperature for activity was 45°C but the enzyme became unstable at temperatures above 40°C. FoPGM requires the presence of a divalent cation for its function with maximum activity being obtained with Co(2+). The apparent K(m) for Co(2+) was found to be 10 ?M. The enzyme was also active with other divalent metal ions such as Mn(2+), Mg(2+), Ni(2+) and Ca(2+) but to a lesser extent. The following kinetic constants were determined: v(max), 0.74 ?mol mg(protein)(-1)min(-1); k(cat), 44.2 min(-1); K(m)(G1P), 0.10mM; K(m)(G1,6 diP), 1.03 ?M; k(cat)/K(m)(G1P), 443 mM(-1)min(-1) and k(cat)/K(m)(G1,6 diP), 42,860 mM(-1)min(-1). The enzyme was considered to follow a Ping Pong substituted enzyme or enzyme isomerization mechanism. PMID:22112903

Kourtoglou, Elisavet; Anasontzis, George E; Mamma, Diomi; Topakas, Evangelos; Hatzinikolaou, Dimitris G; Christakopoulos, Paul

2010-12-01

59

Signal transducer and activator of transcription 1 negatively regulates constitutive gamma interferon-inducible lysosomal thiol reductase expression.  

PubMed

Gamma interferon-inducible lysosomal thiol reductase (GILT) is an enzyme that catalyzes thiol bond reduction and plays an important role in the early steps of antigen processing. The key factor involved in the regulation of GILT expression upon cell stimulation with interferon-? (IFN-?) is signal transducer and activator of transcription 1 (STAT1). In this study, we examined the role of STAT1 in regulating the constitutive expression of GILT. We showed that STAT1 interacts with the GILT promoter, even in the absence of IFN-?, and that STAT1 represses GILT expression. These results reveal an atypical negative regulatory role for STAT1 in the constitutive regulation of genes involved in antigen processing. PMID:21039465

Srinivasan, Priya; Maric, Maja

2010-10-13

60

Signal transducer and activator of transcription 1 negatively regulates constitutive gamma interferon-inducible lysosomal thiol reductase expression  

PubMed Central

Gamma interferon-inducible lysosomal thiol reductase (GILT) is an enzyme that catalyzes thiol bond reduction and plays an important role in the early steps of antigen processing. The key factor involved in the regulation of GILT expression upon cell stimulation with interferon-? (IFN-?) is signal transducer and activator of transcription 1 (STAT1). In this study, we examined the role of STAT1 in regulating the constitutive expression of GILT. We showed that STAT1 interacts with the GILT promoter, even in the absence of IFN-?, and that STAT1 represses GILT expression. These results reveal an atypical negative regulatory role for STAT1 in the constitutive regulation of genes involved in antigen processing.

Srinivasan, Priya; Maric, Maja

2011-01-01

61

Multiple effects of genetic background on variegated transgene expression in mice.  

PubMed

BLG/7 transgenic mice express an ovine beta-lactoglobulin transgene during lactation. Unusually, transgene expression levels in milk differ between siblings. This variable expression is due to variegated transgene expression in the mammary gland and is reminiscent of position-effect variegation. The BLG/7 line was created and maintained on a mixed CBA x C57BL/6 background. We have investigated the effect on transgene expression of backcrossing for 13 generations into these backgrounds. Variable transgene expression was observed in all populations examined, confirming that it is an inherent property of the transgene array at its site of integration. There were also strain-specific effects on transgene expression that appear to be independent of the inherent variegation. The transgene, compared to endogenous milk protein genes, is specifically susceptible to inbreeding depression. Outcrossing restored transgene expression levels to that of the parental population; thus suppression was not inherited. Finally, no generation-dependent decrease in mean expression levels was observed in the parental population. Thus, although the BLG/7 transgene is expressed in a variegated manner, there was no generation-associated accumulated silencing of transgene expression. PMID:11901126

Opsahl, Margaret L; McClenaghan, Margaret; Springbett, Anthea; Reid, Sarah; Lathe, Richard; Colman, Alan; Whitelaw, C Bruce A

2002-03-01

62

Multiple effects of genetic background on variegated transgene expression in mice.  

PubMed Central

BLG/7 transgenic mice express an ovine beta-lactoglobulin transgene during lactation. Unusually, transgene expression levels in milk differ between siblings. This variable expression is due to variegated transgene expression in the mammary gland and is reminiscent of position-effect variegation. The BLG/7 line was created and maintained on a mixed CBA x C57BL/6 background. We have investigated the effect on transgene expression of backcrossing for 13 generations into these backgrounds. Variable transgene expression was observed in all populations examined, confirming that it is an inherent property of the transgene array at its site of integration. There were also strain-specific effects on transgene expression that appear to be independent of the inherent variegation. The transgene, compared to endogenous milk protein genes, is specifically susceptible to inbreeding depression. Outcrossing restored transgene expression levels to that of the parental population; thus suppression was not inherited. Finally, no generation-dependent decrease in mean expression levels was observed in the parental population. Thus, although the BLG/7 transgene is expressed in a variegated manner, there was no generation-associated accumulated silencing of transgene expression.

Opsahl, Margaret L; McClenaghan, Margaret; Springbett, Anthea; Reid, Sarah; Lathe, Richard; Colman, Alan; Whitelaw, C Bruce A

2002-01-01

63

Hypoxia reduces constitutive and TNF-{alpha}-induced expression of monocyte chemoattractant protein-1 in human proximal renal tubular cells  

SciTech Connect

Chronic hypoxia has been reported to be associated with macrophage infiltration in progressive forms of kidney disease. Here, we investigated the regulatory effects of hypoxia on constitutive and TNF-{alpha}-stimulated expression of monocyte chemoattractant protein-1 (MCP-1) in cultured human proximal renal tubular cells (HPTECs). Hypoxia reduced constitutive MCP-1 expression at the mRNA and protein levels in a time-dependent fashion for up to 48 h. Hypoxia also inhibited MCP-1 up-regulation by TNF-{alpha}. Treatment with actinomycin D showed that hypoxic down-regulation of MCP-1 expression resulted mainly from a decrease in the transcription but not the mRNA stability. Immunoblot and immunofluorescence analyses revealed that treatment with hypoxia or an iron chelator, desferrioxamine, induced nuclear accumulation of hypoxia-inducible factor-1{alpha} (HIF-1{alpha}) in HPTECs. Desferrioxamine mimicked hypoxia in the reduction of MCP-1 expression. However, overexpression of a dominant negative form of HIF-1{alpha} did not abolish the hypoxia-induced reduction of MCP-1 expression in HPTECs. These results suggest that hypoxia is an important negative regulator of monocyte chemotaxis to the renal inflamed interstitium, by reducing MCP-1 expression partly via hypoxia-activated signals other than the HIF-1 pathway.

Li Xuan [Division of Nephrology, Department of General Medicine, School of Medicine, Faculty of Medical Sciences, University of Fukui, Fukui (Japan); Kimura, Hideki [Division of Nephrology, Department of General Medicine, School of Medicine, Faculty of Medical Sciences, University of Fukui, Fukui (Japan)]. E-mail: hkimura@fmsrsa.fukui-med.ac.jp; Hirota, Kiichi [Department of Anesthesia, Tazuke Kofukai Medical Research Institute Kitano Hospital, Osaka (Japan); Department of Anesthesia, School of Medicine, Kyoto University, Kyoto (Japan); Sugimoto, Hidehiro [Division of Nephrology, Department of General Medicine, School of Medicine, Faculty of Medical Sciences, University of Fukui, Fukui (Japan); Yoshida, Haruyoshi [Division of Nephrology, Department of General Medicine, School of Medicine, Faculty of Medical Sciences, University of Fukui, Fukui (Japan)

2005-10-07

64

Adeno-associated virus vector-mediated expression and constitutive secretion of galanin suppresses limbic seizure activity.  

PubMed

Theoretically, gene therapy techniques offer an attractive alternative treatment option for intractable, focal epilepsies. Although logical gene therapy targets include excitatory and inhibitory receptors, variable viral vector tropism interjects an uncertainty as to the direction of change, seizure suppression, or seizure sensitization. To circumvent this therapeutic liability, adeno-associated virus (AAV) vectors have been constructed where the gene product is constitutively secreted from the transduced cell. Using AAV vectors, the fibronectin secretory signal sequence (FIB) was placed in front of the coding sequence for green fluorescent protein or the active portion of the neuroactive peptide galanin (GAL). Subsequent studies showed that these vectors supported expression and constitutive secretion of these gene products from transfected cells in vitro. More importantly, upon transduction in vivo, AAV-FIB-GAL vectors significantly attenuated focal seizure sensitivity, and this seizure attenuation could be controlled in vivo by using a tetracycline-regulated promoter. The expression and constitutive secretion of green fluorescent protein, or the expression of GAL alone, exerted no effect on focal seizure sensitivity. Moreover, unilateral infusion of the AAV-FIB-GAL vectors into the hippocampus prevented kainic acid-induced hilar cell death. With regard to limbic seizures, bilateral infusion of AAV-FIB-GAL vectors into the piriform cortex prevented both behavioral and localized electrographic seizure activity after the peripheral administration of kainic acid. Also, when rats were electrically kindled to class V seizure activity, subsequent infusion of AAV-FIB-GAL proved capable of significantly elevating the seizure initiation threshold. Thus, these studies clearly demonstrate the anti-seizure effectiveness of AAV vector-mediated expression and constitutive secretion of galanin. PMID:19332324

McCown, Thomas J

2009-04-01

65

Expression of constitutively activated Akt in the mammary gland leads to excess lipid synthesis during pregnancy and lactation  

Microsoft Academic Search

Expression of constitutively activated Akt in the mammary glands of transgenic mice results in a delay in post-lactational involution. We now report precocious lipid accumulation in the alveolar epithelium of mouse mam- mary tumor virus-myr-Akt transgenic mice accompanied by a lactation defect that results in a 50% decrease in litter weight over the first 9 days of lactation. Although ductal

Kathryn L. Schwertfeger; James L. McManaman; Carol A. Palmer; Margaret C. Neville; Steven M. Anderson

2003-01-01

66

Constitutive andRetinoic Acid-Inducible Expression of Cytomegalovirus Immediate-Early GenesinHuman Teratocarcinoma Cells  

Microsoft Academic Search

polypeptide (68Kpolypeptide) was notexpressed, andconsequently inputviral genomes were notreplicated. However,afterdifferentiation ofthe teratocarcinoma cells, synthesis oftheHCMV IE68Kpolypeptide was induced, andviral DNA replication occurred. Incontrast toourobservations forHCMV,simian cytomegalovirus (SCMV)displayed constitutive expression ofitsanalogous IE94Kpolypeptide, andtheinput SCMV genomes were replicated inboth uninduced stemcells and293cells. Sincelittle, ifany, HCMV IE RNA was detectable inhuman teratocarcinoma or293cells after infection underIEconditions, we suggest that adirect transcriptional block topermissivity

ROBERT LAFEMINA; GARY S. HAYWARD

1986-01-01

67

Human Keratinocytes In Vivo and In Vitro Constitutively Express The 72-kD Heat Shock Protein  

Microsoft Academic Search

Exposure of cells to elevated temperatures induces a physiologic response characterized by the synthesis of a specific set of proteins (heat shock or stress proteins, HSPs) mediating repair mechanisms and protection from cellular damage. In the present study upon immunohistochemistry using a specific monoclonal antibody, the constitutive and heat-induced expression of the 72-kD HSP (HSP72) in normal human skin and

F. Trautinger; I. Trautinger; I. Kindas-Mugge; D. Metze; T. A. Luger

1993-01-01

68

Revealing constitutively expressed resistance genes in Agrostis species using PCR-based motif-directed RNA fingerprinting.  

PubMed

Agrostis species are mainly used in athletic fields and golf courses. Their integrity is maintained by fungicides, which makes the development of disease-resistance varieties a high priority. However, there is a lack of knowledge about resistance (R) genes and their use for genetic improvement in Agrostis species. The objective of this study was to identify and clone constitutively expressed cDNAs encoding R gene-like (RGL) sequences from three Agrostis species (colonial bentgrass (A. capillaris L.), creeping bentgrass (A. stolonifera L.) and velvet bentgrass (A. canina L.)) by PCR-based motif-directed RNA fingerprinting towards relatively conserved nucleotide binding site (NBS) domains. Sixty-one constitutively expressed cDNA sequences were identified and characterized. Sequence analysis of ESTs and probable translation products revealed that RGLs are highly conserved among these three Agrostis species. Fifteen of them were shown to share conserved motifs found in other plant disease resistance genes such as MLA13, Xa1, YR6, YR23 and RPP5. The molecular evolutionary forces, analysed using the Ka/Ks ratio, reflected purifying selection both on NBS and leucine-rich repeat (LRR) intervening regions of discovered RGL sequences in these species. This study presents, for the first time, isolation and characterization of constitutively expressed RGL sequences from Agrostis species revealing the presence of TNL (TIR-NBS-LRR) type R genes in monocot plants. The characterized RGLs will further enhance knowledge on the molecular evolution of the R gene family in grasses. PMID:17371611

Budak, Hikmet; Su, Senem; Ergen, Neslihan

2006-12-01

69

Constitutive activity of the cannabinoid CB1 receptor regulates the function of co-expressed Mu opioid receptors.  

PubMed

The human mu opioid receptor was expressed stably in Flp-In T-REx HEK293 cells. Occupancy by the agonist DAMGO (Tyr-d-Ala-Gly-N-methyl-Phe-Gly-ol) resulted in phosphorylation of the ERK1/2 MAP kinases, which was blocked by the opioid antagonist naloxone but not the cannabinoid CB1 receptor inverse agonist SR141716A. Expression of the human cannabinoid CB1 receptor in these cells from the inducible Flp-In T-REx locus did not alter expression levels of the mu opioid receptor. This allowed the cannabinoid CB1 agonist WIN55212-2 to stimulate ERK1/2 phosphorylation but resulted in a large reduction in the capacity of DAMGO to activate these kinases. Although lacking affinity for the mu opioid receptor, co-addition of SR141716A caused recovery of the effectiveness of DAMGO. In contrast co-addition of the CB1 receptor neutral antagonist O-2050 did not. Induction of the CB1 receptor also resulted in an increase of basal [(35)S]guanosine 5'-3-O-(thio)triphosphate (GTPgammaS) binding and thereby a greatly reduced capacity of DAMGO to further stimulate [(35)S]GTPgammaS binding. CB1 inverse agonists attenuated basal [(35)S]GTPgammaS binding and restored the capacity of DAMGO to stimulate. Flp-In T-REx HEK293 cells were generated, which express the human mu opioid receptor constitutively and harbor a modified D163N cannabinoid CB1 receptor that lacks constitutive activity. Induction of expression of the modified cannabinoid CB1 receptor did not limit DAMGO-mediated ERK1/2 MAP kinase phosphorylation and did not allow SR141716A to enhance the function of DAMGO. These data indicate that it is the constitutive activity inherent in the cannabinoid CB1 receptor that reduces the capacity of co-expressed mu opioid receptor to function. PMID:18319252

Canals, Meritxell; Milligan, Graeme

2008-03-04

70

Stable expression of constitutively-activated STAT3 in benign prostatic epithelial cells changes their phenotype to that resembling malignant cells  

PubMed Central

Background Signal transducers and activators of transcription (STATs) are involved in growth regulation of cells. They are usually activated by phosphorylation at specific tyrosine residues. In neoplastic cells, constitutive activation of STATs accompanies growth dysregulation and resistance to apoptosis through changes in gene expression, such as enhanced anti-apoptotic gene expression or reduced pro-apoptotic gene expression. Activated STAT3 is thought to play an important role in prostate cancer (PCA) progression. Because we are interested in how persistently-activated STAT3 changes the cellular phenotype to a malignant one in prostate cancer, we used expression vectors containing a gene for constitutively-activated STAT3, called S3c, into NRP-152 rat and BPH-1 human benign prostatic epithelial cells. Results We observed that prostatic cell lines stably expressing S3c required STAT3 expression for survival, because they became sensitive to antisense oligonucleotide for STAT3. However, S3c-transfected cells were not sensitive to the effects of JAK inhibitors, meaning that STAT3 was constitutively-activated in these transfected cell lines. NRP-152 prostatic epithelial cells lost the requirement for exogenous growth factors. Furthermore, we observed that NRP-152 expressing S3c had enhanced mRNA levels of retinoic acid receptor (RAR)-?, reduced mRNA levels of RAR-? and -?, while BPH-1 cells transfected with S3c became insensitive to the effects of androgen, and also to the effects of a testosterone antagonist. Both S3c-transfected cell lines grew in soft agar after stable transfection with S3c, however neither S3c-transfected cell line was tumorigenic in severe-combined immunodeficient mice. Conclusions We conclude, based on our findings, that persistently-activated STAT3 is an important molecular marker of prostate cancer, which develops in formerly benign prostate cells and changes their phenotype to one more closely resembling transformed prostate cells. That the S3c-transfected cell lines require the continued expression of S3c demonstrates that a significant phenotypic change occurred in the cells. These conclusions are based on our data with respect to loss of growth factor requirement, loss of androgen response, gain of growth in soft agar, and changes in RAR subunit expression, all of which are consistent with a malignant phenotype in prostate cancer. However, an additional genetic change may be required for S3c-transfected prostate cells to become tumorigenic.

Huang, Hosea F; Murphy, Thomas F; Shu, Ping; Barton, Arnold B; Barton, Beverly E

2005-01-01

71

Constitutive activation of the gastrin-releasing peptide receptor expressed by the nonmalignant human colon epithelial cell line NCM460.  

PubMed Central

Gastrin-releasing peptide (GRP) causes multiple effects in humans by activating a specific heptaspanning receptor. Within the gastrointestinal tract, GRP receptors (GRP-R) are not normally expressed by mucosal epithelial cells except for those lining the gastric antrum. In contrast, recent studies have shown that up to 40% of resected colon cancers aberrantly express this receptor. This is important because the GRP-R can cause the proliferation of many, but not all, tissues in which it is expressed. Since GRP and other agonists are not known to exist in the colonic lumen, it has not been clear how or even if GRP-R expression in colon cancer contributes to cell proliferation. To evaluate the functional consequence of GRP-R expression on colonic epithelium, we transfected the recently isolated nonmalignant human colon epithelial cell line NCM460 with the cDNA for this receptor. All NCM460 cell lines expressing varying numbers of GRP-R bound selected agonists and antagonists indistinguishably from receptors expressed by other human tissues. Furthermore GRP-R-expressing transfected cell lines, but not wild-type NCM460 cells, proliferated independently of serum or other growth factors. Further evaluation revealed that GRP-R in these cells tonically stimulated G alpha q/11, resulting in increased phospholipase C activation. Since transfected cells do not secrete GRP, nor is their growth influenced by exposure to receptor-specific antagonists, these data indicate that GRP-R ectopically expressed by NCM460 cells are constitutively active. This report provides the first evidence of mutation-independent heptaspanning receptor constitutive activation resulting in cell proliferation, and identifies a potential mechanism whereby the GRP-R may act as an oncogene in human colon cancer.

Ferris, H A; Carroll, R E; Rasenick, M M; Benya, R V

1997-01-01

72

Thyroglobulin Repression of Thyroid Transcription Factor 1 (TTF-1) Gene Expression Is Mediated by Decreased DNA Binding of Nuclear Factor I Proteins Which Control Constitutive TTF-1 Expression  

PubMed Central

Follicular thyroglobulin (TG) selectively suppresses the expression of thyroid-restricted transcription factors, thereby altering the expression of thyroid-specific proteins. In this study, we investigated the molecular mechanism by which TG suppresses the prototypic thyroid-restricted transcription factor, thyroid transcription factor 1 (TTF-1), in rat FRTL-5 thyrocytes. We show that the region between bp ?264 and ?153 on the TTF-1 promoter contains two nuclear factor I (NFI) elements whose function is involved in TG-mediated suppression. Thus, NFI binding to these elements is critical for constitutive expression of TTF-1; TG decreases NFI binding to the NFI elements in association with TG repression. NFI is a family of transcription factors that is ubiquitously expressed and contributes to constitutive and cell-specific gene expression. In contrast to the contribution of NFI proteins to constitutive gene expression in other systems, we demonstrate that follicular TG transcriptionally represses all NFI RNAs (NFI-A, -B, -C, and -X) in association with decreased NFI binding and that the RNA levels decrease as early as 4 h after TG treatment. Although TG treatment for 48 h results in a decrease in NFI protein-DNA complexes measured in DNA mobility shift assays, NFI proteins are still detectable by Western analysis. We show, however, that the binding of all NFI proteins is redox regulated. Thus, diamide treatment of nuclear extracts strongly reduces the binding of NFI proteins, and the addition of higher concentrations of dithiothreitol to nuclear extracts from TG-treated cells restores NFI-DNA binding to levels in extracts from untreated cells. We conclude that NFI binding to two NFI elements, at bp ?264 to ?153, positively regulates TTF-1 expression and controls constitutive TTF-1 levels. TG mediates the repression of TTF-1 gene expression by decreasing NFI RNA and protein levels, as well as by altering the binding activity of NFI, which is redox controlled.

Nakazato, Minoru; Chung, Hyun-Kyung; Ulianich, Luca; Grassadonia, Antonino; Suzuki, Koichi; Kohn, Leonard D.

2000-01-01

73

Tissue-specific expression of inducible and constitutive Hsp70 isoforms in the western painted turtle.  

PubMed

Expression of Hsp73 and Hsp72 in four tissues of the naturally anoxia-tolerant western painted turtle (Chrysemys picta) was investigated in response to a 24 h forced dive and following 1 h recovery. Of the tissues examined, brain and liver displayed approximately threefold and sevenfold higher basal Hsp73 expression than heart and skeletal muscle. Basal Hsp72 expression was relatively low in all tissues examined. After the 24 h forced dive and 1 h recovery, Hsp73 expression did not differ significantly from basal expression with the exception of liver, where expression decreased significantly after 1 h recovery. Hsp72 expression was unchanged in liver following a 24 h dive; however, it increased twofold in brain and threefold in heart and skeletal muscle. Dive-induced Hsp72 expression was found to correlate inversely with basal Hsp73 expression. Following 1 h recovery, Hsp72 expression was significantly elevated in all tissues above levels in dived animals. These data indicate a tissue-specific pattern of Hsp73 and Hsp72 expression in the western painted turtle during both unstressed and stressed conditions. PMID:12477900

Scott, Michelle Anne; Locke, Marius; Buck, Leslie Thomas

2003-01-01

74

Constitutive activation of gene expression by thyroid hormone receptor results from reversal of p53-mediated repression.  

PubMed Central

Thyroid hormone receptor (T3R) is a member of the steroid hormone receptor gene family of nuclear hormone receptors. In most cells T3R activates gene expression only in the presence of its ligand, L-triiodothyronine (T3). However, in certain cell types (e.g., GH4C1 cells) expression of T3R leads to hormone-independent constitutive activation. This activation by unliganded T3R occurs with a variety of gene promoters and appears to be independent of the binding of T3R to specific thyroid hormone response elements (TREs). Previous studies indicate that this constitutive activation results from the titration of an inhibitor of transcription. Since the tumor suppresser p53 is capable of repressing a wide variety of gene promoters, we considered the possibility that the inhibitor is p53. Evidence to support this comes from studies indicating that expression of p53 blocks T3R-mediated constitutive activation in GH4C1 cells. In contrast with hormone-independent activation by T3R, p53 had little or no effect on T3-dependent stimulation which requires TREs. In addition, p53 mutants which oligomerize with wild-type p53 and interfere with its function also increase promoter activity. This enhancement is of similar magnitude to but is not additive with the stimulation mediated by unliganded T3R, suggesting that they target the same factor. Since p53 mutants are known to target wild-type p53 in the cell, this suggests that T3R also interacts with p53 in vivo and that endogenous levels of p53 act to suppress promoter activity. Evidence supporting both functional and physical interactions of T3R and p53 in the cell is presented. The DNA binding domain (DBD) of T3R is important in mediating constitutive activation, and the receptor DBD appears to functionally interact with the N terminus of p53 in the cell. In vitro binding studies indicate that the T3R DBD is important for interaction of T3R with p53 and that this interaction is reduced by T3. These findings are consistent with the in vivo studies indicating that p53 blocks constitutive activation but not ligand-dependent stimulation. These studies provide insight into mechanisms by which unliganded nuclear hormone receptors can modulate gene expression and may provide an explanation for the mechanism of action of the v-erbA oncoprotein, a retroviral homolog of chicken T3R alpha.

Qi, J S; Desai-Yajnik, V; Yuan, Y; Samuels, H H

1997-01-01

75

Mast cell hyperplasia, B-cell malignancy, and intestinal inflammation in mice with conditional expression of a constitutively active kit.  

PubMed

Signaling through the receptor tyrosine kinase kit controls proliferation and differentiation of hematopoietic precursor cells and mast cells. Somatic point mutations of the receptor that constitutively activate kit signaling are associated with mastocytosis and various hematopoietic malignancies. We generated a Cre/loxP-based bacterial artificial chromosome transgenic mouse model that allows conditional expression of a kit gene carrying the kitD814V mutation (the murine homolog of the most common mutation in human mastocytosis, kitD816V) driven by the kit promoter. Expression of the mutant kit in cells of adult mice, including hematopoietic precursors, caused severe mastocytosis with 100% penetrance at young age frequently associated with additional hematopoietic (mostly B lineage-derived) neoplasms and focal colitis. Restriction of transgene expression to mature mast cells resulted in a similar mast cell disease developing with slower kinetics. Embryonic expression led to a hyperproliferative dysregulation of the erythroid lineage with a high rate of perinatal lethality. In addition, most adult animals developed colitis associated with mucosal mast cell accumulation. Our findings demonstrate that the effects of constitutive kit signaling critically depend on the developmental stage and the state of differentiation of the cell hit by the gain-of-function mutation. PMID:21148330

Gerbaulet, Alexander; Wickenhauser, Claudia; Scholten, Julia; Peschke, Katrin; Drube, Sebastian; Horny, Hans-Peter; Kamradt, Thomas; Naumann, Ronald; Müller, Werner; Krieg, Thomas; Waskow, Claudia; Hartmann, Karin; Roers, Axel

2010-12-09

76

Constitutive and induced expression by pyridine and ?-naphthoflavone of rat CYP1A is sexually dimorphic  

Microsoft Academic Search

Adult male and female Sprague-Dawley rats were compared in terms of the constitutive levels and inducibility of CYP1A1 and\\u000a CYP1A2 (CYP1A) in lung, kidney, and liver. CYP1A were induced by i.p. treatment with pyridine (75?mg\\/kg per day) or ?-naphthoflavone\\u000a (?NF; 25?mg\\/kg per day) for two consecutive days and analyzed catalytically (via O-dealkylation of resorufin ethers), at the\\u000a protein level (by

Michael M. Iba; Jacqueline Fung; Paul E. Thomas

1999-01-01

77

d-alpha-tocopherol inhibits collagen alpha 1(I) gene expression in cultured human fibroblasts. Modulation of constitutive collagen gene expression by lipid peroxidation.  

PubMed Central

Ascorbic acid stimulates collagen gene transcription in cultured fibroblasts, and this effect is mediated through the induction of lipid peroxidation by ascorbic acid. Quiescent cultured fibroblasts in the absence of ascorbic acid have a high constitutive level of collagen production, but the mechanisms of collagen gene regulation in this unstimulated state are not known. Because lipid peroxidation also occurs in normal cells, we wondered if lipid peroxidation plays a role in the regulation of basal collagen gene expression. Inhibition of lipid peroxidation in cultured human fibroblasts with d-alpha-tocopherol or methylene blue decreased the synthesis of collagen, the steady-state levels of procollagen alpha 1(I) mRNA and the transcription of the procollagen alpha 1(I) gene. This effect on collagen gene expression was selective and not associated with cellular toxicity. Thus, these experiments suggest a role for lipid peroxidation in the modulation of constitutive collagen gene expression. Images

Houglum, K; Brenner, D A; Chojkier, M

1991-01-01

78

Constitutive and Cytokine-Stimulated Expression of Eotaxin by Human Airway Smooth Muscle Cells  

Microsoft Academic Search

Airway eosinophilia is a prominent feature of asthma that is believed to be mediated in part through the expression of specific chemokines such as eotaxin, a potent eosinophil chemoattractant that is highly expressed by epithelial cells and inflammatory cells in asthmatic airways. Airway smooth mus- cle (ASM) has been identified as a potential source of cytokines and chemokines. The aim

OMAR GHAFFAR; QUTAYBA HAMID; PAOLO M. RENZI; ZOULFIA ALLAKHVERDI; SOPHIE MOLET; JAMES C. HOGG; STEPHANIE A. SHORE; ANDREW D. LUSTER; BOUCHAIB LAMKHIOUED

1999-01-01

79

International Constitutional Law (ICL)  

NSDL National Science Digital Library

Hosted by the University of Wuerzburg (Germany), International Constitutional Law (ICL) provides English texts of constitutional documents and links to background information on over seventy countries. Documents are cross-referenced for comparison of constitutional provisions. Also featured are links to Constitutional Court sites, a Model Constitutional Code, a section on German Case Law, a comprehensive list of international organizations, and a strong collection of links to constitutional and international law and constitution sites. The material available at ICL is widely applicable to fields such as political science, international relations, or government, and could be very useful for research projects in both secondary and university classrooms.

1997-01-01

80

[Establishment of mammalian cell lines for constitutive expression of influenza virus matrix protein 2].  

PubMed

To establish a mammalian cell line for stable expression of the matrix protein 2 (M2) of influenza virus type A. M2 gene was amplified by PCR from the influenza virus strain A/PR/8/34. The PCR product was cloned into eukaryotic expression vector pcDNA5/FRT. After identification with restriction enzyme digestion, the plasmid was co-transfected with plasmid pOG44 which expressed Flp in Flp-In-CHO cells. The target gene was integrated into chromosome of CHO cells by homologous recombination in vivo. Recombinant CHO-M2 cell lines were selected for hygromycin B resistance. A total of 15 recombinant cell strains with high expression of M2 protein were screened by hygromycin, and the expression of M2 protein was determined by IFA and Western blot. After subculturing for 10 passages, the presence of M2 gene in the CHO-M2 cells was confirmed by PCR, and the expression of M2 protein were proved by IFA and Western blot. We successfully constructed a mammalian cell line which stably expressed M2 protein of influenza virus type A. The cell line will be useful for studies on function of M2 protein and provide tools for novel influenza virus vaccine development. PMID:23547373

Chen, Ai-Jun; Guo, Jian-Qiang; Yao, Li-Hong; Yin, Ji-Yong; Zhang, Zhi-Qing

2013-01-01

81

High-Level Expression, Purification and Characterization of a Constitutively Active Thromboxane A2 Receptor Polymorphic Variant  

PubMed Central

G protein-coupled receptors (GPCRs) exhibit some level of basal signaling even in the absence of a bound agonist. This basal or constitutive signaling can have important pathophysiological roles. In the past few years, a number of high resolution crystal structures of GPCRs have been reported, including two crystal structures of constitutively active mutants (CAM) of the dim-light receptor, rhodopsin. The structural characterizations of CAMs are impeded by the lack of proper expression systems. The thromboxane A2 receptor (TP) is a GPCR that mediates vasoconstriction and promotes thrombosis in response to the binding of thromboxane. Here, we report on the expression and purification of a genetic variant and CAM in TP, namely A160T, using tetracycline-inducible HEK293S-TetR and HEK293S (GnTIŻ)-TetR cell lines. Expression of the TP and the A160T genes in these mammalian cell lines resulted in a 4-fold increase in expression to a level of 15.8 ±0.3 pmol of receptor/mg of membrane protein. The receptors expressed in the HEK293S (GnTI-)-TetR cell line showed homogeneous glycosylation. The functional yield of the receptors using a single step affinity purification was 45 µg/106 cells. Temperature- dependent secondary structure changes of the purified TP and A160T receptors were characterized using circular dichroism (CD) spectropolarimetry. The CD spectra shows that the loss of activity or thermal sensitivity that was previously observed for the A160T mutant, is not owing to large unfolding of the protein but rather to a more subtle effect. This is the first study to report on the successful high-level expression, purification, and biophysical characterization of a naturally occurring, diffusible ligand activated GPCR CAM.

Xu, Bing; Chakraborty, Raja; Eilers, Markus; Dakshinamurti, Shyamala; O'Neil, Joe D.; Smith, Steven O.; Bhullar, Rajinder P.; Chelikani, Prashen

2013-01-01

82

Decreased accumulation of glutelin types in rice grains constitutively expressing a sunflower seed albumin gene  

Microsoft Academic Search

Previous studies have shown differential accumulation of sulfur rich glutelins and sulfur poor prolamins in transgenic rice seeds expressing a sunflower seed albumin gene [Hagan, N.D., Upadhyaya, N., Tabe, L.M., Higgins, T.J., 2003. The redistribution of protein sulfur in transgenic rice expressing a gene for a foreign, sulfur-rich protein. Plant J 34, 1–11]. Here, we show, by two-dimensional electrophoresis, differential

Nazrul Islam; Narayana M. Upadhyaya; Peter. M. Campbell; Ray Akhurst; Nick Hagan; Thomas J. V. Higgins

2005-01-01

83

Suppressed NFAT-dependent VEGFR1 expression and constitutive VEGFR2 signaling in infantile hemangioma  

Microsoft Academic Search

Infantile hemangiomas are localized and rapidly growing regions of disorganized angiogenesis. We show that expression of vascular endothelial growth factor receptor-1 (VEGFR1) in hemangioma endothelial cells (hemECs) and hemangioma tissue is markedly reduced compared to controls. Low VEGFR1 expression in hemECs results in VEGF-dependent activation of VEGFR2 and downstream signaling pathways. In hemECs, transcription of the gene encoding VEGFR1 (FLT1)

Masatoshi Jinnin; Damian Medici; Lucy Park; Nisha Limaye; Yanqiu Liu; Elisa Boscolo; Joyce Bischoff; Miikka Vikkula; Eileen Boye; Bjorn R Olsen

2008-01-01

84

Constitutive Expression and Optimization of Nutrients for Streptokinase Production by Pichia pastoris Using Statistical Methods  

Microsoft Academic Search

The Pichia pastoris clone producing streptokinase (SK) was optimized for its nutritional requirements to improve intracellular expression using\\u000a statistical experimental designs and response surface methodology. The skc gene was ligated downstream of the native glyceraldehyde 3-phosphate dehydrogenase promoter and cloned in P. pastoris. Toxicity to the host was not observed by SK expression using YPD medium. The transformant producing SK

Ravi Nagaraj Vellanki; Ravichandra Potumarthi; Lakshmi Narasu Mangamoori

2009-01-01

85

Constitutive HIF-1? Expression Blunts the Beneficial Effects of Cardiosphere-Derived Cell Therapy in the Heart by Altering Paracrine Factor Balance  

Microsoft Academic Search

Hypoxia-inducible factor-1alpha (HIF-1?) expression promotes angiogenesis and can influence stem cell engraftment. We investigated\\u000a the effect of stable over-expression of constitutively active HIF-1? on cardiosphere-derived cell (CDC) engraftment and left\\u000a ventricular function. CDCs were transduced with a lentivirus expressing a constitutively active mutant of human HIF-1? (LVHIF-1?).\\u000a Two million male rat CDCs were injected into the infarct following ligation of

Michael Bonios; Connie Yachan Chang; John Terrovitis; Aurelio Pinheiro; Andreas Barth; Peihong Dong; Miguel Santaularia; D. Brian Foster; Venu Raman; Theodore P. Abraham; Maria Roselle Abraham

2011-01-01

86

On the Origins of Background Emotions: From Affect Synchrony to Symbolic Expression  

Microsoft Academic Search

Guided by Damasio's (2003) formulations on background emotions, this study examined the contour of infant affect during interactions with mother and father in relation to the emergence of symbolic expression. One hundred parents and infants were observed in face-to-face interactions and in play sessions at the toddler stage. Parent's and infants' affective states were coded in 1-s frames, and synchrony

Ruth Feldman

2007-01-01

87

Constitutive JunB expression, associated with the JAK2 V617F mutation, stimulates proliferation of the erythroid lineage.  

PubMed

The JAK2 V617F mutation, present in the majority of polycythemia vera (PV) patients, causes constitutive activation of JAK2 and seems to be responsible for the PV phenotype. However, the transcriptional changes triggered by the mutation have not yet been totally characterized. In this study, we performed a large-scale gene expression study using serial analysis of gene expression in bone marrow cells of a newly diagnosed PV patient harboring the JAK2 V617F mutation and in normal bone marrow cells of healthy donors. JUNB was one of the genes upregulated in PV, and we confirmed, by quantitative real-time PCR, an overexpression of JUNB in hematopoietic cells of other JAK2 V617F PV patients. Using Ba/F3-EPOR cell lines and primary human erythroblast cultures, we found that JUNB was transcriptionally induced after erythropoietin addition and that JAK2 V617F constitutively induced JunB protein expression. Furthermore, JUNB knockdown reduced not only the growth of Ba/F3 cells by inducing apoptosis, but also the clonogenic and proliferative potential of human erythroid progenitors. These results establish a role for JunB in normal erythropoiesis and indicate that JunB may play a major role in the development of JAK2 V617F myeloproliferative disorders. PMID:18843287

da Costa Reis Monte-Mór, B; Plo, I; da Cunha, A F; Costa, G G L; de Albuquerque, D M; Jedidi, A; Villeval, J-L; Badaoui, S; Lorand-Metze, I; Pagnano, K B B; Saad, S T O; Vainchenker, W; Costa, F F

2008-10-09

88

Rhizoremediation of Trichloroethylene by a Recombinant, Root-Colonizing Pseudomonas fluorescens Strain Expressing Toluene ortho-Monooxygenase Constitutively  

PubMed Central

Trichloroethylene (TCE) was removed from soils by using a wheat rhizosphere established by coating seeds with a recombinant, TCE-degrading Pseudomonas fluorescens strain that expresses the tomA+ (toluene o-monooxygenase) genes from Burkholderia cepacia PR123(TOM23C). A transposon integration vector was used to insert tomA+ into the chromosome of P. fluorescens 2-79, producing a stable strain that expressed constitutively the monooxygenase at a level of 1.1 nmol/min · mg of protein (initial TCE concentration, 10 ?M, assuming that all of the TCE was in the liquid) for more than 280 cell generations (36 days). We also constructed a salicylate-inducible P. fluorescens strain that degraded TCE at an initial rate of 2.6 nmol/min · mg of protein in the presence of 10 ?M TCE [cf. B. cepacia G4 PR123(TOM23C), which degraded TCE at an initial rate of 2.5 nmol/min · mg of protein]. A constitutive strain, P. fluorescens 2-79TOM, grew (maximum specific growth rate, 0.78 h?1) and colonized wheat (3 × 106 CFU/cm of root) as well as wild-type P. fluorescens 2-79 (maximum specific growth rate, 0.77 h?1; level of colonization, 4 × 106 CFU/cm of root). Rhizoremediation of TCE was demonstrated by using microcosms containing the constitutive monooxygenase-expressing microorganism, soil, and wheat. These closed microcosms degraded an average of 63% of the initial TCE in 4 days (20.6 nmol of TCE/day · plant), compared to the 9% of the initial TCE removed by negative controls consisting of microcosms containing wild-type P. fluorescens 2-79-inoculated wheat, uninoculated wheat, or sterile soil.

Yee, Dennis C.; Maynard, Jennifer A.; Wood, Thomas K.

1998-01-01

89

Inducible and constitutive expression of pMOL28-encoded nickel resistance in Alcaligenes eutrophus N9A.  

PubMed Central

The nickel and cobalt resistance plasmid pMOL28 was transferred by conjugation from its natural host Alcaligenes eutrophus CH34 to the susceptible A. eutrophus N9A. Strain N9A and its pMOL28-containing transconjugant M220 were studied in detail. At a concentration of 3.0 mM NiCl2, the wild-type N9A did not grow, while M220 started to grow at its maximum exponential growth rate after a lag of 12 to 24 h. When grown in the presence of subinhibitory concentrations (0.5 mM) of nickel salt, M220 grew actively at 3 mM NiCl2 without a lag, indicating that nickel resistance is an inducible property. Expression of nickel resistance required active growth in the presence of nickel salts at a concentration higher than 0.05 mM. Two mutants of M220 were isolated which expressed nickel resistance constitutively. When the plasmids, pMOL28.1 and pMOL28.2, carried by the mutants were transferred to strains H16 and CH34, the transconjugants expressed constitutive nickel resistance. This indicates that the mutation is plasmid located. Both mutants expressed constitutive resistance to nickel and cobalt. Physiological studies revealed the following differences between strain N9A and its pMOL28.1-harboring mutant derivatives. (i) The uptake of 63NiCl2 occurred more rapidly in the susceptible strain and reached a 30- to 60-fold-higher amount that in the pMOL28.1-harboring mutant; (ii) in intact cells of the susceptible strain N9A, the cytoplasmic hydrogenase was inhibited by 1 to 5 nM NiCl2, whereas 10 mM Ni2+ was needed to inhibit the hydrogenase of mutant cells; (iii) the minimal concentration of nickel chloride for the derepressed synthesis of cytoplasmic hydrogenase was lower in strain N9A (1 to 3 microM) than in the constitutive mutant (8 to 10 microM).

Siddiqui, R A; Schlegel, H G; Meyer, M

1988-01-01

90

Distribution of constitutively expressed MEF-2A in adult rat and human nervous systems.  

PubMed

Myocyte enhancer factor 2A (MEF-2A) is a calcium-regulated transcription factor that promotes cell survival during nervous system development. To define and further characterize the distribution pattern of MEF-2A in the adult mammalian brain, we used a specific polyclonal antiserum against human MEF-2A to identify nuclear-localized MEF-2A protein in hippocampal and frontal cortical regions. Western blot and immunocytochemical analyses showed that MEF-2A was expressed not only in laminar structures but also in blood vessels of rat and human brains. MEF-2A was colocalized with doublecortin (DCX), a microtubule-associated protein expressed by migrating neuroblasts, in CA1 and CA2 boundaries of the hippocampus. MEF-2A was expressed heterogeneously in additional structures of the rat brain, including the striatum, thalamus, and cerebellum. Furthermore, we found a strong nuclear and diffuse MEF-2A labeling pattern in spinal cord cells of rat and human material. Finally, the neurovasculature of adult rats and humans not only showed a strong expression of MEF-2A but also labeled positive for hyperpolarization-activated, cyclic nucleotide-regulated (HCN) channels. This study further characterizes the distribution pattern of MEF-2A in the mammalian nervous system, demonstrates that MEF-2A colocalizes with DCX in selected neurons, and finds MEF-2A and HCN1 proteins in the neurovasculature network. PMID:16565967

Ruffle, Rebecca A; Mapley, Andrew C; Malik, Manmeet K; Labruzzo, Salvatore V; Chabla, Janet M; Jose, Riya; Hallas, Brian H; Yu, Han-Gang; Horowitz, Judith M; Torres, German

2006-06-15

91

Abnormal differentiation of epidermis in transgenic mice constitutively expressing cyclooxygenase-2 in skin  

PubMed Central

In prostanoid biosynthesis, the first two steps are catalyzed by cyclooxygenases (COX). In mice and humans, deregulated expression of COX-2, but not of COX-1, is characteristic of epithelial tumors, including squamous cell carcinomas of skin. To explore the function of COX-2 in epidermis, a keratin 5 promoter was used to direct COX-2 expression to the basal cells of interfollicular epidermis and the pilosebaceous appendage of transgenic mouse skin. COX-2 overexpression in the expected locations, resulting in increased prostaglandin levels in epidermis and plasma, correlated with a pronounced skin phenotype. Heterozygous transgenic mice exhibited a reduced hair follicle density. Moreover, postnatally hair follicle morphogenesis and thinning of interfollicular dorsal epidermis were delayed. Adult transgenics showed a body-site-dependent sparse coat of greasy hair, the latter caused by sebaceous gland hyperplasia and increased epicutaneous sebum levels. In tail skin, hyperplasia of scale epidermis reflecting an increased number of viable and cornified cell layers was observed. Hyperplasia was a result of a disturbed program of epidermal differentiation rather than an increased proliferation rate, as reflected by the strong suppression of keratin 10, involucrin, and loricrin expression in suprabasal cells. Further pathological signs were loss of cell polarity, mainly of basal keratinocytes, epidermal invaginations into the dermis, and formation of horn perls. Invaginating hyperplastic lobes were surrounded by CD31-positive vessels. These results demonstrate a causal relationship between transgenic COX-2 expression in basal keratinocytes and epidermal hyperplasia as well as dysplastic features at discrete body sites.

Neufang, Gitta; Furstenberger, Gerhard; Heidt, Markus; Marks, Friedrich; Muller-Decker, Karin

2001-01-01

92

Expression variation of the porcine ADRB2 has a complex genetic background.  

PubMed

Porcine adrenergic receptor beta 2 (ADRB2) gene exhibits differential allelic expression in skeletal muscle, and its genetic variation has been associated with muscle pH. Exploring the molecular-genetic background of expression variation for porcine ADRB2 will provide insight into the mechanisms driving its regulatory divergence and may also contribute to unraveling the genetic basis of muscle-related traits in pigs. In the present study, we therefore examined haplotype effects on the expression of porcine ADRB2 in four tissues: longissimus dorsi muscle, liver, subcutaneous fat, and spleen. The diversity and structure of haplotypes of the proximal gene region segregating in German commercial breeds were characterized. Seven haplotypes falling into three clades were identified. Two clades including five haplotypes most likely originated from introgression of Asian genetics during formation of modern breeds. Expression analyses revealed that the Asian-derived haplotypes increase expression of the porcine ADRB2 compared to the major, wild-type haplotype independently of tissue type. In addition, several tissue-specific differences in the expression of the Asian-derived haplotypes were found. Inspection of haplotype sequences showed that differentially expressed haplotypes exhibit polymorphisms in a polyguanine tract located in the core promoter region. These findings demonstrate that expression variation of the porcine ADRB2 has a complex genetic basis and suggest that the promoter polyguanine tract is causally involved. This study highlights the challenges of finding causal genetic variants underlying complex traits. PMID:23996144

Murani, Eduard; Ponsuksili, Siriluck; Reyer, Henry; Wittenburg, Dörte; Wimmers, Klaus

2013-08-31

93

Temporally regulated expression of a yeast invertase in potato tubers allows dissection of the complex metabolic phenotype obtained following its constitutive expression.  

PubMed

The constitutive cytosolic expression of a yeast ( Saccharomyces cerevisiae ) invertase within potato ( Solanum tuberosum ) tubers has previously been documented to produce a dramatic metabolic phenotype in which glycolysis, respiration and amino acid synthesis are markedly enhanced at the cost of starch synthesis. These transgenic lines were further characterised by a massive cycle of sucrose degradation and resynthesis via sucrose-phosphate synthase. We have recently developed a B33 patatin driven alc gene construct allowing tight chemical control of gene expression following supply of acetaldehyde with minimal pleiotropic effects of the inducing agent on metabolism. This construct was used for chemical induction of the yeast invertase gene after 10-weeks growth to dissect the complex metabolic phenotype obtained after constitute expression. Inducible expression led to increased invertase activity within 24 h in well-defined areas within growing tubers. Although the sucrose levels were reduced, there was no effect on the levels of starch whilst levels of many amino acids decreased. Labelling experiments revealed that these lines exhibited increased rates of sucrose cycling, whereas rates of glycolysis and of starch synthesis were not substantially changed. From these results we conclude that sucrose cycling is stimulated in response to a short-term increase in the rate of sucrose mobilisation, providing evidence for a role of sucrose cycling as a buffering capacity that regulates the net rate of sucrose usage. In contrast, the dramatic increase in hexose-phosphate levels and the switch from starch synthesis to respiration seen on the constitutive expression of the invertase was not observed in the inducible lines, suggesting that this is the result of cumulative pleiotropic effects that occurred when the transgene was expressed throughout development. PMID:15604730

Junker, Björn H; Wuttke, René; Tiessen, Axel; Geigenberger, Peter; Sonnewald, Uwe; Willmitzer, Lothar; Fernie, Alisdair R

2004-09-01

94

Transgenic Mice Expressing Constitutively Active Akt in Oral Epithelium Validate Klf4 as a Potential Biomarker of Head and Neck Squamous Cell Carcinoma  

PubMed Central

Background Head and neck squamous cell carcinoma (HNSCC) is a common human neoplasia, of poor prognosis and survival, which frequently displays Akt overactivation. Previously, we reported that mice expressing high levels of constitutively Akt activity (myrAkt) in oral epithelia develop lesions and tumors in the oral cavity. Materials and Methods Functional genomics of primary keratinocytes from different transgenic mouse lines and immunostaining of mouse and human samples were performed in order to identify and validate putative biomarkers of oral cancer progression. Results The expression of KLF4 was found to be increased only in tumor prone samples from mice bearing overactivation of Akt. Such increased expression was confirmed in oral dysplasias and tumors arising in those mice. Tissue microarray analysis of human samples confirmed the association between active Akt and increased KLF4 expression. Conclusion These data support the notion that KLF4 is potentially a reliable marker of HNSCC, and that myrAkt transgenic mice are valuable tools for preclinical research of HNSCC.

Moral, Marta; Segrelles, Carmen; Martinez-Cruz, Ana Belen; Lorz, Corina; Santos, Mirentxu; Garcia-Escudero, Ramon; Lu, Jerry; Buitrago, Agueda; Costa, Clotilde; Saiz, Cristina; Ariza, Jose M.; Duenas, Marta; Rodriguez-Peralto, Jose L; Martinez-Tello, Francisco J; Rodriguez-Pinilla, Maria; Sanchez-Cespedes, Montserrat; DiGiovanni, John; Paramio, Jesus M.

2010-01-01

95

Constitutive TL1A Expression under Colitogenic Conditions Modulates the Severity and Location of Gut Mucosal Inflammation and Induces Fibrostenosis  

PubMed Central

Intestinal fibrostenosis is a hallmark of severe Crohn's disease and can lead to multiple surgeries. Patients with certain TNFSF15 variants overexpress TL1A. The aim of this study was to determine the effect of TL1A overexpression on intestinal inflammation and the development of fibrostenosis. We assessed the in vivo consequences of constitutive TL1A expression on gut mucosal inflammation and fibrostenosis using two murine models of chronic colitis. In the dextran sodium sulfate (DSS) and adoptive T-cell transfer models, there was proximal migration of colonic inflammation, worsened patchy intestinal inflammation, and long gross intestinal strictures in Tl1a transgenic compared to wild-type littermates. In the DSS model, myeloid- and T-cell–expressing Tl1a transgenic mice had increased T-cell activation markers and interleukin-17 expression compared to wild-type mice. In the T-cell transfer model, Rag1?/? mice receiving Tl1a transgenic T cells had increased interferon-? expression but reduced T-helper 17 cells and IL-17 production. Narrowed ureters with hydronephrosis were found only in the Tl1a transgenic mice in all chronic colitis models. In human translational studies, Crohn's disease patients with higher peripheral TL1A expression also exhibited intestinal fibrostenosis and worsened ileocecal inflammation with relative sparing of rectosigmoid inflammation. These data show that TL1A is an important cytokine that not only modulates the location and severity of mucosal inflammation, but also induces fibrostenosis.

Barrett, Robert; Zhang, Xiaolan; Koon, Hon Wai; Vu, Michelle; Chang, Jyh-Yau; Yeager, Nicole; Nguyen, Mary Ann; Michelsen, Kathrin S.; Berel, Dror; Pothoulakis, Charalabos; Targan, Stephan R.; Shih, David Q.

2012-01-01

96

Higher constitutive IL15R? expression and lower IL-15 response threshold in coeliac disease patients  

PubMed Central

The IL-15 triggering effect of gliadin is not exclusive to coeliac disease (CD) patients, whereas the secondary response is CD specific. We have studied the expression of the IL-15 receptor, and the IL-15 response upon stimulation, in non-CD and CD patients, and the possible existence of a lower immunological threshold in the latter. Forty-two CD patients (20 on a gluten-containing diet, GCD, and 22 on gluten-free diet, GFD) and 24 non-CD healthy individuals were studied. IL15R? mRNA expression, and tissue characterization, were assayed in the duodenum. Biopsies from six CD patients on GFD and 10 non-CD individuals were studied in vitro using organ culture in basal conditions, as well as after IL-15 stimulation discarding basal IL-15 production. Secretion of immune mediators was measured in the culture supernatants. IL15R? mRNA expression was increased in CD patients, as compared with non-CD controls (on GFD P = 0·0334, on GCD P = 0·0062, respectively), and confirmed also by immunofluorescence. No differences were found between CD patients on GFD and on GCD. After in vitro IL-15 stimulation, IL15R? expression was only triggered in non-CD controls (P = 0·0313), though it remained increased in CD patients. Moreover, IL-15 induced a more intense immunological response in CD patients after triggering the production of both nitrites and IFN? (P = 0·0313, P = 0·0313, respectively). Gliadin-induced IL15 has a lower response threshold in CD patients, leading to the production of other immune mediators and the development of the intestinal lesion, and thus magnifying its effects within the CD intestine.

Bernardo, D; Garrote, J A; Allegretti, Y; Leon, A; Gomez, E; Bermejo-Martin, J F; Calvo, C; Riestra, S; Fernandez-Salazar, L; Blanco-Quiros, A; Chirdo, F; Arranz, E

2008-01-01

97

Constitutive and Regulated Expression of Telomerase Reverse Transcriptase (hTERT) in Human Lymphocytes  

Microsoft Academic Search

Human telomerase consists of two essential components, telomerase RNA template (hTER) and telomerase reverse transcriptase (hTERT), and functions to synthesize telomere repeats that serve to protect the integrity of chromosomes and to prolong the replicative life span of cells. Telomerase activity is expressed selectively in germ-line and malignant tumor cells but not in most normal human somatic cells. As a

Kebin Liu; Michele M. Schoonmaker; Bruce L. Levine; Carl H. June; Richard J. Hodes; Nan-Ping Weng

1999-01-01

98

Constitutive expression of cytotoxic proteases and down-regulation of protease inhibitors in LGL leukemia.  

PubMed

Large granular lymphocyte (LGL) leukemia is a lymphoproliferative disorder often associated with rheumatoid arthritis. The etiology of LGL leukemia is not known. In order to better understand the pathogenesis of LGL leukemia, we analyzed differential gene expression using microarray technology. We found that approximately 80 genes were up-regulated and 12 genes were down-regulated when compared to normal peripheral blood mononuclear cells (PBMC). In the present study, we were interested in a group of genes involved in cytotoxic function. The up-regulated genes involved in cytotoxic function were serine proteinases (granzymes A, B, H and K) cysteine proteinases [cathepsin C, cathepsin W (lymphopain)], calpain small subunit and caspase-8. In addition, a pore-forming protein perforin, was also up-regulated. Northern blot analysis and RNase protection assays (RPA) confirmed that these genes were over-expressed in the majority of samples from LGL leukemia patients. Of interest, proteolytic inhibitors such as cystatin C, A, alpha-1 antitrypsin and metalloproteinase inhibitors were down-regulated in leukemic LGL when compared to normal peripheral blood mononuclear cells. Importantly, the pattern of gene expression in leukemic LGL resembles that seen in activated cytotoxic T cells (CTL). PMID:12469182

Kothapalli, Ravi; Bailey, Ratna D; Kusmartseva, Irina; Mane, Shrikant; Epling-Burnette, P K; Loughran, Thomas P

2003-01-01

99

Constitutive expression of Atlantic salmon Mx1 protein in CHSE-214 cells confers resistance to infectious salmon anaemia virus.  

PubMed

Infectious salmon anaemia (ISA) is a highly fatal viral disease affecting marine-farmed Atlantic salmon which is caused by ISA virus (ISAV), a fish orthomyxovirus that has recently been assigned to the new genus Isavirus within the family Orthomyxoviridae. Mx proteins are among the interferon (IFN)-induced proteins responsible for the development of an antiviral state in vertebrate cells. We used real-time reverse transcription-polymerase chain reaction (RT-PCR) and Chinook salmon embryo (CHSE-214) cells constitutively expressing Atlantic salmon Mx1 protein (ASMx1) to examine the antiviral properties of ASMx1 against two ISAV strains, NBISA01 and HKS-36, having phenotypically different growth properties (cytopathic vs non-cytopathic) in the CHSE-214 cell line. We present evidence that ISAV is sensitive to ASMx1. CHSE-214 cells constitutively expressing ASMx1 showed increased resistance to infection with the cytopathic ISAV strain NBISA01, manifested as delayed development of cytopathic effects (CPE) and significant reduction in the severity of CPE, as well as a 10-fold reduction in virus yield. However, by real-time RT-PCR we observed no significant difference in the mean threshold cycle (Ct) values of ISAV RNA levels, suggesting that the ASMx1 activity on ISAV occurs at the post-transcription steps of virus replication, possibly in the cytoplasm. PMID:16124877

Kibenge, Molly J T; Munir, Khalid; Kibenge, Frederick S B

2005-08-26

100

Constitutive expression of Atlantic salmon Mx1 protein in CHSE-214 cells confers resistance to Infectious Salmon Anaemia virus  

PubMed Central

Infectious salmon anaemia (ISA) is a highly fatal viral disease affecting marine-farmed Atlantic salmon which is caused by ISA virus (ISAV), a fish orthomyxovirus that has recently been assigned to the new genus Isavirus within the family Orthomyxoviridae. Mx proteins are among the interferon (IFN)-induced proteins responsible for the development of an antiviral state in vertebrate cells. We used real-time reverse transcription-polymerase chain reaction (RT-PCR) and Chinook salmon embryo (CHSE-214) cells constitutively expressing Atlantic salmon Mx1 protein (ASMx1) to examine the antiviral properties of ASMx1 against two ISAV strains, NBISA01 and HKS-36, having phenotypically different growth properties (cytopathic vs non-cytopathic) in the CHSE-214 cell line. We present evidence that ISAV is sensitive to ASMx1. CHSE-214 cells constitutively expressing ASMx1 showed increased resistance to infection with the cytopathic ISAV strain NBISA01, manifested as delayed development of cytopathic effects (CPE) and significant reduction in the severity of CPE, as well as a 10-fold reduction in virus yield. However, by real-time RT-PCR we observed no significant difference in the mean threshold cycle (Ct) values of ISAV RNA levels, suggesting that the ASMx1 activity on ISAV occurs at the post-transcription steps of virus replication, possibly in the cytoplasm.

Kibenge, Molly JT; Munir, Khalid; Kibenge, Frederick SB

2005-01-01

101

Constitutive expression of Yes-associated protein (Yap) in adult skeletal muscle fibres induces muscle atrophy and myopathy.  

PubMed

The aim of this study was to investigate the function of the Hippo pathway member Yes-associated protein (Yap, gene name Yap1) in skeletal muscle fibres in vivo. Specifically we bred an inducible, skeletal muscle fibre-specific knock-in mouse model (MCK-tTA-hYAP1 S127A) to test whether the over expression of constitutively active Yap (hYAP1 S127A) is sufficient to drive muscle hypertrophy or stimulate changes in fibre type composition. Unexpectedly, after 5-7 weeks of constitutive hYAP1 S127A over expression, mice suddenly and rapidly lost 20-25% body weight and suffered from gait impairments and kyphosis. Skeletal muscles atrophied by 34-40% and the muscle fibre cross sectional area decreased by ?40% when compared to control mice. Histological analysis revealed evidence of skeletal muscle degeneration and regeneration, necrotic fibres and a NADH-TR staining resembling centronuclear myopathy. In agreement with the histology, mRNA expression of markers of regenerative myogenesis (embryonic myosin heavy chain, Myf5, myogenin, Pax7) and muscle protein degradation (atrogin-1, MuRF1) were significantly elevated in muscles from transgenic mice versus control. No significant changes in fibre type composition were detected using ATPase staining. The phenotype was largely reversible, as a cessation of hYAP1 S127A expression rescued body and muscle weight, restored muscle morphology and prevented further pathological progression. To conclude, high Yap activity in muscle fibres does not induce fibre hypertrophy nor fibre type changes but instead results in a reversible atrophy and deterioration. PMID:23544078

Judson, Robert N; Gray, Stuart R; Walker, Claire; Carroll, Andrew M; Itzstein, Cecile; Lionikas, Arimantas; Zammit, Peter S; De Bari, Cosimo; Wackerhage, Henning

2013-03-27

102

The Constitution Outside the Constitution  

Microsoft Academic Search

Countries lacking a single canonical text define the “constitution” to include all laws that perform the constitutive functions of creating governmental institutions and conferring rights on individuals. The British Constitution, for example, includes a variety of constitutive statutes, such as the Magna Carta and the Parliament Acts. This Article proposes a thought experiment: what if we defined the U.S. Constitution

Ernest A. Young

2007-01-01

103

Constitutively active Akt1 expression in mouse pancreas requires S6 kinase 1 for insulinoma formation  

PubMed Central

Factors that promote pancreatic ? cell growth and function are potential therapeutic targets for diabetes mellitus. In mice, genetic experiments suggest that signaling cascades initiated by insulin and IGFs positively regulate ? cell mass and insulin secretion. Akt and S6 kinase (S6K) family members are activated as part of these signaling cascades, but how the interplay between these proteins controls ? cell growth and function has not been determined. Here, we found that although transgenic mice overexpressing the constitutively active form of Akt1 under the rat insulin promoter (RIP-MyrAkt1 mice) had enlarged ? cells and high plasma insulin levels, leading to improved glucose tolerance, a substantial proportion of the mice developed insulinomas later in life, which caused decreased viability. This oncogenic transformation tightly correlated with nuclear exclusion of the tumor suppressor PTEN. To address the role of the mammalian target of rapamycin (mTOR) substrate S6K1 in the MyrAkt1-mediated phenotype, we crossed RIP-MyrAkt1 and S6K1-deficient mice. The resulting mice displayed reduced insulinemia and glycemia compared with RIP-MyrAkt1 mice due to a combined effect of improved insulin secretion and insulin sensitivity. Importantly, although the increase in ? cell size in RIP-MyrAkt1 mice was not affected by S6K1 deficiency, the hyperplastic transformation required S6K1. Our results therefore identify S6K1 as a critical element for MyrAkt1-induced tumor formation and suggest that it may represent a useful target for anticancer therapy downstream of mTOR.

Alliouachene, Samira; Tuttle, Robyn L.; Boumard, Stephanie; Lapointe, Thomas; Berissi, Sophie; Germain, Stephane; Jaubert, Francis; Tosh, David; Birnbaum, Morris J.; Pende, Mario

2008-01-01

104

Constitutive Expression of MAP Kinase Phosphatase-1 Confers Multi-drug Resistance in Human Glioblastoma Cells  

PubMed Central

Purpose Current treatment of glioblastoma after surgery consists of a combination of fractionated radiotherapy and temozolomide. However, it is difficult to completely remove glioblastoma because it has uncertain boundaries with surrounding tissues. Moreover, combination therapy is not always successful because glioblastoma has diverse resistances. To overcome these limitations, we examined the combined effects of chemotherapy and knockdown of mitogen-activated protein kinase phosphatase-1 (MKP-1). Materials and Methods We used ten different anti-cancer drugs (cisplatin, cyclophosphoamide, doxorubicin, epirubicin, etoposide, 5-fluorouracil, gemcitabine, irinotecan, mitomycin C, and vincristine) to treat glioblastoma multiforme (GBM) cells. Knockdown of MKP-1 was performed using siRNA and lipofectamine. The basal level of MKP-1 in GBM was analyzed based on cDNA microarray data obtained from the Gene Expression Omnibus (GEO) databases. Results Anti-cancer drug-induced cell death was significantly enhanced by knockdown of MKP-1, and this effect was most prominent in cells treated with irinotecan and etoposide. Treatment with these two drugs led to significantly increased phosphorylation of c-Jun N-terminal kinase (JNK) in a time-dependent manner, while pharmacological inhibition of JNK partially inhibited drug-induced cell death. Knockdown of MKP-1 also enhanced drug-induced phosphorylation of JNK. Conclusion Increased MKP-1 expression levels could be the cause of the high resistance to conventional chemotherapeutics in human GBM. Therefore, MKP-1 is an attractive target for overcoming drug resistance in this highly refractory malignancy.

Yu, Hana; Park, Junseong; Lee, Jungsul; Choi, Kyungsun

2012-01-01

105

Constitutive expression of interleukin-1alpha messenger ribonucleic acid in rat Sertoli cells is dependent upon interaction with germ cells.  

PubMed

Interleukin-1 (IL-1), a proinflammatory cytokine originally isolated as a product of activated mononuclear phagocytes, consists of two distinct agonist proteins, IL-1alpha and IL-1beta, of which IL-1beta is the major inducible IL-1 protein produced by macrophages. We show here that mRNA of IL-1alpha, but not IL-1beta, is constitutively expressed by the intact rat testis and localize the transcript to Sertoli cells as confirmed by a novel squash technique. The expression is developmentally regulated and appears only after postnatal day 20 in the rat testis, corresponding to onset of puberty. IL-1alpha mRNA shows a stage-dependent expression pattern during the cycle of the seminiferous epithelium. It is low or absent in stage VII, but present in all other stages of the cycle. The same stage-dependent distribution was also observed at the protein level when bioactive IL-1 was measured in extracts of accurately defined one millimeter segments of seminiferous tubules. No IL-1alpha mRNA was detected in adult rat testes after germ cell depletion by fetal irradiation or cytostatic drug treatment. Because stage VII is the only segment of the seminiferous tubules lacking DNA replication, we propose that IL-1alpha is involved in this event during mitosis and meiosis of spermatogenesis and that its expression is dependent upon interactions between Sertoli cells and germ cells. PMID:10433236

Jonsson, C K; Zetterström, R H; Holst, M; Parvinen, M; Söder, O

1999-08-01

106

Constitutive and retinoic acid-inducible expression of cytomegalovirus immediate-early genes in human teratocarcinoma cells.  

PubMed

Human teratocarcinoma stem cells are nonpermissive for human cytomegalovirus (HCMV) but become permissive after being induced to differentiate by treatment with retinoic acid. We show that in uninduced teratocarcinoma stem cells, and also in transformed human 293 cells expressing adenovirus E1a gene products, the HCMV immediate-early (IE) 68,000-molecular-weight polypeptide (68K polypeptide) was not expressed, and consequently input viral genomes were not replicated. However, after differentiation of the teratocarcinoma cells, synthesis of the HCMV IE 68K polypeptide was induced, and viral DNA replication occurred. In contrast to our observations for HCMV, simian cytomegalovirus (SCMV) displayed constitutive expression of its analogous IE 94K polypeptide, and the input SCMV genomes were replicated in both uninduced stem cells and 293 cells. Since little, if any, HCMV IE RNA was detectable in human teratocarcinoma or 293 cells after infection under IE conditions, we suggest that a direct transcriptional block to permissivity occurs in these cells. The presence of tandemly repeated sequences which bind nuclear factor I protein in the promoter for the SCMV IE 94K polypeptide gene but not in the promoter for the HCMV IE 68K polypeptide gene may allow the expression of the simian but not of the human IE gene product in transformed cells. PMID:3009858

LaFemina, R; Hayward, G S

1986-05-01

107

Identification of a constitutively active mutant of JAK3 by retroviral expression screening.  

PubMed

To identify transforming genes in acute myeloid leukemia (AML) we here constructed a retroviral cDNA expression library from an AML patient, and then used this library to infect a mouse cell line 32Dcl3-mCAT. cDNA inserts of the cell clones which proliferated in the presence of granulocyte colony-stimulating factor were derived from JAK3 encoding a JAK3 mutant with a valine-to-alanine substitution at codon 674 and two additional amino acid substitutions. The transforming activity of JAK3(V674A) was confirmed by its introduction into 32Dcl3-mCAT. Sequencing of the original JAK3 cDNA derived from the patient, however, failed to detect the V674A mutation. PMID:16790275

Choi, Young Lim; Kaneda, Ruri; Wada, Tomoaki; Fujiwara, Shin-Ichiro; Soda, Manabu; Watanabe, Hideki; Kurashina, Kentaro; Hatanaka, Hisashi; Enomoto, Munehiro; Takada, Shuji; Yamashita, Yoshihiro; Mano, Hiroyuki

2006-06-21

108

Plenary Perspective: The complexity of constitutive and inducible gene expression in mononuclear phagocytes  

PubMed Central

Monocytes and macrophages differentiate from progenitor cells under the influence of colony-stimulating factors. Genome-scale data have enabled the identification of the set of genes that distinguishes macrophages from other cell types and the ways in which thousands of genes are regulated in response to pathogen challenge. Although there has been a focus on a small subset of lineage-enriched transcription factors, such as PU.1, more than one-half of the transcription factors in the genome can be expressed in macrophage lineage cells under some state of activation, and they interact in a complex network. The network architecture is conserved across species, but many of the target genes evolve rapidly and differ between mouse and human. The data and publication deluge related to macrophage biology require the development of new analytical tools and ways of presenting information in an accessible form. The website www.macrophages.com is a community website that partly fills this niche.

Hume, David A.

2012-01-01

109

The Dioxin Receptor Regulates the Constitutive Expression of the Vav3 Proto-Oncogene and Modulates Cell Shape and Adhesion  

PubMed Central

The dioxin receptor (AhR) modulates cell plasticity and migration, although the signaling involved remains unknown. Here, we report a mechanism that integrates AhR into these cytoskeleton-related functions. Immortalized and mouse embryonic fibroblasts lacking AhR (AhR?/?) had increased cell area due to spread cytoplasms that reverted to wild-type morphology upon AhR re-expression. The AhR-null phenotype included increased F-actin stress fibers, depolarized focal adhesions, and enhanced spreading and adhesion. The cytoskeleton alterations of AhR?/? cells were due to down-regulation of constitutive Vav3 expression, a guanosine diphosphate/guanosine triphosphate exchange factor for Rho/Rac GTPases and a novel transcriptional target of AhR. AhR was recruited to the vav3 promoter and maintained constitutive mRNA expression in a ligand-independent manner. Consistently, AhR?/? fibroblasts had reduced Rac1 activity and increased activation of the RhoA/Rho kinase (Rock) pathway. Pharmacological inhibition of Rac1 shifted AhR+/+ fibroblasts to the null phenotype, whereas Rock inhibition changed AhR-null cells to the AhR+/+ morphology. Knockdown of vav3 transcripts by small interfering RNA induced cytoskeleton defects and changes in adhesion and spreading mimicking those of AhR-null cells. Moreover, vav3?/? MEFs, as AhR?/? mouse embryonic fibroblasts, had increased cell area and enhanced stress fibers. By modulating Vav3-dependent signaling, AhR could regulate cell shape, adhesion, and migration under physiological conditions and, perhaps, in certain pathological states.

Carvajal-Gonzalez, Jose M.; Mulero-Navarro, Sonia; Roman, Angel Carlos; Sauzeau, Vincent; Merino, Jaime M.; Bustelo, Xose R.

2009-01-01

110

Mouse neutrophils express the decoy type 2 interleukin-1 receptor (IL-1R2) constitutively and in acute inflammatory conditions.  

PubMed

The proinflammatory activities of IL-1 are tightly controlled at different levels. IL-1R2 acts as a decoy receptor and has been shown to regulate the biological effects of IL-1 in vitro and in vivo. However, little is known about its natural expression in the mouse in physiologic and pathologic conditions. In this study, we examined IL-1R2 mRNA and protein expression in isolated cells and tissues in response to different stimulatory conditions. Data obtained using ex vivo CD11b(+)Ly6G(+) peripheral blood cells and in vitro-differentiated CD11b(+)Ly6G(+) BMG indicated that neutrophils are the major source of constitutively expressed IL-1R2 in the mouse. The expression of IL-1R2 on BMG and ex vivo Ly6G(+) peripheral blood cells was highly up-regulated by HC. IL-1R2 pull-down experiments showed that mouse rIL-1? binds to BMG IL-1R2, whereas binding of IL-1Ra could not be detected. Furthermore, LPS treatment induced shedding of IL-1R2 from the neutrophil membrane in vitro and in vivo, executed mainly by ADAM17. Finally, in in vivo models of inflammation, including thioglycolate-induced acute peritonitis and acute lung injury, infiltrating Ly6G(+) neutrophils, expressed IL-1R2. Our data show that in the mouse, neutrophils mainly express the decoy receptor IL-1R2 under naďve and inflammatory conditions. These data suggest that neutrophils may contribute to the resolution of acute inflammation. PMID:23817563

Martin, Praxedis; Palmer, Gaby; Vigne, Solenne; Lamacchia, Céline; Rodriguez, Emiliana; Talabot-Ayer, Dominique; Rose-John, Stefan; Chalaris, Athena; Gabay, Cem

2013-07-01

111

Constitutive Expression of the ?4 Integrin Correlates with Tumorigenicity and Lymph Node Metastasis of the B16 Murine Melanoma1  

PubMed Central

The lymphatic system plays a critical role in melanoma metastasis, and yet, virtually no information exists regarding the cellular and molecular mechanisms that take place between melanoma cells and the lymphatic vasculature. Here, we generated B16-F1 melanoma cells that expressed high (B16?4+) and negligible (B16?4-) levels of ?4 integrin to determine how the expression of ?4 integrins affects tumor cell interactions with lymphatic endothelial cells in vitro and how it impacts lymphatic metastasis in vivo. We found a direct correlation between ?4 integrin expression on B16-F1 melanoma cells and their ability to form adhesive interactions with monolayers of lymphatic endothelial cells. Adhesion of B16-F1 melanoma cells to lymphatic endothelial cells was mediated by the melanoma cell ?4 integrin binding to its counterreceptor, vascular cell adhesion molecule 1 (VCAM-1), that was constitutively expressed on the lymphatic endothelial cells. VCAM-1 was also expressed on the tumor-associated lymphatic vessels of B16-F1 and B16?4+ tumors growing in the subcutaneous space of C57BL/6J mice. B16-F1 tumors metastasized to lymph nodes in 30% of mice, whereas B16?4+ tumors generated lymph node metastases in 80% of mice. B16-F1 melanoma cells that were deficient in ?4 integrins (B16?4-) were nontumorigenic. Collectively, these data show that the ?4 integrin expressed by melanoma cells contributes to tumorigenesis and may also facilitate metastasis to regional lymph nodes by promoting stable adhesion of melanoma cells to the lymphatic vasculature.

Rebhun, Robert B; Cheng, Hua; Gershenwald, Jeffrey E; Fan, Dominic; Fidler, Isaiah J; Langley, Robert R

2010-01-01

112

Polarized rat uterine epithelium in vitro: constitutive expression of estrogen-induced proteins.  

PubMed

The hormonal responsiveness of immature rat primary uterine epithelial (UE) cells, cultured in a serum-free, phenol red-free defined medium, was examined under conditions which allowed the UE cells to reestablish their polarized phenotype. In the absence of estradiol and phenol red UE cells proliferated to confluence, achieving cell densities equal to those reached by UE cells cultured in the presence of estradiol. The expression of marker proteins, characteristic of the in vivo response of the uterus to estrogen, i.e. the adhesion molecule cell CAM 105, complement component C3, the secretory component of the immunoglobulin A receptor, and keratan sulfate proteoglycan, by polarized cultures of UE cells proved to be independent of estrogen in vitro. Polarized UE cells required the presence of estrogen to maintain integrity of their monolayer and did exhibit a dose-dependent response to estradiol in vitro in terms of cell growth (hypertrophy) and the secretion of two proteins not previously described as estrogen response markers. UE cell secretion, in particular apical secretion, was stimulated by estradiol but not by progesterone, dexamethasone, or testosterone. Progesterone failed to down-regulate the polarized UE cell responses to estradiol. Collectively, these observations suggest that many of the responses which nominally characterize the action of estrogen on the UE cell in vivo are likely to be initiated by agents other than estrogen, e.g. growth factors. PMID:1727726

Julian, J; Carson, D D; Glasser, S R

1992-01-01

113

Constitutive neuropeptide Y Y4 receptor expression in human colonic adenocarcinoma cell lines  

PubMed Central

Three human adenocarcinoma cell lines, Colony-24 (Col-24), Col-6 and Col-1 have been studied as confluent epithelial layers able to transport ions vectorially in response to basolateral vasoactive intestinal polypeptide (VIP) and pancreatic polypeptides (PP). Different species PP stimulated responses in Col-24 with Y4-like pharmacology. Bovine (b)PP, human (h)PP and porcine (p)PP were equipotent (EC50 values 3.0?–?5.0?nM) while rat (r)PP, avian (a)PP and [Leu31, Pro34]PYY (Pro34PYY) were significantly less potent. PYY was inactive. The PP pharmacology in Col-1 was comparable with Col-24. However, Col-6 cells were different; pPP had an EC50 intermediate (22.0?nM) between that of bPP (3.0?nM) and hPP (173.2?nM), with aPP and rPP being at least a further fold less potent. Deamidation of Tyr36 in bPP (by O-methylation or hydroxylation) or removal of the residue resulted in significant loss of activity in Col-24. GR231118 (1??M) had no PP-like effects. In Col-24 and Col-1, GR231118 significantly attenuated bPP (30?nM) or hPP (100?nM) responses, but it did not alter bPP responses in Col-6. BIBP3226 and GR231118 both inhibited Y1-mediated responses which were only present in Col-6. RT?–?PCR analysis confirmed the presence of hY4 receptor mRNA in Col-24 and Col-1 epithelia but a barely visible hY4 product was observed in Col-6 and we suggest that an atypical Y4 receptor is expressed in this cell line.

Cox, Helen M; Tough, Iain R; Zandvliet, Dorothea W J; Holliday, Nicholas D

2001-01-01

114

A secretory protease inhibitor requires androgens for its expression in male sex accessory tissues but is expressed constitutively in pancreas.  

PubMed Central

A full length cDNA clone encoding a mouse prostatic secretory glycoprotein (p12) whose synthesis is dependent upon testicular androgens has been cloned and characterized. The predicted amino acid sequence of p12 shares extensive homology with several members of the Kazal family of secretory protease inhibitors, in particular the pancreatic secretory trypsin inhibitors. In agreement with sequence data, prostatic secretory p12, purified from mouse ventral prostate secretion, exhibits anti-trypsin activity. Steady-state levels of protease inhibitor mRNA in ventral prostate are reduced from approximately 0.06% in normal mice to undetectable after androgen withdrawal but are inducible within 4 h by re-administration of testosterone. Androgen-dependent expression of the secretory protease inhibitor mRNA was also observed in coagulating gland and seminal vesicle. In seminal vesicle, a tissue of different embryonic origin to the prostate, the kinetics of secretory protease inhibitor mRNA loss after castration are not as rapid as in the ventral prostate and coagulating gland. Low-level androgen independent expression was also observed in the pancreas. There appears to be a single gene for this secretory protease inhibitor and yet expression is markedly stimulated by testosterone in the sex accessory tissues and unaffected by this hormone in the pancreas. Images Fig. 3. Fig. 4. Fig. 5. Fig. 6. Fig. 7.

Mills, J S; Needham, M; Parker, M G

1987-01-01

115

Human interleukin 1 beta is not secreted from hamster fibroblasts when expressed constitutively from a transfected cDNA  

PubMed Central

To understand the secretion and processing of interleukin-1 (IL-1), a Chinese hamster fibroblast cell line (R1610) was transfected with a human IL-1 beta cDNA under the control of the SV40 early promoter and linked to the gene for neomycin resistance. After selecting for transfected cells resistant to G418, two clones were found to constitutively express the IL-1 beta 31-kD precursor which was almost exclusively located in the cytosol. Pulse-chase experiments failed to show any secretion of IL-1 and very little IL-1 activity was detectable in cell supernatants. Furthermore, surface membrane IL-1 activity could not be detected, although low levels of activity could be released upon brief trypsin treatment. Therefore, unlike monocytes, these fibroblast cells lack the mechanism for secreting and processing of IL-1 beta.

1988-01-01

116

Loss-of-Function of Constitutive Expresser of Pathogenesis Related Genes5 Affects Potassium Homeostasis in Arabidopsis thaliana  

PubMed Central

Here, we demonstrate that the reduction in leaf K+ observed in a mutant previously identified in an ionomic screen of fast neutron mutagenized Arabidopsis thaliana is caused by a loss-of-function allele of CPR5, which we name cpr5-3. This observation establishes low leaf K+ as a new phenotype for loss-of-function alleles of CPR5. We investigate the factors affecting this low leaf K+ in cpr5 using double mutants defective in salicylic acid (SA) and jasmonic acid (JA) signalling, and by gene expression analysis of various channels and transporters. Reciprocal grafting between cpr5 and Col-0 was used to determine the relative importance of the shoot and root in causing the low leaf K+ phenotype of cpr5. Our data show that loss-of-function of CPR5 in shoots primarily determines the low leaf K+ phenotype of cpr5, though the roots also contribute to a lesser degree. The low leaf K+ phenotype of cpr5 is independent of the elevated SA and JA known to occur in cpr5. In cpr5 expression of genes encoding various Cyclic Nucleotide Gated Channels (CNGCs) are uniquely elevated in leaves. Further, expression of HAK5, encoding the high affinity K+ uptake transporter, is reduced in roots of cpr5 grown with high or low K+ supply. We suggest a model in which low leaf K+ in cpr5 is driven primarily by enhanced shoot-to-root K+ export caused by a constitutive activation of the expression of various CNGCs. This activation may enhance K+ efflux, either indirectly via enhanced cytosolic Ca2+ and/or directly by increased K+ transport activity. Enhanced shoot-to-root K+ export may also cause the reduced expression of HAK5 observed in roots of cpr5, leading to a reduction in uptake of K+. All ionomic data presented is publically available at www.ionomicshub.org.

Borghi, Monica; Rus, Ana; Salt, David E.

2011-01-01

117

Novel high-level constitutive expression system, pHCE vector, for a convenient and cost-effective soluble production of human tumor necrosis factor-?  

Microsoft Academic Search

A new E. coli expression system, the pHCE-IIB vector, using a constitutively expressing HCE promoter derived upstream from the d-amino acid aminotransferase (d-AAT) gene of Geobacillus toebii, was developed for the high-level expression of foreign proteins without induction. The expression efficiency of recombinant human tumor necrosis factor-a (rhTNFa) using pHCE-IIB was compared with that of the pET14B vector under the

Haryoung Poo; Jae Jun Song; Seung-Pyo Hong; Yoon-Ho Choi; Sun Woo Yun; Jin-Ho Kim; Sang Chul Lee; Sung-Goo Lee; Moon Hee Sung

2002-01-01

118

Expression of constitutively active erythropoietin receptor in pyramidal neurons of cortex and hippocampus boosts higher cognitive functions in mice  

Microsoft Academic Search

Background  Erythropoietin (EPO) and its receptor (EPOR) are expressed in the developing brain and their transcription is upregulated\\u000a in adult neurons and glia upon injury or neurodegeneration. We have shown neuroprotective effects and improved cognition in\\u000a patients with neuropsychiatric diseases treated with EPO. However, the critical EPO targets in brain are unknown, and separation\\u000a of direct and indirect effects has remained

Derya Sargin; Ahmed El-Kordi; Amit Agarwal; Michael Müller; Sonja M Wojcik; Imam Hassouna; Swetlana Sperling; Klaus-Armin Nave; Hannelore Ehrenreich

2011-01-01

119

Regulation of gene amplification and expression in cells that constitutively express a temperature sensitive SV40 T-antigen.  

PubMed Central

Simian cells have been transformed with SV40 origin-defective recombinant plasmids containing the tsA209 T-antigen gene. These plasmids contain deletions of either 5 or 52 nucleotides that include the BglI site at the SV40 ori, are defective for replication in COS-1 cells but retain a functional SV40 early promoter. Two cell lines transformed with these plasmids, U4 and S7, and their respective clonal derivatives E5 and F11, contain the tsA209 T-antigen gene integrated into the cell DNA and express T-antigen as detected by immunoprecipitation and immunofluorescence. These cells behave as ts-COS cells, since they complement in a temperature dependent manner the replication of an SV40 derived recombinant plasmid. When transfected with recombinant plasmids containing the chloramphenicol acetyl transferase (CAT) gene cloned into SV40 replicons, ts-COS cells were able to regulate the induction of the CAT activity by temperature. The ratios of CAT activity observed at permissive versus restrictive temperature were in the range of 20-400. Thus, these ts-COS cells are useful systems for the regulated expression of cloned genes in simian cells. Images

Portela, A; de la Luna, S; Melero, J A; Vara, J; Jimenez, A; Ortin, J

1985-01-01

120

Amphotericin B severely affects expression and activity of the endothelial constitutive nitric oxide synthase involving altered mRNA stability  

PubMed Central

The therapeutic use of the antifungal drug amphotericin B (AmB) is limited due to severe side effects like glomerular vasoconstriction and risk of renal failure during AmB administration. As nitric oxide (NO) has substantial functions in renal autoregulation, we have determined the effects of AmB on endothelial constitutive NO synthase (ecNOS) expression and activity in human and rat endothelial cell cultures.AmB used at concentrations of 0.6 to 1.25??g?ml?1 led to increases in ecNOS mRNA and protein expression as well as NO production. This was the result of an increased ecNOS mRNA half-life. In contrast, incubation of cells with higher albeit subtoxic concentrations of AmB (2.5–5.0??g?ml?1) resulted in a decrease or respectively in completely abolished ecNOS mRNA and protein expression with a strongly reduced or inhibited ecNOS activity, due to a decrease of ecNOS mRNA half-life. None of the AmB concentrations affected promoter activity as found with a reporter gene construct stably transfected into ECV304 cells.Thus, our experiments show a concentration-dependent biphasic effect of AmB on expression and activity of ecNOS, an effect best explained by AmB influencing ecNOS mRNA stability. In view of the known renal accumulation of this drug the results reported here could help to elucidate its renal toxicity.

Suschek, Christoph Viktor; Bonmann, Eckhard; Kleinert, Hartmut; Wenzel, Michael; Mahotka, Csaba; Kolb, Hubert; Forstermann, Ulrich; Gerharz, Claus-Dieter; Kolb-Bachofen, Victoria

2000-01-01

121

Genetic Background Modulates Gene Expression Profile Induced by Skin Irradiation in Ptch1 Mice  

SciTech Connect

Purpose: Ptch1 germ-line mutations in mice predispose to radiation-induced basal cell carcinoma of the skin, with tumor incidence modulated by the genetic background. Here, we examined the possible mechanisms underlying skin response to radiation in F1 progeny of Ptch1{sup neo67/+} mice crossed with either skin tumor-susceptible (Car-S) or -resistant (Car-R) mice and X-irradiated (3 Gy) at 2 days of age or left untreated. Methods and Materials: We conducted a gene expression profile analysis in mRNA samples extracted from the skin of irradiated or control mice, using Affymetrix whole mouse genome expression array. Confirmation of the results was done using real-time reverse-transcriptase polymerase chain reaction. Results: Analysis of the gene expression profile of normal skin of F1 mice at 4 weeks of age revealed a similar basal profile in the nonirradiated mice, but alterations in levels of 71 transcripts in irradiated Ptch1{sup neo67/+} mice of the Car-R cross and modulation of only eight genes in irradiated Ptch1{sup neo67/+} mice of the Car-S cross. Conclusions: These results indicate that neonatal irradiation causes a persistent change in the gene expression profile of the skin. The tendency of mice genetically resistant to skin tumorigenesis to show a more complex pattern of transcriptional response to radiation than do genetically susceptible mice suggests a role for this response in genetic resistance to basal cell tumorigenesis.

Galvan, Antonella; Noci, Sara [Department of Experimental Oncology and Laboratories, Fondazione IRCCS Istituto Nazionale Tumori, Milan (Italy); Mancuso, Mariateresa; Pazzaglia, Simonetta; Saran, Anna [ENEA Laboratories, Rome (Italy); Dragani, Tommaso A. [Department of Experimental Oncology and Laboratories, Fondazione IRCCS Istituto Nazionale Tumori, Milan (Italy)], E-mail: tommaso.dragani@istitutotumori.mi.it

2008-12-01

122

Congress's Constitution  

Microsoft Academic Search

Congress has significantly more constitutional power than we are accustomed to seeing it exercise. By failing to make effective use of its power, Congress has invited the other branches to fill the vacuum, resulting in a constitutional imbalance. This Article considers a number of constitutional tools that individual houses—and even individual members—of Congress, acting alone, can deploy in interbranch conflicts.

Josh Chafetz

2012-01-01

123

Molecular characterization of the constitutive expression of the plasma platelet-activating factor acetylhydrolase gene in macrophages.  

PubMed Central

Plasma platelet-activating factor acetylhydrolase (PAF-AH) is a phospholipase that inactivates platelet-activating factor (PAF) and PAF-like lipids to generate products with little or no biological activity. The levels of circulating PAF-AH correlate with several disease syndromes. We previously reported that mediators of inflammation regulate the expression of the human PAF-AH gene at the transcriptional level. In the present paper, we characterize the constitutive expression of plasma PAF-AH using the mouse gene as a model system, and we report comparative results obtained using human and mouse promoter constructs. We first cloned, sequenced and analysed the promoter region of the murine plasma PAF-AH (mPAF-AH) gene and found that this gene lacks a canonical TATA box. We demonstrated that the cis -elements required for basal transcription are localized within the -316 to -68 bp region. In vitro band-shift and supershift assays showed that Sp1 and Sp3 transcription factors from RAW264.7 and J774A.1 macrophage nuclear extracts bound strongly to a distal GC-rich site within -278/-243 [specificity protein (Sp-A)] and to a proximal TC-rich motif within -150/-114 (Sp-B). In addition, we observed weak binding to a GA-rich site within -110/-82 (Sp-C). The regions containing Sp-B and Sp-C are highly conserved between the human and mouse genes. Forced expression of Sp1 or Sp3 in Sp-lacking Drosophila SL2 cells induced markedly the activity of the exogenous mPAF-AH promoter in a dose-dependent manner, and this induction was dependent on the presence of intact Sp-A and Sp-B. Interestingly, we found that the Sp1- and Sp3-associated DNA-binding activities increased during the maturation of primary human monocytes into macrophages in cell culture. These results demonstrate that Sp1 and Sp3 are key factors that contribute to the basal, constitutive transcription of the plasma PAF-AH gene in macrophages.

Wu, Xiaoqing; McIntyre, Thomas M; Zimmerman, Guy A; Prescott, Stephen M; Stafforini, Diana M

2003-01-01

124

Constitutive expression of the cloned phenol hydroxylase gene(s) from Alcaligenes eutrophus JMP134 and concomitant trichloroethylene oxidation.  

PubMed Central

Given the demonstrated phenol-dependent trichloroethylene (TCE) degradation in Alcaligenes eutrophus JMP134 (A. R. Harker and Y. Kim, Appl. Environ. Microbiol. 56:1179-1181, 1990), this work represents a purposeful effort to create a constitutive degrader of TCE. Genes responsible for phenol hydroxylase activity were identified by Tn5 transposon mutagenesis. Mutants lacked both phenol hydroxylase and catechol 2,3-dioxygenase activities. Southern blot analysis of total DNA showed that all mutants contained a single copy of Tn5 inserted in the same 11.5-kb EcoRI fragment. Complementation with a cosmid-based gene bank constructed from A. eutrophus AEK101 allowed the isolation of three recombinant cosmids carrying a common 16.8-kb HindIII fragment. Deletion and subcloning analysis localized the genes involved in phenol hydroxylase and catechol 2,3-dioxygenase activities. Partial sequence analysis of regions within the cloned phenol hydroxylase-expressing fragment shows significant homology to the oxygenase and oxidoreductase subunits of toluene-3-monooxygenase from Pseudomonas pickettii. The Tn5-induced phl mutant, carrying a recombinant plasmid expressing the phenol hydroxylase activity, degrades TCE in the absence of induction. Complete removal of TCE (50 microM) within 24 h was observed in minimal medium containing only 0.05% ethanol as a carbon source. The bacterium removed 200 microM TCE to below detectable levels within 2 days under noninducing and nonselective conditions.

Kim, Y; Ayoubi, P; Harker, A R

1996-01-01

125

The constitutive expression of Arabidopsis plasmodesmal-associated class 1 reversibly glycosylated polypeptide impairs plant development and virus spread  

PubMed Central

Arabidopsis class 1 reversibly glycosylated polypeptides (C1RGPs) were shown to be plasmodesmal-associated proteins. Transgenic tobacco (Nicotiana tabacum) plants constitutively expressing GFP tagged AtRGP2 under the control of the CaMV 35S promoter are stunted, have a rosette-like growth pattern, and in source leaves exhibit strong chlorosis, increased photoassimilate retention and starch accumulation that results in elevated leaf specific fresh and dry weights. Basal callose levels around plasmodesmata (Pd) of leaf epidermal cells in transgenic plants are higher than in WT. Such a phenotype is characteristic of virus-infected plants and some transgenic plants expressing Pd-associated viral movement proteins (MP). The local spread of Tobacco mosaic virus (TMV) is inhibited in AtRGP2:GFP transgenics compared to WT. Taken together these observations suggest that overexpression of the AtRGP2:GFP leads to a reduction in Pd permeability to photoassimilate, thus lowering the normal rate of translocation from source leaves to sink organs. Such a reduction may also inhibit the local cell-to-cell spread of viruses in transgenic plants. The observed reduction in Pd permeability could be due to a partial Pd occlusion caused either by the accumulation of AtRGP2:GFP fusion in Pd, and/or by constriction of Pd by the excessive callose accumulation.

Zavaliev, Raul; Sagi, Guy; Gera, Abed; Epel, Bernard L.

2010-01-01

126

Strain background influences neurotoxicity and behavioral abnormalities in mice expressing the tetracycline transactivator  

PubMed Central

The tet-off system has been widely used to create transgenic models of neurological disorders including Alzheimer’s, Parkinson’s, Huntington’s, and prion disease. The utility of this system lies in the assumption that the tetracycline transactivator (TTA) acts as an inert control element and does not contribute to phenotypes under study. Here we report that neuronal expression of TTA can affect hippocampal cytoarchitecture and behavior in a strain-dependent manner. While studying neurodegeneration in two tet-off Alzheimer’s disease models, we unexpectedly discovered neuronal loss within the dentate gyrus of single transgenic TTA controls. Granule neurons appeared most sensitive to TTA exposure during postnatal development, and doxycycline treatment during this period was neuroprotective. TTA-induced degeneration could be rescued by moving the transgene onto a congenic C57BL/6J background, and recurred on re-introduction of either CBA or C3H/He backgrounds. Quantitative trait analysis of B6C3 F2 TTA mice identified a region on Chromosome 14 that contains a major modifier of the neurodegenerative phenotype. Although B6 mice were resistant to degeneration, they were not ideal for cognitive testing. F1 offspring of TTA C57BL/6J and 129X1/SvJ, FVB/NJ, or DBA/1J showed improved spatial learning, but TTA expression caused subtle differences in contextual fear conditioning on two of these backgrounds indicating that strain and genotype can interact independently under different behavioral settings. All model systems have limitations that should be recognized and mitigated where possible; our findings stress the importance of mapping the effects caused by TTA alone when working with tet-off models.

Han, Harry J.; Allen, Carolyn C.; Buchovecky, Christie M.; Yetman, Michael J.; Born, Heather A.; Marin, Miguel A.; Rodgers, Shaefali P.; Song, Bryan J.; Lu, Hui-Chen; Justice, Monica J.; Probst, Frank J.; Jankowsky, Joanna L.

2012-01-01

127

Ortho-Aminoazotoluene activates mouse Constitutive Androstane Receptor (mCAR) and increases expression of mCAR target genes  

PubMed Central

2'-3-dimethyl-4-aminoazobenzene (ortho-aminoazotoluene, OAT) is an azo dye and a rodent carcinogen that has been evaluated by the International Agency for Research on Cancer (IARC) as a possible (class 2B) human carcinogen. Its mechanism of action remains unclear. We examined the role of the xenobiotic receptor Constitutive Androstane Receptor (CAR, NR1I3) as a mediator of the effects of OAT. We found that OAT increases mouse CAR (mCAR) transactivation in a dose-dependent manner. This effect is specific because another closely related azo dye, 3'-methyl-4-dimethyl-aminoazobenzene (3'MeDAB), did not activate mCAR. Real-time Q-PCR analysis in wild-type C57BL/6 mice revealed that OAT induces the hepatic mRNA expression of the following CAR target genes: Cyp2b10, Cyp2c29, Cyp3a11, Ugt1a1, Mrp4, Mrp2 and c-Myc. CAR-null (Car?/?) mice showed no increased expression of these genes following OAT treatment, demonstrating that CAR is required for their OAT dependent induction. The OAT-induced CAR-dependent increase of Cyp2b10 and c-Myc expression was confirmed by Western blotting. Immunohistochemistry analysis of wild-type and Car?/? livers showed that OAT did not acutely induce hepatocyte proliferation, but at much later time points showed an unexpected CAR-dependent proliferative response. These studies demonstrate that mCAR is an OAT xenosensor, and indicate that at least some of the biological effects of this compound are mediated by this nuclear receptor.

Smetanina, Mariya A.; Pakharukova, Mariya Y.; Kurinna, Svitlana M.; Dong, Bingning; Hernandez, Juan P.; Moore, David D.; Merkulova, Tatyana I.

2011-01-01

128

Altered expression of constitutive type and inducible type heat shock proteins in response of d-galactosamine-sensitized mice to lipopolysaccharide as an experimental endotoxic shock model  

Microsoft Academic Search

The expression of heat shock proteins (HSPs) as stress-induced proteins was studied in mice injected with d-galactosamine (D-GalN) and lipopolysaccharide (LPS) as an experimental endotoxic shock model. The expression of constitutive type heat shock protein 70 (HSC70) was significantly reduced in livers of mice injected with d-galactosamine and lipopolysaccharide, while its expression was unaffected in livers of mice injected with

A Morikawa; Y Kato; T Sugiyama; N Koide; M Kawai; M Fukada; T Yoshida; T Yokochi

1998-01-01

129

Ortho-aminoazotoluene activates mouse constitutive androstane receptor (mCAR) and increases expression of mCAR target genes  

SciTech Connect

2'-3-dimethyl-4-aminoazobenzene (ortho-aminoazotoluene, OAT) is an azo dye and a rodent carcinogen that has been evaluated by the International Agency for Research on Cancer (IARC) as a possible (class 2B) human carcinogen. Its mechanism of action remains unclear. We examined the role of the xenobiotic receptor Constitutive Androstane Receptor (CAR, NR1I3) as a mediator of the effects of OAT. We found that OAT increases mouse CAR (mCAR) transactivation in a dose-dependent manner. This effect is specific because another closely related azo dye, 3'-methyl-4-dimethyl-aminoazobenzene (3'MeDAB), did not activate mCAR. Real-time Q-PCR analysis in wild-type C57BL/6 mice revealed that OAT induces the hepatic mRNA expression of the following CAR target genes: Cyp2b10, Cyp2c29, Cyp3a11, Ugt1a1, Mrp4, Mrp2 and c-Myc. CAR-null (Car{sup -/-}) mice showed no increased expression of these genes following OAT treatment, demonstrating that CAR is required for their OAT dependent induction. The OAT-induced CAR-dependent increase of Cyp2b10 and c-Myc expression was confirmed by Western blotting. Immunohistochemistry analysis of wild-type and Car{sup -/-} livers showed that OAT did not acutely induce hepatocyte proliferation, but at much later time points showed an unexpected CAR-dependent proliferative response. These studies demonstrate that mCAR is an OAT xenosensor, and indicate that at least some of the biological effects of this compound are mediated by this nuclear receptor. - Highlights: > The azo dye and mouse carcinogen OAT is a very effective mCAR activator. > OAT increases mCAR transactivation in a dose-dependent manner. > OAT CAR-dependently increases the expression of a specific subset of CAR target genes. > OAT induces an unexpectedly deferred, but CAR-dependent hepatocyte proliferation.

Smetanina, Mariya A., E-mail: maria.smetanina@gmail.com [Department of Molecular and Cellular Biology, Baylor College of Medicine, 1 Baylor Plaza, Houston, TX 77030 (United States); Laboratory of Gene Expression Control, Institute of Cytology and Genetics of the Siberian Branch of the Russian Academy of Sciences, prospekt Lavrentyeva 10, Novosibirsk 630090 (Russian Federation); Group of Pharmacogenomics, Institute of Chemical Biology and Fundamental Medicine of the Siberian Branch of the Russian Academy of Sciences, prospekt Lavrentyeva 8, Novosibirsk 630090 (Russian Federation); Pakharukova, Mariya Y. [Laboratory of Gene Expression Control, Institute of Cytology and Genetics of the Siberian Branch of the Russian Academy of Sciences, prospekt Lavrentyeva 10, Novosibirsk 630090 (Russian Federation); Kurinna, Svitlana M. [Department of Biochemistry and Molecular Biology, Unit 1000, University of Texas M. D. Anderson Cancer Center, 1515 Holcombe Blvd., Houston, TX 77030 (United States); Dong, Bingning; Hernandez, Juan P.; Moore, David D. [Department of Molecular and Cellular Biology, Baylor College of Medicine, 1 Baylor Plaza, Houston, TX 77030 (United States); Merkulova, Tatyana I. [Laboratory of Gene Expression Control, Institute of Cytology and Genetics of the Siberian Branch of the Russian Academy of Sciences, prospekt Lavrentyeva 10, Novosibirsk 630090 (Russian Federation)

2011-08-15

130

Islet beta cell expression of constitutively active Akt1/PKB alpha induces striking hypertrophy, hyperplasia, and hyperinsulinemia.  

PubMed

The phosphoinositide 3-kinase-Akt/PKB pathway mediates the mitogenic effects various nutrients and growth factors in cultured cells. To study its effects in vivo in pancreatic islet beta cells, we created transgenic mice that expressed a constitutively active Akt1/PKB alpha linked to an Insulin gene promoter. Transgenic mice exhibited a grossly visible increase in islet mass, largely due to proliferation of insulin-containing beta cells. Morphometric analysis verified a six-fold increase in beta cell mass/pancreas, a two-fold increase in 5-bromo-2'-deoxyuridine incorporation, a four-fold increase in the number of beta cells per pancreas area, and a two-fold increase in cell size in transgenic compared with wild-type mice at 5 weeks. At least part of the increase in beta cell number may be accounted for by neogenesis, defined by criteria that include beta cells proliferating from ductular epithelium, and by a six-fold increase in the number of single and doublet beta cells scattered throughout the exocrine pancreas of the transgenic mice. Glucose tolerance was improved, and fasting as well as fed insulin was greater compared with wild-type mice. Glucose-stimulated insulin secretion was maintained in transgenic mice, which were resistant to streptozotocin-induced diabetes. We conclude that activation of the Akt1/PKB alpha pathway affects islet beta cell mass by alteration of size and number. PMID:11733558

Bernal-Mizrachi, E; Wen, W; Stahlhut, S; Welling, C M; Permutt, M A

2001-12-01

131

CCAAT enhancer-binding protein beta regulates constitutive gene expression during late stages of monocyte to macrophage differentiation.  

PubMed

Human monocyte to macrophage differentiation is accompanied by pronounced phenotypical changes and generally proceeds in the absence of proliferation. The molecular events governing this process are poorly understood. Here, we studied the regulation of the macrophage-specific chitotriosidase (CHIT1) gene promoter to gain insights into the mechanisms of transcriptional control during the differentiation of human blood monocytes into macrophages. We used transient transfections to define a cell type-specific minimal promoter that was mainly dependent on a proximal C/EBP motif that bound multiple C/EBP factors in gel shift assays. In depth analysis of occupied promoter elements using in vivo footprinting and chromatin immunoprecipitation analyses demonstrated the differentiation-associated recruitment of C/EBPbeta and PU.1 at the proximal promoter in parallel with CHIT1 mRNA induction. Notably, the induction of C/EBPbeta promoter binding strongly correlated with increased nuclear levels of Thr-235-phosphorylated C/EBPbeta protein during the differentiation process, whereas C/EBPbeta mRNA and total protein expression remained relatively stable. Our data suggest an important constitutive gene regulatory function for C/EBPbeta in differentiated macrophages but not in human blood monocytes. PMID:17540774

Pham, Thu-Hang; Langmann, Sabine; Schwarzfischer, Lucia; El Chartouni, Carol; Lichtinger, Monika; Klug, Maja; Krause, Stefan W; Rehli, Michael

2007-05-31

132

Inactivation of the Moraxella catarrhalis Superoxide Dismutase SodA Induces Constitutive Expression of Iron-Repressible Outer Membrane Proteins  

PubMed Central

Many pathogens produce one or more superoxide dismutases (SODs), enzymes involved in the detoxification of endogenous and exogenous reactive oxygen species that are encountered during the infection process. One detectable cytoplasmic SOD was identified in the human mucosal pathogen Moraxella catarrhalis, and the gene responsible for the SOD activity, sodA, was isolated from a recent pediatric clinical isolate (strain 7169). Sequence analysis of the cloned M. catarrhalis 7169 DNA fragment revealed an open reading frame of 618 bp encoding a polypeptide of 205 amino acids with 48 to 67% identity to known bacterial manganese-cofactored SODs. An isogenic M. catarrhalis sodA mutant was constructed in strain 7169 by allelic exchange. In contrast to the wild-type 7169, the 7169::sodK20 mutant was severely attenuated for aerobic growth, even in rich medium containing supplemental amino acids, and exhibited extreme sensitivity to the redox-active agent methyl viologen. The ability of recombinant SodA to rescue the aerobic growth defects of E. coli QC774, a sodA sodB-deficient mutant, demonstrated the functional expression of SOD activity by cloned M. catarrhalis sodA. Indirect SOD detection assays were used to visualize both native and recombinant SodA activity in bacterial lysates. This study demonstrates that M. catarrhalis SodA plays a critical role in the detoxification of endogenous, metabolically produced oxygen radicals. In addition, the outer membrane protein (OMP) profile of 7169::sodK20 was consistent with iron starvation in spite of growth under iron-replete conditions. This novel observation indicates that M. catarrhalis strains lacking SodA constitutively express immunogenic OMPs previously described as iron repressible, and this potentially attenuated mutant strain may be an attractive vaccine candidate.

Luke, Nicole R.; Karalus, Richard J.; Campagnari, Anthony A.

2002-01-01

133

NnSR1, a class III non-S-RNase constitutively expressed in styles, is induced in roots and stems under phosphate deficiency in Nicotiana alata.  

PubMed

Background and Aims Non-S-ribonucleases (non-S-RNases) are class III T2 RNases constitutively expressed in styles of species with S-RNase-based self-incompatibility. So far, no function has been attributed to these RNases. The aim of this work is to examine if NnSR1, a non-S-RNase from Nicotiana alata, is induced under conditions of phosphate (Pi) deprivation. The hypothesis is that under Pi-limited conditions, non-S-RNase functions may resemble the role of S-like RNases. To date, the only RNases reported to be induced by Pi deficiency are class I and class II S-like RNases, which are phylogenetically different from the class III clade of RNases. Methods Gene and protein expression of NnSR1 were assayed in plants grown hydroponically with and without Pi, by combining RT-PCR, immunoblot and enzymatic activity approaches. Key Results NnSR1 transcripts were detected in roots 7 d after Pi deprivation and remained stable for several days. Transcript expression was correlated based on Pi availability in the culture medium. Antiserum against a peptide based on a hypervariable domain of NnSR1 recognized NnSR1 in roots and stems but not leaves exposed to Pi shortage. NnSR1 was not detected in culture medium and was pelleted with the microsomal fraction, suggesting that it was membrane-associated or included in large compartments. The anti-NnSR1 inhibited selectively the enzymatic activity of a 31-kDa RNase indicating that NnSR1 was induced in an enzymatically active form. Conclusions The induction of NnSR1 indicates that there is a general recruitment of all classes of T2 RNases in response to Pi shortage. NnSR1 appears to have regained ancestral functions of class III RNases related to strategies to cope with Pi limitation and also possibly with other environmental challenges. This constitutes the first report for a specific function of class III RNases other than S-RNases. PMID:24047716

Rojas, Hernán J; Roldán, Juan A; Goldraij, Ariel

2013-09-18

134

Constitutional Issues and Iowa.  

ERIC Educational Resources Information Center

|Important constitutional issues are presented in a manner appropriate for use in the classroom. Case studies and events from the history of Iowa are used to illuminate the Constitution and Bill of Rights. Freedom of expression and students' rights are discussed in "The Black Armband Case"; free exercise of religion as won by the Iowa's Amish is…

Gore, Deborah, Ed.

1987-01-01

135

Constitutional Displacement  

Microsoft Academic Search

This Article examines the intersection between territory and constitutional liberty. Territoriality, as defined by Robert Sack, is the attempt to affect, influence, or control people, phenomena, and relationships by delimiting and asserting control over a geographic area. Territoriality affects constitutional liberty in profound ways. These effects have been apparent in certain infamous historical episodes, including the territoriality of racial segregation,

Timothy Zick

2009-01-01

136

Plant Density and Nutrient Availability Constrain Constitutive and Wound-induced Expression of Trypsin Inhibitors in Brassica napus  

Microsoft Academic Search

We investigated the effects of plant density on plant size, leaf total soluble protein content, and constitutive and wound-induced levels of proteinaceous trypsin inhibitors in pot-grown Brassica napus seedlings in two greenhouse studies. We manipulated plant density by varying the number of intraspecific neighbors surrounding a target plant in the center of each pot. In general, constitutive and induced levels

Donald F. Cipollini; Joy Bergelson

2001-01-01

137

Constitutive Expression of the Maize Genes B1 and C1 in Transgenic Hi II Maize Results in Differential Tissue Pigmentation and Generates Resistance to Helicoverpa zea  

Technology Transfer Automated Retrieval System (TEKTRAN)

Anthocyanin biosynthesis in maize protects tissues from biotic and abiotic stresses. Constitutive expression of the maize B1 and C1 genes, which induces anthocyanin biosynthesis, resulted in transgenic plants with varied phenotypes. Some colored leaves were substantially resistant to thrips damage...

138

Constitutive expression of the nifA gene activates associative nitrogen fixation of Enterobacter gergoviae 57-7, an opportunistic endophytic diazotroph  

Microsoft Academic Search

Aims: This study was undertaken to investigate whether a nitrogen-fixing bac- terium Enterobacter gergoviae 57-7, which was isolated from surface-sterilized maize (Zea mays L.) roots, can colonize in roots and whether constitutive expression of the nifA gene encoding the transcriptional activator of nitroge- nase genes can activate nif gene expression in planta. Methods and Results: Maize seedlings grown in an

Q. An; Y. Dong; W. Wang; Y. Li; J. Li

2007-01-01

139

Constitutively High Expression of the Histidine Biosynthetic Pathway Contributes to Nickel Tolerance in Hyperaccumulator PlantsW?  

PubMed Central

Plants that hyperaccumulate Ni exhibit an exceptional degree of Ni tolerance and the ability to translocate Ni in large amounts from root to shoot. In hyperaccumulator plants in the genus Alyssum, free His is an important Ni binding ligand that increases in the xylem proportionately to root Ni uptake. To determine the molecular basis of the His response and its contribution to Ni tolerance, transcripts representing seven of the eight enzymes involved in His biosynthesis were investigated in the hyperaccumulator species Alyssum lesbiacum by RNA gel blot analysis. None of the transcripts changed in abundance in either root or shoot tissue when plants were exposed to Ni, but transcript levels were constitutively higher in A. lesbiacum than in the congeneric nonaccumulator A. montanum, especially for the first enzyme in the biosynthetic pathway, ATP-phosphoribosyltransferase (ATP-PRT). Comparison with the weak hyperaccumulator A. serpyllifolium revealed a close correlation between Ni tolerance, root His concentration, and ATP-PRT transcript abundance. Overexpression of an A. lesbiacum ATP-PRT cDNA in transgenic Arabidopsis thaliana increased the pool of free His up to 15-fold in shoot tissue, without affecting the concentration of any other amino acid. His-overproducing lines also displayed elevated tolerance to Ni but did not exhibit increased Ni concentrations in either xylem sap or shoot tissue, suggesting that additional factors are necessary to recapitulate the complete hyperaccumulator phenotype. These results suggest that ATP-PRT expression plays a major role in regulating the pool of free His and contributes to the exceptional Ni tolerance of hyperaccumulator Alyssum species.

Ingle, Robert A.; Mugford, Sam T.; Rees, Jonathan D.; Campbell, Malcolm M.; Smith, J. Andrew C.

2005-01-01

140

Constitutive high-level expression of a codon-optimized ?-fructosidase gene from the hyperthermophile Thermotoga maritima in Pichia pastoris.  

PubMed

Enzymes for use in the sugar industry are preferred to be thermotolerant. In this study, a synthetic codon-optimized gene encoding a highly thermostable ?-fructosidase (BfrA, EC 3.2.1.26) from the bacterium Thermotoga maritima was expressed in the yeast Pichia pastoris. The gradual increase of the transgene dosage from one to four copies under the control of the constitutive glyceraldehyde 3-phosphate dehydrogenase promoter had an additive effect on BfrA yield without causing cell toxicity. Maximal values of cell biomass (115 g/l, dry weight) and overall invertase activity (241 U/ml) were reached at 72 h in fed-batch fermentations using cane sugar as the main carbon source for growth. Secretion driven by the Saccharomyces cerevisiae ?-factor signal peptide resulted in periplasmic retention (44 %) and extracellular release (56 %) of BfrA. The presence of N-linked oligosaccharides did not influence the optimal activity, thermal stability, kinetic properties, substrate specificity, and exo-type action mode of the yeast-secreted BfrA in comparison to the native unglycosylated enzyme. Complete inversion of cane sugar at initial concentration of 60 % (w/v) was achieved by periplasmic BfrA in undisrupted cells reacting at pH 5.5 and 70 °C, with average productivity of 4.4 g of substrate hydrolyzed per grams of biomass (wet weight) per hour. The high yield of fully active glycosylated BfrA here attained by recombinant P. pastoris in a low-cost fermentation process appears to be attractive for the large-scale production of this thermostable enzyme useful for the manufacture of inverted sugar syrup. PMID:22821437

Menéndez, Carmen; Martínez, Duniesky; Trujillo, Luis E; Mazola, Yuliet; González, Ernesto; Pérez, Enrique R; Hernández, Lázaro

2012-07-21

141

Isolation and gene expression analysis of Arabidopsis thaliana mutants with constitutive expression of ATL2, an early elicitor-response RING-H2 zinc-finger gene.  

PubMed Central

Genes with unstable transcripts often encode proteins that play important regulatory roles. ATL2 is a member of a multigene family coding highly related RING-H2 zinc-finger proteins that may function as E3 ubiquitin ligases. ATL2 mRNA accumulation occurs rapidly and transiently after incubation with elicitors of pathogen response. We screened 50,000 M(2) families from a line that carries a fusion of pATL2 to the GUS reporter gene and isolated five mutants, which we named eca (expresión constitutiva de ATL2), that showed constitutive expression of the reporter gene. One mutant exhibits a drastic stunted phenotype while the other four grow similarly to wild type. Two early chitin-induced genes and known pathogenesis-related genes such as NPR1, PAL, and CHS are activated in all the mutants whereas members of the ATL family and PR-1 and PDF2.1, which are markers of the salicylic acid (SA) jasmonate (JA) defense-response pathways, display differential expression between the mutants. These observations indicate that the ECA gene products may function in the early steps of an elicitor-response pathway, although some of them may function at other stages on the SA or JA defense-response pathways. Likewise, the fact that ATL2 and other members of the ATL family are activated in eca mutants links the induction of this putative class of ubiquitin ligases to plant defense signaling pathways.

Serrano, Mario; Guzman, Plinio

2004-01-01

142

Identification of distinct regions of 5' flanking DNA that mediate constitutive, IFN-gamma, STAT1, and TGF-beta-regulated expression of the class II transactivator gene.  

PubMed

Class II transactivator (CIITA) is a master regulator required for constitutive and IFN-gamma-inducible expression of class II MHC genes. Although the role of CIITA is greatly appreciated, the mechanisms underlying constitutive and IFN-gamma-induced expression of CIITA are not understood. The study of CIITA induction is extremely important, but has been fraught with difficulty. This study describes for the first time a large (7-kb) fragment of 5' flanking sequences that mediates the B cell-specific, IFN-gamma-induced, and TGF-beta-suppressed expression of CIITA. This pattern of expression matches the authentic expression of the endogenous gene. Within the 7-kb fragment, sequences that lie between nucleotides -545 and -113 relative to the transcriptional start site are critical for constitutive promoter expression in B cells. In contrast, inducible activation of CIITA by IFN-gamma requires sequences contained in an additional 4 kb of upstream DNA. This region mediates an IFN-gamma response when linked to either the endogenous CIITA promoter or a heterologous promoter. A role for STAT1 in regulation of the CIITA promoter is shown by the rescue of IFN-gamma induction by expression of STAT1 in STAT1-defective U3A cells. TGF-beta significantly inhibits IFN-gamma-mediated induction of the CIITA promoter in 2fTGH fibroblasts, which indicates that the promoter is a target for TGF-beta. This inhibition is achieved by suppression of the basal promoter. This study provides a focal point for understanding the mechanism of B cell-specific, IFN-gamma-induced, and TGF-beta-suppressed expression of CIITA. PMID:9551976

Piskurich, J F; Wang, Y; Linhoff, M W; White, L C; Ting, J P

1998-01-01

143

Constitutively decreased TGFBR1 allelic expression is a common finding in colorectal cancer and is associated with three TGFBR1 SNPs  

PubMed Central

Purpose Constitutively decreased TGFBR1 allelic expression is emerging as a potent modifier of colorectal cancer risk in mice and humans. This phenotype was first observed in mice, then in lymphoblastoid cell lines from patients with microsatellite stable colorectal tumors. Patients and Methods We assessed the frequency of constitutively decreased TGFBR1 allelic expression and association with SNPs covering the TGFBR1 locus using RNA and DNA extracted from the peripheral blood lymphocytes of 118 consecutive patients with biopsy-proven adenocarcinoma of the colon or the rectum. Results We found that 11(9.3%) of 118 patients exhibited decreased TGFBR1 allelic expression (TGFBR1 ASE). TGFBR1 ASE was strongly associated with three SNPs in linkage disequilibrium with each other: rs7034462 (p = 7.2 × 10-4), TGFBR1*6A (p = 1.6 × 10-4) and rs11568785 (p = 1.4 × 10-4). Conclusion These results confirm the high prevalence of constitutively decreased TGFBR1 allelic expression among patients with colorectal cancer. The association of this phenotype with TGFBR1*6A, rs7034462 and rs1156875 suggests an association between TGFBR1 SNPs and colorectal cancer, which warrants additional studies.

2010-01-01

144

Antisense Suppression of a (+)-?-Cadinene Synthase Gene in Cotton Prevents the Induction of This Defense Response Gene during Bacterial Blight Infection But Not Its Constitutive Expression1[w  

PubMed Central

In cotton (Gossypium hirsutum) the enzyme (+)-?-cadinene synthase (CDNS) catalyzes the first committed step in the biosynthesis of cadinane-type sesquiterpenes, such as gossypol, that provide constitutive and inducible protection against pests and diseases. A cotton cDNA clone encoding CDNS (cdn1-C4) was isolated from developing embryos and functionally characterized. Southern analysis showed that CDNS genes belong to a large multigene family, of which five genomic clones were studied, including three pseudogenes and one gene that may represent another subfamily of CDNS. CDNS expression was shown to be induced in cotton infected with either the bacterial blight or verticillium wilt pathogens. Constructs for the constitutive or seed-specific antisense suppression of cdn1-C4 were introduced into cotton by Agrobacterium-mediated transformation. Gossypol levels were not reduced in the seeds of transformants with either construct, nor was the induction of CDNS expression affected in stems of the constitutive antisense plants infected with Verticillium dahliae Kleb. However, the induction of CDNS mRNA and protein in response to bacterial blight infection of cotyledons was completely blocked in the constitutive antisense plants. These results suggest that cdn1-C4 may be involved specifically in the bacterial blight response and that the CDNS multigene family comprises a complex set of genes differing in their temporal and spatial regulation and responsible for different branches of the cotton sesquiterpene pathway.

Townsend, Belinda J.; Poole, Andrew; Blake, Christopher J.; Llewellyn, Danny J.

2005-01-01

145

Effect of Background Correction on Cancer Classification with Gene Expression Data  

Microsoft Academic Search

This paper empirically compares six background correction methods aimed at removing unspecific background noise of the overall\\u000a signal level measured by a scanner across microarrays. Using three published cDNA microarray datasets we investigated the\\u000a effect of background correction on cancer classification in terms of the predictive performance of two classifiers (k-NN and\\u000a support vector machine with linear kernel) induced from

Adelaide Freitas; Gladys Castillo; Ana Săo Marcos

2009-01-01

146

Relationships Between Certain Background Factors of Young Adults and Their Expressed Attitudes Toward Selected Ethical Values.  

ERIC Educational Resources Information Center

The relationship between background characteristics of young adults such as sex, marital status, parenthood, income level, age, educational background, occupational level, and church participation were studied as to their influence on the ethical values of marital fidelity, honesty, and goodwill. Of 400 young adults in 52 Protestant congregations…

Johnstone, William Milton

147

Constitutive expression of interleukin 4 in vivo does not lead to the development of T helper 2 type CD8 + T cells secreting interleukin 4 or interleukin 5  

Microsoft Academic Search

Interleukin 4 (IL-4) has been shown to commit CD8+ T cells to a T helper (Th) 2 functional phenotype in vitro. To study the effects of IL-4 on CD8+ T cell development in vivo we analysed the CD8+ T cell phenotype in mice constitutively expressing IL-4. Purified CD8+ T cells from uninfected or flu infected IL-4 transgenic (tg) animals produced

Klaus Josef Erb; Sam Hou; Lisa Hyland; Joanna Kirman; Heidrun Moll; Graham Le Gros

1999-01-01

148

Constitutive expression of a fungal glucose oxidase gene in transgenic tobacco confers chilling tolerance through the activation of antioxidative defence system  

Microsoft Academic Search

Scientific evidences in the literature have shown that plants treated exogenously with micromole concentration of hydrogen\\u000a peroxide (H2O2) acquire abiotic stress tolerance potential, without substantial disturbances in the endogenous H2O2 pool. In this study, we enhanced the endogenous H2O2 content of tobacco (Nicotiana tabaccum L. cv. SR1) plants by the constitutive expression of a glucose oxidase (GO; EC 1.1.3.4) gene

Subbiyan Maruthasalam; Yi Lun Liu; Ching Mei Sun; Pei Ying Chen; Chih Wen Yu; Pei Fang Lee; Chin Ho Lin

2010-01-01

149

Inducible and constitutive transcription factors in the mammalian nervous system: control of gene expression by Jun, Fos and Krox, and CREB\\/ATF proteins  

Microsoft Academic Search

This article reviews findings up to the end of 1997 about the inducible transcription factors (ITFs) c-Jun, JunB, JunD, c-Fos, FosB, Fra-1, Fra-2, Krox-20 (Egr-2) and Krox-24 (NGFI-A, Egr-1, Zif268); and the constitutive transcription factors (CTFs) CREB, CREM, ATF-2 and SRF as they pertain to gene expression in the mammalian nervous system. In the first part we consider basic facts

T. Herdegen; J. D. Leah

1998-01-01

150

SV40-derived vectors provide effective transgene expression and inhibition of HIV1 using constitutive, conditional,and pol III promoters  

Microsoft Academic Search

Vectors based on recombinant SV40 viruses (rSV40) are highly effective in delivering transgene expression driven by constitutive promoters. We tested here whether these vectors could be used with conditional promoters and promoters using RNA polymerase III transcription, with inhibition of HIV-1 by Tat activation response (TAR) decoys as a functional measure of effective transgene delivery and activity. TAR decoys inhibit

GC Jayan; P Cordelier; C Patel; M BouHamdan; R Paul Johnson; J Lisziewicz; RJ Pomerantz; DS Strayer

2001-01-01

151

On the nature of facultative and constitutive CAM: environmental and developmental control of CAM expression during early growth of Clusia, Kalanchoe ¨, and Opuntia  

Microsoft Academic Search

The capacity to induce crassulacean acid metabolism developmentally (constitutive CAM) and to up-regulate CAM expression in response to drought stress (facul- tative CAM) was studied in whole shoots of seven species by measuring net CO2 gas exchange for up to 120 day-night cycles during early growth. In Clusia rosea, CAM was largely induced developmentally. Well-watered seedlings began their life cycle

Klaus Winter; Milton Garcia; Joseph A. M. Holtum

2008-01-01

152

Specific NF-kappaB blockade selectively inhibits tumour necrosis factor-alpha-induced COX-2 but not constitutive COX-1 gene expression in HT-29 cells.  

PubMed Central

Cyclo-oxygenase (COX) is the key regulatory enzyme of the prostaglandin/eicosanoid pathway. While COX-1 is mostly constitutively expressed, the COX-2 isoform is inducible by proinflammatory cytokines. We used an adenoviral vector containing an NF-kappaB super-repressor (Ad5IkappaB) to investigate the role of NF-kappaB in tumour necrosis factor-alpha (TNF-alpha)-mediated COX-2 gene expression in a colonic epithelial cell line. COX-1 mRNA and protein were constitutively expressed in uninfected, control Ad5LacZ- or Ad5IkappaB-infected HT-29 cells with no apparent change following TNF-alpha exposure. COX-2 mRNA and protein expression was undetectable in unstimulated cells but was strongly up-regulated after TNF-alpha stimulation in uninfected and Ad5LacZ-infected HT-29 cells. This induction was prevented in Ad5IkappaB cells. TNF-alpha increased prostaglandin E2 production by 20-fold in Ad5LacZ-infected HT-29 cells compared with uninfected cells and was significantly inhibited in Ad5IkappaB-infected cells in agreement with the COX-2 mRNA findings. We conclude that NF-kappaB activation is critical in mediating COX-2, but not COX-1 gene expression in HT-29 cells. Selective inhibition of COX-2 expression with the NF-kappaB super-repressor may be useful in distinguishing the role of inducible versus constitutive prostaglandins in intestinal function and provides greater specificity than pharmacological inhibitors. Images Figure 1 Figure 2 Figure 3

Jobin, C; Morteau, O; Han, D S; Balfour Sartor, R

1998-01-01

153

Constitutive non-inducible expression of the Arabidopsis thaliana Nia 2 gene in two nitrate reductase mutants of Nicotiana Plumbaginifolia  

Microsoft Academic Search

We have isolated a haploid cell line of N. plumbaginifolia, hNP 588, that is constitutive and not inducible for nitrate reductase. Nitrate reductase mutants were isolated from hNP 588 protoplasts upon UV irradiation. Two of these nitrate reductase-deficient cell lines, nia 3 and nia 25, neither of which contained any detectable nitrate reductase activity, were selected for complementation studies. A

Claudia Kaye; Nigel M. Crawford; Russell L. Malmberg

1997-01-01

154

Constitutive expression of IL-18 and IL-18R in differentiated IEC-6 cells: effect of TNF-alpha and IFN-gamma treatment.  

PubMed

The multifunctional cytokine interleukin-18 (IL-18) is an important mediator in intestinal inflammatory processes. The aim of this study was to evaluate the constitutive expression of IL-18 and its receptors (IL-18Ralpha and IL-18Rbeta) in intestinal epithelial cells (IEC) stimulated by tumor necrosis factor-alpha (TNF-alpha) and interferon-gamma (IFN-gamma). In addition, cellular proliferation and evaluation of brush border enzymes as differentiation markers were studied. Nontransformed rat intestinal epithelial IEC-6 cells were grown on an extracellular matrix (ECM) in medium with or without TNF-alpha, IFN-gamma, or a combination of both. Gene expression of IL-18, its receptors and apoptotic markers was evaluated using real-time PCR. Expression of IL-18Ralpha protein was demonstrated by flow cytometry and Western blot. Enzymatic activities of brush border enzymes and caspase-1 were determined. The constitutive expression of IL-18, IL-18Ralpha and IL-18Rbeta mRNAs and proteins were detected in IEC-6 cells. The biologically active form of IL-18 was released in response to TNF-alpha and IFN-gamma treatment. Exogenous IL-18 had no effect on cellular proliferation, brush border enzyme activities, and gene expression of apoptotic markers. However, the addition of IL-18 stimulated production and release of the chemokine IL-8. These data suggest that IEC-6 cells may be not only a source of IL-18 but also a target for its action. PMID:18547159

Kolinska, Jirina; Lisa, Vera; Clark, Jessica A; Kozakova, Hana; Zakostelecka, Marie; Khailova, Ludmila; Sinkora, Marek; Kitanovicova, Andrea; Dvorak, Bohuslav

2008-05-01

155

Constitutive expression of the embryonic stem cell marker OCT4 in bovine somatic donor cells influences blastocysts rate and quality after nucleus transfer.  

PubMed

Nuclear transfer (NT) is associated with epigenetic reprogramming of donor cells. Expression of certain genes in these cells might facilitate their expression in the NT embryo. This research was aimed to investigate the effect of constitutive expression of OCT4 in bovine somatic cells used for NT on the developmental potential of derived cloned embryos as well as in the expression of pluripotency markers in the Day-7 resulting embryos. Cloned blastocysts were generated from five cell lines that expressed OCT4. Pools of blastocysts were screened to detect OCT4, SOX2, and NANOG by qPCR. In vitro-fertilized time-matched blastocysts were used as controls. The development potential was assessed on the basis of blastocysts rate; grading and total cell counts at Day 7. OCT4 expression in the cell lines positively correlates with blastocysts rate (r?=?0.92; p?=?0.02), number of grade I blastocysts (r?=?0.96; p?=?0.01), and total cell number (r?=?0.98; p?=?0.002). The high expression of OCT4 in the cell line did not improve the final outcome of cloning. Somatic expression of OCT4 lead to increased expression of OCT4 and SOX2 in cloned grade I blastocysts; however, there was a bigger variability in OCT4 and SOX2 (p?=?0.03; p?=?0.02) expression in the embryos generated from cells expressing highest levels of OCT4. Probably the higher variability in OCT4 expression in cloned embryos is due to incorrect reprogramming and incapability of the oocyte to correct for higher OCT4 levels. For that reason, we concluded that OCT4 expression in somatic cells is not a good prognosis marker for selecting cell lines. PMID:23846396

Rodríguez-Alvarez, Lleretny; Manriquez, Jose; Velasquez, Alejandra; Castro, Fidel Ovidio

2013-07-12

156

Constitutive G s activation using a single-construct tetracycline-inducible expression system in embryonic stem cells and mice  

Microsoft Academic Search

Introduction  The controlled expression of many genes, including G-protein coupled receptors (GPCRs), is important for delineating gene\\u000a functions in complex model systems. Binary systems for inducible regulation of transgene expression are widely used in mice.\\u000a One system is the tTA\\/TRE expression system, composed of a tetracycline-dependent DNA binding factor and a separate tetracycline\\u000a operon. However, the requirement for two separate transgenes

Edward C Hsiao; Trieu D Nguyen; Jennifer K Ng; Mark J Scott; Wei Chun Chang; Hengameh Zahed; Bruce R Conklin

2011-01-01

157

Transcriptome Atlases of Mouse Brain Reveals Differential Expression Across Brain Regions and Genetic Backgrounds  

PubMed Central

Mouse models play a crucial role in the study of human behavioral traits and diseases. Variation of gene expression in brain may play a critical role in behavioral phenotypes, and thus it is of great importance to understand regulation of transcription in mouse brain. In this study, we analyzed the role of two important factors influencing steady-state transcriptional variation in mouse brain. First we considered the effect of assessing whole brain vs. discrete regions of the brain. Second, we investigated the genetic basis of strain effects on gene expression. We examined the transcriptome of three brain regions using Affymetrix expression arrays: whole brain, forebrain, and hindbrain in adult mice from two common inbred strains (C57BL/6J vs. NOD/ShiLtJ) with eight replicates for each brain region and strain combination. We observed significant differences between the transcriptomes of forebrain and hindbrain. In contrast, the transcriptomes of whole brain and forebrain were very similar. Using 4.3 million single-nucleotide polymorphisms identified through whole-genome sequencing of C57BL/6J and NOD/ShiLtJ strains, we investigated the relationship between strain effect in gene expression and DNA sequence similarity. We found that cis-regulatory effects play an important role in gene expression differences between strains and that the cis-regulatory elements are more often located in 5? and/or 3? transcript boundaries, with no apparent preference on either 5? or 3? ends.

Sun, Wei; Lee, Seunggeun; Zhabotynsky, Vasyl; Zou, Fei; Wright, Fred A.; Crowley, James J.; Yun, Zaining; Buus, Ryan J.; Miller, Darla R.; Wang, Jeremy; McMillan, Leonard; Pardo-Manuel de Villena, Fernando; Sullivan, Patrick F.

2012-01-01

158

Degradation of Transcription Factor Rfx5 during the Inhibition of Both Constitutive and Interferon ?-Inducible Major Histocompatibility Complex Class I Expression in Chlamydia-Infected Cells  

PubMed Central

We have previously shown that the obligate intracellular pathogen chlamydia can suppress interferon (IFN)-?–inducible major histocompatibility complex (MHC) class II expression in infected cells by degrading upstream stimulation factor (USF)-1. We now report that chlamydia can also inhibit both constitutive and IFN-?–inducible MHC class I expression in the infected cells. The inhibition of MHC class I molecule expression correlates well with degradation of RFX5, an essential downstream transcription factor required for both the constitutive and IFN-?–inducible MHC class I expression. We further demonstrate that a lactacystin-sensitive proteasome-like activity identified in chlamydia-infected cell cytosolic fraction can degrade both USF-1 and RFX5. This proteasome-like activity is dependent on chlamydial but not host protein synthesis. Host preexisting proteasomes may not be required for the unique proteasome-like activity. These observations suggest that chlamydia-secreted factors may directly participate in the proteasome-like activity. Efforts to identify the chlamydial factors are underway. These findings provide novel information on the molecular mechanisms of chlamydial evasion of host immune recognition.

Zhong, Guangming; Liu, Li; Fan, Tao; Fan, Peiyi; Ji, Hezhao

2000-01-01

159

Transcription of the constitutively expressed yeast enolase gene ENO1 is mediated by positive and negative cis-acting regulatory sequences.  

PubMed Central

There are two enolase genes, ENO1 and ENO2, per haploid yeast genome. Expression of the ENO1 gene is quantitatively similar in cells grown on glucose or gluconeogenic carbon sources. In contrast, ENO2 expression is induced more than 20-fold in cells grown on glucose as the carbon source. cis-Acting regulatory sequences were mapped within the 5'-flanking region of the constitutively expressed yeast enolase gene ENO1. A complex positive regulatory region was located 445 base pairs (bp) upstream from the transcriptional initiation site which was required for ENO1 expression in cells grown on glycolytic or gluconeogenic carbon sources. A negative regulatory region was located 160 bp upstream from the transcriptional initiation site. Sequences required for the function of this negative regulatory element were mapped to a 38-bp region. Deletion of all or a portion of these latter sequences permitted glucose-dependent induction of ENO1 expression that was quantitatively similar to that of the glucose-inducible ENO2 gene. The negative regulatory element therefore prevents glucose-dependent induction of the ENO1 gene. Hybrid 5'-flanking regions were constructed which contained the upstream regulatory sequences of one enolase gene fused at a site upstream from the TATAAA box in the other enolase gene. Analysis of the expression of enolase genes containing these hybrid 5'-flanking region showed that the positive regulatory regions of ENO1 and ENO2 were functionally similar, as were the regions extending from the TATAAA boxes to the initiation codons. Based on these studies, we conclude that the negative regulatory element plays the critical role in maintaining the constitutive expression of the ENO1 structural gene in cells grown on glucose or gluconeogenic carbon sources. Images

Cohen, R; Yokoi, T; Holland, J P; Pepper, A E; Holland, M J

1987-01-01

160

PROTEIN EXPRESSION AND SECRETION BY TRICHODERMA REESEI UNDER LOW ENDOGENOUS PROTEIN BACKGROUND  

Technology Transfer Automated Retrieval System (TEKTRAN)

Trichoderma reesei (Hypocrea jecorina) is one of the most commonly used fungi for the manufacturing of industrial enzyme products. The fungus is capable of secreting proteins in levels up to 100 grams per liter. A number of homologous and heterologous proteins have been successfully over-expressed...

161

On the nature of facultative and constitutive CAM: environmental and developmental control of CAM expression during early growth of Clusia, Kalanchöe, and Opuntia.  

PubMed

The capacity to induce crassulacean acid metabolism developmentally (constitutive CAM) and to up-regulate CAM expression in response to drought stress (facultative CAM) was studied in whole shoots of seven species by measuring net CO(2) gas exchange for up to 120 day-night cycles during early growth. In Clusia rosea, CAM was largely induced developmentally. Well-watered seedlings began their life cycle as C(3) plants and developed net dark CO(2) fixation indicative of CAM after the initiation of the fourth leaf pair following the cotyledons. Thereafter, CAM activity increased progressively and drought stress led to only small additional, reversible increases in dark CO(2) fixation. In contrast, CAM expression was overwhelmingly under environmental control in seedlings and mature plants of Clusia pratensis. C(3)-type CO(2) exchange was maintained under well-watered conditions, but upon drought stress, CO(2) exchange shifted, in a fully reversible manner, to a CAM-type pattern. Clusia minor showed CO(2) exchange reponses intermediate to those of C. rosea and C. pratensis. Clusia cretosa operated in the C(3) mode at all times. Notably, reversible stress-induced increases of dark CO(2) fixation were also observed during the developmental progression to pronounced CAM in young Kalanchoë daigremontiana and Kalanchoë pinnata, two species considered constitutive CAM species. Drought-induced up-regulation of CAM was even detected in young cladodes of a cactus, Opuntia ficus-indica, an archetypal constitutive CAM species. Evidently, the defining characteristics of constitutive and facultative CAM are shared, to variable degrees, by all CAM species. PMID:18440928

Winter, Klaus; Garcia, Milton; Holtum, Joseph A M

2008-04-24

162

Constitutional Socialism in Yugoslavia  

Microsoft Academic Search

The new constitution recently inaugurated in Yugoslavia expresses the profound political and economic changes which have been taking place during the course of the last decade in the country and which are still under way. The beginning of the changes commenced as far back as in 1950 with the law on management of economic enterprises and other organizations under state

Ivan Maksimovi

1965-01-01

163

Background Gene Expression in Rat Kidney: Influence of Strain, Gender, and Diet  

Microsoft Academic Search

In order to gain better insight into factors (strain, gender, and diet) influencing background variability in kidney gene expres- sion, we examined the transcriptomes of male and female Crl: CD(SD)IGSBR (Sprague-Dawley (SD)) and CDF(Fischer 344)\\/ CrlBR rats maintained for 19 days on three different diets (ad libitum (AL), diet restriction—75% of AL, and casein-based phytoestrogen-free diet). Kidney RNA was analyzed

Shawn D. Seidel; Shao-Ching Hung; H. Lynn Kan; B. Bhaskar Gollapudi

2006-01-01

164

Constitutive expression and enzymatic activity of Tan protein in brain and epidermis of Ceratitis capitata and of Drosophila melanogaster wild-type and tan mutants.  

PubMed

The present report shows a partial biochemical characterization and life cycle expression of N-?-alanyldopamine hydrolase (Tan protein) in Ceratitis capitata and Drosophila melanogaster. This enzyme catalyzes the hydrolysis of N-?-alanyldopamine (NBAD), the main tanning precursor of insect brown cuticles. It also plays an important role in the metabolism of brain neurotransmitters, recycling dopamine and histamine. In contrast to NBAD-synthase, Tan is expressed constitutively in epidermis and does not respond directly to microbial challenge. Immunodetection experiments showed the novel localization of NBAD-hydrolase in the embryo central neural system and in different regions of the adult brain, in addition to optic lobes. We sequenced and characterized Drosophila mutants taną and tanł. The latter appears to be a mutant with normal expression in neural tissue but weak one in epidermis. PMID:21571070

Pérez, M M; Sabio, G; Badaracco, A; Quesada-Allué, L A

2011-05-07

165

Chemokine expression during mouse hepatitis virus-induced encephalitis: Contributions of the spike and background genes  

Microsoft Academic Search

Infection of mice with mouse hepatitis virus (MHV) strain JHM (RJHM) induces lethal encephalitis, with high macrophage and\\u000a neutrophil, but minimal T-cell, infiltration into the brain when compared to the neuroattenuated strain RA59. To determine\\u000a if chemokine expression corresponds with the cellular infiltrate, chemokine protein and RNA levels from the brains of infected\\u000a mice were quantified. RJHM-infected mice had lower

Erin P. Scott; Patrick J. Branigan; Alfred M. Del Vecchio; Susan R. Weiss

2008-01-01

166

Physiological effects of constitutive expression of Oilseed Rape Mosaic Tobamovirus (ORMV) movement protein in Arabidopsis thaliana  

Microsoft Academic Search

Movement proteins (MPs) are non-cell autonomous viral-encoded proteins that assist viruses in their cell-to-cell movement. The MP encoded by Tobamoviruses is the best characterized example among MPs of non-tubule-inducing plant RNA viruses. The MP of Oilseed Rape Mosaic Tobamovirus (ORMV) was transgenically expressed in Arabidopsis thaliana, ecotype RLD, under the expression of the 35S promoter from Cauliflower Mosaic Virus. Transgenic lines

Carmen Mansilla; Isabel Aguilar; David Martínez-Herrera; Flora Sánchez; Fernando Ponz

2006-01-01

167

Human eosinophils constitutively express multiple Th1, Th2, and immunoregulatory cytokines that are secreted rapidly and differentially  

PubMed Central

Eosinophils are innate immune leukocytes implicated in the initiation and maintenance of type 2 immune responses, including asthma and allergy. The ability to store and rapidly secrete preformed cytokines distinguishes eosinophils from most lymphocytes, which must synthesize cytokine proteins prior to secretion and may be a factor in the apparent Th2 bias of eosinophils. Multiple studies confirm that human eosinophils from atopic or hypereosinophilic donors can secrete over 30 cytokines with a varying and often opposing immune-polarizing potential. However, it remains unclear whether all of these cytokines are constitutively preformed and available for rapid secretion from eosinophils in the circulation of healthy individuals or are restricted to eosinophils from atopic donors. Likewise, the relative concentrations of cytokines stored within eosinophils have not been studied. Here, we demonstrate that human blood eosinophils are not singularly outfitted with Th2-associated cytokines but rather, constitutively store a cache of cytokines with nominal Th1, Th2, and regulatory capacities, including IL-4, IL-13, IL-6, IL-10, IL-12, IFN-?, and TNF-?. We demonstrate further rapid and differential release of each cytokine in response to specific stimuli. As agonists, strong Th1 and inflammatory cytokines elicited release of Th2-promoting IL-4 but not Th1-inducing IL-12. Moreover, a large quantity of IFN-? was secreted in response to Th1, Th2, and inflammatory stimuli. Delineations of the multifarious nature of preformed eosinophil cytokines and the varied stimulus-dependent profiles of rapid cytokine secretion provide insights into the functions of human eosinophils in mediating inflammation and initiation of specific immunity.

Spencer, Lisa A.; Szela, Craig T.; Perez, Sandra A. C.; Kirchhoffer, Casey L.; Neves, Josiane S.; Radke, Amy L.; Weller, Peter F.

2009-01-01

168

The transcription factors Sp1, Sp3, and AP-2 are required for constitutive matrix metalloproteinase-2 gene expression in astroglioma cells.  

PubMed

Matrix metalloproteinases (MMPs) are zinc-dependent endopeptidases that contribute to pathological conditions associated with angiogenesis and tumor invasion. MMP-2 is highly expressed in human astroglioma cells, and contributes to the invasiveness of these cells. The human MMP-2 promoter contains potential cis-acting regulatory elements including cAMP response element-binding protein, AP-1, AP-2, PEA3, C/EBP, and Sp1. Deletion and site-directed mutagenesis analysis of the MMP-2 promoter demonstrates that the Sp1 site at -91 to -84 base pairs and the AP-2 site at -61 to -53 base pairs are critical for constitutive activity of this gene in invasive astroglioma cell lines. Electrophoretic gel shift analysis demonstrates binding of specific DNA-protein complexes to the Sp1 and AP-2 sites: Sp1 and Sp3 bind to the Sp1 site, while the AP-2 transcription factor binds the AP-2 element. Co-transfection expression experiments in Drosophilia SL2 cells lacking endogenous Sp factors demonstrate that Sp1 and Sp3 function as activators of the MMP-2 promoter and synergize for enhanced MMP-2 activation. Overexpression of AP-2 in AP-2-deficient HepG2 cells enhances MMP-2 promoter activation. These findings document the functional importance of Sp1, Sp3, and AP-2 in regulating constitutive expression of MMP-2. Delineation of MMP-2 regulation may have implications for development of new therapeutic strategies to arrest glioma invasion. PMID:10506168

Qin, H; Sun, Y; Benveniste, E N

1999-10-01

169

Analysis of the expression from Rhizobium meliloti fix-promoters in other Rhizobium backgrounds.  

PubMed

Using translational fusions to lacZ, we have measured expression from the promoters of Rhizobium meliloti regulatory genes, nifA and fixK, and structural genes, nifH and fixA, in other fast-growing rhizobia whose nitrogen fixation regulation is less known. Neither nifA nor fixK promoters were activated under both free-living microaerobic and symbiotic conditions, except in R. tropici, where clear symbiotic activation of either nifA or fixK expression could be observed. Both nifH and fixA promoters showed strong heterologous activation during symbiosis and weak activation under free-living nitrogen starvation conditions. Only when the nifH promoter was in R. tropici and R. leguminosarum bv. phaseoli, was clear induction observed in the microaerobic free-living state. Deletion analysis of these promoters suggested that a NifA binding site (UAS) was needed for full heterologous activation of nifHp, either in microaerobiosis or symbiosis. In contrast, the UAS region seemed to be unnecessary for fixA activation. However, a region containing a potential integration host factor (IHF) binding site was observed to be needed for complete heterologous symbiotic induction from fixAp. The moderate induction observed in nitrogen-free medium only required the sigma 54 holoenzyme recognition sequence; this may be indicative of the existence of non-specific activation by NtrC-like proteins. Our results suggest possible common and different features in the control mechanisms of the nitrogen fixation gene expression among Rhizobium species. PMID:8012569

Cebolla, A; Ruiz-Berraquero, F; Palomares, A J

1994-03-01

170

Improvement of ethanol production from D-lactic acid by constitutive expression of lactate transporter Jen1p in Saccharomyces cerevisiae.  

PubMed

To improve ethanol production from D-lactate, Jen1p, a monocarboxylate-proton symporter, was constitutively expressed in Saccharomyces cerevisiae NAM34-4C. The mutant produced 2.4 g/L of ethanol, approximately 2.4 times higher than that of the wild-type strain. A monocarboxylate/proton symporter gene (JEN1) null mutant was also constructed. It produced 0.19 g/L of ethanol, 5 times lower than that of the wild-type strain. PMID:23649240

Wakamatsu, Makoto; Tomitaka, Masataka; Tani, Tatsunori; Taguchi, Hisataka; Kida, Kenji; Akamatsu, Takashi

2013-05-07

171

Theileria-mediated constitutive expression of the casein kinase II-alpha subunit in bovine lymphoblastoid cells.  

PubMed

Theileria-infected cells are induced to undergo a transformation that is reversible, since their proliferation is inhibited after elimination of the schizonts by the theilericidal drug buparvaquone. The molecular mechanisms of the transformation remain unknown. The experiments described in the present report deal with the role of casein kinase (CK) II, a serine/threonine protein kinase, in the permanent proliferation of the parasitized cells and show that the CK II-alpha subunit is expressed in both T. annulata- and T. parva-infected cells and that its expression is closely related to the presence of the parasites in the host-cell cytoplasm. Thus, elimination of the schizonts by buparvaquone leads to the inhibition of CK II-alpha subunit mRNA expression without affecting the expression of actin. Cells treated with 5,6-dichloro-1-beta-D-ribofuranosylbenzimidazole (DRB) are inhibited in a dose-dependent manner from under-going DNA synthesis as measured by [3H]-thymidine incorporation and from expressing CK II. Furthermore, a host-cell-specific CK II-alpha antisense inhibits DNA synthesis in a dose-dependent manner. In the present study, 6 microM antisense reduced [3H]-thymidine incorporation by Theileria-infected bovine cells to about 50%. Using a primer derived from T. parva CK II, we detected a parasite-specific CK II mRNA in T. parva-infected cell lines. Interestingly. DRB also inhibited the expression of the parasite-specific CK II. However, to date we have not detected a target sequence for this primer in T. annulata schizonts. PMID:9211502

Shayan, P; Ahmed, J S

1997-01-01

172

Constitutive roles for inducible genes: evidence for the alteration in expression of the inducible hsp70 gene in Antarctic notothenioid fishes.  

PubMed

Previous research on the Antarctic notothenioid fish Trematomus bernacchii demonstrated the loss of the heat shock response (HSR), a classical cellular defense mechanism against thermal stress, characterized by the rapid synthesis of heat shock proteins (Hsps). In the current study, we examined potential mechanisms for the apparent loss of the HSR in Antarctic notothenioids and, in addition, compared expression patterns of two genes from the 70-kDa Hsp family (hsc71 and hsp70) in tissues from T. bernacchii to expression patterns in tissues of two closely related temperate notothenioid fishes from New Zealand, Bovichtus variegatus and Notothenia angustata. The results showed that transcript for both the constitutive and inducible genes in the Hsp70 gene family were expressed in detectable levels in all three species. However, only the cold-temperate New Zealand fishes displayed the ability to upregulate the inducible transcript, hsp70. Although hsp70 was present in detectable levels in several tissues of the Antarctic notothen T. bernacchii, in vitro thermal stresses failed to produce a significant increase in mRNA levels. In all species, the expression of the constitutive transcript hsc71 was variable and nonresponsive to temperature increases, even at temperatures as high as 10 degrees C above the ecologically relevant range for the species under study. Field-collected tissues from T. bernacchii (sampled immediately after capture) indicated that hsp70 mRNA was expressed at high levels in field-acclimatized fishes. Thus upregulation of molecular chaperones suggested that low-temperature stress may be significantly denaturing to cellular proteins in Antarctic fish, an observation that was supported by elevated levels of ubiquitin-conjugated protein. PMID:15117724

Place, Sean P; Zippay, Mackenzie L; Hofmann, Gretchen E

2004-04-29

173

Biochemical and Morphological Consequences of Human ?-Synuclein Expression in a Mouse ?-Synuclein Null Background  

PubMed Central

A consensus about the functions of human wild-type or mutated ?-synuclein (?SYN) is lacking. Both forms of ?SYN are implicated in Parkinson’s disease, whereas the wild-type form is implicated in substance abuse. Interactions with other cellular proteins and organelles may meditate its functions. We developed a series of congenic mouse lines containing various allele doses or combinations of the human wild type ?SYN (hw?SYN) or a doubly mutated (A30P*A53T) ?SYN (hm2?SYN) in a C57Bl/6J line spontaneously deleted in mouse ?SYN (C57BL/6JOla). Both transgenes had a functional role in the nigrostriatal system, demonstrated by significant elevations in striatal catecholamines, metabolites, and the enzyme tyrosine hydroxylase compared to null-mice without a transgene. Consequences occurred when the transgenes were expressed at a fraction of the endogenous level. Hemizygous congenic mice did not exhibit any change in the number or size of dopaminergic neurons in the ventral midbrain at nine months of age. Human ?SYN was predominantly located in neuronal cell bodies, neurites, synapses, and in intraneuronal/intraneuritic aggregates. The hm2?SYN transgene resulted in more aggregates and dystrophic neurites than did the hw5 transgene. The hw?SYN transgene resulted in higher expression of two striatal proteins, synaptogamin 7 and UCHL1, compared to the levels of the hm2?SYN transgene. These observations suggest that mutations in ?SYN may impair specific functional domains, leaving others intact. These lines may also be useful for exploring interactions between h?SYN and environmental or genetic risk factors in dopamine-related disorders using a mouse model.

Prasad, Kavita; Tarasewicz, Elizabeth; Strickland, Pamela A. Ohman; O'Neill, Michael; Mitchell, Stephen N.; Merchant, Kalpana; Tep, Samnang; Hilton, Kathryn; Datwani, Akash; Buttini, Manuel; Mueller-Steiner, Sarah; Richfield, Eric K.

2011-01-01

174

Biochemical and morphological consequences of human ?-synuclein expression in a mouse ?-synuclein null background.  

PubMed

A consensus about the functions of human wild-type or mutated ?-synuclein (?SYN) is lacking. Both forms of ?SYN are implicated in Parkinson's disease, whereas the wild-type form is implicated in substance abuse. Interactions with other cellular proteins and organelles may meditate its functions. We developed a series of congenic mouse lines containing various allele doses or combinations of the human wild-type ?SYN (hw?SYN) or a doubly mutated (A30P*A53T) ?SYN (hm(2) ?SYN) in a C57Bl/6J line spontaneously deleted in mouse ?SYN (C57BL/6JOla). Both transgenes had a functional role in the nigrostriatal system, demonstrated by significant elevations in striatal catecholamines, metabolites and the enzyme tyrosine hydroxylase compared with null-mice without a transgene. Consequences occurred when the transgenes were expressed at a fraction of the endogenous level. Hemizygous congenic mice did not exhibit any change in the number or size of dopaminergic neurons in the ventral midbrain at 9 months of age. Human ?SYN was predominantly located in neuronal cell bodies, neurites, synapses, and in intraneuronal/intraneuritic aggregates. The hm(2) ?SYN transgene resulted in more aggregates and dystrophic neurites than did the hw5 transgene. The hw?SYN transgene resulted in higher expression of two striatal proteins, synaptogamin 7 and UCHL1, compared with the levels of the hm(2) ?SYN transgene. These observations suggest that mutations in ?SYN may impair specific functional domains, leaving others intact. These lines may be useful for exploring interactions between h?SYN and environmental or genetic risk factors in dopamine-related disorders using a mouse model. PMID:21272100

Prasad, Kavita; Tarasewicz, Elizabeth; Strickland, Pamela A Ohman; O'Neill, Michael; Mitchell, Stephen N; Merchant, Kalpana; Tep, Samnang; Hilton, Kathryn; Datwani, Akash; Buttini, Manuel; Mueller-Steiner, Sarah; Richfield, Eric K

2011-01-28

175

Dysmegakaryopoiesis of FPD/AML pedigrees with constitutional RUNX1 mutations is linked to myosin II deregulated expression.  

PubMed

FPD/AML is a familial platelet disorder characterized by platelet defects, predisposition to acute myelogenous leukemia (AML) and germ-line heterozygous RUNX1 alterations. Here we studied the in vitro megakaryopoiesis of 3 FPD/AML pedigrees. A 60% to 80% decrease in the output of megakaryocytes (MKs) from CD34(+) was observed. MK ploidy level was low and mature MKs displayed a major defect in proplatelet formation. To explain these defects, we focused on myosin II expression as RUNX1 has been shown to regulate MYL9 and MYH10 in an inverse way. In FPD/AML MKs, expression of MYL9 and MYH9 was decreased, whereas MYH10 expression was increased and the MYH10 protein was still present in the cytoplasm of mature MKs. Myosin II activity inhibition by blebbistatin rescued the ploidy defect of FPD/AML MKs. Finally, we demonstrate that MYH9 is a direct target of RUNX1 by chromatin immunoprecipitation and luciferase assays and we identified new RUNX1 binding sites in the MYL9 promoter region. Together, these results demonstrate that the defects in megakaryopoiesis observed in FPD/AML are, in part, related to a deregulation of myosin IIA and IIB expression leading to both a defect in ploidization and proplatelet formation. PMID:22898599

Bluteau, Dominique; Glembotsky, Ana C; Raimbault, Anna; Balayn, Nathalie; Gilles, Laure; Rameau, Philippe; Nurden, Paquita; Alessi, Marie Christine; Debili, Najet; Vainchenker, William; Heller, Paula G; Favier, Remi; Raslova, Hana

2012-08-16

176

Constitutive gene expression profile segregates toxicity in locally advanced breast cancer patients treated with high-dose hyperfractionated radical radiotherapy  

Microsoft Academic Search

Breast cancer patients show a wide variation in normal tissue reactions after radiotherapy. The individual sensitivity to x-rays limits the efficiency of the therapy. Prediction of individual sensitivity to radiotherapy could help to select the radiation protocol and to improve treatment results. The aim of this study was to assess the relationship between gene expression profiles of ex vivo un-irradiated

Luis Alberto Henríquez Hernández; Pedro Carlos Lara; Beatriz Pinar; Elisa Bordón; Carlos Rodríguez Gallego; Cristina Bilbao; Leandro Pérez; Amílcar Flores Morales

2009-01-01

177

hsp23 and hsp26 exhibit distinct spatial and temporal patterns of constitutive expression in Drosophila adults.  

PubMed

To determine differences in the patterns of expression of Drosophila small heat shock proteins (shsp) during normal development in the absence of stress, proteins obtained from head, thorax and gonads of young (0-12 h, 3 days), middle-aged (3-6 days) and 15- to 20-day-old adult flies were separated on SDS-PAGE gels and blotted with monoclonal antibodies against hsp23 and hsp26. hsp23 was found in the heads and gonads of young males and females. In contrast, the maximum expression of hsp26 was seen in gonads of young flies, and it was only lightly detected in the brain. The expression of both proteins decreased as flies aged. This age-related decrease was particularly striking for hsp23 in females. The immunoblot results obtained were complemented by immunostaining of thin parasagittal sections of whole fly bodies. Hsp23 was found to be expressed in the brain, thoracic ganglion, fat body and gonads of young (0-12 h) males and females. On the other hand, hsp26 was essentially detected in ovaries and testes of these young flies. The analysis of the tissue expression of both proteins demonstrate that each shsp has a distinct cellular localization. In the central nervous system, hsp23 and hsp26 were present in the neurocytes of the brain and the thoracic ganglion. In addition, hsp23 (but not hsp26) was also detected in the central neuropile of these two organs. In testis, hsp26 was localized in the cytoplasm of spermatocytes and, probably, in the spermatid bundles. In contrast, hsp23 was detected at the periphery of cells (membranes).(ABSTRACT TRUNCATED AT 250 WORDS) PMID:8482013

Marin, R; Valet, J P; Tanguay, R M

1993-01-01

178

An inducible 70 kDa-class heat shock protein is constitutively expressed during early development and diapause in the annual killifish Austrofundulus limnaeus  

PubMed Central

The annual killifish Austrofundulus limnaeus inhabits ephemeral ponds in regions of northern South America, where they survive the periodic drying of their habitat as diapausing embryos. These diapausing embryos are highly resistant to a number of environmental insults such as high temperature, dehydration, anoxia, and increased salinity. Molecular chaperones are known to play a role in stabilizing protein structure and function during events of cellular stress. Relative levels of heat shock protein (Hsp)70 were measured in developing and diapausing embryos of A. limnaeus using quantitative Western blots. An inducible or embryo-specific form of Hsp70 is expressed during embryonic development in A. limnaeus and is elevated during diapause II in this species. Constitutive expression of Hsp70 during development may afford these embryos protection from environmental stresses during development more quickly than relying on the induction of a classic heat shock response.

Podrabsky, Jason E.; Somero, George N.

2007-01-01

179

Behavior of a cloned murine interferon alpha/beta receptor expressed in homospecific or heterospecific background.  

PubMed Central

A murine interferon (IFN) alpha/beta receptor was cloned from the IFN-sensitive L1210 cell line on the basis of its homology with the human receptor. A combination of methods that includes the screening of random-primed and oligo(dT)-primed cDNA libraries and polymerase chain reactions with a single-side specificity was used. At the amino acid level, the murine IFN-alpha/beta shows 46% identity with its human counterpart. Both human WISH cells presenting a low sensitivity to mouse IFN and a murine L1210 mutant subline that does not express the receptor have been stably transfected with the murine IFN-alpha/beta receptor. Whereas transfected human cells became sensitive to a limited number of mouse IFN-alpha/beta subtypes, the transfected murine L1210 mutant was found to be fully complemented and became sensitive to all mouse IFN-alpha/beta subtypes tested, including those that were not active on transfected human cells. These results strongly suggest that the receptor described here is implicated in the mediation of the activities of all murine IFN-alpha/beta subtypes. Images

Uze, G; Lutfalla, G; Bandu, M T; Proudhon, D; Mogensen, K E

1992-01-01

180

Inducible and constitutive transcription factors in the mammalian nervous system: control of gene expression by Jun, Fos and Krox, and CREB/ATF proteins.  

PubMed

This article reviews findings up to the end of 1997 about the inducible transcription factors (ITFs) c-Jun, JunB, JunD, c-Fos, FosB, Fra-1, Fra-2, Krox-20 (Egr-2) and Krox-24 (NGFI-A, Egr-1, Zif268); and the constitutive transcription factors (CTFs) CREB, CREM, ATF-2 and SRF as they pertain to gene expression in the mammalian nervous system. In the first part we consider basic facts about the expression and activity of these transcription factors: the organization of the encoding genes and their promoters, the second messenger cascades converging on their regulatory promoter sites, the control of their transcription, the binding to dimeric partners and to specific DNA sequences, their trans-activation potential, and their posttranslational modifications. In the second part we describe the expression and possible roles of these transcription factors in neural tissue: in the quiescent brain, during pre- and postnatal development, following sensory stimulation, nerve transection (axotomy), neurodegeneration and apoptosis, hypoxia-ischemia, generalized and limbic seizures, long-term potentiation and learning, drug dependence and withdrawal, and following stimulation by neurotransmitters, hormones and neurotrophins. We also describe their expression and possible roles in glial cells. Finally, we discuss the relevance of their expression for nervous system functioning under normal and patho-physiological conditions. PMID:9858769

Herdegen, T; Leah, J D

1998-12-01

181

Vesicular glutamate transporter 3-expressing nonserotonergic projection neurons constitute a subregion in the rat midbrain raphe nuclei.  

PubMed

We previously reported that about 80% of vesicular glutamate transporter 3 (VGLUT3)-positive cells displayed immunoreactivity for serotonin, but the others were negative in the rat midbrain raphe nuclei, such as the dorsal (DR) and median raphe nuclei (MnR). In the present study, to investigate the precise distribution of VGLUT3-expressing nonserotonergic neurons in the DR and MnR, we performed double fluorescence in situ hybridization for VGLUT3 and tryptophan hydroxylase 2 (TPH2). According to the distribution of VGLUT3 and TPH2 mRNA signals, we divided the DR into six subregions. In the MnR and the rostral (DRr), ventral (DRV), and caudal (DRc) parts of the DR, VGLUT3 and TPH2 mRNA signals were frequently colocalized (about 80%). In the lateral wings (DRL) and core region of the dorsal part of the DR (DRDC), TPH2-producing neurons were predominantly distributed, and about 94% of TPH2-producing neurons were negative for VGLUT3 mRNA. Notably, in the shell region of the dorsal part of the DR (DRDSh), VGLUT3 mRNA signals were abundantly detected, and about 75% of VGLUT3-expressing neurons were negative for TPH2 mRNA. We then examined the projection of VGLUT3-expressing nonserotonergic neurons in the DRDSh by anterograde and retrograde labeling after chemical depletion of serotonergic neurons. The projection was observed in various brain regions such as the ventral tegmental area, substantia nigra pars compacta, hypothalamic nuclei, and preoptic area. These results suggest that VGLUT3-expressing nonserotonergic neurons in the midbrain raphe nuclei are preferentially distributed in the DRDSh and modulate many brain regions with the neurotransmitter glutamate via ascending axons. PMID:20034056

Hioki, Hiroyuki; Nakamura, Hisashi; Ma, Yun-Fei; Konno, Michiteru; Hayakawa, Takashi; Nakamura, Kouichi C; Fujiyama, Fumino; Kaneko, Takeshi

2010-03-01

182

Constitutive expression of Vitis vinifera thaumatin-like protein after in vitro selection and its role in anthracnose resistance  

Microsoft Academic Search

Anthracnose-resistant grapevine (Vitis vinifera L. cv. Chardonnay) plants were regenerated from embryogenic cultures that had been subjected to in vitro selection with culture filtrate of Elsinoe ampelina (de Bary) Shear. Three secreted proteins differentially expressed by in vitro-selected embryogenic cultures and regenerated plants were identified. An 8-kDa protein was identified as a lipid-transfer protein (LTP) by N-terminal amino acid sequence

Subramanian JayasankarA; Zhijian Li; Dennis J. Gray

2003-01-01

183

Expression of a constitutive form of calcium/calmodulin dependent protein kinase II leads to arrest of the cell cycle in G2.  

PubMed Central

Calcium/calmodulin dependent protein kinase II (CaMKII) is a multifunctional serine/threonine protein kinase. We have created a calcium/calmodulin independent form of this enzyme by truncation. Expression of this enzyme fragment in a rabbit reticulocyte lysate yields a constitutive enzyme with specific activity similar to the activated native enzyme. We have established mammalian cell lines that transiently express this constitutive enzyme using the glucocorticoid-inducible mouse mammary tumor virus long terminal repeat. The transient increase in kinase activity results in a complete cessation of cell cycle progression. This block develops as a consequence of a specific arrest of the cell cycle in G2. During the block, increases in histone H1 kinase activity present in p13 beads or anti-cdc2 immunoprecipitates are seen in parallel with the accumulation of cells at G2, arguing that the arrest is not due to a failure to activate cdc2 as a histone H1 kinase. These results suggest that other changes in serine/threonine protein phosphorylation besides those involved in activation of cdc2 as a histone H1 kinase may be necessary for proper G2-M transition. Images

Planas-Silva, M D; Means, A R

1992-01-01

184

Constitutive Smad signaling and Smad-dependent collagen gene expression in mouse embryonic fibroblasts lacking peroxisome proliferator-activated receptor-{gamma}  

SciTech Connect

Transforming growth factor-{beta} (TGF-{beta}), a potent inducer of collagen synthesis, is implicated in pathological fibrosis. Peroxisome proliferator-activated receptor-{gamma} (PPAR-{gamma}) is a nuclear hormone receptor that regulates adipogenesis and numerous other biological processes. Here, we demonstrate that collagen gene expression was markedly elevated in mouse embryonic fibroblasts (MEFs) lacking PPAR-{gamma} compared to heterozygous control MEFs. Treatment with the PPAR-{gamma} ligand 15d-PGJ{sub 2} failed to down-regulate collagen gene expression in PPAR-{gamma} null MEFs, whereas reconstitution of these cells with ectopic PPAR-{gamma} resulted in their normalization. Compared to control MEFs, PPAR-{gamma} null MEFs displayed elevated levels of the Type I TGF-{beta} receptor (T{beta}RI), and secreted more TGF-{beta}1 into the media. Furthermore, PPAR-{gamma} null MEFs showed constitutive phosphorylation of cellular Smad2 and Smad3, even in the absence of exogenous TGF-{beta}, which was abrogated by the ALK5 inhibitor SB431542. Constitutive Smad2/3 phosphorylation in PPAR-{gamma} null MEFs was associated with Smad3 binding to its cognate DNA recognition sequences, and interaction with coactivator p300 previously implicated in TGF-{beta} responses. Taken together, these results indicate that loss of PPAR-{gamma} in MEFs is associated with upregulation of collagen synthesis, and activation of intracellular Smad signal transduction, due, at least in part, to autocrine TGF-{beta} stimulation.

Ghosh, Asish K [Northwestern University Feinberg School of Medicine, Division of Rheumatology, 240 East Huron Street, Chicago, IL 60611 (United States)], E-mail: a-ghosh2@northwestern.edu; Wei, Jun; Wu, Minghua [Northwestern University Feinberg School of Medicine, Division of Rheumatology, 240 East Huron Street, Chicago, IL 60611 (United States); Varga, John [Northwestern University Feinberg School of Medicine, Division of Rheumatology, 240 East Huron Street, Chicago, IL 60611 (United States)], E-mail: j-varga@northwestern.edu

2008-09-19

185

Enhancement of stress tolerance in transgenic tobacco plants constitutively expressing AtIpk2?, an inositol polyphosphate 6-/3-kinase from Arabidopsis thaliana  

PubMed Central

Inositol phosphates (IPs) and their turnover products have been implicated to play important roles in stress signaling in eukaryotic cells. In higher plants genes encoding inositol polyphosphate kinases have been identified previously, but their physiological functions have not been fully resolved. Here we expressed Arabidopsis inositol polyphosphate 6-/3-kinase (AtIpk2?) in two heterologous systems, i.e. the yeast Saccharomycescerevisiae and in tobacco (Nicotiana tabacum), and tested the effect on abiotic stress tolerance. Expression of AtIpk2? rescued the salt-, osmotic- and temperature-sensitive growth defects of a yeast mutant strain (arg82?) that lacks inositol polyphosphate multikinase activity encoded by the ARG82/IPK2 gene. Transgenic tobacco plants constitutively expressing AtIpk2? under the control of the Cauliflower Mosaic Virus 35S promoter were generated and found to exhibit improved tolerance to diverse abiotic stresses when compared to wild type plants. Expression patterns of various stress responsive genes were enhanced, and the activities of anti-oxidative enzymes were elevated in transgenic plants, suggesting a possible involvement of AtIpk2? in plant stress responses. Electronic supplementary material The online version of this article (doi:10.1007/s11103-007-9267-3) contains supplementary material, which is available to authorized users.

Yang, Lei; Tang, Renjie; Zhu, Jinqi; Liu, Hua; Mueller-Roeber, Bernd; Xia, Huijun

2007-01-01

186

Fc?RIIa, Not Fc?RIIb, Is Constitutively and Functionally Expressed on Skin-Derived Human Mast Cells1  

PubMed Central

The expression of Fc?R by human skin-derived mast cells of the MCTC type was determined in the current study. Expression of mRNA was analyzed with microarray gene chips and RT-PCR; protein by Western blotting and flow cytometry; function by release of ?-hexosaminidase, PGD2, leukotriene C4 (LTC4), IL-5, IL-6, IL-13, GM-CSF, and TNF-?. Fc?RIIa was consistently detected along with Fc?RI at the mRNA and protein levels; Fc?RIIc was sometimes detected only by RT-PCR; but Fc?RIIb, Fc?RI, and Fc?RIII mRNA and protein were not detected. Fc?RIIa-specific mAb caused skin MCTC cells to degranulate secrete PGD2, LTC4, GM-CSF, IL-5, IL-6, IL-13, and TNF-? in a dose-dependent fashion. Fc?RI-specific mAb caused similar amounts of each mediator to be released with the exception of LTC4, which was not released by this agonist. Simultaneous but independent cross-linking of Fc?RI and Fc?RIIa did not substantially alter mediator release above or below levels observed with each agent alone. Skin MCTC cells sensitized with dust-mite-specific IgE and IgG, when coaggregated by Der p2, exhibited enhanced degranulation compared with sensitization with either IgE or IgG alone. These results extend the known capabilities of human skin mast cells to respond to IgG as well as IgE-mediated signals.

Zhao, Wei; Kepley, Christopher L.; Morel, Penelope A.; Okumoto, Lawrence M.; Fukuoka, Yoshihiro; Schwartz, Lawrence B.

2007-01-01

187

Constitutive Expression of the Cytochrome P450 EthABCD Monooxygenase System Enables Degradation of Synthetic Dialkyl Ethers in Aquincola tertiaricarbonis L108  

PubMed Central

In Rhodococcus ruber IFP 2001, Rhodococcus zopfii IFP 2005, and Gordonia sp. strain IFP 2009, the cytochrome P450 monooxygenase EthABCD catalyzes hydroxylation of methoxy and ethoxy residues in the fuel oxygenates methyl tert-butyl ether (MTBE), ethyl tert-butyl ether (ETBE), and tert-amyl methyl ether (TAME). The expression of the IS3-type transposase-flanked eth genes is ETBE dependent and controlled by the regulator EthR (C. Malandain et al., FEMS Microbiol. Ecol. 72:289–296, 2010). In contrast, we demonstrated by reverse transcription-quantitative PCR (RT-qPCR) that the betaproteobacterium Aquincola tertiaricarbonis L108, which possesses the ethABCD genes but lacks ethR, constitutively expresses the P450 system at high levels even when growing on nonether substrates, such as glucose. The mutant strain A. tertiaricarbonis L10, which is unable to degrade dialkyl ethers, resulted from a transposition event mediated by a rolling-circle IS91-type element flanking the eth gene cluster in the wild-type strain L108. The constitutive expression of Eth monooxygenase is likely initiated by the housekeeping sigma factor ?70, as indicated by the presence in strain L108 of characteristic ?10 and ?35 binding sites upstream of ethA which are lacking in strain IFP 2001. This enables efficient degradation of diethyl ether, diisopropyl ether, MTBE, ETBE, TAME, and tert-amyl ethyl ether (TAEE) without any lag phase in strain L108. However, ethers with larger residues, n-hexyl methyl ether, tetrahydrofuran, and alkyl aryl ethers, were not attacked by the Eth system at significant rates in resting-cell experiments, indicating that the residue in the ether molecule which is not hydroxylated also contributes to the determination of substrate specificity.

Schuster, Judith; Purswani, Jessica; Breuer, Uta; Pozo, Clementina; Harms, Hauke; Muller, Roland H.

2013-01-01

188

Constitutive expression of the cytochrome P450 EthABCD monooxygenase system enables degradation of synthetic dialkyl ethers in Aquincola tertiaricarbonis L108.  

PubMed

In Rhodococcus ruber IFP 2001, Rhodococcus zopfii IFP 2005, and Gordonia sp. strain IFP 2009, the cytochrome P450 monooxygenase EthABCD catalyzes hydroxylation of methoxy and ethoxy residues in the fuel oxygenates methyl tert-butyl ether (MTBE), ethyl tert-butyl ether (ETBE), and tert-amyl methyl ether (TAME). The expression of the IS3-type transposase-flanked eth genes is ETBE dependent and controlled by the regulator EthR (C. Malandain et al., FEMS Microbiol. Ecol. 72:289-296, 2010). In contrast, we demonstrated by reverse transcription-quantitative PCR (RT-qPCR) that the betaproteobacterium Aquincola tertiaricarbonis L108, which possesses the ethABCD genes but lacks ethR, constitutively expresses the P450 system at high levels even when growing on nonether substrates, such as glucose. The mutant strain A. tertiaricarbonis L10, which is unable to degrade dialkyl ethers, resulted from a transposition event mediated by a rolling-circle IS91-type element flanking the eth gene cluster in the wild-type strain L108. The constitutive expression of Eth monooxygenase is likely initiated by the housekeeping sigma factor ?(70), as indicated by the presence in strain L108 of characteristic -10 and -35 binding sites upstream of ethA which are lacking in strain IFP 2001. This enables efficient degradation of diethyl ether, diisopropyl ether, MTBE, ETBE, TAME, and tert-amyl ethyl ether (TAEE) without any lag phase in strain L108. However, ethers with larger residues, n-hexyl methyl ether, tetrahydrofuran, and alkyl aryl ethers, were not attacked by the Eth system at significant rates in resting-cell experiments, indicating that the residue in the ether molecule which is not hydroxylated also contributes to the determination of substrate specificity. PMID:23354715

Schuster, Judith; Purswani, Jessica; Breuer, Uta; Pozo, Clementina; Harms, Hauke; Müller, Roland H; Rohwerder, Thore

2013-01-25

189

The Constitution of Civil Society  

Microsoft Academic Search

This Article . . .sketches how the free expression, freedom of religion, and substantive due process provisions of the U.S. Constitution have been interpreted to define and protect families, religious institutions, non-political associations, and political parties. I have organized the discussion by topics rather than by institutions. The next section examines the ways in which constitutional law defines civil society's

Mark V. Tushnet

2000-01-01

190

Constitutive expression of the SOS response in recA718 mutants of Escherichia coli requires amplification of RecA718 protein.  

PubMed Central

In recA718 lexA+ strains of Escherichia coli, induction of the SOS response requires DNA damage. This implies that RecA718 protein, like RecA+ protein, must be converted, by a process initiated by the damage, to an activated form (RecA) to promote cleavage of LexA, the cellular repressor of SOS genes. However, when LexA repressor activity was abolished by a lexA-defective mutation [lexA(Def)], strains carrying the recA718 gene (but not recA+) showed strong SOS mutator activity and were able to undergo stable DNA replication in the absence of DNA damage (two SOS functions known to require RecA activity even when cleavage of LexA is not necessary). lambda lysogens of recA718 lexA(Def) strains exhibited mass induction of prophage, indicative of constitutive ability to cleave lambda repressor. When the cloned recA718 allele was present in a lexA+ strain on a plasmid, SOS mutator activity and beta-galactosidase synthesis under LexA control were expressed in proportion to the plasmid copy number. We conclude that RecA718 is capable of becoming activated without DNA damage for cleavage of LexA and lambda repressor, but only if it is amplified above its base-line level in lexA+ strains. At amplified levels, RecA718 was also constitutively activated for its roles in SOS mutagenesis and stable DNA replication. The nucleotide sequence of recA718 reveals two base substitutions relative to the recA+ sequence. We propose that the first allows the protein to become activated constitutively, whereas the second partially suppresses this capability. Images

McCall, J O; Witkin, E M; Kogoma, T; Roegner-Maniscalco, V

1987-01-01

191

Genome-wide expression analysis upon constitutive activation of the HacA bZIP transcription factor in Aspergillus niger reveals a coordinated cellular response to counteract ER stress  

PubMed Central

Background HacA/Xbp1 is a conserved bZIP transcription factor in eukaryotic cells which regulates gene expression in response to various forms of secretion stress and as part of secretory cell differentiation. In the present study, we replaced the endogenous hacA gene of an Aspergillus niger strain with a gene encoding a constitutively active form of the HacA transcription factor (HacACA). The impact of constitutive HacA activity during exponential growth was explored in bioreactor controlled cultures using transcriptomic analysis to identify affected genes and processes. Results Transcription profiles for the wild-type strain (HacAWT) and the HacACA strain were obtained using Affymetrix GeneChip analysis of three replicate batch cultures of each strain. In addition to the well known HacA targets such as the ER resident foldases and chaperones, GO enrichment analysis revealed up-regulation of genes involved in protein glycosylation, phospholipid biosynthesis, intracellular protein transport, exocytosis and protein complex assembly in the HacACA mutant. Biological processes over-represented in the down-regulated genes include those belonging to central metabolic pathways, translation and transcription. A remarkable transcriptional response in the HacACA strain was the down-regulation of the AmyR transcription factor and its target genes. Conclusions The results indicate that the constitutive activation of the HacA leads to a coordinated regulation of the folding and secretion capacity of the cell, but with consequences on growth and fungal physiology to reduce secretion stress.

2012-01-01

192

Recruitment of CREB1 and Histone Deacetylase 2 (HDAC2) to the Mouse Ltbp-1 Promoter Regulates its Constitutive Expression in a Dioxin Receptor-dependent Manner  

PubMed Central

Latent TGF?-binding protein 1 (LTBP-1) is a key regulator of TGF? targeting and activation in the extracellular matrix. LTBP-1 is recognized as a major docking molecule to localize, and possibly to activate, TGF? in the extracellular matrix. Despite this relevant function, the molecular mechanisms regulating Ltbp-1 transcription remain largely unknown. Previous results from our laboratory revealed that mouse embryonic fibroblasts (MEF) lacking dioxin receptor (AhR) had increased Ltbp-1 mRNA expression and elevated TGF? activity, suggesting that AhR repressed Ltbp-1 transcription. Here, we have cloned the mouse Ltbp-1 gene promoter and analysed its mechanism of transcriptional repression by AhR. Reporter gene assays, AhR over-expression and site-directed mutagenesis showed that basal Ltbp-1 transcription is AhR-dependent. Chromatin immunoprecipitation (ChIP) and RNA interference (RNAi) revealed that AhR regulates Ltbp-1 transcription by a mechanism involving recruitment of co-activators such as CREB1 and co-repressors such as HDAC2 to the Ltbp-1 promoter. In AhR-expressing (AhR+/+) MEF cells, the recruitment of HDAC1, 2 and 4 correlated with decreased K8H4 acetylation and impaired binding of pCREBSer133 to the Ltbp-1 promoter, likely maintaining a constitutive repressed state. AhR?/? MEF cells had the opposite pattern of HDACs and pCREB1Ser133 binding to Ltbp-1 promoter, and therefore, over-expressed Ltbp-1 mRNA. In agreement, siRNA for HDAC2 increased Ltbp-1 expression and K8H4 acetylation in AhR+/+ but not in AhR?/? MEF cells. We suggest that HDAC2 binding keeps Ltbp-1 promoter repressed in AhR+/+ MEF cells, whereas in AhR-null MEF cells the absence of HDAC2 and the binding of pCREBSer133 allow Ltbp-1 transcription. Thus, epigenetics can contribute to constitutive Ltbp-1 repression by a mechanism requiring AhR activity.

Gomez-Duran, Aurea; Ballestar, Esteban; Carvajal-Gonzalez, Jose M.; Marlowe, Jennifer L.; Puga, Alvaro; Esteller, Manel; Fernandez-Salguero, Pedro M.

2010-01-01

193

Selection for low or high primary dormancy in Lolium rigidum Gaud seeds results in constitutive differences in stress protein expression and peroxidase activity  

PubMed Central

Seed dormancy in wild Lolium rigidum Gaud (annual ryegrass) populations is highly variable and not well characterized at the biochemical level. To identify some of the determinants of dormancy level in these seeds, the proteomes of subpopulations selected for low and high levels of primary dormancy were compared by two-dimensional polyacrylamide gel electrophoresis of extracts from mature, dry seeds. High-dormancy seeds showed higher expression of small heat shock proteins, enolase, and glyoxalase I than the low-dormancy seeds. The functional relevance of these differences in protein expression was confirmed by the fact that high-dormancy seeds were more tolerant to high temperatures imposed at imbibition and had consistently higher glyoxalase I activity over 0–42?d dark stratification. Higher expression of a putative glutathione peroxidase in low-dormancy seeds was not accompanied by higher activity, but these seeds had a slightly more oxidized glutathione pool and higher total peroxidase activity. Overall, these biochemical and physiological differences suggest that L. rigidum seeds selected for low dormancy are more prepared for rapid germination via peroxidase-mediated cell wall weakening, whilst seeds selected for high dormancy are constitutively prepared to survive environmental stresses, even in the absence of stress during seed development.

Goggin, Danica E.; Powles, Stephen B.; Steadman, Kathryn J.

2011-01-01

194

Expression of the protein chaperone, clusterin, in spinal cord cells constitutively and following cellular stress, and upregulation by treatment with Hsp90 inhibitor.  

PubMed

Clusterin, a protein chaperone found at high levels in physiological fluids, is expressed in nervous tissue and upregulated in several neurological diseases. To assess relevance to amyotrophic lateral sclerosis (ALS) and other motor neuron disorders, clusterin expression was evaluated using long-term dissociated cultures of murine spinal cord and SOD1(G93A) transgenic mice, a model of familial ALS. Motor neurons and astrocytes constitutively expressed nuclear and cytoplasmic forms of clusterin, and secreted clusterin accumulated in culture media. Although clusterin can be stress inducible, heat shock failed to increase levels in these neural cell compartments despite robust upregulation of stress-inducible Hsp70 (HspA1) in non-neuronal cells. In common with HSPs, clusterin was upregulated by treatment with the Hsp90 inhibitor, geldanamycin, and thus could contribute to the neuroprotection previously identified for such compounds in disease models. Clusterin expression was not altered in cultured motor neurons expressing SOD1(G93A) by gene transfer or in presymptomatic SOD1(G93A) transgenic mice; however, clusterin immunolabeling was weakly increased in lumbar spinal cord of overtly symptomatic mice. More striking, mutant SOD1 inclusions, a pathological hallmark, were strongly labeled by anti-clusterin. Since secreted, as well as intracellular, mutant SOD1 contributes to toxicity, the extracellular chaperoning property of clusterin could be important for folding and clearance of SOD1 and other misfolded proteins in the extracellular space. Evaluation of chaperone-based therapies should include evaluation of clusterin as well as HSPs, using experimental models that replicate the control mechanisms operant in the cells and tissue of interest. PMID:23595219

Zinkie, Samantha; Gentil, Benoit J; Minotti, Sandra; Durham, Heather D

2013-04-19

195

The nuclear receptors pregnane X receptor and constitutive androstane receptor contribute to the impact of fipronil on hepatic gene expression linked to thyroid hormone metabolism.  

PubMed

Fipronil is described as a thyroid disruptor in rat. Based on the hypothesis that this results from a perturbation of hepatic thyroid hormone metabolism, our goal was to investigate the pathways involved in fipronil-induced liver gene expression regulations. First, we performed a microarray screening in the liver of rats treated with fipronil or vehicle. Fipronil treatment led to the upregulation of several genes involved in the metabolism of xenobiotics, including the cytochrome P450 Cyp2b1, Cyp2b2 and Cyp3a1, the carboxylesterases Ces2 and Ces6, the phase II enzymes Ugt1a1, Sult1b1 and Gsta2, and the membrane transporters Abcc2, Abcc3, Abcg5, Abcg8, Slco1a1 and Slco1a4. Based on a large overlap with the target genes of constitutive androstane receptor (CAR) and pregnane X receptor (PXR), we postulated that these two nuclear receptors are involved in mediating the effects of fipronil on liver gene expression in rodents. We controlled that liver gene expression changes induced by fipronil were generally reproduced in mice, and then studied the effects of fipronil in wild-type, CAR- and PXR-deficient mice. For most of the genes studied, the gene expression modulations were abolished in the liver of PXR-deficient mice and were reduced in the liver of CAR-deficient mice. However, CAR and PXR activation in mouse liver was not associated with a marked increase of thyroid hormone clearance, as observed in rat. Nevertheless, our data clearly indicate that PXR and CAR are key modulators of the hepatic gene expression profile following fipronil treatment which, in rats, may contribute to increase thyroid hormone clearance. PMID:23962444

Roques, Béatrice B; Leghait, Julien; Lacroix, Marlčne Z; Lasserre, Frédéric; Pineau, Thierry; Viguié, Catherine; Martin, Pascal G P

2013-08-17

196

Acetaminophen modulates p-glycoprotein functional expression at the blood-brain barrier by a constitutive androstane receptor-dependent mechanism.  

PubMed

Effective pharmacologic treatment of pain with opioids requires that these drugs attain efficacious concentrations in the central nervous system (CNS). A primary determinant of CNS drug permeation is P-glycoprotein (P-gp), an endogenous blood-brain barrier (BBB) efflux transporter that is involved in brain-to-blood transport of opioid analgesics (i.e., morphine). Recently, the nuclear receptor constitutive androstane receptor (CAR) has been identified as a regulator of P-gp functional expression at the BBB. This is critical to pharmacotherapy of pain/inflammation, as patients are often administered acetaminophen (APAP), a CAR-activating ligand, in conjunction with an opioid. Our objective was to investigate, in vivo, the role of CAR in regulation of P-gp at the BBB. Following APAP treatment, P-gp protein expression was increased up to 1.4-1.6-fold in a concentration-dependent manner. Additionally, APAP increased P-gp transport of BODIPY-verapamil in freshly isolated rat brain capillaries. This APAP-induced increase in P-gp expression and activity was attenuated in the presence of CAR pathway inhibitor okadaic acid or transcriptional inhibitor actinomycin D, suggesting P-gp regulation is CAR-dependent. Furthermore, morphine brain accumulation was enhanced by P-gp inhibitors in APAP-treated animals, suggesting P-gp-mediated transport. A warm-water (50°C) tail-flick assay revealed a significant decrease in morphine analgesia in animals treated with morphine 3 or 6 hours after APAP treatment, as compared with animals treated concurrently. Taken together, our data imply that inclusion of APAP in a pain treatment regimen activates CAR at the BBB and increases P-gp functional expression, a clinically significant drug-drug interaction that modulates opioid analgesic efficacy. PMID:24019224

Slosky, Lauren M; Thompson, Brandon J; Sanchez-Covarrubias, Lucy; Zhang, Yifeng; Laracuente, Mei-Li; Vanderah, Todd W; Ronaldson, Patrick T; Davis, Thomas P

2013-09-09

197

CD40 ligand is constitutively expressed in a subset of T cell lymphomas and on the microenvironmental reactive T cells of follicular lymphomas and Hodgkin's disease.  

PubMed Central

Although CD40 has been extensively studied in B- and T-cell non-Hodgkin's lymphomas (NHLs)/leukemias, and more recently in Hodgkin's disease (HD), little is known about the expression of its ligand (CD40L) in lymphoproliferative disorders other than T-cell NHLs/leukemias. A series of 121 lymphoma/leukemia samples, including 35 cases of HD, 34 T-cell and 39 B-cells NHLs, 2 cases of adult T-cell leukemia/lymphoma, and 11 cases of T-cell acute lymphoblastic leukemia, were evaluated for CD40L expression by immunostaining of frozen tissue sections and flow cytometry with the anti-CD40L monoclonal antibody M90. CD40L was constitutively expressed by neoplastic cells in 15 of 36 (42%) T-cell NHLs/adult T-cell leukemia/lymphomas, almost invariably those displaying the CD4+/CD8- phenotype, whereas no CD40L-expressing tumor cells could be found in B-cell NHL and HD. Among T-cell acute lymphoblastic leukemias, CD40L was detected only on 2 cases displaying a stem-cell-like phenotype. In follicular B-cell lymphomas a large number of CD40L-expressing CD3+/CD4+ T lymphocytes were found admixed with tumor cells within the neoplastic follicles and in their surrounding areas. In the nonfollicular B-cell lymphomas, CD40L-positive CD3+/CD4+ T lymphocytes were few or absent. In all HD subtypes other than the nodular lymphocytic predominance, CD40L-expressing CD3+/CD4+ T lymphocytes were numerous in the HD-involved areas and were mainly located in close proximity to the Reed-Sternberg cells. Our data indicate that in human lymphomas CD40L is preferentially expressed by a restricted subset of T-cell lymphomas, mostly with CD4 immunophenotype. Finally, we have provided morphological evidence that CD40L may play an important role in the cell contact-dependent interaction of tumor B-cells (CD40+) within the neoplastic follicles or Reed-Sternberg cells (CD40+) in HD-involved areas and the microenvironmental CD3+/CD4+/CD40L+ T lymphocytes. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 6 Figure 7

Carbone, A.; Gloghini, A.; Gruss, H. J.; Pinto, A.

1995-01-01

198

Interleukin-22 binding protein (IL-22BP) is constitutively expressed by a subset of conventional dendritic cells and is strongly induced by retinoic acid.  

PubMed

Interleukin-22 (IL-22) is mainly produced at barrier surfaces by T cells and innate lymphoid cells and is crucial to maintain epithelial integrity. However, dysregulated IL-22 action leads to deleterious inflammation and is involved in diseases such as psoriasis, intestinal inflammation, and cancer. IL-22 binding protein (IL-22BP) is a soluble inhibitory IL-22 receptor and may represent a crucial regulator of IL-22. We show both in rats and mice that, in the steady state, the main source of IL-22BP is constituted by a subset of conventional dendritic cells (DCs) in lymphoid and non-lymphoid tissues. In mouse intestine, IL-22BP was specifically expressed in lamina propria CD103(+)CD11b(+) DC. In humans, IL-22BP was expressed in immature monocyte-derived DC and strongly induced by retinoic acid but dramatically reduced upon maturation. Our data suggest that a subset of immature DCs may actively participate in the regulation of IL-22 activity in the gut by producing high levels of IL-22BP.Mucosal Immunology advance online publication 8 May 2013; doi:10.1038/mi.2013.28. PMID:23653115

Martin, J Cj; Bériou, G; Heslan, M; Chauvin, C; Utriainen, L; Aumeunier, A; Scott, C L; Mowat, A; Cerovic, V; Houston, S A; Leboeuf, M; Hubert, F X; Hémont, C; Merad, M; Milling, S; Josien, R

2013-05-08

199

Quantitative expression profiling of G-protein-coupled receptors (GPCRs) in metastatic melanoma: the constitutively active orphan GPCR GPR18 as novel drug target.  

PubMed

G-protein-coupled receptors (GPCRs) have been implicated in the tumorigenesis and metastasis of human cancers and are considered amongst the most desirable targets for drug development. Utilizing a robust quantitative PCR array, we quantified expression of 94 human GPCRs, including 75 orphan GPCRs and 19 chemokine receptors, and 36 chemokine ligands, in 40 melanoma metastases from different individuals and benign nevi. Inter-metastatic site comparison revealed that orphan GPR174 and CCL28 are statistically significantly overexpressed in subcutaneous metastases, while P2RY5 is overexpressed in brain metastases. Comparison between metastases (all three metastatic sites) and benign nevi revealed that 16 genes, including six orphan receptors (GPR18, GPR34, GPR119, GPR160, GPR183 and P2RY10) and chemokine receptors CCR5, CXCR4, and CXCR6, were statistically significantly differentially expressed. Subsequent functional experiments in yeast and melanoma cells indicate that GPR18, the most abundantly overexpressed orphan GPCR in all melanoma metastases, is constitutively active and inhibits apoptosis, indicating an important role for GPR18 in tumor cell survival. GPR18 and five other orphan GPCRs with yet unknown biological function may be considered potential novel anticancer targets in metastatic melanoma. PMID:20880198

Qin, Y; Verdegaal, E M E; Siderius, M; Bebelman, J P; Smit, M J; Leurs, R; Willemze, R; Tensen, C P; Osanto, S

2010-10-21

200

Reduced expression of IL-12 p35 by SJL/J macrophages responding to Theiler's virus infection is associated with constitutive activation of IRF-3  

SciTech Connect

Macrophages responding to viral infections may contribute to autoimmune demyelinating diseases (ADD). Macrophages from ADD-susceptible SJL/J mice responding to Theiler's Virus (TMEV) infection, the TLR7 agonist loxoribine, or the TLR4 agonist-LPS expressed less IL-12 p35 but more IL-12/23 p40 and IFN-{beta} than macrophages from ADD-resistant B10.S mice. While expression of IRF-1 and -7 was similar between B10.S and SJL/J TMEV-infected macrophages, SJL/J but not B10.S macrophages exhibited constitutively active IRF-3. In contrast to overexpressed IRF-1, IRF-5, and IRF-7, which stimulated p35 promoter reporter activity, overexpressed IRF-3 repressed p35 promoter activity in response to TMEV infection, loxoribine, IFN-{gamma}/LPS, but not IFN-{gamma} alone. IRF-3 lessened but did not eliminate IRF-1-stimulated p35 promoter activity. Repression by IRF-3 required bp -172 to -122 of the p35 promoter. The data suggest that pre-activated IRF-3 is a major factor in the differences in IL-12 production between B10.S and SJL/J macrophages responding to TMEV.

Dahlberg, Angela [Department of Oral Biology and Nebraska Center for Virology, University of Nebraska Medical Center, 40th and Holdrege Sts., Lincoln, NE 68583-0740 (United States); Auble, Mark R. [Department of Oral Biology and Nebraska Center for Virology, University of Nebraska Medical Center, 40th and Holdrege Sts., Lincoln, NE 68583-0740 (United States); Petro, Thomas M. [Department of Oral Biology and Nebraska Center for Virology, University of Nebraska Medical Center, 40th and Holdrege Sts., Lincoln, NE 68583-0740 (United States)]. E-mail: tpetro@unmc.edu

2006-09-30

201

A constitutively expressed Myc-like gene involved in anthocyanin biosynthesis from Perilla frutescens: molecular characterization, heterologous expression in transgenic plants and transactivation in yeast cells  

Microsoft Academic Search

The coordinate expression of anthocyanin biosynthetic genes in leaves and stems of a red forma of Perilla frutescens is presumably controlled by regulatory gene(s). A Myc-like gene (Myc-rp) was isolated from a cDNA library prepared from the leaves of red P. frutescens, and its deduced amino acid sequence shows 64% identity with that of delila from snapdragon. The Myc-rp gene was

Zhi-Zhong Gong; Emiko Yamagishi; Mami Yamazaki; Kazuki Saito

1999-01-01

202

Reconstitution of human telomerase reverse transcriptase expression rescues colorectal carcinoma cells from in vitro senescence: evidence against immortality as a constitutive trait of tumor cells.  

PubMed

Although in vitro establishment of new colorectal carcinoma (CRC) cell lines is an infrequent event, we have observed that primary cultures of CRC can be repeatedly and reproducibly initiated following in vitro plating of tumor-derived epithelial cells. These cultures, however, usually display a short life span as they undergo a limited number of cell passages before entering a state of irreversible growth arrest. In this study, we show that short-lived CRC primary cultures lack constitutive telomerase activity and undergo a senescence process characterized by progressive telomere shortening. Moreover, transduction of these cells with a retroviral vector encoding human telomerase reverse transcriptase (hTERT) is sufficient to reconstitute telomerase activity and allow immortalization. Detailed molecular characterization of hTERT-immortalized CRC cell lines confirms their individual tumor origin by showing expression of colonic epithelial differentiation markers, such as cytokeratin-20 (CK20), full match with class I and class II human leukocyte antigen genotyping of autologous B-lymphoblastoid cells, and presence of somatic mutations in key cancer genes (KRAS2, APC) identical to those of the corresponding autologous original tumor tissues. Moreover, functional characterization of hTERT-immortalized CRC cell lines shows that they have a transformed phenotype, being able to form colonies in soft agar and tumors in severe combined immunodeficient mice. Most interestingly, immunohistochemical analysis of original tumor tissues indicates that short-lived CRC primary cultures, although hTERT-negative in vitro, derive from hTERT-positive tumors. Taken together, our data show that, in a least subset of CRC, biochemical pathways involved in maintenance of telomere length, such as telomerase, are not activated in a constitutive way in all tumor cells. PMID:15781646

Dalerba, Piero; Guiducci, Cristiana; Poliani, Pietro Luigi; Cifola, Ingrid; Parenza, Mariella; Frattini, Milo; Gallino, Gianfrancesco; Carnevali, Ileana; Di Giulio, Ilvia; Andreola, Salvatore; Lombardo, Claudia; Rivoltini, Licia; Schweighoffer, Tamás; Belli, Filiberto; Colombo, Mario P; Parmiani, Giorgio; Castelli, Chiara

2005-03-15

203

Constitutive expression of pregnancy-associated plasma protein-A in arterial smooth muscle reduces the vascular response to injury in vivo.  

PubMed

Pregnancy-associated plasma protein-A (PAPP-A) functions to increase local IGF-I bioactivity. In this study, we used transgenic mice that constitutively express human PAPP-A in arterial smooth muscle to test the hypothesis that overexpression of PAPP-A enhances vascular smooth muscle cell (SMC) response to IGF-I in vivo. PAPP-A transgenic (Tg) and wild-type (WT) mice underwent unilateral carotid ligation, a model of injury-induced SMC hyperplasia and neointimal formation. In both WT and PAPP-A Tg mice, endogenous PAPP-A mRNA expression showed peak elevation 5 days after carotid ligation. However, PAPP-A Tg mice had 70-75% less neointima than WT at 5 and 10 days postligation, with a significant reduction in occlusion of the ligated artery. WT and PAPP-A Tg mice had equivalent increases in medial area and vessel remodeling postligation. There was little change in medial area and no evidence of neointima in the contralateral carotid of WT or PAPP-A Tg mice. Both WT and PAPP-A Tg carotids exhibited signs of dedifferentiation of SMC, which precedes the increase in proliferation and migration that results in neointimal formation. However, the number of proliferating cells in the media and neointima of the ligated PAPP-A Tg artery was reduced by 90% on day 5 postsurgery compared with WT. This decrease was associated with a significant decrease in an in vivo marker of IGF-I bioactivity and reduced IGF-I-stimulated receptor phosphorylation ex vivo. These data suggest differential effects of chronic (transgenic) and transient (endogenous) PAPP-A expression on neointimal formation following vascular injury that may be due in part to the differential impact on IGF-I signaling. PMID:23169786

Bale, Laurie K; Resch, Zachary T; Harstad, Sara L; Overgaard, Michael T; Conover, Cheryl A

2012-11-20

204

Expression of a Constitutively Activated Plasma Membrane H+-ATPase Alters Plant Development and Increases Salt Tolerance1[C][OA  

PubMed Central

The plasma membrane proton pump ATPase (H+-ATPase) plays a major role in the activation of ion and nutrient transport and has been suggested to be involved in several physiological processes, such as cell expansion and salt tolerance. Its activity is regulated by a C-terminal autoinhibitory domain that can be displaced by phosphorylation and the binding of regulatory 14-3-3 proteins, resulting in an activated enzyme. To better understand the physiological consequence of this activation, we have analyzed transgenic tobacco (Nicotiana tabacum) plants expressing either wild-type plasma membrane H+-ATPase4 (wtPMA4) or a PMA4 mutant lacking the autoinhibitory domain (?PMA4), generating a constitutively activated enzyme. Plants showing 4-fold higher expression of wtPMA4 than untransformed plants did not display any unusual phenotype and their leaf and root external acidification rates were not modified, while their in vitro H+-ATPase activity was markedly increased. This indicates that, in vivo, H+-ATPase overexpression is compensated by down-regulation of H+-ATPase activity. In contrast, plants that expressed ?PMA4 were characterized by a lower apoplastic and external root pH, abnormal leaf inclination, and twisted stems, suggesting alterations in cell expansion. This was confirmed by in vitro leaf extension and curling assays. These data therefore strongly support a direct role of H+-ATPase in plant development. The ?PMA4 plants also displayed increased salt tolerance during germination and seedling growth, supporting the hypothesis that H+-ATPase is involved in salt tolerance.

Gevaudant, Frederic; Duby, Geoffrey; von Stedingk, Erik; Zhao, Rongmin; Morsomme, Pierre; Boutry, Marc

2007-01-01

205

Induction of CYP3A4 and MDR1 gene expression by baicalin, baicalein, chlorogenic acid, and ginsenoside Rf through constitutive androstane receptor- and pregnane X receptor-mediated pathways.  

PubMed

The herbal products baicalin, baicalein, chlorogenic acid, and ginsenoside Rf have multiple pharmacological effects and are extensively used in alternative and/or complementary therapies. The present study investigated whether baicalin, baicalein, chlorogenic acid, and ginsenoside Rf induced the expression of the cytochrome P450 3A4 (CYP3A4) and multi-drug resistance 1 (MDR1) genes through the pregnane X receptor and constitutive androstane receptor pathways. Real time PCR, western blotting, and a luminescent assay were used to assess the induction of gene expression and activity of CYP3A4 and MDR1 by the test compounds. The interactions of baicalein/chlorogenic acid/ginsenoside Rf with constitutive androstane receptor and pregnane X receptor were evaluated using luciferase reporter and gel shift assays. Baicalein induced the expression of CYP3A4 and MDR1 mRNA by activating pregnane X receptor and constitutive androstane receptor. Chlorogenic acid and ginsenoside Rf showed a relatively weak effect on CYP3A4 promoter activation only in HepG2 cells cotransfected with constitutive androstane receptor and demonstrated no effects on MDR1 via either the constitutive androstane receptor or pregnane X receptor pathway. Baicalin had no effect on either CYP3A4 or MDR1 gene expression. In conclusion, baicalein has the potential to up-regulate CYP3A4 and MDR1 through the direct activation of the constitutive androstane receptor and pregnane X receptor pathways. Chlorogenic acid and ginsenoside Rf only induced constitutive androstane receptor-mediated CYP3A4 expression. PMID:20580705

Li, Yue; Wang, Qi; Yao, Xiaomin; Li, Yan

2010-08-25

206

P 0Is Constitutively Expressed in the Rat Neural Crest and Embryonic Nerves and Is Negatively and Positively Regulated by Axons to Generate Non-Myelin-Forming and Myelin-Forming Schwann Cells, Respectively  

Microsoft Academic Search

We show that in the rat, the major gene of PNS myelin, P0, is expressed long before myelination in the neural crest, Schwann cell precursors, and embryonic Schwann cells irrespective of whether they will myelinate or not. This myelin-independent P0expression is constitutive and likely to serve as a specific marker for the Schwann cell lineage. The much higher P0expression accompanying

M.-J. Lee; A. Brennan; A. Blanchard; G. Zoidl; Z. Dong; A. Tabernero; C. Zoidl; M. A. R. Dent; K. R. Jessen; R. Mirsky

1997-01-01

207

Inhibition of Proteasome Activity Promotes the Correct Localization of Disease-Causing ?-Sarcoglycan Mutants in HEK-293 Cells Constitutively Expressing ?-, ?-, and ?-Sarcoglycan  

PubMed Central

Sarcoglycanopathies are progressive muscle-wasting disorders caused by genetic defects of four proteins, ?-, ?-, ?-, and ?-sarcoglycan, which are elements of a key transmembrane complex of striated muscle. The proper assembly of the sarcoglycan complex represents a critical issue of sarcoglycanopathies, as several mutations severely perturb tetramer formation. Misfolded proteins are generally degraded through the cell’s quality-control system; however, this can also lead to the removal of some functional polypeptides. To explore whether it is possible to rescue sarcoglycan mutants by preventing their degradation, we generated a heterologous cell system, based on human embryonic kidney (HEK) 293 cells, constitutively expressing three (?, ?, and ?) of the four sarcoglycans. In these ???-HEK cells, the lack of ?-sarcoglycan prevented complex formation and cell surface localization, wheras the presence of ?-sarcoglycan allowed maturation and targeting of the tetramer. As in muscles of sarcoglycanopathy patients, transfection of ???-HEK cells with disease-causing ?-sarcoglycan mutants led to dramatic reduction of the mutated proteins and the absence of the complex from the cell surface. Proteasomal inhibition reduced the degradation of mutants and facilitated the assembly and targeting of the sarcoglycan complex to the plasma membrane. These data provide important insights for the potential development of pharmacological therapies for sarcoglycanopathies.

Gastaldello, Stefano; D'Angelo, Simona; Franzoso, Susanna; Fanin, Marina; Angelini, Corrado; Betto, Romeo; Sandona, Dorianna

2008-01-01

208

Characterization and constitutive expression of an acidic mesophilic endo-1,4-?-D-xylanohydrolase with high thermotolerance and catalytic efficiency in Pichia pastoris.  

PubMed

A putative endo-1,4-?-D-xylanohydrolase gene xyl11 from Aspergillus niger, encoding a 188-residue xylanase of glycosyl hydrolase family 11, was constitutively expressed in Pichia pastoris. The recombinant Xyl11 exhibited optimal activity at pH 5.0 and 50 °C, and displayed more than 68 % of the maximum activity over the temperature range 35-65 °C and 33 % over the pH range 2.2-7.0. It maintained more than 40 % of the original activity after incubation at 90 °C (pH 5.0) for 10 min and more than 75 % of the original activity after incubation at pH 2.2-11.0 (room temperature) for 2 h. The specific activity, K m and V max of purified Xyl11 were 22,253 U mg(-1), 6.57 mg ml(-1) and 51,546.4 ?mol min(-1) mg(-1). It could degrade xylan to a series of xylooligosaccharides and no xylose was detected. The recombinant enzyme with high stability and catalytic efficiency could work over wide ranges of pH and temperature and thus has the potential for various industrial applications. PMID:23670313

Guo, Ning; Zheng, Jia; Tian, Jian; Wu, Lishuang; Zhou, Hongbo

2013-05-14

209

Constitutive Expression of Insulin Receptor Substrate (IRS)-1 Inhibits Myogenic Differentiation through Nuclear Exclusion of Foxo1 in L6 Myoblasts  

PubMed Central

Insulin-like growth factors (IGFs) are well known to play essential roles in enhancement of myogenic differentiation. In this report we showed that initial IGF-I signal activation but long-term IGF-1 signal termination are required for myogenic differentiation. L6 myoblast stably transfected with myc-epitope tagged insulin receptor substrate-1, myc-IRS-1 (L6-mIRS1) was unable to differentiate into myotubes, indicating that IRS-1 constitutive expression inhibited myogenesis. To elucidate the molecular mechanisms underlying myogenic inhibition, IGF-I signaling was examined. IGF-I treatment of control L6 cells for 18 h resulted in a marked suppression of IGF-I stimulated IRS-1 association with the p85 PI 3-kinase and suppression of activation of Akt that correlated with a down regulation of IRS-1 protein. L6-mIRS1 cells, in contrast, had sustained high levels of IRS-1 protein following 18 h of IGF-I treatment with persistent p85 PI 3-kinase association with IRS-1, Akt phosphorylation and phosphorylation of the downstream Akt substrate, Foxo1. Consistent with Foxo1 phosphorylation, Foxo1 protein was excluded from the nuclei in L6-mIRS1 cells, whereas Foxo1 was localized in the nuclei in control L6 cells during induction of differentiation. In addition, L6 cells stably expressing a dominant-interfering form of Foxo1, ?256Foxo1 (L6-?256Foxo1) were unable to differentiate into myotubes. Together, these data demonstrate that IGF-I regulation of Foxo1 nuclear localization is essential for the myogenic program in L6 cells but that persistent activation of IGF-1 signaling pathways results in a negative feedback to prevent myogenesis.

Hakuno, Fumihiko; Yamauchi, Yoko; Kaneko, Gen; Yoneyama, Yosuke; Nakae, Jun; Chida, Kazuhiro; Kadowaki, Tatsuhiko; Yamanouchi, Keitaro; Nishihara, Masugi; Takahashi, Shin-Ichiro

2011-01-01

210

Functional consequences of stably expressing a mutant calsequestrin (CASQ2D307H) in the CASQ2 null background  

PubMed Central

The role of calsequestrin (CASQ2) in cardiac sarcoplasmic reticulum (SR) calcium (Ca2+) transport has gained significant attention since point mutations in CASQ2 were reported to cause ventricular arrhythmia. In the present study, we have critically evaluated the functional consequences of expressing the CASQ2D307H mutant protein in the CASQ2 null mouse. We recently reported that the mutant CASQ2D307H protein can be stably expressed in CASQ2 null hearts, and it targets appropriately to the junctional SR (Kalyanasundaram A, Bal NC, Franzini-Armstrong C, Knollmann BC, Periasamy M. J Biol Chem 285: 3076–3083, 2010). In this study, we found that introduction of CASQ2D307H protein in the CASQ2 null background partially restored triadin 1 levels, which were decreased in the CASQ2 null mice. Despite twofold expression (relative to wild-type CASQ2), the mutant protein failed to increase SR Ca2+ load. We also found that the Ca2+ transient decays slower in the CASQ2 null and CASQ2D307H cells. CASQ2D307H myocytes, when rhythmically paced and challenged with isoproterenol, exhibit spontaneous Ca2+ waves similar to CASQ2 null myocytes; however, the stability of Ca2+ cycling was increased in the CASQ2D307H myocytes. In the presence of isoproterenol, Ca2+-transient amplitude in CASQ2D307H myocytes was significantly decreased, possibly indicating an inherent defect in Ca2+ buffering capacity and release from the mutant CASQ2 at high Ca2+ concentrations. We also observed polymorphic ventricular tachycardia in the CASQ2D307H mice, although lesser than in the CASQ2 null mice. These data suggest that CASQ2D307H point mutation may affect Ca2+ buffering capacity and Ca2+ release. We propose that poor interaction between CASQ2D307H and triadin 1 could affect ryanodine receptor 2 stability, thereby increasing susceptibility to delayed afterdepolarizations and triggered arrhythmic activity.

Kalyanasundaram, Anuradha; Viatchenko-Karpinski, Serge; Belevych, Andriy E.; Lacombe, Veronique A.; Hwang, Hyun Seok; Knollmann, Bjorn C.; Gyorke, Sandor

2012-01-01

211

Microplane constitutive model for porous isotropic rocks  

Microsoft Academic Search

The paper deals with constitutive modelling of contiguous rock located between rock joints. A fully explicit kinematically constrained microplane-type constitutive model for hardening and softening non-linear triaxial behaviour of isotropic porous rock is developed. The microplane framework, in which the constitutive relation is expressed in terms of stress and strain vectors rather than tensors, makes it possible to model various

Zdenk P. Baant; Goangseup Zi

2003-01-01

212

The Constitutional Amendment Process  

ERIC Educational Resources Information Center

|This article discusses the constitutional amendment process. Although the process is not described in great detail, Article V of the United States Constitution allows for and provides instruction on amending the Constitution. While the amendment process currently consists of six steps, the Constitution is nevertheless quite difficult to change.…

Chism, Kahlil

2005-01-01

213

The Constitution of Reasons  

Microsoft Academic Search

Cass Sunstein's book, The Partial Constitution, brings together a number of his constitutional law essays from the last ten years. During that time, Sunstein has argued, powerfully, for the unconstitutionality of regulatory constraints on access to abortion; for the constitutionality of and the need for regulation of violent pornography; for the constitutionality of limits on both campaign spending and congressional

Robin West

1994-01-01

214

America's Constitutional Narrative  

Microsoft Academic Search

America has always been a wonderfully diverse place, a country where billions of stories spanning centuries and continents converge under the rubric of a Constitution that unites them in an ongoing narrative of national self-creation. Rather than rehearse familiar debates over what our Constitution means, this essay explores what the Constitution does. It treats the Constitution as a verb a

Laurence H. Tribe

2012-01-01

215

The Constitution and The Other Constitution  

Microsoft Academic Search

In this article, Professor Michael Kent Curtis examines how laws that shape the distribution of wealth intersect with and affect popular sovereignty and free speech and press. He presents this discussion in the context of the effect of the Other Constitution on The Constitution. Professor Curtis begins by taking a close-up look at the current campaign finance system and the

Michael Kent Curtis

2002-01-01

216

Constitutive Activation of the G-Protein Subunit G[alpha]s within Forebrain Neurons Causes PKA-Dependent Alterations in Fear Conditioning and Cortical "Arc" mRNA Expression  

ERIC Educational Resources Information Center

|Memory formation requires cAMP signaling; thus, this cascade has been of great interest in the search for cognitive enhancers. Given that medications are administered long-term, we determined the effects of chronically increasing cAMP synthesis in the brain by expressing a constitutively active isoform of the G-protein subunit G[alpha]s…

Kelly, Michele P.; Cheung, York-Fong; Favilla, Christopher; Siegel, Steven J.; Kanes, Stephen J.; Houslay, Miles D.; Abel, Ted

2008-01-01

217

Individualized medicine, health medicine, and constitutional theory in Chinese medicine.  

PubMed

The patterns of modern science and changes in the medical model can result in the transformation of the current state of individualized and health medicines into being the primary trend in medical development. Chinese and Western medical systems are dissimilar in terms of value orientations, thinking style, and research directions because of their different historical and cultural backgrounds. Individualized treatment in modern medicine is mainly established based on individual genome information and the differences in mononucleotide polymorphisms. However, such treatment method is expensive, creates an uncertain genetic marker, and leads to different result interpretations, among other problems. The Chinese constitutional theory developed in the 1970s expresses the principle behind Chinese health medicine and individual treatment and provides the corresponding methods. The Chinese constitutional theory divides the constitution of the Chinese population into nine categories based on established classification criteria. It promotes the study of the relationship of each constitution to diseases and Chinese medicine preparation toward adjusting the constitution and preventing diseases. The theory also provides methods and tools for individualized treatment. Constitution identification shows the direction and provides the core technology for the evaluation of the health status. By combining the developments in modern biotechnology, new diagnostic techniques and treatment models of constitution-differentiation, disease-differentiation, and syndrome-differentiation can be established for the development of individualized Chinese medicine treatment and health medicine for the international medical community. PMID:22460443

Wang, Qi

2012-03-31

218

Expression of Drosophila Mushroom Body Mutations in Alternative Genetic Backgrounds: A Case Study of the Mushroom Body Miniature Gene (mbm)  

Microsoft Academic Search

Mutations in 12 genes regulating Drosophila melanogaster mushroom body (MB) development were each studied in two genetic backgrounds. In all cases, brain structure was qualitatively or quantitatively different after replacement of the ``original'' genetic background with that of the Canton Special wild-type strain. The mushroom body miniature gene (mbm) was investigated in detail. mbm supports the maintenance of MB Kenyon

J. Steven de Belle; Martin Heisenberg

1996-01-01

219

ALTERED SENSITIVITY OF THE MOUSE FETUS TO IMPAIRED PROSTATIC BUD FORMATION BY DIOXIN: INFLUENCE OF GENETIC BACKGROUND AND NULL EXPRESSION OF TGF-ALFA AND EGF  

EPA Science Inventory

Altered sensitivity of the mouse fetus to impaired prostatic bud formation by dioxin: Influence of genetic background and null expression of TGF and EGF. Rasmussen, N.T., Lin T-M., Fenton, S.E., Abbott, B.D. and R.E. Peterson. 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD)...

220

SURVIVAL AND DEGRADATIVE CAPACITY OF PSEUDOMONAS PUTIDA INDUCED OR CONSTITUTIVELY EXPRESSING PLASMA-MEDIATED DEGRADATION OF 2,4-DICHLOROPHENOXYACETATE (TFD) IN SOIL  

EPA Science Inventory

The survival of genetically altered Pseudomonas putida strains harboring an inducible plasmid, PRO101, or a constitutive plasmid, PRO103, was compared. hese plasmids encode for the degradation of 2,4-dichlorophenoxyacetate (TFD) to 2-chloromaleylacetate, and the maintenance of ei...

221

SURVIVAL AND DEGRADATIVE CAPACITY OF PSEUDOMONAS PUTIDA INDUCED OR CONSTITUTIVELY EXPRESSING PLASMID-MEDIATED DEGRADATION OF 2,4-DICHLOROPHENOXYACETATE (TFD) IN SOIL  

EPA Science Inventory

Survival of genetically altered Pseudonomas putida strains harboring an inducible plasmid, pRO101, or a constitutive plasmid, pRO103, was compared. hese plasmids encoded for the degradation of 2,4-dichlorophenoxyacetate (TFD) to 2-chloromaleylacetate, and the maintenance of eithe...

222

Light-grown plants of transgenic tobacco expressing an introduced oat phytochrome A gene under the control of a constitutive viral promoter exhibit persistent growth inhibition by far-red light  

Microsoft Academic Search

A comparison of the photoregulation of development has been made for etiolated and light-grown plants of wild-type (WT) tobacco (Nicotiana tabacun L.) and an isogenic transgenic line which expresses an introduced oat phytochrome gene (phyA) under the control of a constitutive viral promoter. Etiolated seedlings of both the WT and transgenic line showed irradiance-dependent inhibition of hypocotyl growth under continuous

Alex McCormac; Garry Whitelam; Harry Smith

1992-01-01

223

Contesting the Constitution: The Constitutional Dialogues.  

ERIC Educational Resources Information Center

|This historical dramatization, prepared for presentation at the 1985 Wyoming Chatauqua, contains three dialogues, set during the administration of President Thomas Jefferson and presenting the issues surrounding the drafting and ratification of the U.S. Constitution. The dialogues are designed to be presented in three segments to permit…

Hilenski, Ferdinand Alexi

224

Differential measurement of constitutive (COX1) and inducible (COX2) cyclooxygenase expression in human umbilical vein endothelial cells using specific immunometric enzyme immunoassays  

Microsoft Academic Search

We have produced and characterized monoclonal antibodies (mAbs) directed against a specific carboxyterminal sequence of human cyclooxygenase-2 (residues 580–598). A rabbit polyclonal antiserum was also raised against another sequence of 10 amino acids (residues 570–581) not present in human constitutive cyclooxygenase-1. Affinity-purified polyclonal antibodies, coated on microtiter plates, were used as capture antibodies in a two-site immunometric assay, with an

Christophe Créminon; Aďda Habib; Jacques Maclouf; Philippe Pradelles; Jacques Grassi; Yveline Frobert

1995-01-01

225

[Pediatric constitutional therapy].  

PubMed

The basic idea of constitutional medication goes back to ancient times. These experiences were integrated in the western world and in modern times supplemented by new knowledge. Our constitutional medicine has roots in the unique and brilliant idea of "Miasmatic Theories" of Hahnemann and the other famous doctors. We have worked since on 1950 theoretical and practical aspects of constitutional homoeopathic medicine for children. PMID:7681892

Dorcsi, M

1993-02-01

226

Interpreting the Constitution.  

ERIC Educational Resources Information Center

Discusses constitutional interpretations relating to capital punishment and protection of human dignity. Points out the document's effectiveness in creating a new society by adapting its principles to current problems and needs. Considers two views of the Constitution that lead to controversy over the legitimacy of judicial decisions. (PS)

Brennan, William J., Jr.

1987-01-01

227

The Constitution by Cell  

ERIC Educational Resources Information Center

|On their visit to the National Archives Experience in Washington, D.C., students in Jenni Ashley and Gay Brock's U.S. history classes at the Potomac School in McLean, Virginia, participated in a pilot program called "The Constitution by Cell." Armed with their cell phones, a basic understanding of the Constitution, and a willingness to…

Greenhut, Stephanie; Jones, Megan

2010-01-01

228

Terrorism and the Constitution  

Microsoft Academic Search

How do terrorism and the Iran-Contra hearings relate to the Constitution? My thesis is that there is a tendency for the executive of this or any nation to eschew even constitutionally mandated avenues of problem solving considered to be cumbersome, inefficient, or inimical to the executive’s vision of the national interest in foreign affairs. There is also a tendency to

Christopher L. Blakesley

1987-01-01

229

Restoring the Right Constitution?  

Microsoft Academic Search

After years of relative neglect, the past few decades have witnessed a dramatic renewal of interest in the natural law tradition within philosophical circles. This natural law renaissance, however, has yet to bear much fruit within American constitutional discourse, especially among commentators on the left. In light of its low profile within contemporary constitutional debates, an effort to formulate a

Eduardo M. Peńalver

2006-01-01

230

Constitutive activation of nuclear factor-E2-related factor 2 induces biotransformation enzyme and transporter expression in livers of mice with hepatocyte-specific deletion of Kelch-like ECH-associated protein 1.  

PubMed

Chemicals that activate nuclear factor-E2-related factor 2 (Nrf2) often increase multidrug-resistance-associated protein (Mrp) expression in liver. Hepatocyte-specific deletion of Kelch-like ECH-associated protein 1 (Keap1) activates Nrf2. Use of hepatocyte-specific Keap1 deletion represents a nonpharmacological method to determine whether constitutive Nrf2 activation upregulates liver transporter expression in vivo. The mRNA, protein expression, and localization of several biotransformation and transporters were determined in livers of wild-type and hepatocyte-specific Keap1-null mice. Sulfotransferase 2a1/2, NADP(H):quinone oxidoreductase 1, cytochrome P450 2b10, 3a11, and glutamate-cysteine ligase catalytic subunit expression were increased in livers of Keap1-null mice. Organic anion-transporting polypeptide 1a1 expression was nearly abolished, as compared to that detected in livers of wild-type mice. By contrast, Mrp 1-5 mRNA and protein levels were increased in Keap1-null mouse livers, with Mrp4 expression being more than 15-fold higher than wild types. In summary, Nrf2 has a significant role in affecting Oatp and Mrp expressions. PMID:21538727

Cheng, Qiuqiong; Taguchi, Keiko; Aleksunes, Lauren M; Manautou, José E; Cherrington, Nathan J; Yamamoto, Masayuki; Slitt, Angela L

2011-05-02

231

Development of Non-Antibiotic-Resistant, Chromosomally Based, Constitutive and Inducible Expression Systems for aroA-Attenuated Salmonella enterica Serovar Typhimurium  

Microsoft Academic Search

Live-vaccine delivery systems expressing two model antigens from Mycoplasma hyopneumoniae ,F 2P97 (Adh) and NrdF, were constructed using Salmonella enterica serovar Typhimurium aroA (STM-1), and immunoge- nicity in mice was evaluated. Recombinant plasmid-based expression (PBE) and chromosomally based expres- sion (CBE) systems were constructed. The PBE system was formed by cloning both antigen genes into pJLA507 to create an operon

Jake N. Matic; Tamsin D. Terry; David Van Bockel; Tracy Maddocks; David Tinworth; Michael P. Jennings; Steven P. Djordjevic; Mark J. Walker

2009-01-01

232

Shared Constitutional Interpretation  

Microsoft Academic Search

In United States v. Dickerson the Supreme Court reaffirmed its decision in Miranda v. Arizona, stating that it was a 'constitutional decision' and, thus, not subject to congressional overruling. At the same time, the Dickerson Court reiterated Miranda's \\

Michael C. Dorf; Barry Friedman

2000-01-01

233

Constitution of calycopterin  

Microsoft Academic Search

Summary  The constitution of calycopterin as 5 ? 4?-dihydroxy-3 ? 6 ? 7 ? 8-tetramethoxy-flavone has been confirmed. Calycopterin diethyl\\u000a ether has been shown to have ethoxyl groups in the 5 and 4?-positions, since on fission with alcoholic alkali, it yieldsp-ethoxy benzoic acid and 2-hydroxy-? ? 3 ? 4 ? 5-tetramethoxy-6-ethoxy acetophenone. The constitution of the ketone has been\\u000a established by

T. R. Seshadri; V. Venkateswarlu

1946-01-01

234

Background Information  

Center for Biologics Evaluation and Research (CBER)

Text VersionPage 1. Background Information ... These have been labeled to remove fluid from patients suffering from volume overload. ... More results from www.fda.gov/downloads/advisorycommittees/committeesmeetingmaterials

235

Bt rice harbouring cry genes controlled by a constitutive or wound-inducible promoter: protection and transgene expression under Mediterranean field conditions.  

PubMed

Seven homozygous transgenic lines of two European commercial cultivars of rice (Ariete (A) and Senia (S)), harbouring the cry1B or cry1Aa Bacillus thuringiensis (Bt) delta-endotoxin genes, were field evaluated for protection from striped stem borer (SSB) (Chilo suppressalis) damage during the 2001 and 2002 summer crop seasons in the Delta de l'Ebre region, Spain. The plant codon-optimized toxin gene was placed under the control of the promoter of either the constitutive ubi1 gene or the wound-inducible mpi gene from maize. Stable, high-level, insecticidal protein accumulation was observed throughout root, leaf and seed tissues of field-grown plants harbouring the cry1B (lines A64.1, A33.1, A3.4 and S98.9) or cry1Aa (lines S05.1 and A19.14) genes under the control of the ubi1 promoter. Conversely, no toxin was detected in unwounded vegetative tissues of the A9.1 line harbouring the cry1B gene controlled by the mpi promoter, indicating that natural environmental stresses did not trigger the activity of the wound-inducible promoter. However, the toxin accumulated at 0.2% total soluble proteins in A9.1 sheath tissue exhibiting brown lesions resulting from SSB damage. The agronomical traits and performance of the transgenic lines were generally comparable with parental controls, except in the two lines accumulating Cry1Aa, which exhibited a high frequency of plants non-true to type. Natural infestation was assisted with manual infestations of L2/L3 SSB larvae in border control plants surrounding the experimental plots, which served as a reservoir for the second-cycle SSB population. The observation of damage (brown lesions and dead hearts) during the crop season and dissection of plants at harvest stage revealed a range of protection amongst the transgenic lines, which was highly consistent with the level of toxin accumulation and with previous experience in greenhouse assays. Lines A3.4 and S05.1 were found to exhibit stable and full protection against SSB attacks, mediated by the accumulation of Cry1B and Cry1Aa toxin, respectively, which was comparable with that afforded by the spraying of chemical insecticides on control plants. The wound-induced A9.1 line exhibited a satisfactory level of protection, with a notably low level of penetration of SSB larvae in the stems, but higher external symptoms than constitutive lines, probably due to the time lag to benefit from the protective effect of Cry1B. PMID:17168888

Breitler, Jean Christophe; Vassal, Jean Michel; del Mar Catala, Maria; Meynard, Donaldo; Marfŕ, Victoria; Melé, Enric; Royer, Monique; Murillo, Isabel; San Segundo, Blanca; Guiderdoni, Emmanuel; Messeguer, Joaquima

2004-09-01

236

Molecular identification of phenylalanine ammonia-lyase as a substrate of a specific constitutively active Arabidopsis CDPK expressed in maize protoplasts  

Microsoft Academic Search

Phenylalanine ammonia-lyase (PAL) is a key enzyme in pathogen defence, stress response and secondary metabolism and is subject to post-translational phosphorylation. In order to address the significance of this phenomenon it is necessary to identify the protein kinase (PK) responsible and place it in its regulatory circuit. Using protoplast transient expression of Arabidopsis kinase genes coupled to immunocomplex kinase assay,

Shu-Hua Cheng; Jen Sheen; Chris Gerrish; G. Paul Bolwell

2001-01-01

237

Dehydrin2 is a stress-inducible, whereas Dehydrin1 is constitutively expressed but up-regulated gene under varied cues in tea [Camellia sinensis (L.) O. Kuntze].  

PubMed

Two expressed sequence tags with similarity to dehydrin were cloned to full-length (CsDHN1 and CsDHN2) through rapid amplification of cDNA ends. CsDHN1 and CsDHN2 were 1,027 and 992 base pair long and encoded for predicted polypeptides of 260 and 201 amino acids, respectively. Deduced CsDHN1 protein had a S-segment and three lysine-rich consensus motifs (K-segments). The Y-segment was, however, absent in the deduced CsDHN1. CsDHN2 had three Y motifs, one S-segment and two K-segments. Expression of CsDHN1 was visible at all the time points of study, though up-regulation was observed in response to winter dormancy (WD) as well as abiotic stresses [low temperature, sodium chloride, polyethylene glycol, and hydrogen peroxide]. Expression of CsDHN2 was strongly up-regulated within 1 h of exposure to abiotic stresses as well in the tissue harvested during WD in contrast to the respective "control" for abiotic stresses and in tissue during the period of active growth, when the expression was not detectable. PMID:23275208

Paul, Asosii; Kumar, Sanjay

2012-12-30

238

63. Long-Term Constitutive Expression of the Therapeutic Gene, IL2RG, Causes T-Cell Lymphomas in a Gene Therapy Model for XSCID  

Microsoft Academic Search

The successful gene therapy clinical trials, where the immune function of patients with X-linked severe combined immune deficiency (XSCID) was restored, demonstrated the utility for vector mediated gene transduction of hematopoietic stem cells in the treatment of a life threatening disease. However, the occurrence of T-cell leukemias in three patients, with the suspected oncogenic event resulting from upregulation of expression

Niels-Bjarne Woods; Virginie Bottero; Manfred Schmidt; Christof von Kalle; Inder M. Verma

2006-01-01

239

THE IDEA OF A CONSTITUTION AND WHY CONSTITUTIONS MATTER  

Microsoft Academic Search

very state in the world claims to have a constitution but not all of them have constitutional government. Constitutional government in the classical sense requires a certain type of constitution, one that limits the powers of political authorities and is not susceptible to easy modification or abrogation by transient holders of political power. The term 'constitution' has acquired at least

Suri Ratnapala

240

Expression of a synthetic copy of the bovine chymosin gene in Aspergillus awamori from constitutive and pH-regulated promoters and secretion using two different pre-pro sequences.  

PubMed

A copy of the bovine chymosin gene (chy) with a codon usage optimized for its expression in Aspergillus awamori was constructed starting from synthetic oligonucleotides. To study the ability of this filamentous fungus to secrete bovine prochymosin, two plasmids were constructed in which the transcriptional, translational, and secretory control regions of the A. nidulans gpdA gene and pepB genes were coupled to either preprochymosin or prochymosin genes. Secretion of a protein enzymatically and immunologically indistinguishable from bovine chymosin was achieved in A. awamori transformants with each of these constructions. In all cases, the primary translation product (40.5 kDa) was self-processed to a mature chymosin polypeptide having a molecular weight of 35.6 kDa. Immunological assays indicated that most of the chymosin was secreted to the extracellular medium. Hybridization analysis of genomic DNA from chymosin transformants showed chromosomal integration of prochymosin sequences and, in some transformants, multiple copies of the expression cassettes were observed. Expression from the gpdA promoter was constitutive, whereas expression from the pepB promoter was strongly influenced by pH. A very high expression from the pepB promoter was observed during the growth phase. The A. awamori pepB gene terminator was more favorable for chymosin production than the S. cerevisiae CYC1 terminator. PMID:12783481

Cardoza, R E; Gutiérrez, S; Ortega, N; Colina, A; Casqueiro, J; Martín, J F

2003-08-01

241

Improved biomass productivity and water use efficiency under water deficit conditions in transgenic wheat constitutively expressing the barley HVA1 gene  

Microsoft Academic Search

The ABA-responsive barley gene HVA1, a member of group 3 late embryogenesis abundant (LEA) protein genes, was introduced into spring wheat (Triticum aestivum L.) cv. Hi-Line using the biolistic bombardment method. High levels of expression of the HVA1 gene, regulated by the maize ubi1 promoter, were observed in leaves and roots of independent transgenic wheat plants and were inherited by

Elumalai Sivamani; Ahmed Bahieldinb; Jon M. Wraith; Thamir Al-Niemi; William E. Dyer; Tuan-Hua David Ho; Rongda Qu

2000-01-01

242

Three second chromosome-linked clustered Cyp6 genes show differential constitutive and barbital-induced expression in DDT-resistant and susceptible strains of Drosophila melanogaster  

Microsoft Academic Search

The level of expression of the Cyp6a2 gene is much higher in the DDT-resistant 91-R strain than in the susceptible 91-C strain of Drosophila melanogaster (Waters et al. (1992b) Proc. Natl. Acad. Sci. USA, 89, 4855–4859). To understand the role of Cyp6a2 and related genes in insecticide resistance, we have isolated and characterized two new Cyp6 genes from the 91-R

Sushmita Maitra; Susan M. Dombrowski; Larry C. Waters; Ranjan Ganguly

1996-01-01

243

Heat-shock protein 70 (Hsp70) expression in four limpets of the genus Lottia: interspecific variation in constitutive and inducible synthesis correlates with in situ exposure to heat stress.  

PubMed

Limpets of the genus Lottia occupy a broad vertical distribution on wave-exposed rocky shores, a range that encompasses gradients in the frequency and severity of thermal and desiccation stress brought on by aerial emersion. Using western blot analysis of levels of heat-shock protein 70 (Hsp70), we examined the heat-shock responses of four Lottia congeners: Lottia scabra and L. austrodigitalis, which occur in the high-intertidal zone, and L. pelta and L. scutum, which are restricted to the low- and mid-intertidal zones. Our results suggest distinct strategies of Hsp70 expression in limpets occupying different heights and orientations in the rocky intertidal zone. In freshly field-collected animals and in specimens acclimated at ambient temperature ( approximately 14 degrees C) for 14 days, the two high-intertidal species had higher constitutive levels of Hsp70 than the low- and mid-intertidal species. During aerial exposure to high temperatures, the two low-shore species and L. austrodigitalis exhibited an onset of Hsp70 expression at 28 degrees C; no induction of Hsp70 occurred in L. scabra. Our findings suggest that high-intertidal congeners of Lottia employ a "preparative defense" strategy involving maintenance of high constitutive levels of Hsp70 in their cells as a mechanism for protection against periods of extreme and unpredictable heat stress. PMID:18840778

Dong, Yunwei; Miller, Luke P; Sanders, Jon G; Somero, George N

2008-10-01

244

A rapid and transient synthesis of nitric oxide (NO) by a constitutively expressed type II NO synthase in the guinea-pig suprachiasmatic nucleus  

PubMed Central

We have measured extracellular NO/NO2? concentrations in guinea-pig suprachiasmatic nucleus (SCN) brain slices using fast cyclic voltammetry. A rapid and transient signal equivalent to 2.2±0.2??M NO/NO2? (mean±s.e.mean, n=13) was detected at 1.26?V, the peak oxidation potential for NO, following local electrical stimulation (five pulses of 0.1?ms duration at 100?Hz, delivered every 5?min).The NO/NO2? signal was inhibited by the non-selective nitric oxide synthase (NOS) inhibitors L-NAME, L-NMMA and the highly selective type II NOS (iNOS) inhibitor 1400?W (Garvey et al., 1997) in a concentration-dependent manner. IC50 values were 229??M (65?–?801, n=3, geomean and 95% confidence intervals (C.I.)), 452?nM (88?–?2310, n=5), and 14.2??M (3.6?–?54.4, n=5), with maximum inhibitions of 82.8±6.7, 46.0±8.1, and 90.6±3.6%, respectively.Exposure of the slices to the protein synthesis inhibitor cyclohexamide or the inhibitor of type II NOS induction dexamethasone immediately following slice cutting, and for a subsequent 4?–?5?h, did not inhibit the NO/NO2? signal.The evoked NO/NO2? signal was not reduced following 6?h perfusion in Ca2+-free media, consistent with a Ca2+-independent type II NOS activity.PCR for type II NOS revealed the presence of this isotype in the SCN, even immediately following removal of the brain.These studies provide the first evidence to suggest a functional, constitutively-active type II NOS within the brain of normal, healthy adult animals, and add type II NOS to the multiple isotypes of NO synthase playing a role within the mammalian SCN.

Starkey, Sarah J; Grant, Andrea L; Hagan, Russell M

2001-01-01

245

Human & Constitutional Rights  

NSDL National Science Digital Library

The Arthur W. Diamond Law Library at Columbia Law School maintains this excellent resource for finding materials on human rights and constitutional rights. The metasite serves students, scholars, and practitioners as a portal to documents and Internet resources on international and domestic law related to human and constitutional rights. The information resources are divided into six sections: Country Reports, International Links, Regional Links, National Links, Documents, and Other Web Resources. Each section is clearly organized into neat lists or pop-up menus to ease navigation. Marylin Raisch -- the International, Comparative, and Foreign Law Librarian responsible for this metasite -- also provides a Hot Topics section, which posts information on current events related to human and constitutional rights.

246

Comprehensive Genome-Wide Survey, Genomic Constitution and Expression Profiling of the NAC Transcription Factor Family in Foxtail Millet (Setaria italica L.)  

PubMed Central

The NAC proteins represent a major plant-specific transcription factor family that has established enormously diverse roles in various plant processes. Aided by the availability of complete genomes, several members of this family have been identified in Arabidopsis, rice, soybean and poplar. However, no comprehensive investigation has been presented for the recently sequenced, naturally stress tolerant crop, Setaria italica (foxtail millet) that is famed as a model crop for bioenergy research. In this study, we identified 147 putative NAC domain-encoding genes from foxtail millet by systematic sequence analysis and physically mapped them onto nine chromosomes. Genomic organization suggested that inter-chromosomal duplications may have been responsible for expansion of this gene family in foxtail millet. Phylogenetically, they were arranged into 11 distinct sub-families (I-XI), with duplicated genes fitting into one cluster and possessing conserved motif compositions. Comparative mapping with other grass species revealed some orthologous relationships and chromosomal rearrangements including duplication, inversion and deletion of genes. The evolutionary significance as duplication and divergence of NAC genes based on their amino acid substitution rates was understood. Expression profiling against various stresses and phytohormones provides novel insights into specific and/or overlapping expression patterns of SiNAC genes, which may be responsible for functional divergence among individual members in this crop. Further, we performed structure modeling and molecular simulation of a stress-responsive protein, SiNAC128, proffering an initial framework for understanding its molecular function. Taken together, this genome-wide identification and expression profiling unlocks new avenues for systematic functional analysis of novel NAC gene family candidates which may be applied for improvising stress adaption in plants.

Puranik, Swati; Sahu, Pranav Pankaj; Mandal, Sambhu Nath; B., Venkata Suresh; Parida, Swarup Kumar; Prasad, Manoj

2013-01-01

247

Matrix GLA protein is a developmental regulator of chondrocyte mineralization and, when constitutively expressed, blocks endochondral and intramembranous ossification in the limb.  

PubMed

Matrix GLA protein (MGP), a gamma-carboxyglutamic acid (GLA)-rich, vitamin K-dependent and apatite-binding protein, is a regulator of hypertrophic cartilage mineralization during development. However, MGP is produced by both hypertrophic and immature chondrocytes, suggesting that MGP's role in mineralization is cell stage-dependent, and that MGP may have other roles in immature cells. It is also unclear whether MGP regulates the quantity of mineral or mineral nature and quality as well. To address these issues, we determined the effects of manipulations of MGP synthesis and expression in (a) immature and hypertrophic chondrocyte cultures and (b) the chick limb bud in vivo. The two chondrocyte cultures displayed comparable levels of MGP gene expression. Yet, treatment with warfarin, a gamma-carboxylase inhibitor and vitamin K antagonist, triggered mineralization in hypertrophic but not immature cultures. Warfarin effects on mineralization were highly selective, were accompanied by no appreciable changes in MGP expression, alkaline phosphatase activity, or cell number, and were counteracted by vitamin K cotreatment. Scanning electron microscopy, x-ray microanalysis, and Fourier-transform infrared spectroscopy revealed that mineral forming in control and warfarin-treated hypertrophic cell cultures was similar and represented stoichiometric apatite. Virally driven MGP overexpression in cultured chondrocytes greatly decreased mineralization. Surprisingly, MGP overexpression in the developing limb not only inhibited cartilage mineralization, but also delayed chondrocyte maturation and blocked endochondral ossification and formation of a diaphyseal intramembranous bone collar. The results show that MGP is a powerful but developmentally regulated inhibitor of cartilage mineralization, controls mineral quantity but not type, and appears to have a previously unsuspected role in regulating chondrocyte maturation and ossification processes. PMID:10579728

Yagami, K; Suh, J Y; Enomoto-Iwamoto, M; Koyama, E; Abrams, W R; Shapiro, I M; Pacifici, M; Iwamoto, M

1999-11-29

248

Constitutive expression of two endochitinases from root nodules of Elaeagnus umbellata confers resistance on transgenic Arabidopsis plants against the fungal pathogen Botrytis cinerea  

Microsoft Academic Search

Plant chitinases have been known as pathogenesis-related (PR) proteins, but recent studies suggest that they play functional\\u000a roles during normal plant growth and development. We previously isolated two cDNA clones encoding endochitinases,EuNOD-CHT1 and -CHT2, from the root nodules ofElaeagnus umbellata. These genes show differential expression patterns, with theEuNOD-CHT1 gene being active in the root nodules and meristems, whileEuNOD-CHT2 is preferentially

Yaw Joo Kim; Ho Bang Kim; Eun Hye Baek; Sunggi Heu; Chung Sun An

2005-01-01

249

Dynamic alternations in cellular and molecular components during blossom-end rot development in tomatoes expressing sCAX1, a constitutively active Ca2+/H+ antiporter from Arabidopsis.  

PubMed

Although calcium (Ca) concentration in cellular compartments has been suggested to be tightly regulated, Ca deficiency disorders such as blossom-end rot (BER) in tomato (Solanum lycopersicum) fruit may be induced by abnormal regulation of Ca partitioning and distribution in the cell. The objectives of this work were to analyze the effects of high expression of the constitutively functional Arabidopsis (Arabidopsis thaliana) Ca(2+)/H(+) exchanger (sCAX1) tonoplast protein in tomato fruit on cellular Ca partitioning and distribution, membrane integrity, and the transcriptional profile of genes potentially involved in BER development. Wild-type and sCAX1-expressing tomato plants were grown in a greenhouse. Wild-type plants did not develop BER, whereas sCAX1-expressing plants reached 100% BER incidence at 15 d after pollination. The sCAX1-expressing fruit pericarp had higher total tissue and water-soluble Ca concentrations, lower apoplastic and cytosolic Ca concentrations, higher membrane leakage, and Ca accumulation in the vacuole of sCAX1-expressing cells. Microarray analysis of healthy sCAX1-expressing fruit tissue indicated down-regulation of genes potentially involved in BER development, such as genes involved in membrane structure and repair and cytoskeleton metabolism, as well as up-regulation of genes that may have limited BER damage expansion, such as genes coding for heat shock proteins, glutathione S-transferases, and peroxidases. The results indicate that the high expression of the sCAX1 gene reduces cytosolic and apoplastic Ca concentrations, affecting plasma membrane structure and leading to BER symptom development in the fruit tissue. PMID:21464475

Tonetto de Freitas, Sergio; Padda, Malkeet; Wu, Qingyu; Park, Sunghun; Mitcham, Elizabeth J

2011-04-04

250

Dynamic Alternations in Cellular and Molecular Components during Blossom-End Rot Development in Tomatoes Expressing sCAX1, a Constitutively Active Ca2+/H+ Antiporter from Arabidopsis1[W][OA  

PubMed Central

Although calcium (Ca) concentration in cellular compartments has been suggested to be tightly regulated, Ca deficiency disorders such as blossom-end rot (BER) in tomato (Solanum lycopersicum) fruit may be induced by abnormal regulation of Ca partitioning and distribution in the cell. The objectives of this work were to analyze the effects of high expression of the constitutively functional Arabidopsis (Arabidopsis thaliana) Ca2+/H+ exchanger (sCAX1) tonoplast protein in tomato fruit on cellular Ca partitioning and distribution, membrane integrity, and the transcriptional profile of genes potentially involved in BER development. Wild-type and sCAX1-expressing tomato plants were grown in a greenhouse. Wild-type plants did not develop BER, whereas sCAX1-expressing plants reached 100% BER incidence at 15 d after pollination. The sCAX1-expressing fruit pericarp had higher total tissue and water-soluble Ca concentrations, lower apoplastic and cytosolic Ca concentrations, higher membrane leakage, and Ca accumulation in the vacuole of sCAX1-expressing cells. Microarray analysis of healthy sCAX1-expressing fruit tissue indicated down-regulation of genes potentially involved in BER development, such as genes involved in membrane structure and repair and cytoskeleton metabolism, as well as up-regulation of genes that may have limited BER damage expansion, such as genes coding for heat shock proteins, glutathione S-transferases, and peroxidases. The results indicate that the high expression of the sCAX1 gene reduces cytosolic and apoplastic Ca concentrations, affecting plasma membrane structure and leading to BER symptom development in the fruit tissue.

Tonetto de Freitas, Sergio; Padda, Malkeet; Wu, Qingyu; Park, Sunghun; Mitcham, Elizabeth J.

2011-01-01

251

Enhanced resistance to blast fungus and bacterial blight in transgenic rice constitutively expressing OsSBP, a rice homologue of mammalian selenium-binding proteins.  

PubMed

The rice Oryza sativa selenium-binding protein homologue (OsSBP) gene encodes a homologue of mammalian selenium-binding proteins, and it has been isolated as one of the genes induced by treating a plant with a cerebroside elicitor from rice blast fungus. The possible role of OsSBP in plant defense was evaluated by using a transgenic approach. Plants overexpressing OsSBP showed enhanced resistance to a virulent strain of rice blast fungus as well as to rice bacterial blight. The expression of defense-related genes and the accumulation of phytoalexin after infection by rice blast fungus were accelerated in the OsSBP overexpressors. A higher level of H(2)O(2) accumulation and reduced activity of such scavenging enzymes as ascorbate peroxidase and catalase were seen when the OsSBP-overexpressing plants were treated with the protein phosphatase 1 inhibitor, calyculin A. These results suggest that the upregulation of OsSBP expression conferred enhanced tolerance to different pathogens, possibly by increasing plant sensitivity to endogenous defense responses. Additionally, the OsSBP protein might have a role in modulating the defense mechanism to biotic stress in rice. PMID:15118317

Sawada, Kazutoshi; Hasegawa, Morifumi; Tokuda, Lena; Kameyama, Junko; Kodama, Osamu; Kohchi, Takayuki; Yoshida, Kazuya; Shinmyo, Atsuhiko

2004-04-01

252

The Evolving Constitution.  

ERIC Educational Resources Information Center

|Argues that bicentennial celebrations of the U.S. Constitution should be focused on struggles throughout the life of the document rather than the "miracle" of its birth. Illustrates this point by reference to changes in the voting rights and citizenship of black citizens. (BSR)|

Marshall, Thurgood

1987-01-01

253

Crushed Salt Constitutive Model  

SciTech Connect

The constitutive model used to describe the deformation of crushed salt is presented in this report. Two mechanisms -- dislocation creep and grain boundary diffusional pressure solution -- are combined to form the basis for the constitutive model governing the deformation of crushed salt. The constitutive model is generalized to represent three-dimensional states of stress. Upon complete consolidation, the crushed-salt model reproduces the Multimechanism Deformation (M-D) model typically used for the Waste Isolation Pilot Plant (WIPP) host geological formation salt. New shear consolidation tests are combined with an existing database that includes hydrostatic consolidation and shear consolidation tests conducted on WIPP and southeastern New Mexico salt. Nonlinear least-squares model fitting to the database produced two sets of material parameter values for the model -- one for the shear consolidation tests and one for a combination of the shear and hydrostatic consolidation tests. Using the parameter values determined from the fitted database, the constitutive model is validated against constant strain-rate tests. Shaft seal problems are analyzed to demonstrate model-predicted consolidation of the shaft seal crushed-salt component. Based on the fitting statistics, the ability of the model to predict the test data, and the ability of the model to predict load paths and test data outside of the fitted database, the model appears to capture the creep consolidation behavior of crushed salt reasonably well.

Callahan, G.D.

1999-02-01

254

Disputing the Constitution.  

ERIC Educational Resources Information Center

Constitutional law is a good way to introduce students to fundamental debates over means and ends, over what means work and at what costs, and over what ends are not merely desirable, but may be legitimately achieved even through the application of collective force. It also offers an exciting way to teach logic. (MLW)

Pyle, Christopher H.

1987-01-01

255

Amending Higher Education's Constitution  

ERIC Educational Resources Information Center

|Beginning in 1934, representatives of the American Association of University Professors (AAUP) and the Association of American Colleges (AAC) met and drafted the definitive statement on academic freedom and tenure. Like the U.S. Constitution, the 1940 "Statement on Principles of Academic Freedom and Tenure" was a commendable, if deficient,…

Trower, Cathy A.

2008-01-01

256

South Africa's Constitutional Change.  

ERIC Educational Resources Information Center

|Describes the striking dichotomy of South Africa's beauty and the squalor resulting from the apartheid policies of the government. Reviews reactions of black South Africans to recent constitutional changes and details efforts to secure more sweeping reform. Includes stories of several individuals who have taken actions which oppose the system of…

Getman, Thomas

1987-01-01

257

The Cap'n'Collar basic leucine zipper transcription factor Nrf2 (NF-E2 p45-related factor 2) controls both constitutive and inducible expression of intestinal detoxification and glutathione biosynthetic enzymes.  

PubMed

Northern blotting has shown that mouse small intestine contains relatively large amounts of the nuclear factor-E2 p45-related factor (Nrf) 2 transcription factor but relatively little Nrf1. Regulation of intestinal antioxidant and detoxication enzymes by Nrf2 has been assessed using a mouse line bearing a targeted disruption of the gene encoding this factor. Both Nrf2-/- and Nrf2+/+ mice were fed a control diet or one supplemented with either synthetic cancer chemopreventive agents [butylated hydroxyanisole (BHA), ethoxyquin (EQ), or oltipraz] or phytochemicals [indole-3-carbinol, cafestol and kahweol palmitate, sulforaphane, coumarin (CMRN), or alpha-angelicalactone]. The constitutive level of NAD(P)H:quinone oxidoreductase (NQO) and glutathione S-transferase (GST) enzyme activities in cytosols from small intestine was typically found to be between 30% and 70% lower in samples prepared from Nrf2 mutant mice fed a control diet than in equivalent samples from Nrf2+/+ mice. Most of the chemopreventive agents included in this study induced NQO and GST enzyme activities in the small intestine of Nrf2+/+ mice. Increases of between 2.7- and 6.2-fold were observed in wild-type animals fed diets supplemented with BHA or EQ; increases of about 2-fold were observed with a mixture of cafestol and kahweol palmitate, CMRN, or alpha-angelicalactone; and increases of 1.5-fold were measured with sulforaphane. Immunoblotting confirmed that in the small intestine, the constitutive level of NQO1 is lower in the Nrf2-/- mouse, and it also showed that induction of the oxidoreductase was substantially diminished in the mutant mouse. Immunoblotting class-alpha and class-mu GST showed that constitutive expression of most transferase subunits is also reduced in the small intestine of Nrf2 mutant mice. Significantly, induction of class-alpha and class-mu GST by EQ, BHA, or CMRN is apparent in the gene knockout animal. No consistent change in the constitutive levels of the catalytic heavy subunit of gamma-glutamylcysteinyl synthetase (GCS(h)) was observed in the small intestine of Nrf2-/- mice. However, although the expression of GCS(h) was found to be increased dramatically in the small intestine of Nrf2+/+ mice by dietary BHA or EQ, this induction was essentially abolished in the knockout mice. It is apparent that Nrf2 influences both constitutive and inducible expression of intestinal antioxidant and detoxication proteins in a gene-specific fashion. Immunohistochemistry revealed that induction of NQO1, class-alpha GST, and GCS(h) occurs primarily in epithelial cells of the small intestine. This suggests that the variation in inducibility of NQO1, Gsta1/2, and GCS(h) in the mutant mouse is not attributable to the expression of the enzymes in distinct cell types but rather to differences in the dependency of these genes on Nrf2 for induction. PMID:11309284

McMahon, M; Itoh, K; Yamamoto, M; Chanas, S A; Henderson, C J; McLellan, L I; Wolf, C R; Cavin, C; Hayes, J D

2001-04-15

258

Stimulation of human thyroid growth via the inhibitory guanine nucleotide binding (G) protein Gi: constitutive expression of the G-protein alpha subunit Gi alpha-1 in autonomous adenoma.  

PubMed Central

The alpha subunits of the stimulatory and inhibitory G proteins, Gs alpha and Gi alpha, activate transmembrane-signaling systems involved in the control of cell proliferation. We have investigated the pattern of expression of Gi alpha subtypes and Gi alpha-mediated proliferative responses in the human thyroid. Human thyroid membranes contain two subtypes of Gi alpha, Gi alpha-1 and Gi alpha-2, as assessed by using specific antibodies. The expression of Gi alpha-1 is under tight control by thyrotropin in vivo and in primary cultures of thyroid epithelial cells. In contrast, Gi alpha-1 is expressed in the absence of thyrotropin in thyroid autonomous adenoma, an endocrine-active tumor, and its levels are not regulated by thyrotropin in thyroid epithelial cells prepared from these tumors. If thyroid epithelial cells are treated with pertussis toxin to block signal transduction via Gi, the mitogenic response to serum factors is reduced. These observations demonstrate that Gi subtypes transmit growth stimuli in the human thyroid. The constitutive expression of Gi alpha-1 in autonomous adenoma may allow for the unregulated stimulation of thyroid cell proliferation by a yet unidentified signaling pathway and, thus, be causally related to autonomous growth of thyroid cells. Images

Selzer, E; Wilfing, A; Schiferer, A; Hermann, M; Grubeck-Loebenstein, B; Freissmuth, M

1993-01-01

259

The effect of high concentrations of glufosinate ammonium on the yield components of transgenic spring wheat (Triticum aestivum L.) constitutively expressing the bar gene.  

PubMed

We present an experiment done on a bar(+) wheat line treated with 14 different concentrations of glufosinate ammonium-an effective component of nonselective herbicides-during seed germination in a closed experimental system. Yield components as number of spikes per plant, number of grains per spike, thousand kernel weight, and yield per plant were thoroughly analysed and statistically evaluated after harvesting. We found that a concentration of glufosinate ammonium 5000 times the lethal dose was not enough to inhibit the germination of transgenic plants expressing the bar gene. Extremely high concentrations of glufosinate ammonium caused a bushy phenotype, significantly lower numbers of grains per spike, and thousand kernel weights. Concerning the productivity, we observed that concentrations of glufosinate ammonium 64 times the lethal dose did not lead to yield depression. Our results draw attention to the possibilities implied in the transgenic approaches. PMID:22649303

Áy, Zoltán; Mihály, Róbert; Cserháti, Mátyás; Kótai, Éva; Pauk, János

2012-05-02

260

Suppression of Constitutive SOS Expression by recA4162 (I298V) and recA4164 (L126V) requires UvrD and RecX in Escherichia coli K-12  

PubMed Central

Sensing DNA damage and initiation of genetic responses to repair DNA damage are critical to cell survival. In E. coli, RecA polymerizes on ssDNA produced by DNA damage creating a RecA-DNA filament that interacts with the LexA repressor inducing the SOS Response. RecA filament stability is negatively modulated by RecX and UvrD. recA730 (E38K) and recA4142 (F217Y) constitutively express the SOS Response. recA4162 (I298V) and recA4164 (L126V) are intragenic suppressors of the constitutive SOS phenotype of recA730. Herein, it is shown that these suppressors are not allele specific and can suppress SOSC expression of recA730 and recA4142 in cis and in trans. recA4162 and recA4164 single mutants (and the recA730 and recA4142 derivatives) are Rec+, UVR and are able to induce the SOS response after UV treatment like wild type. UvrD and RecX are required for the suppression in two (recA730,4164 and recA4142,4162) of the four double mutants tested. To explain the data, one model suggests that recAC alleles promote SOSC expression by mimicking RecA filament structures that induce SOS and the suppressor alleles mimic RecA filament at end of SOS. UvrD and RecX are attracted to these latter structures to help dismantle or destabilize the RecA filament.

Long, Jarukit Edward; Renzette, Nicholas; Sandler, Steven J.

2009-01-01

261

Quantitative Comparison of Constitutive Promoters in Human ES cells  

PubMed Central

Background Constitutive promoters that ensure sustained and high level gene expression are basic research tools that have a wide range of applications, including studies of human embryology and drug discovery in human embryonic stem cells (hESCs). Numerous cellular/viral promoters that ensure sustained gene expression in various cell types have been identified but systematic comparison of their activities in hESCs is still lacking. Methodology/Principal Findings We have quantitatively compared promoter activities of five commonly used constitutive promoters, including the human ?-actin promoter (ACTB), cytomegalovirus (CMV), elongation factor-1?, (EF1?), phosphoglycerate kinase (PGK) and ubiquitinC (UbC) in hESCs. Lentiviral gene transfer was used to ensure stable integration of promoter-eGFP constructs into the hESCs genome. Promoter activities were quantitatively compared in long term culture of undifferentiated hESCs and in their differentiated progenies. Conclusion/Significance The ACTB, EF1? and PGK promoters showed stable activities during long term culture of undifferentiated hESCs. The ACTB promoter was superior by maintaining expression in 75–80% of the cells after 50 days in culture. During embryoid body (EB) differentiation, promoter activities of all five promoters decreased. Although the EF1? promoter was downregulated in approximately 50% of the cells, it was the most stable promoter during differentiation. Gene expression analysis of differentiated eGFP+ and eGFP- cells indicate that promoter activities might be restricted to specific cell lineages, suggesting the need to carefully select optimal promoters for constitutive gene expression in differentiated hESCs.

Norrman, Karin; Fischer, Yvonne; Bonnamy, Blandine; Wolfhagen Sand, Fredrik; Ravassard, Philippe; Semb, Henrik

2010-01-01

262

Production of a Marfan cellular phenotype by expressing a mutant human fibrillin allele on a normal human or murine genetic background  

SciTech Connect

The Marfan Syndrome (MFS) is a heritable disorder of connective tissue caused by defects in fibrillin (FBN1), a 350 kD glycoprotein and principal component of the extracellular microfibril. Previous correlations of mutant transcript level and disease severity suggested a dominant negative model of MFS pathogenesis. To address this hypothesis we assembled an expression construct containing the mutant allele from a patient with severe MFS. This mutation causes skipping of FBN1 exon 2 and a frame shift, leading to a premature termination codon in exon 4. The predicted peptide would thus consist of 55 wild type and 45 missense amino acids. The construct was stably transfected into cultured human and mouse fibroblasts, and several clonal cell populations were established. Human and mouse cells expressing the truncated peptide exhibited markedly diminished fibrillin deposition and disorganized microfibrillar architecture by immunofluorescence. Pulse-chase analysis of these cells demonstrated normal levels of fibrillin synthesis but substantially decreased fibrillin deposition into the extracellular matrix. These data illustrate that expression of a mutant FBN1 allele, on a background of two normal alleles, is sufficient to disrupt normal fibrillin aggregation and reproduce the MFS cellular phenotype. This provides confirmation of a dominant negative model of MFS pathogenesis and may offer mutant allele knockout as a strategy for gene therapy. In addition, these data underscore the importance of the FBN1 amino-terminus in normal multimer formation and suggest that expression of the human extreme 5{prime} FBN1 coding sequence may be sufficient, in isolation, to produce an animal model of MFS. Indeed, transgenic mice harboring this mutant allele have been produced, and phenotype analysis is currently in progress.

Eldadah, Z.A.; Dietz, H.C. [Johns Hopkins Univ. School of Medicine, Baltimore, MD (United States); Brenn, T. [Stanford Univ. Medical Center, CA (United States)] [and others

1994-09-01

263

Genome-wide gene expression profiling of introgressed indica rice alleles associated with seedling cold tolerance improvement in a japonica rice background  

PubMed Central

Background Rice in tropical and sub-tropical areas is often subjected to cold stress at the seedling stage, resulting in poor growth and yield loss. Although japonica rice is generally more cold tolerant (CT) than indica rice, there are several favorable alleles for CT exist in indica that can be used to enhance CT in rice with a japonica background. Genome-wide gene expression profiling is an efficient way to decipher the molecular genetic mechanisms of CT enhancement and to provide valuable information for CT improvement in rice molecular breeding. In this study, the transcriptome of the CT introgression line (IL) K354 and its recurrent parent C418 under cold stress were comparatively analyzed to explore the possible CT enhancement mechanisms of K354. Results A total of 3184 differentially expressed genes (DEGs), including 195 transcription factors, were identified in both lines under cold stress. About half of these DEGs were commonly regulated and involved in major cold responsive pathways associated with OsDREB1 and OsMyb4 regulons. K354-specific cold-induced genes were functionally related to stimulus response, cellular cell wall organization, and microtubule-based movement processes that may contribute to increase CT. A set of genes encoding membrane fluidity and defensive proteins were highly enriched only in K354, suggesting that they contribute to the inherent CT of K354. Candidate gene prediction based on introgressed regions in K354 revealed genotype-dependent CT enhancement mechanisms, associated with Sir2, OsFAD7, OsWAK112d, and programmed cell death (PCD) related genes, present in CT IL K354 but absent in its recurrent parent C418. In K354, a number of DEGs were co-localized onto introgressed segments associated with CT QTLs, providing a basis for gene cloning and elucidation of molecular mechanisms responsible for CT in rice. Conclusions Genome-wide gene expression analysis revealed that genotype-specific cold induced genes and genes with higher basal expression in the CT genotype contribute jointly to CT improvement. The molecular genetic pathways of cold stress tolerance uncovered in this study, as well as the DEGs co-localized with CT-related QTLs, will serve as useful resources for further functional dissection of the molecular mechanisms of cold stress response in rice.

2012-01-01

264

Cytochrome P450 1C1 complementary DNA cloning, sequence analysis and constitutive expression induced by benzo-a-pyrene in Nile tilapia (Oreochromis niloticus).  

PubMed

CYP1C is the newest member of the CYP1 family of P450s; however, its physiological significance, inducers, and metabolic functions are unknown. In this study, a new complementary DNA of the CYP1C subfamily encoding CYP1C1 was isolated from Nile tilapia (Oreochromis niloticus) liver after intracoelomic injection with benzo-a-pyrene (BaP). The full-length cDNA was 2223 base pair (bp) long and contained an open reading frame of 1581 bp encoding a protein of 526 amino acids and a stop codon. The sequence exhibited 3' non-coding region of 642 bp. The deduced amino acid sequence of O. niloticus CYP1C1 shows similarities of 86, 82.5, 79.7, 78.7, 77.8, 75.5, 69.6 and 61.3% with scup CYP1C1, killifish CYP1C1,1C2, Japanese eel CYP1C1, zebra fish CYP1C1, common carp CYP1C1, scup CYP1C2, common carp CYP1C2 and zebra fish CYP1C2, respectively. Phylogenetic tree based on the amino acids sequences clearly shows tilapia CYP1C1 and scup CYP1C1 to be more closely related to each other than to CYP1C genes from other species. Furthermore, for measuring BaP induction of CYP1C1 mRNA in different organs of tilapia (O. niloticus), ?-actin gene as internal control was selected based on previous studies to assess their expression variability. Real time RCR results revealed that there was a large increase in CYP1C1 mRNA in liver (43.1), intestine (5.1) and muscle (2.4). PMID:22204985

Hassanin, Abeer A I; Kaminishi, Yoshino; Funahashi, Aki; Itakura, Takao

2011-12-01

265

[Constitutional requirements of rationing].  

PubMed

Rationing is an emotive issue in the field of public health. This complicates the rational discourse, which is indispensable for analyzing the rationing conditions as set out by constitutional law and which requires manifold differentiation and consideration that shall briefly be outlined in the following short contribution. Of central significance is the distinction between indirect and direct rationing as well as the reference to the essential responsibility of legislators for rationing decisions. PMID:19004184

Kluth, Winfried

2008-01-01

266

Constitutionalism: A Skeptical View  

Microsoft Academic Search

On March 17, 2010, Professor Waldron, University Professor and Professor of Law at New York University, Chichele Chair of Social and Political Theory at All Souls College, Oxford delivered the Georgetown Law Center’s thirtith annual Philip A. Hart Lecture: “ Constitutionalism: A Skeptical View.”\\u000aProfessor Waldron teaches legal and political philosophy at New York University School of Law. He was

Jeremy Waldron

2010-01-01

267

Characterization of stable, constitutively expressed, chromosomal green and red fluorescent transcriptional fusions in the select agent bacterium, Francisella tularensis Schu S4 and the surrogate type B live vaccine strain (LVS).  

PubMed

Here, we constructed stable, constitutively expressed, chromosomal green (GFP) and red fluorescent (RFP) reporters in the genome of the surrogate strain, Francisella tularensis spp. holarctica LVS (herein LVS), and the select agent, F. tularensis Schu S4. A bioinformatic approach was used to identify constitutively expressed genes. Two promoter regions upstream of the FTT1794 and rpsF(FTT1062) genes were selected and fused with GFP and RFP reporter genes in pMP815, respectively. While the LVS strains with chromosomally integrated reporter fusions exhibited fluorescence, we were unable to deliver the same fusions into Schu S4. Neither a temperature-sensitive Francisella replicon nor a pBBR replicon in the modified pMP815 derivatives facilitated integration. However, a mini-Tn7 integration system was successful at integrating the reporter fusions into the Schu S4 genome. Finally, fluorescent F. tularensis LVS and a mutant lacking MglA were assessed for growth in monocyte-derived macrophages (MDMs). As expected, when compared to wild-type bacteria, replication of an mglA mutant was significantly diminished, and the overall level of fluorescence dramatically decreased with infection time. The utility of the fluorescent Schu S4 strain was also examined within infected MDMs treated with clarithromycin and enrofloxacin. Taken together, this study describes the development of an important reagent for F. tularensis research, especially since the likelihood of engineered antibiotic resistant strains will emerge with time. Such strains will be extremely useful in high-throughput screens for novel compounds that could interfere with critical virulence processes in this important bioweapons agent and during infection of alveolar macrophages. PMID:23852642

Su, Shengchang; Saldanha, Roland; Pemberton, Adin; Bangar, Hansraj; Kawamoto, Steven A; Aronow, Bruce; Hassett, Daniel J; Lamkin, Thomas J

2013-07-13

268

Generation of functional antigen-specific T cells in defined genetic backgrounds by retrovirus-mediated expression of TCR cDNAs in hematopoietic precursor cells  

PubMed Central

We have developed an alternative to transgenesis for producing antigen-specific T cells in vivo. In this system, clonal naive T cells with defined antigen specificity are generated by retrovirus-mediated expression of T cell antigen receptor cDNAs in RAG1-deficient murine hematopoietic precursor cells. These T cells can be stimulated to proliferate and produce cytokines by exposure to antigen in vitro, and they become activated and expand in vivo after immunization. IL-2-deficient T cells generated by this technique show decreased proliferation and cytokine production, both of which can be rescued by exogenous addition of this growth factor. Thus, retrovirus-mediated expression of T cell antigen receptor cDNAs in hematopoietic precursor cells permits the rapid and efficient analysis of the life history of antigen-specific T cells in different genetic backgrounds and may allow for the long-term production of antigen-specific T cells with different functional properties for prophylactic and therapeutic purposes.

Yang, Lili; Qin, Xiao-Feng; Baltimore, David; Van Parijs, Luk

2002-01-01

269

Transforming growth factor-?1b: a second TGF-?1 paralogue in the rainbow trout (Oncorhynchus mykiss) that has a lower constitutive expression but is more responsive to immune stimulation.  

PubMed

The rainbow trout (Oncorhynchus mykiss) TGF-?1 sequence was one of the first fish cytokines described. Studies of its expression suggest it is constitutively expressed but displays refractory inducibility. Here we describe a second TGF-?1 (TGF-?1b) gene that is novel in several respects. TGF-?1b possesses typical TGF-? features, including a CXC motif and an integrin binding site, a tetrabasic cut site and a mature peptide of 112 amino acids (aa) containing nine conserved cysteine residues. The mature peptide is 83% identical to the first TGF-?1 sequence described in rainbow trout, that we designate TGF-?1a, and relative to TGF-?1a shows higher homology to Atlantic salmon TGF-?1b, zebrafish TGF-?1a, and sea bass and seabream TGF-?1. The gene organisation of salmonid TGF-?1b genes, as inferred from Atlantic salmon whole genome shotgun contigs, is a 6 exon/5 intron structure with exons 3 and 4 of salmonid TGF-?1a genes apparently fused together. The two trout TGF-?1 genes have a wide distribution in vivo, with highest expression found in immune tissues for both isoforms indicating that TGF-?1 has a predominant role in immunity of fish. Expression of both genes was also seen during the ontogeny of trout, with TGF-?1a relatively constant in expression level but TGF-?1b increasing over time. Immune responses in head kidney (HK) macrophages induced by pathogen associated molecular patterns (PAMPs), pro-inflammatory cytokines, mitogens and pathway activators highly elevated the expression level of TGF-?1b but not that of TGF-?1a. TGF-?1b expression was also increased by polyinosinic:polycytidylic acid (poly(I:C)) and/or lipopolysaccharide (LPS) stimulation in three different trout cell lines studied. Finally we show that TGF-?1b is potentially involved in defense against infection with viral haemorrhagic septicemia virus (VHSV), which had no effect on TGF-?1a expression. Thus, it is likely the TGF-?1b gene represents a copy which fulfils the major immune orchestrating functions of TGF-?1 as seen in other vertebrates. PMID:23178261

Maehr, Tanja; Costa, Maria M; Vecino, Jose L González; Wadsworth, Simon; Martin, Samuel A M; Wang, Tiehui; Secombes, Christopher J

2012-11-23

270

A New Constitutionalism for Liberals?  

Microsoft Academic Search

It has been apparent for at least a decade that liberal constitutional theory is in deep trouble. Of course there are many versions of liberal constitutional theory, but they have essentially no connection to existing practices of constitutional law, considering as practices of constitutional law all the activities of our institutions of government that implicate - interpret, advance, deal with,

Mark V. Tushnet

2003-01-01

271

The Jurisprudence of Constitutional Conflict: Constitutional Supremacy in Europe before and after the Constitutional Treaty  

Microsoft Academic Search

Abstract:?One of the core constitutional questions for national constitutional courts in the EU in the past decades has been whether to accept the claim made by the Court of Justice that EU law is the supreme law of the land, taking primacy even over conflicting national constitutional provisions. With the inclusion in the recently adopted Constitutional Treaty of a clause

Mattias Kumm

2005-01-01

272

Ethics and constitutional government.  

PubMed

The term ethics refers to a set of principles that govern acceptable, proper conduct. Attacks on the Constitution of the United States pose the most serious breach of ethics today. Our country was founded as a republic, not as a democracy. Our Founding Fathers' main concern was to protect citizens from the power of the federal government, so constitutionally, the central government has little or no authority over individual citizens except on federal property. One of the major problems today is the fact that we now have professional politicians. This is due in large part to the lure of financial gain from countless special interest groups. This would change under constitutional law because the federal budget would decrease drastically. Article 1 states that all legislative power is vested in Congress. Congress has only 18 enumerated powers, and almost half of these pertain to defense of the country. Many of our current problems are due to regulatory agencies that have become independent fiefdoms with unconstitutional legislative, as well as executive and judicial, powers. The regulatory agency most relevant to medicine, both clinical care and research, is the FDA. It is now obvious that its basic structure needs to be changed or abolished because its actions are identical to those inherent in authoritarian systems. Constructive change could come from Congress, but it would be most desirable if the Supreme Court would take the lead and reestablish the authority of the Constitution as the Supreme Law of the Land. The FDA's function could be limited to the determination of safety, but preferably its mission would be altered to that of product certification. Defenders of the current system claim that such a drastic change would be too dangerous and their prime example is thalidomide. But it is now known that the market has already solved that problem prior to the government-imposed sanctions. Realistically, market forces and their ramifications, including our legal system, provide the most effective methods of protecting the public from harmful drugs and devices. Fortunately, a model for miracles is available. It is New Zealand, which had become increasingly socialistic after WW II. As a result, they had become noncompetitive, and with the formation of the European Union, they lost their major market exports. In order to survive they made some astounding changes in the mid-1980s. They studied every agency that depended on government funding and transferred much of this work over to the private sector. They turned the remaining agencies into profit-making enterprises. These agencies had cost the government about $1 billion/year. Now, they produce about $1 billion in revenue and taxes. Without question, a return to constitutional government would be an invigorating stimulus to bioengineering research in the future. It would flourish. The eminence of this country did not develop from a strong central government. It is due to its absence, but we are rapidly reaching a point of no return. PMID:18298395

Albright, James A

2007-01-01

273

Six novel constitutive promoters for metabolic engineering of Aspergillus niger.  

PubMed

Genetic tools for the fine-tuning of gene expression levels are a prerequisite for rational strain optimization through metabolic engineering. While Aspergillus niger is an industrially important fungus, widely used for production of organic acids and heterologous proteins, the available genetic tool box for this organism is still rather limited. Here, we characterize six novel constitutive promoters of A. niger providing different expression levels. The selection of the promoters was based on published transcription data of A. niger. The promoter strength was determined with the ?-glucuronidase (gusA) reporter gene of Escherichia coli. The six promoters covered a GUS activity range of two to three orders of magnitude depending on the strain background. In order to demonstrate the power of the newly characterized promoters for metabolic engineering, they were used for heterologous expression of the cis-aconitate decarboxylase (cad1) gene of Aspergillus terreus, allowing the production of the building block chemical itaconic acid with A. niger. The CAD activity, dependent on the choice of promoter, showed a positive correlation with the specific productivity of itaconic acid. Product titers from the detection limit to up to 570 mg/L proved that the set of constitutive promoters is a powerful tool for the fine-tuning of metabolic pathways for the improvement of industrial production processes. PMID:22707054

Blumhoff, Marzena; Steiger, Matthias G; Marx, Hans; Mattanovich, Diethard; Sauer, Michael

2012-06-16

274

A constitutively expressed serum amyloid A protein gene (SAA4) is closely linked to, and shares structural similarities with, an acute-phase serum amyloid A protein gene (SAA2)  

SciTech Connect

The acute-phase reactant serum amyloid A (SAA) is a polymorphic apolipoprotein encoded by a family of highly homologous and closely linked genes: SAA1, SAA2, and SAA3. The authors have isolated a human genomic cosmid clone containing the gene encoding a fourth, constitutively expressed member of the human SAA superfamily, C-SAA, together with an SAA2*2 (SAA2{beta}) gene. The gene encoding C-SAA shares the same 5{prime} to 3{prime} orientation as SAA2*2 and has the characteristic four-exon structure of the other members of the SAA superfamily. The exons of the gene encoding C-SAA share only limited sequence identity with those of SAA1, SAA2, and SAA3; they specify an mRNA, represented by the CS-1 cDNA reported previously, which is expressed at low levels (relative to the acute-phase SAAs) in normal and acute-phase liver. The gene encoding C-SAA is located 9 kb downstream of SAA2*2 and therefore occupies the locus that has been identified as containing the SAA4 gene. 35 refs., 3 figs., 1 tab.

Steel, D.M.; Sellar, G.C.; Uhlar, C.M.; Whitehead, A.S. [Univ. of Dublin (Ireland); Simon, S. [Center for Blood Research, Boston, MA (United States); DeBeer, F.C. [Univ. of Kentucky Medical Center, Lexington, KY (United States)

1993-05-01

275

Constitution, 5 October 1988.  

PubMed

This document contains major provisions of the constitution adopted by Brazil on 5 October 1988. This constitution seeks to promote the welfare of all citizens without discrimination. The equality of all citizens is guaranteed, and the equal rights of women are specifically mentioned. Property rights are also guaranteed and defined. Female inmates are granted the right to remain with their children while breast feeding. Workers are guaranteed a minimum wage, a family allowance for dependents, maternity/paternity leave, specific incentives to protect the labor market for women, retirement benefits, free day care for preschool-age children, pay equity, and equal rights between tenured and sporadically employed workers. Agrarian reform provisions are given, including the authority to expropriate land. Social and economic policies to promote health are called for, and public health services are to be decentralized, to be integrated, and to foster community participation. Pension plan and social assistance provisions are outlined as are duties of the state in regard to education. The amount of money to be dedicated to education is set out, and a national educational plan is called for to achieve such goals as the eradication of illiteracy, the universalization of school attendance, the improvement of instruction, and the provision of vocational training. Specific measures are set out to protect and preserve the environment. Family policy deals with issues of marriage, the definition of a family, divorce, the right to family planning services, and the deterrence of domestic violence. Social protection provisions cover mothers and children, handicapped persons, and protection of minors. Finally, the customs and rights of Indians are protected, with special provisions given to protect land tenure and to protect the rights of Indians in water resource development and prospecting and mining activities. PMID:12344286

1989-01-01

276

Polity.org: Constitutional Matters  

NSDL National Science Digital Library

Full text of the new South African Constitution, adopted by the Constitutional Assembly on May 8, 1996, and the full text of President Nelson Mandela's address to the Constitutional Assembly upon its adoption, are available via the Web. The constitution is available as a single file, and as plain text, WordPerfect 5.1, 6.1 and Microsoft Word 6.0 .zip files.

1996-01-01

277

Organic constitutions and common law  

Microsoft Academic Search

Constitutions may be viewed as purely political instruments developed by wise and strong leaders and imposed on a loosely\\u000a organized society. The alternate view taken in this paper sees a nation's constitution as being rooted in the norms of individuals\\u000a that form communities and states. Constitutions grow from within; they are not imposed from outside. The history of constitutional\\u000a development

Bruce Yandle

1991-01-01

278

How Capitalistic Is the Constitution?  

ERIC Educational Resources Information Center

|Second in a three-part series designed to help prepare the nation for a thoughtful observance of the Constitutional bicentennial, this publication contains seven essays on the topic of capitalism and the Constitution. "American Democracy and the Acquisitive Spirit" (Marc F. Plattner) supports the argument that the framers of the Constitution

Goldwin, Robert A., Ed.; Schambra, William A., Ed.

279

Methodology for Teaching Constitutional Law  

Microsoft Academic Search

Teaching constitutional law concepts has become more exciting, interesting, and thorough by utilizing Barron, Dienes, McCormack, and Redish's Constitutional Law: Principles and Policy. The authors of this casebook are full professors of law who are distinguished experts in the field of constitutional law. Barron and Dienes are also coauthors of two study aid texts designed to supplement the casebook: a

Constance Frisby Fain

1998-01-01

280

The Constitution and American Diversity.  

ERIC Educational Resources Information Center

Diversity in American constitutional law refers to differences among the laws of the states. However, key phrases in the Constitution have been used to ensure individual rights. The expansion of those rights has led to conflict between community needs and those of the individual, with each side referring to the Constitution for support. (PS)

Glazer, Nathan

1987-01-01

281

How Democratic Is the Constitution?  

ERIC Educational Resources Information Center

|Designed to help prepare the nation for a thoughtful observance of the Constitutional bicentennial, this publication contains seven essays on the topic of democracy and the Constitution. "Democracy and the Constitution" (Gordon S. Wood) looks at the popular and democratic rhetoric used to justify the federalist system in the late 1700's. "Decent,…

Goldwin, Robert A., Ed.; Schambra, William A., Ed.

282

Prophylactic Rules and State Constitutionalism  

Microsoft Academic Search

When the post-Warren Supreme Court began trimming back individual rights, some state courts responded by interpreting analogous or cognate state constitutional provisions to find broader protections, prompting a vigorous debate concerning the legitimacy and interpretive methodology of such state constitutionalism. How can two constitutional provisions, sharing the same language and history, mean different things? This Article looks at that question

Arthur Leavens

2011-01-01

283

Socialist Constitution [1992].  

PubMed

This document contains the text of the Constitution of the Democratic People's Republic of Korea. Chapter 1 sets out the political principles which govern the existence of the state. Chapter 2 outlines the principles of the socialist economy as they apply to the collective and private ownership of property, to meeting the needs of working people, to the technological revolution, to labor regulations (including a minimum working age of 16 years), to development plans, and to external trade. Chapter 3 covers aspects of culture including education, which involves 11-years of compulsory schooling, scholarships to universities and professional schools, and social education. Children of preschool age are enrolled in nurseries and kindergartens at the state's expense. Other issues dealt with in this chapter are the advancement of science and technology, the work of writers and artists, the provision of cultural facilities, protection of the language, the availability of physical fitness facilities, a universal free medical system, and environmental protection. Chapter 4 outlines national defense measures, and chapter 5 sets out the fundamental rights and duties of citizens. This chapter accords women equal social status and rights as men and protects marriage and the family. State institutions (such as the Supreme People's Assembly, the presidency, the National Defense Committee, the Central People's Committee, the Administrative Council, local assemblies and committees, and the court and procurator's office) are discussed in chapter 6. Chapter 7 describes the national emblem and flag and designates Pyongyang as the capital. PMID:12347140

1992-12-15

284

Constitution, 1989. [Selected provisions].  

PubMed

Chapter XII of the Hungarian Constitution, 1989, details the Fundamental Rights and Duties of Citizens. Everyone lawfully within the territory of Hungary has the right to liberty of movement and the freedom to choose his or her residence, except when restricted by law, including the right to leave his or her residence or county. The Republic of Hungary grants asylum to foreign citizens who were persecuted for racial, religious ethnic, linguistic, or political reasons. Men and women shall equally enjoy all civil, political, economic, social and political rights. Mothers are entitled to special care and protection before and after childbirth; women and juveniles are protected at work by special regulations. Every child has the right to special care an assistance from his or her family, the State, and society, for appropriate physical, spiritual, and moral development. Parents shall decide the kind of education their children receive. Hungary grants equal rights to all person within its territories, without regard to race, color, sex, language, religion, political, or other opinion, national, and social origin, property, birth and other status. Prejudicial discrimination shall be severely punished. Everyone has the right to work, to the free choice of employment and profession and to equal pay for equal work. Citizens have the right to social security, including social services necessary in old age, sickness, disability, widowhood, orphanhood an unemployment through no fault of their own. Hungary guarantees the right to culture for its citizens and realized this right by free and compulsory elementary education, by secondary and higher education which is accessible to all on the basis of capacity, and by the financial support of those receiving an education. PMID:12344373

1989-01-01

285

Natural resources - constitutional law  

SciTech Connect

New England Power Co. reaffirms Congressional authority under the commerce clause to regulate interstate trade in natural resources. The Supreme Court has consistently held that states cannot restrict to their own citizens the benefits of natural resources located within state boundaries. As a result, a state's control over such resources is largely limited to taxing their generation or extraction. New England Power Co. reiterates the Court's adamant stand against economic protectionism, especially when natural resources are concerned. Secondarily, this case establishes that Congressional consent to otherwise impermissible state regulation of interstate commerce must be express; the Court will not infer such consent. 29 references.

Jorgensen, C.L.

1983-10-01

286

32 CFR 770.27 - Background.  

Code of Federal Regulations, 2013 CFR

...for Naval Installations in the State of Hawaii § 770.27 Background. (a) Naval installations in Hawaii constitute a significant element...industrial areas within naval installations in Hawaii wherein construction activities and...

2013-07-01

287

OUR FORGOTTEN FOUNDERS: RECONSTRUCTION, PUBLIC EDUCATION, AND CONSTITUTIONAL HEROISM  

Microsoft Academic Search

This Article examines a set of constitutional stories that has not been the subject of focused study by legal scholars—the constitutional stories we tell our schoolchildren. In particular, this Article focuses on portrayals of the Founding and Reconstruction in our most widely-used high school textbooks. These stories offer new clues about the background assumptions that elite lawyers, political leaders, and

Thomas Donnelly

2009-01-01

288

Teaching about the United States Constitution. ERIC Digest No. 12.  

ERIC Educational Resources Information Center

|This publication was prepared as a resource guide to teaching strategies that help students understand the background, nature, and pervasive influence of the U.S. Constitution in the lives of every citizen. As the Constitutional Bicentennial approaches, the focus in many social studies classes increasingly will be on teaching about this most…

Robinson, Sheryl B.

289

Constitutional aneuploidy and cancer predisposition†  

PubMed Central

Constitutional aneuploidies are rare syndromes associated with multiple developmental abnormalities and the alterations in the risk for specific cancers. Acquired somatic chromosomal aneuploidies are the most common genetic aberrations in sporadic cancers. Thus studies of these rare constitutional aneuploidy syndromes are important not only for patient counseling and clinical management, but also for deciphering the mechanisms by which chromosomal aneuploidy affect cancer initiation and progression. Here we review the major constitutional aneuploidy syndromes and suggest some general mechanisms for the associated cancer predisposition.

Ganmore, Ithamar; Smooha, Gil; Izraeli, Shai

2009-01-01

290

The Texas Constitutions Digitization Project  

NSDL National Science Digital Library

Presented by the Tarlton Law Library at the University of Texas School of law, this site offers digital copies of the twelve constitutions of the State (and Republic) of Texas drafted between 1824 and 1876. Both transcriptions and digital images of the original documents are provided, along with a bibliography of printings, a supplemental bibliography, and a link to the relevant Handbook of Texas article. A Spanish version is also available for a few of the constitutions. An internal search engine, an annotated bibliography on the constitutions, a bibliography on Texas constitutional history, and a collection of related links are also provided.

291

Constitutional Issues--Watergate and the Constitution. Teaching with Documents.  

ERIC Educational Resources Information Center

|When U.S. President Richard Nixon resigned in 1974 in the wake of the Watergate scandal, it was only the second time that impeachment of a president had been considered. Although the U.S. Constitution has provisions for a person removed from office to be indicted, there are no guidelines in the Constitution about a President who has resigned. The…

National Archives and Records Administration, Washington, DC.

292

Constitutional afterlife: The continuing impact of Thailand's postpolitical constitution  

Microsoft Academic Search

Thailand's constitution of 1997 introduced profound changes into the country's governance, creating a “postpolitical” democratic structure in which an intricate array of guardian institutions served to limit the role of elected politicians. Ultimately, the constitutional structure was undermined in a military coup against populist billionaire Thaksin Shinawatra, who had taken over many of the institutions designed to constrain political power.

Tom Ginsburg

2009-01-01

293

Constitutional Issues--Watergate and the Constitution. Teaching with Documents.  

ERIC Educational Resources Information Center

When U.S. President Richard Nixon resigned in 1974 in the wake of the Watergate scandal, it was only the second time that impeachment of a president had been considered. Although the U.S. Constitution has provisions for a person removed from office to be indicted, there are no guidelines in the Constitution about a President who has resigned. The…

National Archives and Records Administration, Washington, DC.

294

A gene expression fingerprint of C. elegans embryonic motor neurons  

Microsoft Academic Search

BACKGROUND: Differential gene expression specifies the highly diverse cell types that constitute the nervous system. With its sequenced genome and simple, well-defined neuroanatomy, the nematode C. elegans is a useful model system in which to correlate gene expression with neuron identity. The UNC-4 transcription factor is expressed in thirteen embryonic motor neurons where it specifies axonal morphology and synaptic function.

Rebecca M Fox; Stephen E Von Stetina; Susan J Barlow; Christian Shaffer; Kellen L Olszewski; Jason H Moore; Denis Dupuy; Marc Vidal; David M Miller III

2005-01-01

295

Guidelines for Teaching and Testing the Illinois Constitution.  

ERIC Educational Resources Information Center

|This document sets forth guidelines for teaching and testing public school students on the principles of democratic government as expressed in the Constitution of the United States and the Constitution of the State of Illinois. Identification is made of ways of making the examination required by the state of Illinois not only an integral part of…

Illinois State Office of the Superintendent of Public Instruction, Springfield. Instructional Services Unit.

296

New Constitutive Vectors: Useful Genetic Engineering Tools for Biocatalysis  

PubMed Central

Constitutive vectors are useful tools for genetic engineering. Two constitutive vectors with high levels of expression and broad host ranges were developed and used in a range of Pseudomonas hosts. The vectors showed superior characteristics compared to the inducible vectors as well as the potential to be used as improved genetic tools for biocatalysis.

Xu, Youqiang; Tao, Fei; Xu, Ping

2013-01-01

297

Cleanup Liability and the Constitution  

Microsoft Academic Search

It was observed in the July 1992 issue of this Journal that a plain reading of the Constitution's prohibition on [open quotes][ital ex post facto][close quotes] suggests that some environmental statutes such as the Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (CERCLA or Superfund) and the Resource Conservation and Recovery Act of 1976 (RCRA) conflict with Constitutional principles.

David M. Friedland; Paul E. Hagen

1992-01-01

298

Popular Constitutionalism As Political Law  

Microsoft Academic Search

This Article addresses some of the critical reviews of ‘The People Themselves’, focusing on how they respond to the proposition, which I believe to be correct and made in ‘The People Themselves’, that constitutional law is a distinctive or special kind of law. I call that kind of law political law. Both parts of the formulation are equally important. Constitutional

Mark V. Tushnet

2006-01-01

299

Contributions of Sasang Constitutional Medicine  

Microsoft Academic Search

Sasang Constitutional Medicine (SCM), also referred to as 'integrative medicine', constitutes a unique contribu- tion to the growing field of complementary and alterna- tive medicine. Like all other ancient cultures—including those from India, (Ayurveda) China (TCM), Japan (Kampo), Korea (TKM) and the Mediterranean (TAIM)—there is an emerging fascination with, and indeed use of, these approaches as adjuncts to Western medicine

Edwin L. Cooper

2009-01-01

300

Constitutional Law and Liberal Education.  

ERIC Educational Resources Information Center

By studying constitutional law, students learn about the relationship between democratic theory and practice, one of the main concerns of liberal education. The mind is enlarged when it must apply ethical standards and political ideas to real human problems. How a political science professor teaches constitutional law is discussed. (RM)

Clor, Harry

1985-01-01

301

Reordering American Constitutional Law Teaching.  

ERIC Educational Resources Information Center

Maintains that constitutional law is the cornerstone of an undergraduate public law curriculum. Asserts that there is a welcome trend toward teaching the subject over a two-semester sequence, instead of only one. Describes course content and teaching strategies used in a college constitutional law course. (CFR)

Gerber, Scott D.

1994-01-01

302

Formal State Constitutional Change Processesi  

Microsoft Academic Search

Constitutional change in democracies occurs in two ways: by altering the meaning of the document through interpretation, or by altering the text of the document through amendment or revision. For the United States Constitution, change through interpretation predominates. Review of the extensive experience of the American states with \\

Gerald Benjamin

303

Narratives of the Constitutional Covenant  

Microsoft Academic Search

The constitutional narrative plays perhaps a surprisingly important role in American society. It claims to unfold present judgment from past precedent, according to the doctrine of stare decisis, given an eloquent exposition by the Supreme Court in Planned Parenthood of Southeastern Pennsylvania v. Casey, where the Constitution is referred to as a covenant among generations. Analysis of this and other

Peter Brooks

2012-01-01

304

Developing Standards for Constitutional Change.  

ERIC Educational Resources Information Center

Maintains that the principle of self-restraint that has marked the amending practices since the creation of the U.S. Constitution may be in danger of being forgone. Offers eight standards developed by the Citizens for the Constitution that are designed to weigh the desirability of proposed amendments. (CMK)

Update on Law-Related Education, 1998

1998-01-01

305

How the Constitution Secures Rights.  

ERIC Educational Resources Information Center

|The contributions that George Washington and James Madison made to the creation of the United States Constitution are discussed. As host of the Mount Vernon Conference and president of the Philadelphia Convention, Washington brought to the growing movement for a new constitution great dignity and political stature. Washington's stamp of approval…

Reynolds, William Bradford

306

Transgenic rice as a system to study the stability of transgene expression: multiple heterologous transgenes show similar behaviour in diverse genetic backgrounds  

Microsoft Academic Search

The success of contemporary breeding programmes involving genetic engineering depends on the stability of transgene expression\\u000a over many generations. We studied the stability of transgene expression in 40 independent rice plant lines representing 11\\u000a diverse cultivated varieties. Each line contained three or four different transgenes delivered by particle bombardment, either\\u000a by cotransformation or in the form of a cointegrate vector.

D. Gahakwa; S. B. Maqbool; X. Fu; D. Sudhakar; P. Christou; A. Kohli

2000-01-01

307

GMAX Yeast Background Strain Made from Industrial Tolerant Saccharomyces cerevisiae Engineered to Convert Sucrose, Starch and Cellulosic Sugars Universally to Ethanol Anaerobically with Concurrent Coproduct Expression  

Technology Transfer Automated Retrieval System (TEKTRAN)

Tailored GMAX yeast background strain technology for universal ethanol production industrially. Production of the stable baseline glucose, mannose, arabinose, xylose-utilizing (GMAX) yeast will be evaluated by taking the genes identified in high-throughput screening for a plasmid-based yeast to uti...

308

Constitutively Active Adenosine Monophosphate-Activated Protein Kinase Regulates Voltage-Gated Sodium Channels in Ventricular Myocytes  

Microsoft Academic Search

Background—Some PRKAG2 mutations in the human gene encoding for the-subunit of the adenosine monophosphate- activated protein kinase (AMPK) recently have been shown to cause rhythm disturbances (often fatal) in affected patients. Methods and Results—Rat ventricular myocytes were infected with an adenoviral vector designed to express a truncated constitutively active mutant (T172D) of the AMPK 1-subunit (CA-AMPK). The human cardiac sodium

Peter E. Light; Catriona H. R. Wallace; Jason R. B. Dyck

309

Mice expressing the Swedish APP mutation on a 129 genetic background demonstrate consistent behavioral deficits and pathological markers of Alzheimer's disease  

Microsoft Academic Search

Mutant Tg2576 mice which possess the human “Swedish” APP mutation have been shown to demonstrate both A? plaque pathology and memory deficits in behavioral tasks. These mice are routinely maintained on a mixed C57BL\\/6×SJL genetic background which exhibits a high frequency of retinal degeneration allele and high variability in many behavioral assays. The same APP mutation is also available maintained

Nathan R. Rustay; Elizabeth A. Cronin; Peter Curzon; Stella Markosyan; Robert S. Bitner; Teresa A. Ellis; Jeffrey F. Waring; Michael W. Decker; Lynne E. Rueter; Kaitlin E. Browman

2010-01-01

310

Characterization of an rbcS gene from Nicotiana plumbaginifolia and expression of an rbc SCAT chimeric gene in homologous and heterologous nuclear background  

Microsoft Academic Search

We have cloned a gene (rbcS-8B) encoding the small subunit of ribulose bisphosphate carboxylase from Nicotiana plumbaginifolia and analyzed it with respect to structure and expression. The nucleotide sequence of the rbcS-8B coding region is highly conserved when compared to rbcS sequences from N. tabacum and N. sylvestris. The first two of the three Nicotiana rbcS introns are also well

Carsten Poulsen; Robert Fluhr; John M. Kauffman; Marc Boutry; Nam-Hai Chua

1986-01-01

311

Development of Test Panel of b-Lactamases Expressed in a CommonEscherichia coliHost Background for Evaluation of New b-Lactam Antibiotics  

Microsoft Academic Search

Atestpanelof35different b-lactamasesexpressedinacommonEscherichiacolihostwascreatedtocompare the effect that each b-lactamase had on susceptibility to various b-lactam antibiotics. A comparison of the MICs obtained with this panel generally reflected differences in the substrate profiles of the various b-lacta- mases examined. In addition, several strains of the panel were subjected to selection with porin-specific bacteriophagestoobtainmutantslackingeithertheOmpCorOmpFporinprotein.AmutationineitherOmpC or OmpF did change the susceptibilities of certain strains expressing

PATRICIA A. BRADFORD; ANDCHRISTINE C. SANDERS

312

Constitutional Reform of School Finance.  

ERIC Educational Resources Information Center

This book contains conference papers by experts in educational administration, law, and economics. Six of the papers are devoted to a legal analysis of fiscal inequality among school attendance units, school districts, and States. These contributions are: (1) K. Forbis Jordan and Kern Alexander, "Constitutional Methods of Financing Public…

Alexander, Kern, Ed.; Jordan, K. Forbis, Ed.

313

Constitutive analysis in hot working  

Microsoft Academic Search

Constitutive equations including an Arrhenius term have been commonly applied to steels with the objective of calculating hot rolling and forging forces. The function relating stress and strain rate is generally the hyperbolic-sine since the power and exponential laws lose linearity at high and low stresses, respectively. In austenitic steels, the equations have been used primarily for the peak stress

H. J McQueen; N. D Ryan

2002-01-01

314

A Venture in Constitutional Law.  

ERIC Educational Resources Information Center

Senior high girls and boys from two single-sex schools undertook a study of a Supreme Court case that provided insight not only into constitutional law and history but also into how men and women can work together and relate in other ways than dating. (DS)

Cole, W. Graham; Dillon, Dorothy H.

1980-01-01

315

The Canons of Constitutional Law  

Microsoft Academic Search

Academic and political debates about what texts are canonical in the liberal arts have been occurring for some time. In this Commentary, Professors Balkin and Levinson discuss canons and canonicity in the study of law in general and of constitutional law in particular. Canons, they contend, are not simply collections of texts. Skills, approaches, forms of argument, standard examples, and

Jack M Balkin

1998-01-01

316

Take Advantage of Constitution Day  

ERIC Educational Resources Information Center

|The announcement of the mandate for Constitution and Citizenship Day shortly before September, 2005, probably led to groans of dismay. Not another "must-do" for teachers and schools already stressed by federal and state requirements for standardized tests, increasingly rigid curricula, and scrutiny from the public and officials. But the idea and…

McCune, Bonnie F.

2008-01-01

317

Loss of the Nrf2 transcription factor causes a marked reduction in constitutive and inducible expression of the glutathione S-transferase Gsta1, Gsta2, Gstm1, Gstm2, Gstm3 and Gstm4 genes in the livers of male and female mice.  

PubMed Central

Mice that lack the Nrf2 basic-region leucine-zipper transcription factor are more sensitive than wild-type (WT) animals to the cytotoxic and genotoxic effects of foreign chemicals and oxidants. To determine the basis for the decrease in tolerance of the Nrf2 homozygous null mice to xenobiotics, enzyme assay, Western blotting and gene-specific real-time PCR (TaqMan) have been used to examine the extent to which hepatic expression of GSH-dependent enzymes is influenced by the transcription factor. The amounts of protein and mRNA for class Alpha, Mu and Pi glutathione S-transferases were compared between WT and Nrf2 knockout (KO) mice of both sexes under both constitutive and inducible conditions. Among the class Alpha and class Mu transferases, constitutive expression of Gsta1, Gsta2, Gstm1, Gstm2, Gstm3, Gstm4 and Gstm6 subunits was reduced in the livers of Nrf2 mutant mice to between 3% and 60% of that observed in WT mice. Induction of these subunits by butylated hydroxyanisole (BHA) was more marked in WT female mice than in WT male mice. TaqMan analyses showed the increase in transferase mRNA caused by BHA was attenuated in Nrf2(-/-) mice, with the effect being most apparent in the case of Gsta1, Gstm1 and Gstm3. Amongst class Pi transferase subunits, the constitutive hepatic level of mRNA for Gstp1 and Gstp2 was not substantially affected in the KO mice, but their induction by BHA was dependent on Nrf2; this was more obvious in female mutant mice than in male mice. Nrf2 KO mice exhibited reduced constitutive expression of the glutamate cysteine ligase catalytic subunit, and, to a lesser extent, the expression of glutamate cysteine ligase modifier subunit. Little variation was observed in the levels of glutathione synthase in the different mouse lines. Thus the increased sensitivity of Nrf2(-/-) mice to xenobiotics can be partly attributed to a loss in constitutive expression of multiple GSH-dependent enzymes, which causes a reduction in intrinsic detoxification capacity in the KO animal. These data also indicate that attenuated induction of GSH-dependent enzymes in Nrf2(-/-) mice probably accounts for their failure to adapt to chronic exposure to chemical and oxidative stress.

Chanas, Simon A; Jiang, Qing; McMahon, Michael; McWalter, Gail K; McLellan, Lesley I; Elcombe, Clifford R; Henderson, Colin J; Wolf, C Roland; Moffat, Graeme J; Itoh, Ken; Yamamoto, Masayuki; Hayes, John D

2002-01-01

318

President Mandela Address to Constitutional Assembly  

NSDL National Science Digital Library

Full text of the new South African Constitution, adopted by the Constitutional Assembly on May 8, 1996, and the full text of President Nelson Mandela's address to the Constitutional Assembly upon its adoption, are available via the Web.

Mandela, Nelson, 1918-.

1996-01-01

319

Nongeometric fluxes as supergravity backgrounds  

SciTech Connect

We consider examples of D=4 string theory vacua which, although globally nongeometric, admit a local description in terms of D=10 supergravity backgrounds. We analyze such backgrounds and find that the supersymmetry spinors vary nontrivially along the internal manifold, reproducing the interpolating supergravity solutions found by Frey and Grana. Finally, we propose a simple, local expression for nongeometric fluxes in terms of the internal spinors of the compactification.

Marchesano, Fernando [ASC, Ludwig-Maximilians-Universitaet, Theresienstrasse 37, 80333 Munich (Germany); Schulgin, Waldemar [Max Planck Institut fuer Physik, Foehringer Ring 6, 80805 Munich (Germany)

2007-08-15

320

Function, morphology and protein expression of ageing skeletal muscle: a cross-sectional study of elderly men with different training backgrounds.  

PubMed

The function and morphology of knee extension/m. vastus lateralis and elbow flexion/m. biceps brachii were studied in young (28 +/- 0.1 years, n = 7) and elderly (68 +/- 0.5 years, n = 8) sedentary subjects and in elderly swimmers (69 +/- 1.9 years, n = 6), runners (70 +/- 0.7 years, n = 5) and strength-trained subjects (68 +/- 0.8 years, n = 7). On average, the training groups had, for the 12-17 years before the measurements were taken, performed their training regimen 3 +/- 0.1 times a week. Compared with the young subjects, the maximal isometric torque of the sedentary elderly subjects was 44% (P less than 0.05) lower in knee extension and 32% (P less than 0.05) lower in elbow flexion, and speed of movement was between 20 and 26% (P less than 0.05) lower in both knee extension and elbow flexion. The cross-sectional area of m. quadriceps femoris and the elbow flexors was also 24% (P less than 0.05) and 20% lower respectively, and the specific tension was 27% (P less than 0.05) lower in m. quadriceps femoris and 14% (P less than 0.05) lower in the elbow flexors. A 27% (P less than 0.05) higher content of myosin heavy chain type I and a 39% (P less than 0.05) higher content of the slow-type myosin light chain--2 was observed in m. vastus lateralis of the sedentary elderly subjects as compared with the young subjects. The same tendency was also seen with m. biceps brachii. Since the histochemical fibre-type distribution was identical and no major co-expression of type I and type II myosin heavy-chain isoforms was observed with immunocytochemistry, the increase in slow myosin isoforms with ageing seems mainly related to a larger relative area of type I fibres, induced by a selective atrophy of type II fibre area. An increased content of the beta-isoform of tropomyosin was also demonstrated with ageing. In contrast to the swimmers and runners, the elderly strength-trained subjects had maximal isometric torques, speed of movements, cross-sectional areas, specific tensions and a content of myosin and tropomyosin isoforms in both muscles studied identical to those of the young controls. These results seem to suggest that strength training can counteract the age-related changes in function and morphology of the ageing human skeletal muscle. PMID:2275404

Klitgaard, H; Mantoni, M; Schiaffino, S; Ausoni, S; Gorza, L; Laurent-Winter, C; Schnohr, P; Saltin, B

1990-09-01

321

Elastoplastic finite element analyses of metal deformations using polycrystal constitutive models  

Microsoft Academic Search

A finite element formulation using an elastoplastic polycrystal constitutive theory is presented. The crystal constitutive equations are expressed in an intermediate configuration obtained by unloading the deformed crystal without rotation from the current configuration to a stress-free state through small elastic strains. These constitutive relations and an associated integration procedure are implemented in a pressure-velocity (mixed) finite element formulation. Both

E. B. Marin; P. R. Dawson

1998-01-01

322

Judicial Illumination of the Constitutional \\  

Microsoft Academic Search

Police brutality is one of the most serious and enduring human rights violations in the United States today. One means by which victims may seek redress is under 42 U.S.C. 1983, which provides a civil cause of action against state actors who deprive individuals of their constitutional rights. This Note examines 1983 litigation brought by post-arrest, pretrial detainees alleging the

Eamonn OHagan

2003-01-01

323

Extragalactic Background Radiation  

NASA Astrophysics Data System (ADS)

Contents; Preface; List of participants; 1. Introduction P. J. E. Peebles; 2. Extragalactic gamma-ray background N. Gehrels and C. Cheung; 3. The X-ray background (observations) G. Zamorani; 4. Extragalactic ultraviolet background radiation R. C. Henry and J. Murthy; 5. Ultraviolet background (theory) P. Jakobsen; 6. The optical extragalactic background radiation J. A. Tyson; 7. Infrared background (observations) M. G. Hauser; 8. The infrared background (theory) C. J. Lonsdale; 9. Microwave background radiation (observations) J. C. Mather; 10. Detection of degree scale anisotropy P. M. Lubin; 11. Cosmic microwave background anisotropies and structure formation in the universe N. Vittorio; The radio background emission - the long and short of it M. S. Longair; 13. The radio background: radio-loud galaxies at high and low redshifts J. A. Peacock; 14. Conference summary M. J. Rees.

Calzetti, Daniela; Livio, Mario; Madau, Piero

1995-01-01

324

What is a Twentieth-Century Constitution?  

Microsoft Academic Search

At present, almost all of the constitutions in the world are twentieth-century constitutions; indeed, most of them were not adopted until the second half of the twentieth century. Accordingly, the eighteenth-century Constitution of the United States -- which includes the original constitution of 1787-89; the first ten amendments, adopted in 1791; and the Eleventh Amendment, adopted in 1798 -- antedates

Peter E. Quint

2007-01-01

325

Functional CLOCK is not involved in the entrainment of peripheral clocks to the restricted feeding: entrainable expression of mPer2 and BMAL1 mRNAs in the heart of Clock mutant mice on Jcl:ICR background.  

PubMed

The mammalian circadian timing system consists of a central pacemaker in brain hypothalamus and damping oscillators in most peripheral tissues. To investigate the mechanism that controls circadian rhythms in the mammalian peripheral tissues, we examined the expression rhythm of mPer2, BMAL1, albumin D-site binding protein (DBP), and Rev-erbalpha mRNAs in the heart of homozygous Clock mutant mice on Jcl:ICR background under the temporal feeding restriction. Unexpectedly, the restricted feeding (RF) shifted the circadian phase of both mPer2 and BMAL1 mRNA expressions in the heart not only of wild-type mice but also of Clock mutant mice. Furthermore, in the Clock mutant mice, the amplitude of the circadian expression of mPer2 and BMAL1 mRNAs was dramatically increased by the RF. These data indicate that functional CLOCK is not required for an entrainment of peripheral clocks to RF. On the other hand, the expression levels of DBP and Rev-erbalpha mRNAs were blunted in Clock mutant mice not only under ad libitum but also under RF conditions. Thus, it seems that the rhythmic expression of Rev-erbalpha is not involved in the RF-induced circadian expression of BMAL1 mRNA, although REV-ERBalpha has been identified as a major regulator of BMAL1 transcription. Thus, the entraining mechanism of peripheral tissues to the RF seems to be different from that to the central clock in the suprachiasmatic nucleus. PMID:12387815

Oishi, Katsutaka; Miyazaki, Koyomi; Ishida, Norio

2002-10-25

326

Characterization of the Role of AMP-Activated Protein Kinase in the Regulation of Glucose-Activated Gene Expression Using Constitutively Active and Dominant Negative Forms of the Kinase  

Microsoft Academic Search

In the liver, glucose induces the expression of a number of genes involved in glucose and lipid metabolism, e.g., those encoding L-type pyruvate kinase and fatty acid synthase. Recent evidence has indicated a role for the AMP-activated protein kinase (AMPK) in the inhibition of glucose-activated gene expression in hepatocytes. It remains unclear, however, whether AMPK is involved in the glucose

ANGELA WOODS; DALILA AZZOUT-MARNICHE; MARC FORETZ; SILVIE C. STEIN; PATRICIA LEMARCHAND; PASCAL FERRE ´; FABIENNE FOUFELLE; DAVID CARLING

2000-01-01

327

Constitutive equations for solid propellants  

SciTech Connect

Mechanical behavior of the Space Shuttle redesigned solid rocket motor (RSRM) propellant is studied from a phenomenological point of view. Motivated by the study of the experimental data three initially isotropic constitutive models have been developed. All models represent the effect of strain rate, superimposed hydrostatic pressure, and cyclic loading on the stress and dilatation response of the material. A particular emphasis is given to the prediction of volume dilatation. The model resulting in the best representation of the available data is calibrated using only a few tests. The predictions of the model are compared with experiments for several loading conditions not used in the calibration.

Oezuepek, S.; Becker, E.B. [Univ. of Texas, Austin, TX (United States). Dept. of Aerospace Engineering and Engineering Mechanics

1997-04-01

328

Is the tobacco settlement constitutional?  

PubMed

In August 2005, the Competitive Enterprise Institute (CEI), a conservative advocacy organization, filed a lawsuit in Louisiana challenging the legality of the 1998 Master Settlement Agreement (MSA). The suit alleges that the MSA, under which the states receive monetary payments and the four major tobacco companies are insulated from price competition, violates the Compact Clause and other provisions of the U.S. Constitution. This lawsuit threatens to unravel of one of the most significant opportunities to improve public health in United States history. We consider the merits of the lawsuit, the problems with the MSA that it highlights, and the potential consequences of the suit for public health. PMID:17199817

Rajkumar, Rahul; Gross, Cary P; Forman, Howard P

2006-01-01

329

Constitutive Degradation of Trichloroethylene by an Altered Bacterium in a Gas-Phase Bioreactor.  

National Technical Information Service (NTIS)

Pseudomonas cepacia G4 expresses a unique toluene orth-monooxygenase (Tom) that enables it to degrade toluene and trichloroethylene (TCE). Transposon mutants of G4 have been isolated that constitutively express Tom. Two fixed-film bioreactor designs were ...

M. S. Shields M. J. Reagin R. R. Gerger C. Somerville R. Schaubhut R. Campbell J. Hu-Primmer

1994-01-01

330

Constitutive Expression of the AP-1 Transcription Factors c-jun, junD, junB, and c-fos and the Marginal Zone B-Cell Transcription Factor Notch2 in Splenic Marginal Zone Lymphoma  

PubMed Central

Splenic marginal zone lymphoma (SMZL) is a lymphoma type of putative marginal zone B-cell origin. No specific genetic alterations have yet been demonstrated in SMZL. Clinically, SMZL is a low-grade B-cell non-Hodgkin lymphoma. However, the presence of p53 mutation, 7q22–7q32 deletion or the absence of somatic hypermutations of immunoglobulin genes has been correlated with a worse prognosis. In this study, we analyzed genome-wide gene expression of 24 cases of SMZL using the microarray technique. The AP-1 transcription factors c-jun, junD, junB, and c-fos as well as Notch2 were found to be specifically up-regulated. These data were confirmed by real-time PCR and immunohistochemical staining of tissue sections. The absence of concordant high expression of the MAP kinases, the signaling cascade leading to AP-1 up-regulation, suggests autoregulation of the AP-1 transcription factors and an important role in SMZL oncogenesis. High expression of Notch2, a transcription factor that induces marginal zone B-cell differentiation, is highly suggestive for a marginal zone B-cell origin of SMZL. In addition, SMZL with the 7q deletion showed high expression of TGF-?1 and low expression of the DNA helicase XPB, a crucial part of the nucleotide excision repair complex, possibly explaining the more aggressive clinical course of those cases.

Tr?en, Gunhild; Nygaard, Vigdis; Jenssen, Tor-Kristian; Ikonomou, Ida Munster; Tierens, Anne; Matutes, Estella; Gruszka-Westwood, Alicja; Catovsky, Daniel; Myklebost, Ola; Lauritzsen, Grete; Hovig, Eivind; Delabie, Jan

2004-01-01

331

Constitutive expression of the AP-1 transcription factors c-jun, junD, junB, and c-fos and the marginal zone B-cell transcription factor Notch2 in splenic marginal zone lymphoma.  

PubMed

Splenic marginal zone lymphoma (SMZL) is a lymphoma type of putative marginal zone B-cell origin. No specific genetic alterations have yet been demonstrated in SMZL. Clinically, SMZL is a low-grade B-cell non-Hodgkin lymphoma. However, the presence of p53 mutation, 7q22-7q32 deletion or the absence of somatic hypermutations of immunoglobulin genes has been correlated with a worse prognosis. In this study, we analyzed genome-wide gene expression of 24 cases of SMZL using the microarray technique. The AP-1 transcription factors c-jun, junD, junB, and c-fos as well as Notch2 were found to be specifically up-regulated. These data were confirmed by real-time PCR and immunohistochemical staining of tissue sections. The absence of concordant high expression of the MAP kinases, the signaling cascade leading to AP-1 up-regulation, suggests autoregulation of the AP-1 transcription factors and an important role in SMZL oncogenesis. High expression of Notch2, a transcription factor that induces marginal zone B-cell differentiation, is highly suggestive for a marginal zone B-cell origin of SMZL. In addition, SMZL with the 7q deletion showed high expression of TGF-beta1 and low expression of the DNA helicase XPB, a crucial part of the nucleotide excision repair complex, possibly explaining the more aggressive clinical course of those cases. PMID:15507668

Trřen, Gunhild; Nygaard, Vigdis; Jenssen, Tor-Kristian; Ikonomou, Ida Münster; Tierens, Anne; Matutes, Estella; Gruszka-Westwood, Alicja; Catovsky, Daniel; Myklebost, Ola; Lauritzsen, Grete; Hovig, Eivind; Delabie, Jan

2004-11-01

332

Islam in the Iraqi and Afghan Constitutions: A Comparative Perspective  

Microsoft Academic Search

Much of the controversy that surrounded the development of a constitution in Afghanistan in 2004, and in Iraq in 2005, was over the place and prominence that Islam should assume in the documents and, by extension, the role of religion in the new politics of the two states. This paper begins by providing a short background on the Islamic perspective

Matthew Gray

2007-01-01

333

Unequal Treatment of United States Citizens: Eroding the Constitutional Safeguards  

Microsoft Academic Search

This comment examines the unequal treatment of United States citizens who are labeled enemy combatants by looking at the factual and procedural background of Padilla, Hamdi and Lindh. Next, this comment examines the origins of the label enemy combatant and the constitutional safeguards afforded to criminal defendants in similar situations as Padilla, Hamdi,and Lindh. The terrorist acts Padilla, Hamdi, and

Irma Alicia Cabrera Ramirez

2010-01-01

334

Constitutive expression of catABC genes in the aniline-assimilating bacterium Rhodococcus species AN-22: production, purification, characterization and gene analysis of CatA, CatB and CatC.  

PubMed

The aniline-assimilating bacterium Rhodococcus sp. AN-22 was found to constitutively synthesize CatB (cis,cis-muconate cycloisomerase) and CatC (muconolactone isomerase) in its cells growing on non-aromatic substrates, in addition to the previously reported CatA (catechol 1,2-dioxygenase). The bacterium maintained the specific activity of the three enzymes at an almost equal level during cultivation on succinate. CatB and CatC were purified to homogeneity and characterized. CatB was a monomer with a molecular mass of 44 kDa. The enzyme was activated by Mn2+, Co2+ and Mg2+. Native CatC was a homo-octamer with a molecular mass of 100 kDa. The enzyme was stable between pH 7.0 and 10.5 and was resistant to heating up to 90 degrees C. Genes coding for CatA, CatB and CatC were cloned and named catA, catB and catC respectively. The catABC genes were transcribed as one operon. The deduced amino acid sequences of CatA, CatB and CatC showed high identities with those from other Gram-positive micro-organisms. A regulator gene such as catR encoding a regulatory protein was not observed around the cat gene cluster of Rhodococcus sp. AN-22, but a possible relic of catR was found in the upstream region of catA. Reverse transcriptase-PCR and primer extension analyses showed that the transcriptional start site of the cat gene cluster was located 891 bp upstream of the catA initiation codon in the AN-22 strain growing on both aniline and succinate. Based on these data, we concluded that the bacterium constitutively transcribed the catABC genes and translated its mRNA into CatA, CatB and CatC. PMID:16156722

Matsumura, Eitaro; Sakai, Masashi; Hayashi, Katsuaki; Murakami, Shuichiro; Takenaka, Shinji; Aoki, Kenji

2006-01-01

335

Acetaminophen: Background and Overview  

Center for Biologics Evaluation and Research (CBER)

Text Version1 Acetaminophen: Background and Overview Gerald J. Dal Pan, MD, MHS ... Page 86. 86 Background 1953 NDA 08-717 (acetaminophen tablet) ... More results from www.fda.gov/downloads/advisorycommittees/committeesmeetingmaterials

336

IR Background Suppression Studies.  

National Technical Information Service (NTIS)

A brief description of the background suppression scheme is described, and results obtained using the defocussing technique are presented. It has been demonstrated that a background suppression ratio of two orders of magnitudes can be obtained.

O. Shepherd W. P. Reidy T. F. Zehnpfennig G. A. Vanasse A. T. Stair

1977-01-01

337

Unborn children as constitutional persons.  

PubMed

In Roe v. Wade, the state of Texas argued that "the fetus is a 'person' within the language and meaning of the Fourteenth Amendment." To which Justice Harry Blackmun responded, "If this suggestion of personhood is established, the appellant's case, of course, collapses, for the fetus' right to life would then be guaranteed specifically by the Amendment." However, Justice Blackmun then came to the conclusion "that the word 'person,' as used in the Fourteenth Amendment, does not include the unborn." In this article, it is argued that unborn children are indeed "persons" within the language and meaning of the Fourteenth and Fifth Amendments. As there is no constitutional text explicitly holding unborn children to be, or not to be, "persons," this argument will be based on the "historical understanding and practice, the structure of the Constitution, and thejurisprudence of [the Supreme] Court." Specifically, it is argued that the Constitution does not confer upon the federal government a specifically enumerated power to grant or deny "personhood" under the Fourteenth Amendment. Rather, the power to recognize or deny unborn children as the holders of rights and duties has been historically exercised by the states. The Roe opinion and other Supreme Court cases implicitly recognize this function of state sovereignty. The states did exercise this power and held unborn children to be persons under the property, tort, and criminal law of the several states at the time Roe was decided. As an effect of the unanimity of the states in holding unborn children to be persons under criminal, tort, and property law, the text of the Equal Protection Clause of the Fourteenth Amendment compels federal protection of unborn persons. Furthermore, to the extent Justice Blackmun examined the substantive law in these disciplines, his findings are clearly erroneous and as a whole amount to judicial error. Moreover, as a matter of procedure, according to the due process standards recognized in Fifth Amendment jurisprudence of the Supreme Court, Roe v. Wade should be held null and void as to the rights and interests of unborn persons. PMID:20443281

Roden, Gregory J

2010-01-01

338

A constitutive relation describing the shear-banding transition  

Microsoft Academic Search

An additional contribution to the standard expression for the shear stress must be considered in order to describe shear banding. A possible extension of the standard constitutive relation is proposed. Its physical, purely hydrodynamic origin is discussed. The corresponding Navier-Stokes equation is analyzed for the two-plate geometry, where flow gradients are assumed to exist only in the direction perpendicular to

Jan K. G. Dhont

1999-01-01

339

A constitutive relation describing the shear-banding transition  

Microsoft Academic Search

An additional contribution to the standard expression for the shear stress must be considered in order to describe shear banding. A possible extension of the standard constitutive relation is proposed. Its physical, purely hydrodynamic origin is discussed. The corresponding Navier-Stokes equation is analyzed for the two- plate geometry, where flow gradients are assumed to exist only in the direction perpendicular

Jan K. G. Dhont

1999-01-01

340

The Rehnquist Court, Structural Due Process, and Semisubstantive Constitutional Review  

Microsoft Academic Search

Semisubstantive review, as I use that label, entails four key features. First, the subject matter of judicial inquiry is not the process applied in adjudicating a discrete dispute; rather, the matter at hand is the constitutionality of a statute or other generalized expression of legal policy. Second, some procedural omission by the lawmaker -- rather than an incurably substantive flaw

Dan T. Coenen

2002-01-01

341

Extracting expression modules from perturbational gene expression compendia  

Microsoft Academic Search

Background  Compendia of gene expression profiles under chemical and genetic perturbations constitute an invaluable resource from a systems\\u000a biology perspective. However, the perturbational nature of such data imposes specific challenges on the computational methods\\u000a used to analyze them. In particular, traditional clustering algorithms have difficulties in handling one of the prominent\\u000a features of perturbational compendia, namely partial coexpression relationships between genes.

Steven Maere; Patrick Van Dijck; Martin Kuiper

2008-01-01

342

Constitutively overexpressed 21 kDa protein in Hodgkin lymphoma and aggressive non-Hodgkin lymphomas identified as cytochrome B5b (CYB5B)  

Microsoft Academic Search

BACKGROUND: We have previously reported a novel constitutively overexpressed 21 kDa protein in Hodgkin Lymphoma (HL) and aggressive Non-Hodgkin Lymphomas (NHL). The objective of the current study was to 1) identify this protein using two independent methods, 2) study the expression of the protein and its encoding mRNA in reactive lymph nodes, normal lymphocytes and CD34+ bone marrow precursor cells,

Derek Murphy; Jeremy Parker; Minglong Zhou; Faisal M Fadlelmola; Christian Steidl; Aly Karsan; Randy D Gascoyne; Hong Chen; Diponkar Banerjee

2010-01-01

343

Aboriginal Self-Government through Constitutional Design: A Survey of Fourteen Aboriginal Constitutions in Canada  

Microsoft Academic Search

Despite a rich and diverse literature on the revitalization of Indigenous legal traditions and constitutional orders, no one has yet looked at modern Aboriginal constitutions in Canada. This essay draws upon the comparative constitutional design and Aboriginal politics literatures to describe and analyze the texts of 14 Aboriginal constitutions. The findings suggest that these constitutional documents are similar to non-Aboriginal

Christopher Alcantara; Greg Whitfield

2010-01-01

344

Aboriginal Self-Government through Constitutional Design: A Survey of Fourteen Aboriginal Constitutions in Canada  

Microsoft Academic Search

: Despite a rich and diverse literature on the revitalization of Indigenous legal traditions and constitutional orders, no one has yet looked at modern Aboriginal constitutions in Canada. This essay draws upon the comparative constitutional design and Aboriginal politics literatures to describe and analyze the texts of 14 Aboriginal constitutions. The findings suggest that these constitutional documents are similar to

Christopher Alcantara; Greg Whitfield

2010-01-01

345

RNA editing of the Q/R site of GluA2 in different cultured cell lines that constitutively express different levels of RNA editing enzyme ADAR2.  

PubMed

Adenosine deaminase acting on RNA 2 (ADAR2) catalyzes RNA editing at the glutamine/arginine (Q/R) site of GluA2, and an ADAR2 deficiency may play a role in the death of motor neurons in ALS patients. The expression level of ADAR2 mRNA is a determinant of the editing activity at the GluA2 Q/R site in human brain but not in cultured cells. Therefore, we investigated the extent of Q/R site-editing in the GluA2 mRNA and pre-mRNA as well as the ADAR2 mRNA and GluA2 mRNA and pre-mRNA levels in various cultured cell lines. The extent of the GluA2 mRNA editing was 100% except in SH-SY5Y cells, which have a much lower level of ADAR2 than the other cell lines examined. The ADAR2 activity at the GluA2 pre-mRNA Q/R site correlated with the ADAR2 mRNA level relative to the GluA2 pre-mRNA. SH-SY5Y cells expressed higher level of the GluA2 mRNA in the cytoplasm compared with other cell lines. These results suggest that the ADAR2 expression level reflects editing activity at the GluA2 Q/R site and that although the edited GluA2 pre-mRNA is readily spliced, the unedited GluA2 pre-mRNA is also spliced and transported to the cytoplasm when ADAR2 expression is low. PMID:22366356

Yamashita, Takenari; Tadami, Chieko; Nishimoto, Yoshinori; Hideyama, Takuto; Kimura, Daisuke; Suzuki, Takeshi; Kwak, Shin

2012-02-18

346

Identification and characterization of a constitutively T-loop phosphorylated and active recombinant S6K1: Expression, purification, and enzymatic studies in a high capacity non-radioactive TR-FRET Lance assay  

Microsoft Academic Search

The p70 S6 ribosomal protein kinase 1 (S6K) is a substrate and effector of the mammalian target of rapamycin (mTOR). The mTOR\\/S6K pathway is implicated in cancer and metabolic disorders. To study the molecular regulation of S6K and identify specific inhibitors, availability of active recombinant S6K and robust enzyme assays are critically needed. To date, however, expression of active recombinant

Wei-Guo Zhang; Boris Shor; Ker Yu

2006-01-01

347

Overexpression of c-erbB-2 is related to a higher expression of vascular endothelial growth factor (VEGF) and constitutes an independent prognostic factor in primary node-positive breast cancer after adjuvant systemic treatment.  

PubMed

The aim of this study was to investigate possible associations between the expression of c-erbB-2 and the angiogenic factors vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF), p53 status, routine breast cancer prognostic factors and survival. Expression of c-erbB-2, VEGF, bFGF, and p53 protein was determined with an enzyme-linked immunosorbent assay (ELISA) in 656 patients with primary breast cancer (median follow-up time of 83 months). In 60 cases, we also used immunohistochemistry (IHC) for c-erbB-2 evaluation, to be used as a reference for the ELISA. Overexpression of c-erbB-2 was significantly related to a higher expression of VEGF, lower bFGF content, negative steroid receptor status, and a high S-phase fraction. In multivariate analysis, c-erbB-2 was an independent prognostic factor for relapse-free survival (RFS) and overall survival (OS) in all patients, and in node-positive patients, irrespective of the adjuvant systemic therapy. Combined survival analyses regarding c-erbB-2 and VEGF yielded additional prognostic information. PMID:14687787

Linderholm, B; Andersson, J; Lindh, B; Beckman, L; Erlanson, M; Edin, K; Tavelin, B; Grankvist, K; Henriksson, R

2004-01-01

348

3 CFR 8418 - Proclamation 8418 of September 16, 2009. Constitution Day and Citizenship Day, Constitution Week...  

Code of Federal Regulations, 2010 CFR

...Proclamation The United States Constitution has withstood the...democracy established in our Constitution requires the active participation...its citizenry. Each of us has a responsibility to learn about our Constitution and teach younger...

2010-01-01

349

75 FR 57835 - Constitution Day and Citizenship Day, Constitution Week, 2010  

Federal Register 2010, 2011, 2012, 2013

...Day and Citizenship Day, Constitution Week, 2010 Proclamation 8563--National POW...Day and Citizenship Day, Constitution Week, 2010 By the President of the United States...Citizenship Day, and during Constitution Week, we commemorate the legacy passed...

2010-09-22

350

Growth of hormone-dependent MCF7 breast cancer cells is promoted by constitutive caveolin-1 whose expression is lost in an EGF-R-mediated manner during development of tamoxifen resistance  

Microsoft Academic Search

Caveolin-1 displays both tumour-suppressor and tumour-promoter properties in breast cancer. Using characterised preclinical\\u000a cell models for the transition of oestrogen-sensitive (WT-MCF-7 cells) to a tamoxifen-resistant (TAM-R cells) phenotype we\\u000a examined the role caveolin-1 in the development of hormone-resistant breast cancer. The WT-MCF-7 cells showed abundant expression\\u000a of caveolin-1 which potentiated oestrogen-receptor (ER?) signalling and promoted cell growth despite caveolin-1 mediating

Nicholas B. P. Thomas; Iain R. Hutcheson; Lee Campbell; Julia Gee; Kathryn M. Taylor; Robert I. Nicholson; Mark Gumbleton

2010-01-01

351

Constitutional Law in Twenty Years from Now  

Microsoft Academic Search

The principles of constitutional law as those of many other disciplines seem to develop and to be replaced by new paradigms in the light of globalization. The present article using the genre of constitutional futurology attempts to determine whether this change is real or an illusory impression, and to predict the future of constitutional law and of scholarship reflecting on

András Sajó

2001-01-01

352

Antithetical Ethics: Kenneth Burke and the Constitution.  

ERIC Educational Resources Information Center

|Shows how the textuality of the United States Constitution, the most venerable of classic democratic icons, might be exploited to nurture postmodern ethics. Shows how Kenneth Burke's reading of the Constitution accords with and augments the postmodern theories of J.-F. Lyotard and S. Jarratt. Discusses a postmodern Constitution and the…

Anderson, Virginia

1995-01-01

353

State Constitutional Law: Teaching and Scholarship.  

ERIC Educational Resources Information Center

State constitutional law is an emerging area for legal education, partly because of state supreme court decisions relying on state rather than federal constitutional law. Studying state constitutional law highlights similarities and diversity of legal and governmental systems. Interest in establishment of curricula and materials in state law is…

Williams, Robert F.

1991-01-01

354

The Constitutional Case Against Intracircuit Nonacquiescence  

Microsoft Academic Search

A cornerstone of the United States Constitution is its separation of powers among the legislative, executive, and judicial branches of the national government. The Framers of the Constitution reasoned that separated powers would guard against tyranny by blocking the undue concentration of authority in any single governmental department. In crafting the Constitution, however, the Framers could not anticipate every dispute

Dan T. Coenen

1991-01-01

355

Creep constitutive equations for damaged materials  

Microsoft Academic Search

The object of the present paper is to combine knowledge of microscopic mechanisms with experimental observations to obtain constitutive equations for damaged materials. The initial focus is on the mechanisms of failure in creeping materials. A general structure for the constitutive equations is obtained which gives a framework for the development of constitute equations for particular materials. In the present

A. C. F. Cocks; F. A. Leckie

1987-01-01

356

How Does the Constitution Secure Rights?  

ERIC Educational Resources Information Center

|Third in a series designed to help prepare the nation for a thoughtful observance of the Constitutional bicentennial, this publication presents six essays addressing the issue of human rights and the Constitution. "How the Constitution Protects Our Rights: A Look at the Seminal Years" (Robert A. Rutland) focuses on James Madison's role in…

Goldwin, Robert A., Ed.; Schambra, William A., Ed.

357

Ogden-type constitutive equations in finite elasticity of elastomers  

Microsoft Academic Search

Summary  An explicit expression is derived for the strain energy of a chain under three-dimensional deformation with finite strains.\\u000a For a Gaussian chain, this relation implies the Mooney–Rivlin constitutive law, while for non-Gaussian chains it results in\\u000a novel constitutive equations. Based on a three-chain approximation, a formula is derived for the strain energy of a chain\\u000a with excluded-volume interactions between segments.

A. D. Drozdov; M. Gottlieb

2006-01-01

358

The Cosmic Background Explorer.  

ERIC Educational Resources Information Center

|Outlines the Cosmic Background Explorer (COBE) mission to measure celestial radiation. Describes the instruments used and experiments involving differential microwave radiometers, and a far infrared absolute spectrophotometer. (YP)|

Gulkis, Samuel; And Others

1990-01-01

359

The Cosmic Background Explorer.  

ERIC Educational Resources Information Center

Outlines the Cosmic Background Explorer (COBE) mission to measure celestial radiation. Describes the instruments used and experiments involving differential microwave radiometers, and a far infrared absolute spectrophotometer. (YP)

Gulkis, Samuel; And Others

1990-01-01

360

Background stratospheric aerosol layer  

Microsoft Academic Search

Balloonborne aerosol particle counter measurements are used in studying the stratospheric sulfate layer at Laramie, Wyoming, during 1978 and 1979, a 2-year volcanically quiescent period in which the layer appears to have been in a near equilibrium background state. Subtracting the background aerosol concentration from data obtained during an earlier volcanically active period indicates that the actual decay rate of

D. J. Hofmann; J. M. Rosen

1981-01-01

361

GLAST Background Model.  

National Technical Information Service (NTIS)

In order to estimate the ability of the GLAST/LAT to reject unwanted background of charged particles, optimize the on-board processing, size the required telemetry and optimize the GLAST orbit, we developed a detailed model of the background particles tha...

E. Grove F. Longo J. F. Ormes T. Burnett W. Atwood

2007-01-01

362

Correlators in nontrivial backgrounds  

SciTech Connect

Operators in N=4 super Yang-Mills theory with an R-charge of O(N{sup 2}) are dual to backgrounds which are asymtotically AdS{sub 5}xS{sup 5}. In this article we develop efficient techniques that allow the computation of correlation functions in these backgrounds. We find that (i) contractions between fields in the string words and fields in the operator creating the background are the field theory accounting of the new geometry, (ii) correlation functions of probes in these backgrounds are given by the free field theory contractions but with rescaled propagators and (iii) in these backgrounds there are no open string excitations with their special end point interactions; we have only closed string excitations.

Mello Koch, Robert de [National Institute for Theoretical Physics, Department of Physics and Centre for Theoretical Physics, University of the Witwatersrand, Wits, 2050 (South Africa); Stellenbosch Institute for Advanced Studies, Stellenbosch (South Africa); Ives, Norman; Stephanou, Michael [National Institute for Theoretical Physics, Department of Physics and Centre for Theoretical Physics, University of the Witwatersrand, Wits, 2050 (South Africa)

2009-01-15

363

Sakhalin tender background detailed  

SciTech Connect

This paper reports that on Jan. 27, 1992, the committee constituted by order of the Russian government of Dec. 23, 1991, and headed by V.I. Danilov-Danilyan, the Russian Federation's Minister for Ecology and Natural Resources, assessed the results of a tender announced in May 1991. The tender was for foreign companies to submit feasibility studies for exploration and development of oil and gas on the continental shelf off Sakhalin Island. The announced winner was the MMM group consisting of McDermott International Inc., Marathon Oil Co., and Mitsui and Co. Ltd. In its decision the governmental tender committee (GTC) begged to differ from V. Fedorov, governor of the Territory of Sakhalin, in whose opinion the U.S.-Japanese combine of Exxon Corp.-Sakhalin Oil Development Co. (Sodeco) should have been pronounced winner at the bidding's end. GTC's decision also ran counter to the verdict by a panel of experts constituted by decision of the Examining Council under the Chairman of the Russian Government on Dec. 3, 1991, and headed by F. Salmanov, first deputy Minister of Geology of the U.S.S.R.

Konoplyanik, A. (Russian Federation Ministry for Fuels and Energy (SU))

1992-03-23

364

State Constitutionalism: Completing the Interdisciplinary Study of Constitutional Law and Political Theory.  

ERIC Educational Resources Information Center

Argues that a complete and accurate understanding of constitutional history and constitutional law requires the study of state constitutions. Maintains that state constitutions contain a coherent political theory that is, in important respects, at variance with the concept of federalism. (CFR)

Williams, Robert F.

1993-01-01

365

The GLAST Background Model  

SciTech Connect

In order to estimate the ability of the GLAST/LAT to reject unwanted background of charged particles, optimize the on-board processing, size the required telemetry and optimize the GLAST orbit, we developed a detailed model of the background particles that would affect the LAT. In addition to the well-known components of the cosmic radiation, we included splash and reentrant components of protons, electrons (e+ and e-) from 10 MeV and beyond as well as the albedo gamma rays produced by cosmic ray interactions with the atmosphere. We made estimates of the irreducible background components produced by positrons and hadrons interacting in the multilayered micrometeorite shield and spacecraft surrounding the LAT and note that because the orbital debris has increased, the shielding required and hence the background are larger than were present in EGRET. Improvements to the model are currently being made to include the east-west effect.

Ormes, J.F.; /Denver U.; Atwood, W.; /UC, Santa Cruz; Burnett, T.; /Washington U., Seattle; Grove, E.; /Naval Research Lab, Wash., D.C.; Longo, F.; /INFN, Pisa; McEnery, J.; /NASA, Goddard; Mizuno, T.; /Hiroshima U.; Ritz, S.; /NASA, Goddard

2007-10-17

366

The GLAST Background Model  

SciTech Connect

In order to estimate the ability of the GLAST/LAT to reject unwanted background of charged particles, optimize the on-board processing, size the required telemetry and optimize the GLAST orbit, we developed a detailed model of the background particles that would affect the LAT. In addition to the well-known components of the cosmic radiation, we included splash and reentrant components of protons, electrons (e+ and e-) from 10 MeV and beyond as well as the albedo gamma rays produced by cosmic ray interactions with the atmosphere. We made estimates of the irreducible background components produced by positrons and hadrons interacting in the multilayered micrometeorite shield and spacecraft surrounding the LAT and note that because the orbital debris has increased, the shielding required and hence the background are larger than were present in EGRET. Improvements to the model are currently being made to include the east-west effect.

Ormes, J. F. [University of Denver (United States); Atwood, W. [University of California at Santa Cruz (United States); Burnett, T. [University of Washington (United States); Grove, E. [Naval Research Laboratory (United States); Longo, F. [Instituto Nazionale di Fisica Nucleare (INFN)-Pisa (Italy); McEnery, J.; Ritz, S. [NASA Goddard Space Flight Center (United States); Mizuno, T. [Hiroshima University (Japan)

2007-07-12

367

Constitutional genomic instability, chromosome aberrations in tumor cells and retinoblastoma.  

PubMed

Although retinoblastoma (Rb) is initiated as a result of biallelic inactivation of the RB1 gene, additional genetic events (M3) in tumor cells are indicative of their role in the full transformation of retinal cells. We investigated the constitutional genetic instability by fragile site (FS) expression studies and checked its relationship with loci of tumor cytogenetics in a series of 36 retinoblastoma patients (34 nonfamilial and 2 familial cases). Tumor cytogenetics revealed -13/+13, del/t(13)(q14) (50%), +1/del/t(1p/q) (65%), +6/i(6p) (60%), and del(16)(q13)/(q22 approximately q23) (60%). Conventional cytogenetics in leukocytes revealed constitutional del(13q14) in five unilateral Rb (URB) and one trilateral Rb (TRB). Constitutional del(16)(q22) and t(6;12) were also identified in two cases. Constitutional FS analysis showed a significant increase in the cellular fragility, with high prevalence at 13q14, 3p14, 6p23, 16q22 approximately q23, and 13q22 loci in retinoblastoma patients (P<0.05). Patients with constitutional del(13)(q14) demonstrated higher fragility than those with normal constitution. A strong correlation between loci of constitutional FSs and loci of recurrent chromosomal abnormalities in tumors strengthen and support the proposal that FS loci present as inherent genomic instability in retinoblastoma. The chromosomal changes and resultant genetic mutations, along with RB1 mutation events, probably contribute synergistically to the development and progression of Rb malignancy. Implementation of fluorescence in situ hybridization to nonfamilial Rb on a large scale (113 cases) could detect constitutional RB1 deletion in 12.3% of cases, with equally higher incidence in URB (14.7%) and bilateral Rb (13.6%), demonstrating that the true prevalence of patients with predisposition to RB1 mutation in sporadic URB is definitely higher in our populations. Also, higher incidence of constitutional RB1 deletion mosaicism in unilateral than in bilateral Rb indicates that the constitutional genetic mosaicism in URB should be given serious consideration during genetic counseling. PMID:15041221

Amare Kadam, P S; Ghule, P; Jose, J; Bamne, M; Kurkure, P; Banavali, S; Sarin, R; Advani, S

2004-04-01

368

STAT5 regulation of BCL10 parallels constitutive NF?B activation in lymphoid tumor cells  

PubMed Central

Background Signal Transducer and Activator of Transcription 5 A and B (STAT5) are key survival factors in cells of the lymphoid lineage. Identification of novel, tissue-specific STAT5 regulated genes would advance the ability to combat diseases due to aberrant STAT5 signaling. In the present work a library of human STAT5 bound genomic elements was created and validated. Results Of several STAT5 responsive genomic regulatory elements identified, one was located within the first intron of the human BCL10 gene. Chromatin immuno-precipitation reactions confirmed constitutive in vivo STAT5 binding to this intronic fragment in various human lymphoid tumor cell lines. Interestingly, non-phosphorylated STAT5 was found in the nuclei of Kit225 and YT cells in the absence of cytokine stimulation that paralleled constitutive NF?B activation. Inhibition of the hyperactive JAK3/STAT5 pathway in MT-2 cells via the Mannich-base, NC1153, diminished the constitutive in vivo occupancy of BCL10-SBR by STAT5, reduced NF?B activity and BCL10 protein expression in a dose dependent manner. Moreover, depletion of STAT5 via selective antisense oligonucleotide treatment similarly resulted in decreased BCL10 mRNA and protein expression, cellular viability and impaired NF?B activity independent of IL-2. Conclusion These results suggest that the NF?B regulator BCL10 is an IL-2-independent STAT5 target gene. These findings proffer a model in which un-activated STAT5 can regulate pathways critical for lymphoid cell survival and inhibitors that disrupt STAT5 function independent of tyrosine phosphorylation may be therapeutically effective in treating certain leukemias/lymphomas.

Nagy, Zsuzsanna S; LeBaron, Matthew J; Ross, Jeremy A; Mitra, Abhisek; Rui, Hallgeir; Kirken, Robert A

2009-01-01

369

Covariant constitutive relations and relativistic inhomogeneous plasmas  

SciTech Connect

The notion of a 2-point susceptibility kernel used to describe linear electromagnetic responses of dispersive continuous media in nonrelativistic phenomena is generalized to accommodate the constraints required of a causal formulation in spacetimes with background gravitational fields. In particular the concepts of spatial material inhomogeneity and temporal nonstationarity are formulated within a fully covariant spacetime framework. This framework is illustrated by recasting the Maxwell-Vlasov equations for a collisionless plasma in a form that exposes a 2-point electromagnetic susceptibility kernel in spacetime. This permits the establishment of a perturbative scheme for nonstationary inhomogeneous plasma configurations. Explicit formulae for the perturbed kernel are derived in both the presence and absence of gravitation using the general solution to the relativistic equations of motion of the plasma constituents. In the absence of gravitation this permits an analysis of collisionless damping in terms of a system of integral equations that reduce to standard Landau damping of Langmuir modes when the perturbation refers to a homogeneous stationary plasma configuration. It is concluded that constitutive modeling in terms of a 2-point susceptibility kernel in a covariant spacetime framework offers a natural extension of standard nonrelativistic descriptions of simple media and that its use for describing linear responses of more general dispersive media has wide applicability in relativistic plasma modeling.

Gratus, J.; Tucker, R. W. [Physics Department, Lancaster University, Lancaster, LA1 4YB (United Kingdom) and Cockcroft Institute, Daresbury Laboratory, Daresbury Science and Innovation Campus, Keckwick Lane, Daresbury, Warrington, Cheshire WA4 4AD (United Kingdom)

2011-04-15

370

Morocco and democratic transition: a reading of the constitutional amendments – their context and results  

Microsoft Academic Search

This article, originally delivered in the Fall of 2011 at a seminar held in Beirut at the Centre for Arab Unity Studies, examines the 2011 amendments to the Moroccan Constitution in light of the historical background. The tumultuous events of the so-called ‘Arab Spring’ brought new urgency to the issue of constitutional reforms that had been broached initially on the

Abdelilah Belkeziz

2012-01-01

371

CONSTITUTIONAL DOCUMENTS OF TWO SEPHARDIC COMMUNITIES IN LATIN AMERICA (ARGENTINA AND CUBA)  

Microsoft Academic Search

This is a comparative analysis of the constitutional documents of the Unión Israelita Chevet Ahim of Havana and the Sociedad Comunidad Israelita Sefaradi de Buenos Aires. Both were founded in 1914 by Jews from Turkey coming from a similar background, where the Jewish community was structured as a centralized body and protected by the state. The constitutional documents of these

Margalit Bejarano

1996-01-01

372

New constitutionalism, democratisation and global political economy  

Microsoft Academic Search

Constitutional revision is a feature of the 1990s. Specifically, this involves initiatives to politically ‘lock in’ neo?liberal reforms. These initiatives serve to secure investor freedoms and property rights for transnational enterprises. Yet students of international political economy have paid surprisingly little attention to the constitutional aspects of global restructuring. Thus this essay analyses the new constitutionalism of disciplinary neo?liberalism, understood

Stephen Gill

1998-01-01

373

What Is a Political Constitution&quest  

Microsoft Academic Search

The question—what is a political constitution?—might seem, at first blush, fairly innocuous. At one level, the idea of a political constitution seems fairly well settled, at least insofar as most political constitutionalists subscribe to a similar set of commitments, arguments and assumptions. At a second, more reflective level, however, there remains some doubt whether a political constitution purports to be

Graham Gee; Grégoire C. N. Webber

2010-01-01

374

Sex-associated expression of mouse hepatic and renal CYP2B enzymes by glucocorticoid hormones 1 1 Abbreviations: Dex, dexamethasone; PB, phenobarbital; PCN, pregnenolone-16?-carbonitrile; DDT, 1,1,1-trichloro-2,2-bis( p-chlorophenyl) ethane; P450, cytochrome P450; CAR, constitutive androstane receptor; PBREM, phenobarbital-responsive enhancer module; GR, glucocorticoid receptor; GRE, glucocorticoid-responsive element; PXR, pregnane X receptor; RT–PCR, reverse transcriptase–polymerase chain reaction; GAPDH, glyceraldehyde-3-phosphate dehydrogenase; NR1, nuclear receptor binding site 1; SSC, standard saline citrate; and RXR, retinoid X receptor  

Microsoft Academic Search

The expression of Cyp2b9 and Cyp2b10 genes was investigated in kidney, liver, and cultured hepatocytes of adult C57BL\\/6NCrj mice. The constitutive expression level of CYP2B mRNA in kidney was higher in female than in male mice, as it was in the liver where more CYP2B9 than CYP2B10 was expressed in the females, and more CYP2B10 was expressed in the males.

Kanokwan Jarukamjorn; Tsutomu Sakuma; Makoto Yamamoto; Ayako Ohara; Nobuo Nemoto

2001-01-01

375

Testing of constitutive models in LAME.  

SciTech Connect

Constitutive models for computational solid mechanics codes are in LAME--the Library of Advanced Materials for Engineering. These models describe complex material behavior and are used in our finite deformation solid mechanics codes. To ensure the correct implementation of these models, regression tests have been created for constitutive models in LAME. A selection of these tests is documented here. Constitutive models are an important part of any solid mechanics code. If an analysis code is meant to provide accurate results, the constitutive models that describe the material behavior need to be implemented correctly. Ensuring the correct implementation of constitutive models is the goal of a testing procedure that is used with the Library of Advanced Materials for Engineering (LAME) (see [1] and [2]). A test suite for constitutive models can serve three purposes. First, the test problems provide the constitutive model developer a means to test the model implementation. This is an activity that is always done by any responsible constitutive model developer. Retaining the test problem in a repository where the problem can be run periodically is an excellent means of ensuring that the model continues to behave correctly. A second purpose of a test suite for constitutive models is that it gives application code developers confidence that the constitutive models work correctly. This is extremely important since any analyst that uses an application code for an engineering analysis will associate a constitutive model in LAME with the application code, not LAME. Therefore, ensuring the correct implementation of constitutive models is essential for application code teams. A third purpose of a constitutive model test suite is that it provides analysts with example problems that they can look at to understand the behavior of a specific model. Since the choice of a constitutive model, and the properties that are used in that model, have an enormous effect on the results of an analysis, providing problems that highlight the behavior of various constitutive models to the engineer can be of great benefit. LAME is currently implemented in the Sierra based solid mechanics codes Adagio [3] and Presto [4]. The constitutive models in LAME are available in both codes. Due to the nature of a transient dynamics code--e.g. Presto--it is difficult to test a constitutive model due to inertia effects that show up in the solution. Therefore the testing of constitutive models is primarily done in Adagio. All of the test problems detailed in this report are run in Adagio. It is the goal of the constitutive model test suite to provide a useful service for the constitutive model developer, application code developer and engineer that uses the application code. Due to the conflicting needs and tight time constraints on solid mechanics code development, no requirements exist for implementing test problems for constitutive models. Model developers are strongly encouraged to provide test problems and document those problems, but given the choice of having a model without a test problem or no model at all, certain requirements must be kept loose. A flexible code development environment, especially with regards to research and development in constitutive modeling, is essential to the success of such an environment. This report provides documentation of a number of tests for the constitutive models in LAME. Each section documents a separate test with a brief description of the model, the test problem and the results. This report is meant to be updated periodically as more test problems are created and put into the test suite.

Hammerand, Daniel Carl; Scherzinger, William Mark

2007-09-01

376

Background stratospheric aerosol reference model  

NASA Astrophysics Data System (ADS)

In this analysis, a reference background stratospheric aerosol optical model is developed based on the nearly global SAGE 1 satellite observations in the non-volcanic period from March 1979 to February 1980. Zonally averaged profiles of the 1.0 micron aerosol extinction for the tropics and the mid- and high-altitudes for both hemispheres are obtained and presented in graphical and tabulated form for the different seasons. In addition, analytic expressions for these seasonal global zonal means, as well as the yearly global mean, are determined according to a third order polynomial fit to the vertical profile data set. This proposed background stratospheric aerosol model can be useful in modeling studies of stratospheric aerosols and for simulations of atmospheric radiative transfer and radiance calculations in atmospheric remote sensing.

McCormick, M. P.; Wang, P.

1989-12-01

377

Constitutive Equation for Nematic Liquid Crystals under Weak Velocity Gradient Derived from a Molecular Kinetic Equation  

NASA Astrophysics Data System (ADS)

Constitutive equation for the nematic liquid crystals under weak velocity gradient is derived from the kinetic equation presented by Doi. The constitutive equation is consistent with the phenomenological equation proposed by Ericksen and Leslie. The six viscosity parameters (Leslie coefficients) appearing in the phenomenological theory are expressed by the molecular parameters.

Kuzuu, Nobu; Doi, Masao

1983-10-01

378

Matching Background Color  

NSDL National Science Digital Library

This chapter introduces an especially important subject in the concealment of animals--countershading. One observes many animals with colors that match the general color of their usual backgrounds. Many leaf-eating insects appear green, for example, making them relatively inconspicuous against their normal background of leaves. The manner of coloration that will provide such a color match is not as obvious as one might imagine. It depends significantly on the nature of the lighting. The inquiry-based activities included in this section effectively illustrate this concept.

Ipsen, David; Gillfillan, Gretchen L.; Judy Diamond (Revised New Edition); Judy Scotchmoor (Revised New Edition); Stebbins, Robert

2008-04-01

379

Differential gene expression mediated by 15-hydroxyeicosatetraenoic acid in LPS-stimulated RAW 264.7 cells  

Microsoft Academic Search

BACKGROUND: Given the immuno-modulatory activity of native haemozoin (Hz), the effects of constitutive Hz components on immune response are of interest. Recently, gene expression changes mediated by HNE and the synthetic analogue of Hz, beta-haematin (BH), were identified and implicated a significant role for lipid peroxidation products in Hz's activity. The study presented herein examines gene expression changes in response

Alexandra C Schrimpe; David W Wright

2009-01-01

380

Medroxyprogesterone Acetate Elevation of Nm23-H1 Metastasis Suppressor Expression in Hormone Receptor - Negative Breast Cancer  

Microsoft Academic Search

Background: Reestablishment of metastasis suppressor gene expression may constitute a therapeutic strategy for high- risk breast cancer patients. We previously showed that medroxyprogesterone acetate (MPA), a progestin that has been tested as treatment for advanced breast cancer, ele- vates expression of the Nm23-H1 metastasis suppressor gene in hormone receptor - negative metastatic human breast carcinoma cell lines in vitro via

Diane Palmieri; Douglas O. Halverson; Christine E. Horak; Massimiliano Salerno; Jennifer Johnson; W. Douglas Figg; Melinda Hollingshead; Stephen Hursting; David Berrigan; Seth M. Steinberg; Maria J. Merino; Patricia S. Steeg

381

Contributions of Phonological Memory, Language Comprehension and Hearing to the Expressive Language of Adolescents and Young Adults with Down Syndrome  

ERIC Educational Resources Information Center

|Background: Expressive language constitutes a major challenge to the development of individuals with Down syndrome. This paper investigates the relationships between expressive language abilities, language comprehension and the deficits in verbal short-term memory and hearing which are also associated with the syndrome. Methods: Tests of…

Laws, Glynis

2004-01-01

382

China: Background Notes Series.  

ERIC Educational Resources Information Center

Concise background information on the People's Republic of China is provided. The publication begins with a profile of the country, outlining the people, geography, economy, and membership in international organizations. The bulk of the document then discusses in more detail China's people, geography, history, government, education, economy, and…

Reams, Joanne Reppert

383

Foregrounding the Background.  

ERIC Educational Resources Information Center

Argues that when introductory activities to the classics begin with background information, it can upstage or confine the life of the story, and shows little faith in the students as readers or in the literature itself. Suggests sometimes letting the literature begin, and then helping students make sense of it. Discusses examples from "To Kill a…

Robbins, Bruce

1998-01-01

384

Building Background Knowledge  

ERIC Educational Resources Information Center

|Too often, students enter our classrooms with insufficient knowledge of physical science. As a result, they have a difficult time understanding content in texts, lectures, and laboratory activities. This lack of background knowledge can have an impact on their ability to ask questions and wonder--both key components of inquiry. In this article,…

Fisher, Douglas; Ross, Donna; Grant, Maria

2010-01-01

385

Taiwan: Background Notes Series.  

ERIC Educational Resources Information Center

|Concise background information on Taiwan is provided. The publication begins with a profile of Taiwan, discussing the people, geography, political establishment, and economy. A map of the country is provided. The bulk of the publication then provides more detailed information on Taiwan's people, geography, history, administration, political…

Reams, Joanne Reppert

386

Background Level Care  

Microsoft Academic Search

The framework enabled by the International Caries Detection and Assessment System to allow appropriate, patient-centred caries management includes a frequently encountered scenario in which a comprehensive assessment of the teeth and the patient reveals no lesions in need of active preventive or operative care. The issue addressed here is: what background care is appropriate for patients attending a dental practice

N. B. Pitts

2009-01-01

387

Cosmic background radiation  

Microsoft Academic Search

We summarise the current status of cosmic microwave background spectrum and\\u000aanisotropy measurements, and their theoretical interpretation. This is the\\u000aupdate of the mini-review for the 1997 web-version of the Review of Particle\\u000aProperties.

George Smoot; Douglas Scott

2000-01-01

388

Diffuse UV Background  

NASA Astrophysics Data System (ADS)

We propose a LEGACY project, with the aim of characterizing the diffuse ultraviolet background radiation. In order to achieve maximum impact, we propose to observe exclusively targets for which we already have in hand Voyager diffuse - background spectra (shortward of Lyman alpha). Our Voyager spectroscopy will allow powerful insight into the interpretation and meaning of the deep GALEX images longward of Lyman alpha that we propose (here) to obtain. There is good evidence that a substantial portion of the diffuse UV background at moderate and high Galactic latitudes is exotic in its origin - that is, that the radiation is not simply diffuse galactic light plus the integrated light of distant galaxies. We propose to find clues to the nature and physical origin of the diffuse ultraviolet background radiation in as comprehensive a manner as can be accomplished using GALEX. But in the course of carrying out the proposed work, we will also be creating a permanent GALEX archive of well-chosen deep images that are supported by spectroscopy - images valuable for a wide range of purposes beyond those that we propose. To speed this broader use, we waive all data rights.

Henry, Richard

389

Defending the “private” in constitutional privacy  

Microsoft Academic Search

Suppose we agree to reject the view that privacy has narrow scope and consequently is irrelevant to the constitutional privacy cases. We then have (at least) these two options: (1) We might further emphasize and draw out similarities between tort and constitutional privacy claims in order to develop a notion of privacy fundamental to informational and Fourth Amendment privacy concerns

Judith W. Decew

1987-01-01

390

On constitutive modelling of unsaturated soils  

Microsoft Academic Search

The paper presents a review of constitutive modelling of unsaturated soils. After a brief historical perspective, a number of existing constitutive models are classified and discussed according to the type of stress variables adopted in their formulation. Afterwards, attention is given to recent developments in the proposal of coupled hydraulic-mechanical models and the possibility of casting them in a sound

Antonio Gens; Marcelo Sánchez; Daichao Sheng

2006-01-01

391

The constitutional privacy rights of public employees  

Microsoft Academic Search

Despite the significant expansion of the constitutional rights of public employees during the last three decades, the Supreme Court has proven extremely reluctant to restrict public-sector employment practices on the grounds that they violate the constitutional privacy rights of public employees. This treatment of the privacy rights of public employees is likely to continue because of the Court's formulation of

Robert N. Roberts; Marion T. Doss Jr

1991-01-01

392

Ethnicity and constitutionalism in contemporary Ethiopia  

Microsoft Academic Search

According to the policy of the government of the Ethiopian Peoples' Revolutionary Democratic Front (EPRDF), ethnic identity is the ideological basis of Ethiopia's political organization and administration and as such has been enshrined in the Federal Constitution of December 1994. Yet the Constitution's explicit reinstatement of ethnicity in law coincides with a politico-economic situation which has made ethnoregional groups more

Jon Abbink

1997-01-01

393

A Teacher Reflects on the "Living Constitution".  

ERIC Educational Resources Information Center

|Suggests that the United States Constitution be taught as a product of its times which nonetheless has evolved over the past two centuries. Recommends that secondary school students be required to read the Constitution, with attention to its brevity and generality, and to relate the document to current political affairs. (DMM)|

Smith, Ann R.

1988-01-01

394

The Constitution in the Twentieth Century.  

ERIC Educational Resources Information Center

|Investigates the development of the United States Constitution in the twentieth century up to and including the Burger Court. Contends that interpreting the Constitution is an important issue of our times. Consequently argues that we should teach students about the development of this document. (RKM)|

Murphy, Paul L.

1987-01-01

395

The Educational Significance of Canada's Constitution.  

ERIC Educational Resources Information Center

|Traces the historical relationship of Canada's educational system to its constitution. Concludes that the significance of the patriation of Canada's constitution for education includes strengthening a drive for bilingual education, promoting equality of opportunity, and continuing education as a provincial concern while unifying, nationally, the…

Wells, Allen R.

1985-01-01

396

The Intelligence Function And the Constitution  

Microsoft Academic Search

Strategic intelligence is requisite to national security. But fitting an intelligence function, with its ancillary covert action and counterintelligence activities, into the U.S. constitutional framework is an enduring and perhaps unsolvable problem. Conduct of the government's clandestine operations overseas is an executive function requiring extraordinary secrecy. Yet the Constitution requires that the president share with Congress decisions about intelligence policy,

Harry Howe Ransom

1987-01-01

397

The United States and the Indian Constitution.  

ERIC Educational Resources Information Center

|India, a huge land with the second largest population in the world, socially and economically poor, and culturally and linguistically diverse, became the largest democracy in the world on November 26, 1949 with the adoption of the Indian Constitution. The goals of that constitution are: (1) the achievement of national unity and stability; (2) the…

Weil, Jonathan S.

398

Constitutional Provisions for Community Junior Colleges.  

ERIC Educational Resources Information Center

Examines the role of the federal and state constitutions in community college law. Discusses the lack of state constitutional law pertaining explicitly to these institutions and suggests a probable reason for this void. Gives examples of extant state laws and discusses implications for the community college field. (AYC)

McLeod, Marshall W.

1983-01-01

399

Focus: Foreign Affairs Under the Constitution  

Microsoft Academic Search

Events during the bicentennial year of the United States Constitution focused America's attention on the way in which that document both authorizes and structures an ongoing institutional struggle for dominance in the realm of foreign affairs. As the year progressed, constitutional clashes between the President and Congress spilled across the spectrum of U.S. foreign policymaking-covert operations, warmaking, arms control, foreign

Harold Hongju Koh

1988-01-01

400

Outsourcing the Constitution and Administrative Law Norms  

Microsoft Academic Search

In the United States, the constitutional constraints and administrative law requirements imposed on government agencies generally have no applicability to private entities performing outsourced public administrative activities. In this article, the authors broadly explore the issues associated with outsourcing constitutional and administrative law norms along with government work by imposing them on private contractors. The authors seek to help frame

David H. Rosenbloom; Suzanne J. Piotrowski

2005-01-01

401

Federal Fiscal Constitutions: Risk Sharing and Redistribution  

Microsoft Academic Search

This paper studies the political and economic determinants of regional public transfers. Specifically, it focuses on how such transfers are shaped by alternative fiscal constitutions, where a constitution is an allocation of fiscal instruments across different levels of governments plus a procedure for the collective choice of these instruments. Realistic restrictions on fiscal instruments introduce a trade-off between risk sharing

Torsten Persson; Guido Tabellini

1996-01-01

402

Reverse Incorporation of State Constitutional Law  

Microsoft Academic Search

State supreme courts and the United States Supreme Court are the independent and final arbiters of their respective constitutions, and may therefore take different approaches to analogous state and federal constitutional issues. Such issues arise often, because the documents were modeled on each other and share many of the same guarantees. In answering them, state courts have, as a matter

Joseph Blocher

2011-01-01

403

Nonrecombinant Genetic Modification of Aquifer Bacteria to Achieve Constitutive Degradation of Trichloroethylene.  

National Technical Information Service (NTIS)

Aquifer bacteria were isolated for their capacity to predominate following nutrient enrichment (field application vectors (FAVs)), and screened as hosts for the Tn5 containing, constitutive toluene ortho-monoxygenase (Tom) expressing plasmid: TOM(31c) (wh...

M. S. Shields

1996-01-01

404

Nutrient supplementation with n3 polyunsaturated fatty acids, lutein, and zeaxanthin decrease A2E accumulation and VEGF expression in the retinas of Ccl2/Cx3cr1-deficient mice on Crb1rd8 background.  

PubMed

The Age-Related Eye Diseases Study 2 (AREDS2) clinical trial is assessing the effects of higher dietary xanthophyll (lutein and zeaxanthin) and long-chain n3 polyunsaturated fatty acid (LCPUFA) docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) intake on progression to advanced age-related macular degeneration (AMD). This study's purpose was to examine the retinal effects of the AREDS2 formulation on Chemokine (C-C motif) ligand 2 (Ccl2(-/-))/CX3C chemokine receptor 1 (Cx3cr1(-/-)) mice on Crumbs homolog 1 retinal degeneration phenotype 8 (Crb1(rd8)) background (DKO), which develop focal retinal lesions with certain features similar to AMD. DKO and C57BL/6N rd8 background mice (WT) were bred and randomized into 4 groups. Two groups, WT mice on AREDS2 diet (A-WT) and DKO mice on AREDS2 diet (A-DKO), were supplemented daily with 1.76 ?mol of lutein, 35.1 ?mol of zeaxanthin, 215 ?mol EPA, and 107 ?mol of DHA, and 2 control groups, WT mice on control diet (C-WT) and DKO mice on control diet (C-DKO), were fed an isocaloric diet. All mice had monthly fundus photos and were killed after 3 mo for biochemical and histologic analyses. After 3 mo, 81% of A-DKO mice had lesion regression compared with 25% of C-DKO mice (P < 0.05). Toxic retinal 2-[2,6-dimethyl-8-(2,6,6-trimethyl-1-cyclohexen-1-yl)-1E,3E,5E,7E-octatetra-enyl]-1-(2-hydroxyethyl)-4-[4-methyl-6(2,6,6-trimethyl-1-cyclohexen-1-yl) 1E,3E,5E,7E-hexatrienyl]-pyridinium (A2E) concentrations were significantly lower in A-DKO compared with C-DKO mice. The outer nuclear layer thickness in A-DKO mice was significantly greater than that in C-DKO mice. Retinal expression of inducible nitric oxide synthase (iNos) tumor necrosis factor-? (Tnf-?), Cyclooxygenase-2 (Cox-2), interleukin1beta (IL-1?), and vascular endothelial growth factor (Vegf) was significantly lower in A-DKO compared with C-DKO mice. Xanthophylls and LCPUFAs have antiinflammatory, neuroprotective, and antiangiogenic properties. Our data provide potential mechanisms by which the AREDS2 formula has a protective effect on retinal lesions in DKO mice. PMID:23677863

Ramkumar, Hema L; Tuo, Jingsheng; Shen, De F; Zhang, Jun; Cao, Xiaoguang; Chew, Emily Y; Chan, Chi-Chao

2013-05-15

405

Networks of self-avoiding chains and Ogden-type constitutive equations for elastomers  

Microsoft Academic Search

An expression is derived for the strain energy of a polymer chain under an arbitrary three-dimensional deformation with finite strains. For a Gaussian chain, this expression is reduced to the conventional Moony--Rivlin constitutive law, while for non-Gaussian chains it implies novel constitutive relations. Based on the three-chain approximation, explicit formulas are developed for the strain energy of a chain modeled

A. D. Drozdov; M. Gottlieb

2004-01-01

406

76 FR 58705 - Constitution Day and Citizenship Day, Constitution Week, 2011  

Federal Register 2010, 2011, 2012, 2013

...Constitution Day and Citizenship Day, Constitution Week, 2011 Proclamation 8715--National Employer Support of the Guard and Reserve Week, 2011 Proclamation 8716--National Farm Safety and Health Week, 2011 Proclamation 8717--National...

2011-09-21

407

Transcription of functionally related constitutive genes is not coordinated.  

PubMed

Expression of an individual gene can vary considerably among genetically identical cells because of stochastic fluctuations in transcription. However, proteins comprising essential complexes or pathways have similar abundances and lower variability. It is not known whether coordination in the expression of subunits of essential complexes occurs at the level of transcription, mRNA abundance or protein expression. To directly measure the level of coordination in the expression of genes, we used highly sensitive fluorescence in situ hybridization (FISH) to count individual mRNAs of functionally related and unrelated genes within single Saccharomyces cerevisiae cells. Our results revealed that transcript levels of temporally induced genes are highly correlated in individual cells. In contrast, transcription of constitutive genes encoding essential subunits of complexes is not coordinated because of stochastic fluctuations. The coordination of these functional complexes therefore must occur post-transcriptionally, and likely post-translationally. PMID:21131977

Gandhi, Saumil J; Zenklusen, Daniel; Lionnet, Timothée; Singer, Robert H

2010-12-05

408

Constitutive expression of viral suppressors of PTGS in sugarcane  

Technology Transfer Automated Retrieval System (TEKTRAN)

In our experience, transgenes are silenced by sugarcane at a high frequency. In many cases the silencing is via posttranscriptional gene silencing (PTGS). To understand more about PTGS in sugarcane we are studying the P0 protein of Sugarcane yellow leaf virus (SCYLV) which acts to suppress PTGS. One...

409

Expression and Functional Roles of Angiopoietin-2 in Skeletal Muscles  

Microsoft Academic Search

BackgroundAngiopoietin-1 (ANGPT1) and angiopoietin-2 (ANGPT2) are angiogenesis factors that modulate endothelial cell differentiation, survival and stability. Recent studies have suggested that skeletal muscle precursor cells constitutively express ANGPT1 and adhere to recombinant ANGPT1 and ANGPT2 proteins. It remains unclear whether or not they also express ANGPT2, or if ANGPT2 regulates the myogenesis program of muscle precursors. In this study, ANGPT2

Mahroo Mofarrahi; Sabah N. A. Hussain

2011-01-01

410

The E92K Melanocortin 1 Receptor Mutant Induces cAMP Production and Arrestin Recruitment but Not ERK Activity Indicating Biased Constitutive Signaling  

PubMed Central

Background The melanocortin 1 receptor (MC1R) constitutes a key regulator of melanism. Consequently, many naturally-occurring MC1R mutations are associated with a change in color. An example is the Glu-to-Lys substitution found at position II:20/2.60 in the top of transmembrane helix II which has been identified in melanic mice and several other species. This mutation induces a pronounced increase in MC1R constitutive activity suggesting a link between constitutive activity and melanism which is corroborated by the attenuation of ?-melanocyte stimulating hormone (?MSH) induced activation. However, the mechanism by which the mutation induces constitutive activity is currently not known. Methodology/Principal Findings Here we characterize the constitutive activity, cell surface expression and internalization of the mouse mutant, Mc1r E92K. As previously reported, only positively charged residues at position II:20/2.60 induced an increase in constitutive activity as measured by cAMP accumulation and CREB activation. Furthermore, the mutation induced a constitutive recruitment of ?-arrestin. This phenomenon is only observed in MC1R, however, as the equivalent mutations in MC2-5R had no effect on receptor signaling. Interestingly, the mutation did not induce constitutive ERK1/2 phosphorylation or increase the internalization rate indicating the constitutive activity to be biased. Finally, to identify regions of importance for the increased constitutive activity of Mc1r E92K, we employed a chimeric approach and identified G102 and L110 in the extracellular loop 1 to be selectively important for the constitutive activity as this, but not ?MSH-mediated activation, was abolished upon Ala substitution. Conclusions/Significance It is concluded that the E92K mutation induces an active conformation distinct from that induced by ?MSH and that the extracellular loop 1 is involved in maintaining this conformational state. In turn, the results suggest that in MC1R, which lacks an extracellular loop 2, the first extracellular loop may play a more prominent role during receptor activation than in general.

Benned-Jensen, Tau; Mokrosinski, Jacek; Rosenkilde, Mette M.

2011-01-01

411

Constitutive formation of an RXFP1-signalosome: a novel paradigm in GPCR function and regulation.  

PubMed

The classical second messenger cAMP is important in diverse physiological processes, where its spatial and temporal compartmentalization allows precise control over multiple cellular events. Within this context, G-protein-coupled receptors (GPCRs) govern specialized pools of cAMP, which are functionally specific for the unique cellular effects attributed to a particular system. The relaxin receptor, RXFP1, is a GPCR that exerts pleiotropic physiological effects including a potent anti-fibrotic response, increased cancer metastases, and has efficacy as a vasodilator in heart failure. On a cellular level, relaxin stimulation of RXFP1 results in the activation of multiple G-protein pathways affecting cAMP accumulation. Specificity and diversity in the cAMP signal generated by RXFP1 is controlled by differential G-protein coupling dependent upon the background of cellular expression, and cAMP compartmentalization. Further complexity in cAMP signalling results from the constitutive assembly of an RXFP1-signalosome, which specifically responds to low concentrations of relaxin, and activates a distinct cAMP pathway. The RXFP1-signalosome is a higher-order protein complex that facilitates receptor sensitivity to attomolar concentration of peptide, exhibits constitutive activity and dual coupling to G-proteins and ?-arrestins and reveals a concentration-biased agonism mediated by relaxin. The specific and directed formation of GPCR-centered signalosomes allows an even greater spatial and temporal control of cAMP, thus rationalizing the considerable physiological scope of this ubiquitous second messenger. PMID:21557732

Halls, Michelle L

2012-03-01

412

Who wrote the Constitution and why was it written?  

NSDL National Science Digital Library

Researching the Constitution Use these approved websites to help prove your statement is correct. You do not have to look at all of them. These websites are here to help you research. Read carefully!:) Ben s guide to the Constitution Ben s guide to the Constitution # 2 Constitution Day Constitution for Kids Framers of the Constitution ...

Triola, Ms.

2009-10-13

413

A Nonlinear Constitutive Relationship for Composite Propellants.  

National Technical Information Service (NTIS)

A nonlinear constitutive relationship is developed for uniaxial stress-strain conditions that are shown to fit experimental data over a wide range of strain rates and temperatures. The total stress-strain nonlinearity of particulate filled composites may ...

D. L. Martin

1978-01-01

414

President, Prime Minister, or Constitutional Monarch.  

National Technical Information Service (NTIS)

This paper is divided into three parts: an introduction, a brief statement on the issues of constitutional theory involved, and comments on four recent controversies involving these questions: (1) the Iran-Contra affair; (2) the Intelligence Surveillance ...

E. V. Rostow

1989-01-01

415

Extracting Material Constitutive Parameters from Scattering Parameters.  

National Technical Information Service (NTIS)

In the frequency domain all materials can be described electrically by their complex permittivity (micro) and permeability (micro). These constitutive parameters determine the response of the material to electromagnetic (EM) radiation. The precise knowled...

B. Feng

2006-01-01

416

7 CFR 718.201 - Farm constitution.  

Code of Federal Regulations, 2013 CFR

...identification of land as a farm for the first time and the subsequent reconstitution...of tracts will be divided from the parent farm that currently has land in...properly constituted the previous time; (3) An owner requests in...

2013-01-01

417

New Constitution of Republic of Serbia.  

National Technical Information Service (NTIS)

English text of the new constitution of the Republic of Serbia, originally published in Politika, 10/2/90, declaring Serbia' sovereignty and outlining economic, political, and social rights and responsibilities, as well as describing major governmental or...

1990-01-01

418

Constitutive Equations for Damaged Creeping Materials.  

National Technical Information Service (NTIS)

Constitutive equations for a power-law incompressible isotropic matrix containing aligned facet cracks are presented. Applications are directed to a description of polycrystalline materials which undergo significant tertiary creep when subjected to load a...

G. J. Rodin

1986-01-01

419

Constitutional rights and hypnotically elicited testimony.  

PubMed

Despite the former popularity of hypnosis as a way of "improving" eyewitness memory, many courts almost always regard the use of this testimony to be inadmissible, whereas others allow it only when strict procedural guidelines have been followed. Although the U.S. Supreme Court recognized a defendant's constitutional right to admit his own hypnotically elicited testimony, others have recognized a constitutional basis to exclude hypnotically elicited testimony in most other circumstances. PMID:10212035

Newman, A W; Thompson, J W

1999-01-01

420

Constitutional Change and American Pivotal Politics  

Microsoft Academic Search

Recent studies of legislative gridlock espouse the importance of institutions in separation-of-powers games (Krehbiel 1998; Brady and Volden 2006). However, no study has focused on the greatest institutional change in American political history, the adoption of the U.S. Constitution. This paper makes two contributions. First, it determines whether the Constitution significantly increased or decreased the volume of legislation, while other

Keith L. Dougherty; Justin Moeller