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Sample records for bud dormancy entrance

  1. Bud Dormancy and Growth

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Nearly all land plants produce ancillary meristems in the form of axillary or adventitious buds in addition to the shoot apical meristem. Outgrowth of these buds has a significant impact on plant architecture and the ability of plants to compete with neighboring plants, as well as to respond to and ...

  2. Signals regulating dormancy in vegetative buds

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Dormancy in plants involves a temporary suspension of meristem growth, thus insuring bud survival and maintenance of proper shoot system architecture. Dormancy regulation is a complex process involving interactions of various signals through specific and/or overlapping signal transduction pathways. ...

  3. Current review on signals regulating dormancy in vegetative buds

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Dormancy has been described as a temporary suspension of visible growth of plant structure containing a meristem (Lang et al. 1987). Many vegetative propagules, particularly axillary and adventitious buds require dormancy for over-wintering survival and adequate development. Dormancy regulation is a...

  4. Dormancy induction and release in buds and seeds

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Dormancy is a complex trait in both buds and seeds, which is an important mechanism for survival during the life cycle of plants. Over the years, a vast wealth of information has been generated on how environmental and developmental signals impact dormancy in buds and seeds. At the molecular level, ...

  5. Interaction of chill and heat in peach flower bud dormancy

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Peach bud dormancy requirement is a critical factor in selecting adapted cultivars, but the dormancy process is not well-understood. The Utah model proposes bloom occurs after a cultivar-specific amount of chilling followed by 5000 heat units above 4 °C. This model works well in colder climates, but...

  6. Bud dormancy in perennial plants: a mechanism for survival. In:Dormancy of Cells and Organisms

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Many plants evolved the ability to reproduce asexually through vegetative buds as a survival mechanism. Identifying the genetic and physiological mechanisms regulating dormancy in these reproductive structures will allow manipulation of plant growth and development in both desirable and undesirable ...

  7. Epigenetic regulation of bud dormancy events in perennial plants

    PubMed Central

    Ríos, Gabino; Leida, Carmen; Conejero, Ana; Badenes, María Luisa

    2014-01-01

    Release of bud dormancy in perennial plants resembles vernalization in Arabidopsis thaliana and cereals. In both cases, a certain period of chilling is required for accomplishing the reproductive phase, and several transcription factors with the MADS-box domain perform a central regulatory role in these processes. The expression of DORMANCY-ASSOCIATED MADS-box (DAM)-related genes has been found to be up-regulated in dormant buds of numerous plant species, such as poplar, raspberry, leafy spurge, blackcurrant, Japanese apricot, and peach. Moreover, functional evidence suggests the involvement of DAM genes in the regulation of seasonal dormancy in peach. Recent findings highlight the presence of genome-wide epigenetic modifications related to dormancy events, and more specifically the epigenetic regulation of DAM-related genes in a similar way to FLOWERING LOCUS C, a key integrator of vernalization effectors on flowering initiation in Arabidopsis. We revise the most relevant molecular and genomic contributions in the field of bud dormancy, and discuss the increasing evidence for chromatin modification involvement in the epigenetic regulation of seasonal dormancy cycles in perennial plants. PMID:24917873

  8. [Natural inducing factors of grape bud dormancy and their regulation on respiratory metabolism during dormancy induction].

    PubMed

    Wang, Hai-bo; Wang, Xiao-di; Shi, Xiang-bin; Wang, Bao-liang; Zheng, Xiao-cui; Liu, Feng-zhi

    2015-12-01

    High chilling requirement grape (Vitis vinifera-V. labrusca cv. Summer Black) was used to evaluate its dormancy under short sunlight day (SD), long sunlight day (LD) and natural condition (CK). The results indicated that grape bud dormancy could be induced by natural low temperature and short sunlight alone or together. Short sunlight was the main contributor to the dormancy of grape bud, followed by natural low temperature. SD had more effect on dormancy induction under the same temperature when compared with LD. The grape dormancy induction stopped when the total respiratory rate reached the highest level. During the dormancy induction period, the proportion of pentose phosphate pathway (PPP) operation activity or capacity to total respiratory rate increased from 16.0% to 20.1% or 22.3% to 26.0%, respectively; similarly, the proportion of operation activity or capacity of alternate pathway to total respiratory rate rapidly increased, i.e., from 19.4% to 27.3% or 38.2% to 46.8%. Both low temperature and short sunlight could induce change of respiratory pathway on electron transport chain level. PMID:27112009

  9. Differential Expression of Carbohydrate Metabolism Genes Associated with Bud Dormancy Changes in Leafy Spurge (Euphorbia esula)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Underground adventitious buds of leafy spurge undergo three well-defined phases of dormancy, para-, endo-, and ecodormancy, throughout the year. In this study, relationships between carbohydrate metabolism and bud dormancy were examined and real-time PCR was used to determine if shifts in carbohydra...

  10. Differential expression of carbohydrate metabolism genes during bud dormancy changes in leafy spurge (Euphorbia esula)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Underground adventitious buds of leafy spurge undergo three well-defined phases of dormancy, para-, endo-, and ecodormancy, throughout the year. In this study, relationships between carbohydrate metabolism and bud dormancy were examined and real-time PCR was used to determine if shifts in carbohydra...

  11. Expression of ABA Metabolism-Related Genes Suggests Similarities and Differences Between Seed Dormancy and Bud Dormancy of Peach (Prunus persica)

    PubMed Central

    Wang, Dongling; Gao, Zhenzhen; Du, Peiyong; Xiao, Wei; Tan, Qiuping; Chen, Xiude; Li, Ling; Gao, Dongsheng

    2016-01-01

    Dormancy inhibits seed and bud growth of perennial plants until the environmental conditions are optimal for survival. Previous studies indicated that certain co-regulation pathways exist in seed and bud dormancy. In our study, we found that seed and bud dormancy are similar to some extent but show different reactions to chemical treatments that induce breaking of dormancy. Whether the abscisic acid (ABA) regulatory networks are similar in dormant peach seeds and buds is not well known; however, ABA is generally believed to play a critical role in seed and bud dormancy. In peach, some genes putatively involved in ABA synthesis and catabolism were identified and their expression patterns were studied to learn more about ABA homeostasis and the possible crosstalk between bud dormancy and seed dormancy mechanisms. The analysis demonstrated that two 9-cis-epoxycarotenoid dioxygenase-encoding genes seem to be key in regulating ABA biosynthesis to induce seed and bud dormancy. Three CYP707As play an overlapping role in controlling ABA inactivation, resulting in dormancy-release. In addition, Transcript analysis of ABA metabolism-related genes was much similar demonstrated that ABA pathways was similar in the regulation of vegetative and flower bud dormancy, whereas, expression patterns of ABA metabolism-related genes were different in seed dormancy showed that ABA pathway maybe different in regulating seed dormancy in peach. PMID:26793222

  12. Expression of ABA Metabolism-Related Genes Suggests Similarities and Differences Between Seed Dormancy and Bud Dormancy of Peach (Prunus persica).

    PubMed

    Wang, Dongling; Gao, Zhenzhen; Du, Peiyong; Xiao, Wei; Tan, Qiuping; Chen, Xiude; Li, Ling; Gao, Dongsheng

    2015-01-01

    Dormancy inhibits seed and bud growth of perennial plants until the environmental conditions are optimal for survival. Previous studies indicated that certain co-regulation pathways exist in seed and bud dormancy. In our study, we found that seed and bud dormancy are similar to some extent but show different reactions to chemical treatments that induce breaking of dormancy. Whether the abscisic acid (ABA) regulatory networks are similar in dormant peach seeds and buds is not well known; however, ABA is generally believed to play a critical role in seed and bud dormancy. In peach, some genes putatively involved in ABA synthesis and catabolism were identified and their expression patterns were studied to learn more about ABA homeostasis and the possible crosstalk between bud dormancy and seed dormancy mechanisms. The analysis demonstrated that two 9-cis-epoxycarotenoid dioxygenase-encoding genes seem to be key in regulating ABA biosynthesis to induce seed and bud dormancy. Three CYP707As play an overlapping role in controlling ABA inactivation, resulting in dormancy-release. In addition, Transcript analysis of ABA metabolism-related genes was much similar demonstrated that ABA pathways was similar in the regulation of vegetative and flower bud dormancy, whereas, expression patterns of ABA metabolism-related genes were different in seed dormancy showed that ABA pathway maybe different in regulating seed dormancy in peach. PMID:26793222

  13. Co-ordinated gene expression during phases of dormancy release in raspberry (Rubus idaeus L.) buds.

    PubMed

    Mazzitelli, Luca; Hancock, Robert D; Haupt, Sophie; Walker, Paul G; Pont, Simon D A; McNicol, Jim; Cardle, Linda; Morris, Jenny; Viola, Roberto; Brennan, Rex; Hedley, Peter E; Taylor, Mark A

    2007-01-01

    Bud break in raspberry (Rubus idaeus L.) is often poor and uneven, with many of the subapical buds remaining in a dormant state. In order to determine the dormancy status of raspberry buds, an empirical measure of bud burst in a growth-permissive environment following exposure to chilling (4 degrees C cold storage) was developed. For cv. Glen Ample, percentage bud burst in intact canes and isolated nodes was recorded after 14 d. Isolated nodes (a measure of endodormancy) achieved 100% bud burst after approximately 1500 h chilling whereas buds on intact plants (combined endo- and paradormancy) required an additional 1000 h chilling. A microarray approach was used to follow changes in gene expression that occurred during dormancy transition. The probes for the microarrays were obtained from endodormant and paradormant raspberry bud cDNA libraries. The expression profiles of 5300 clones from these libraries were subjected to principal component analysis to determine the most significant expression patterns. Sequence analysis of these clones, in many cases, enabled their functional categorization and the development of hypotheses concerning the mechanisms of bud dormancy release. Thus a set of novel candidates for key dormancy-related genes from raspberry buds have been identified. Bud dormancy is fundamental to the study of plant developmental processes and, in addition, its regulation is of significant economic importance to fruit and horticultural industries. PMID:17244630

  14. Gibberellins and the break of bud dormancy in virus-infected stem cuttings of Euphorbia pulcherrima.

    PubMed

    Nath, S; Mandahar, C L; Gulati, A

    1979-10-15

    Break in bud dormancy in virus-infected stem cuttings of Euphorbia pulcherrima occurs because of the higher quantity of gibberellins present in them than in healthy cuttings in the dormant period of the plant. PMID:499409

  15. Dormancy regulation in reproductive structures of weedy plants; a comparison between seeds and vegetative buds

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Dormancy in seeds and vegetative buds is one of the key characteristics which allow weedy plants to escape conventional chemical, cultural, mechanical, and bio-control measures currently available to weed managers. Identifying genetic and physiological targets that regulate dormancy induction and re...

  16. Identification of genes associated with bud dormancy release in Prunus persica by suppression subtractive hybridization.

    PubMed

    Leida, Carmen; Terol, Javier; Martí, Gracia; Agustí, Manuel; Llácer, Gerardo; Badenes, María Luisa; Ríos, Gabino

    2010-05-01

    To better understand the molecular and physiological mechanisms underlying maintenance and release of seasonal bud dormancy in perennial trees, we identified differentially expressed genes during dormancy progression in reproductive buds from peach (Prunus persica [L.] Batsch) by suppression subtractive hybridization (SSH) and microarray hybridization. Four SSH libraries were constructed, which were respectively enriched in cDNA highly expressed in dormant buds (named DR), in dormancy-released buds (RD) and in the cultivars with different chilling requirement, 'Zincal 5' (ZS) and 'Springlady' (SZ), sampled after dormancy release. About 2500 clones picked from the four libraries were loaded on a glass microarray. Hybridization of microarrays with the final products of SSH procedure was performed in order to validate the selected clones that were effectively enriched in their respective sample. Nearly 400 positive clones were sequenced, which corresponded to 101 different unigenes with diverse functional annotation. We obtained DAM4, 5 and 6 genes coding for MADS-box transcription factors previously related to growth cessation and terminal bud formation in the evergrowing mutant of peach. Several other cDNAs are similar to dormancy factors described in other species, and others have been related to bud dormancy for the first time in this study. Quantitative reverse transcription polymerase chain reaction analysis confirmed differential expression of cDNAs coding for a Zn-finger transcription factor, a GRAS-like regulator, a DNA-binding protein and proteins similar to forisome subunits involved in the reversible occlusion of sieve elements in Fabaceae, among others. PMID:20231169

  17. Molecular mechanisms underlying the entrance in secondary dormancy of Arabidopsis seeds.

    PubMed

    Ibarra, Silvia E; Tognacca, Rocío S; Dave, Anuja; Graham, Ian A; Sánchez, Rodolfo A; Botto, Javier F

    2016-01-01

    As seasons change, dormant seeds cycle through dormant states until the environmental conditions are favourable for seedling establishment. Dormancy cycle is widespread in the plant kingdom allowing the seeds to display primary and secondary dormancy. Several reports in the last decade have focused on understanding the molecular mechanisms of primary dormancy, but our knowledge regarding secondary dormancy is limited. Here, we studied secondary dormancy induced in Arabidopsis thaliana by incubating seeds at 25 °C in darkness for 4 d. By physiological, pharmacological, expression and genetics approaches, we demonstrate that (1) the entrance in secondary dormancy involves changes in the content and sensitivity to GA, but the content and sensitivity to ABA do not change, albeit ABA is required; (2) RGL2 promotes the entrance in secondary dormancy through ABI5 action; and (3) multivariate analysis with 18 geographical and environmental parameters of accession collection place suggests that temperature is an important variable influencing the induction of secondary dormancy in nature. PMID:26177669

  18. Abscisic acid (ABA) regulates grape bud dormancy, and dormancy release stimuli may act through modification of ABA metabolism

    PubMed Central

    Zheng, Chuanlin; Halaly, Tamar; Acheampong, Atiako Kwame; Takebayashi, Yumiko; Jikumaru, Yusuke; Kamiya, Yuji; Or, Etti

    2015-01-01

    In warm-winter regions, induction of dormancy release by hydrogen cyanamide (HC) is mandatory for commercial table grape production. Induction of respiratory stress by HC leads to dormancy release via an uncharacterized biochemical cascade that could reveal the mechanism underlying this phenomenon. Previous studies proposed a central role for abscisic acid (ABA) in the repression of bud meristem activity, and suggested its removal as a critical step in the HC-induced cascade. In the current study, support for these assumptions was sought. The data show that ABA indeed inhibits dormancy release in grape (Vitis vinifera) buds and attenuates the advancing effect of HC. However, HC-dependent recovery was detected, and was affected by dormancy status. HC reduced VvXERICO and VvNCED transcript levels and induced levels of VvABA8’OH homologues. Regulation of these central players in ABA metabolism correlated with decreased ABA and increased ABA catabolite levels in HC-treated buds. Interestingly, an inhibitor of ethylene signalling attenuated these effects of HC on ABA metabolism. HC also modulated the expression of ABA signalling regulators, in a manner that supports a decreased ABA level and response. Taken together, the data support HC-induced removal of ABA-mediated repression via regulation of ABA metabolism and signalling. Expression profiling during the natural dormancy cycle revealed that at maximal dormancy, the HC-regulated VvNCED1 transcript level starts to drop. In parallel, levels of VvA8H-CYP707A4 transcript and ABA catabolites increase sharply. This may provide initial support for the involvement of ABA metabolism also in the execution of natural dormancy. PMID:25560179

  19. Abscisic acid (ABA) regulates grape bud dormancy, and dormancy release stimuli may act through modification of ABA metabolism.

    PubMed

    Zheng, Chuanlin; Halaly, Tamar; Acheampong, Atiako Kwame; Takebayashi, Yumiko; Jikumaru, Yusuke; Kamiya, Yuji; Or, Etti

    2015-03-01

    In warm-winter regions, induction of dormancy release by hydrogen cyanamide (HC) is mandatory for commercial table grape production. Induction of respiratory stress by HC leads to dormancy release via an uncharacterized biochemical cascade that could reveal the mechanism underlying this phenomenon. Previous studies proposed a central role for abscisic acid (ABA) in the repression of bud meristem activity, and suggested its removal as a critical step in the HC-induced cascade. In the current study, support for these assumptions was sought. The data show that ABA indeed inhibits dormancy release in grape (Vitis vinifera) buds and attenuates the advancing effect of HC. However, HC-dependent recovery was detected, and was affected by dormancy status. HC reduced VvXERICO and VvNCED transcript levels and induced levels of VvABA8'OH homologues. Regulation of these central players in ABA metabolism correlated with decreased ABA and increased ABA catabolite levels in HC-treated buds. Interestingly, an inhibitor of ethylene signalling attenuated these effects of HC on ABA metabolism. HC also modulated the expression of ABA signalling regulators, in a manner that supports a decreased ABA level and response. Taken together, the data support HC-induced removal of ABA-mediated repression via regulation of ABA metabolism and signalling. Expression profiling during the natural dormancy cycle revealed that at maximal dormancy, the HC-regulated VvNCED1 transcript level starts to drop. In parallel, levels of VvA8H-CYP707A4 transcript and ABA catabolites increase sharply. This may provide initial support for the involvement of ABA metabolism also in the execution of natural dormancy. PMID:25560179

  20. Changes in the Expression of Carbohydrate Metabolism Genes during Three Phases of Bud Dormancy in Leafy Spurge

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Underground adventitious buds of leafy spurge (Euphorbia esula) undergo three well-defined phases of dormancy, para-, endo-, and ecodormancy. In this study, relationships among genes involved in carbohydrate metabolism and bud dormancy were examined after paradormancy release (growth induction) by d...

  1. Dormancy-associated MADS-box genes and microRNAs jointly control dormancy transition in pear (Pyrus pyrifolia white pear group) flower bud

    PubMed Central

    Niu, Qingfeng; Li, Jianzhao; Cai, Danying; Qian, Minjie; Jia, Huimin; Bai, Songling; Hussain, Sayed; Liu, Guoqin; Teng, Yuanwen; Zheng, Xiaoyan

    2016-01-01

    Bud dormancy in perennial plants is indispensable to survival over winter and to regrowth and development in the following year. However, the molecular pathways of endo-dormancy induction, maintenance, and release are still unclear, especially in fruit crops. To identify genes with roles in regulating endo-dormancy, 30 MIKCC-type MADS-box genes were identified in the pear genome and characterized. The 30 genes were analysed to determine their phylogenetic relationships with homologous genes, genome locations, gene structure, tissue-specific transcript profiles, and transcriptional patterns during flower bud dormancy in ‘Suli’ pear (Pyrus pyrifolia white pear group). The roles in regulating bud dormancy varied among the MIKC gene family members. Yeast one-hybrid and transient assays showed that PpCBF enhanced PpDAM1 and PpDAM3 transcriptional activity during the induction of dormancy, probably by binding to the C-repeat/DRE binding site, while DAM proteins inhibited the transcriptional activity of PpFT2 during dormancy release. In the small RNA-seq analysis, 185 conserved, 24 less-conserved, and 32 pear-specific miRNAs with distinct expression patterns during bud dormancy were identified. Joint analyses of miRNAs and MIKC genes together with degradome data showed that miR6390 targeted PpDAM transcripts and degraded them to release PpFT2. Our data show that cross-talk among PpCBF, PpDAM, PpFT2, and miR6390 played important roles in regulating endo-dormancy. A model for the molecular mechanism of dormancy transition is proposed: short-term chilling in autumn activates the accumulation of CBF, which directly promotes DAM expression; DAM subsequently inhibits FT expression to induce endo-dormancy, and miR6390 degrades DAM genes to release endo-dormancy. PMID:26466664

  2. Dormancy-associated MADS-box genes and microRNAs jointly control dormancy transition in pear (Pyrus pyrifolia white pear group) flower bud.

    PubMed

    Niu, Qingfeng; Li, Jianzhao; Cai, Danying; Qian, Minjie; Jia, Huimin; Bai, Songling; Hussain, Sayed; Liu, Guoqin; Teng, Yuanwen; Zheng, Xiaoyan

    2016-01-01

    Bud dormancy in perennial plants is indispensable to survival over winter and to regrowth and development in the following year. However, the molecular pathways of endo-dormancy induction, maintenance, and release are still unclear, especially in fruit crops. To identify genes with roles in regulating endo-dormancy, 30 MIKC(C)-type MADS-box genes were identified in the pear genome and characterized. The 30 genes were analysed to determine their phylogenetic relationships with homologous genes, genome locations, gene structure, tissue-specific transcript profiles, and transcriptional patterns during flower bud dormancy in 'Suli' pear (Pyrus pyrifolia white pear group). The roles in regulating bud dormancy varied among the MIKC gene family members. Yeast one-hybrid and transient assays showed that PpCBF enhanced PpDAM1 and PpDAM3 transcriptional activity during the induction of dormancy, probably by binding to the C-repeat/DRE binding site, while DAM proteins inhibited the transcriptional activity of PpFT2 during dormancy release. In the small RNA-seq analysis, 185 conserved, 24 less-conserved, and 32 pear-specific miRNAs with distinct expression patterns during bud dormancy were identified. Joint analyses of miRNAs and MIKC genes together with degradome data showed that miR6390 targeted PpDAM transcripts and degraded them to release PpFT2. Our data show that cross-talk among PpCBF, PpDAM, PpFT2, and miR6390 played important roles in regulating endo-dormancy. A model for the molecular mechanism of dormancy transition is proposed: short-term chilling in autumn activates the accumulation of CBF, which directly promotes DAM expression; DAM subsequently inhibits FT expression to induce endo-dormancy, and miR6390 degrades DAM genes to release endo-dormancy. PMID:26466664

  3. Chilling-Dependent Release of Seed and Bud Dormancy in Peach Associates to Common Changes in Gene Expression

    PubMed Central

    Arbona, Vicent; Gómez-Cadenas, Aurelio; Llácer, Gerardo; Badenes, María Luisa; Ríos, Gabino

    2012-01-01

    Reproductive meristems and embryos display dormancy mechanisms in specialized structures named respectively buds and seeds that arrest the growth of perennial plants until environmental conditions are optimal for survival. Dormancy shows common physiological features in buds and seeds. A genotype-specific period of chilling is usually required to release dormancy by molecular mechanisms that are still poorly understood. In order to find common transcriptional pathways associated to dormancy release, we analyzed the chilling-dependent expression in embryos of certain genes that were previously found related to dormancy in flower buds of peach. We propose the presence of short and long-term dormancy events affecting respectively the germination rate and seedling development by independent mechanisms. Short periods of chilling seem to improve germination in an abscisic acid-dependent manner, whereas the positive effect of longer cold treatments on physiological dwarfing coincides with the accumulation of phenylpropanoids in the seed. PMID:22590512

  4. Slash pine bud dormancy as affected by lifting date and root wrenching in the nursery.

    PubMed

    Kainer, K A; Duryea, M L; White, T L; Johnson, J D

    1991-12-01

    Bud dormancy of root wrenched and unwrenched slash pine (Pinus elliottii Engelm.) seedlings growing in a forest nursery was measured on five lifting dates. Determination of bud dormancy was based on days to budbreak (DBB) under optimal growing conditions, mitotic activity in the apical meristem, chilling hours accumulated, and bud morphology. Based on DBB, seedlings were most dormant at Lift 2 on November 24 after exposure to 189 hours below 10 degrees C and 93 hours below 6.7 degrees C. Mitotic activity in the apical meristem was at its lowest 23 days later at Lift 3, possibly indicating the period when seedlings are most resistant to transplanting stresses. Multiple wrenching resulted in a slight shift in the dormancy cycle as wrenched seedlings set bud sooner in the nursery and broke bud sooner at the planting site in the spring than control seedlings. This implies that wrenched seedlings can be successfully lifted from the nursery earlier and will initiate spring shoot growth earlier than control seedlings. PMID:14972840

  5. Changes in well-defined phases of bud dormancy associated with shifts in carbohydrate metabolism may involve beta-amylases

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Leafy spurge is a noxious perennial weed that infests range lands in the Northern Great Plains. It is being used as a model to investigate dormancy in underground adventitious buds, i.e., root and crown buds. Underground adventitious buds of leafy spurge (Euphorbia esula) are 1) maintained in a quie...

  6. Comparative temporal analyses of the Pinus sylvestris L. var. mongolica litv. apical bud proteome from dormancy to growth.

    PubMed

    Bi, Ying-Dong; Wei, Zhi-Gang; Shen, Zhuo; Lu, Tian-Cong; Cheng, Yu-Xiang; Wang, Bai-Chen; Yang, Chuan-Ping

    2011-02-01

    Bud dormancy in perennial plants adapts to environmental and seasonal changes. Bud dormancy is of ecological interest because it affects forest population growth characteristics and is of economical interest because it impacts wood production levels. To understand Pinus sylvestris L. var. mongolica litv. bud-dormancy and bud-burst mechanisms, we characterized the proteomes of their apical buds at the four critical stages that occur during the dormancy-to-growth transition. Ninety-six proteins with altered expression patterns were identified using NanoLC-ESI-MS/MS. The majority of these proteins (57%) are involved in metabolic and other cellular processes. For 28% of the proteins, a function could not be assigned. However, because their expression levels changed, they may be potential candidate bud development- or dormancy-related proteins. Of the 75 non-redundant bud proteins identified, ascorbate peroxidase, pathogenesis-related protein PR-10, and heat shock proteins dramatically increased during August and November, suggesting that they may involved in the initiation of bud dormancy. Conversely, S-adenosylmethionine synthetase, abscisic acid/stress-induced proteins, superoxide dismutase (SOD), caffeoyl-CoA O-methyltransferase, actin, and type IIIa membrane protein cp-wap13 had greater expression levels during April, suggesting that they may be involved in the initiation of bud dormancy-release. Cell division cycle protein 48 and eukaryotic initiation factors 4A-15 and 4A had greater expression levels during May, suggesting that they may regulate cell proliferate and differentiation in the shoot apical meristem. These observations provide insights into the molecular mechanisms that induce or break bud dormancy. PMID:20373030

  7. Mapping of Candidate Genes Involved in Bud Dormancy and Flowering Time in Sweet Cherry (Prunus avium)

    PubMed Central

    Le Dantec, Loïck; Quero-García, José; Barreneche, Teresa; Wenden, Bénédicte; Dirlewanger, Elisabeth

    2015-01-01

    The timing of flowering in perennial plants is crucial for their survival in temperate climates and is regulated by the duration of bud dormancy. Bud dormancy release and bud break depend on the perception of cumulative chilling during endodormancy and heat during the bud development. The objectives of this work were to identify candidate genes involved in dormancy and flowering processes in sweet cherry, their mapping in two mapping progenies ‘Regina’ × ‘Garnet’ and ‘Regina’ × ‘Lapins’, and to select those candidate genes which co-localized with quantitative trait loci (QTLs) associated with temperature requirements for bud dormancy release and flowering. Based on available data on flowering processes in various species, a list of 79 candidate genes was established. The peach and sweet cherry orthologs were identified and primers were designed to amplify sweet cherry candidate gene fragments. Based on the amplified sequences of the three parents of the mapping progenies, SNPs segregations in the progenies were identified. Thirty five candidate genes were genetically mapped in at least one of the two progenies and all were in silico mapped. Co-localization between candidate genes and QTLs associated with temperature requirements and flowering date were identified for the first time in sweet cherry. The allelic composition of the candidate genes located in the major QTL for heat requirements and flowering date located on linkage group 4 have a significant effect on these two traits indicating their potential use for breeding programs in sweet cherry to select new varieties adapted to putative future climatic conditions. PMID:26587668

  8. Mapping of Candidate Genes Involved in Bud Dormancy and Flowering Time in Sweet Cherry (Prunus avium).

    PubMed

    Castède, Sophie; Campoy, José Antonio; Le Dantec, Loïck; Quero-García, José; Barreneche, Teresa; Wenden, Bénédicte; Dirlewanger, Elisabeth

    2015-01-01

    The timing of flowering in perennial plants is crucial for their survival in temperate climates and is regulated by the duration of bud dormancy. Bud dormancy release and bud break depend on the perception of cumulative chilling during endodormancy and heat during the bud development. The objectives of this work were to identify candidate genes involved in dormancy and flowering processes in sweet cherry, their mapping in two mapping progenies 'Regina' × 'Garnet' and 'Regina' × 'Lapins', and to select those candidate genes which co-localized with quantitative trait loci (QTLs) associated with temperature requirements for bud dormancy release and flowering. Based on available data on flowering processes in various species, a list of 79 candidate genes was established. The peach and sweet cherry orthologs were identified and primers were designed to amplify sweet cherry candidate gene fragments. Based on the amplified sequences of the three parents of the mapping progenies, SNPs segregations in the progenies were identified. Thirty five candidate genes were genetically mapped in at least one of the two progenies and all were in silico mapped. Co-localization between candidate genes and QTLs associated with temperature requirements and flowering date were identified for the first time in sweet cherry. The allelic composition of the candidate genes located in the major QTL for heat requirements and flowering date located on linkage group 4 have a significant effect on these two traits indicating their potential use for breeding programs in sweet cherry to select new varieties adapted to putative future climatic conditions. PMID:26587668

  9. Detection of vegetative bud dormancy QTL in peach

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Most temperate tree species cease growth during the winter and enter a state of endodormancy that requires the exposure of vegetative and floral buds to cold temperatures (below 7°C) to initiate normal growth in the spring. The length of the cold treatment required for the resumption of growth is d...

  10. Transcriptomic analysis of ‘Suli’ pear (Pyrus pyrifolia white pear group) buds during the dormancy by RNA-Seq

    PubMed Central

    2012-01-01

    Background Bud dormancy is a critical developmental process that allows perennial plants to survive unfavorable environmental conditions. Pear is one of the most important deciduous fruit trees in the world, but the mechanisms regulating bud dormancy in this species are unknown. Because genomic information for pear is currently unavailable, transcriptome and digital gene expression data for this species would be valuable resources to better understand the molecular and biological mechanisms regulating its bud dormancy. Results We performed de novo transcriptome assembly and digital gene expression (DGE) profiling analyses of ‘Suli’ pear (Pyrus pyrifolia white pear group) using the Illumina RNA-seq system. RNA-Seq generated approximately 100 M high-quality reads that were assembled into 69,393 unigenes (mean length = 853 bp), including 14,531 clusters and 34,194 singletons. A total of 51,448 (74.1%) unigenes were annotated using public protein databases with a cut-off E-value above 10-5. We mainly compared gene expression levels at four time-points during bud dormancy. Between Nov. 15 and Dec. 15, Dec. 15 and Jan. 15, and Jan. 15 and Feb. 15, 1,978, 1,024, and 3,468 genes were differentially expressed, respectively. Hierarchical clustering analysis arranged 190 significantly differentially-expressed genes into seven groups. Seven genes were randomly selected to confirm their expression levels using quantitative real-time PCR. Conclusions The new transcriptomes offer comprehensive sequence and DGE profiling data for a dynamic view of transcriptomic variation during bud dormancy in pear. These data provided a basis for future studies of metabolism during bud dormancy in non-model but economically-important perennial species. PMID:23234335

  11. Transcriptional profiling of bud dormancy induction and release in oak by next-generation sequencing

    PubMed Central

    2013-01-01

    Background In temperate regions, the time lag between vegetative bud burst and bud set determines the duration of the growing season of trees (i.e. the duration of wood biomass production). Dormancy, the period during which the plant is not growing, allows trees to avoid cold injury resulting from exposure to low temperatures. An understanding of the molecular machinery controlling the shift between these two phenological states is of key importance in the context of climatic change. The objective of this study was to identify genes upregulated during endo- and ecodormancy, the two main stages of bud dormancy. Sessile oak is a widely distributed European white oak species. A forcing test on young trees was first carried out to identify the period most likely to correspond to these two stages. Total RNA was then extracted from apical buds displaying endo- and ecodormancy. This RNA was used for the generation of cDNA libraries, and in-depth transcriptome characterization was performed with 454 FLX pyrosequencing technology. Results Pyrosequencing produced a total of 495,915 reads. The data were cleaned, duplicated reads removed, and sequences were mapped onto the oak UniGene data. Digital gene expression analysis was performed, with both R statistics and the R-Bioconductor packages (edgeR and DESeq), on 6,471 contigs with read numbers ≥ 5 within any contigs. The number of sequences displaying significant differences in expression level (read abundance) between endo- and ecodormancy conditions ranged from 75 to 161, depending on the algorithm used. 13 genes displaying significant differences between conditions were selected for further analysis, and 11 of these genes, including those for glutathione-S-transferase (GST) and dehydrin xero2 (XERO2) were validated by quantitative PCR. Conclusions The identification and functional annotation of differentially expressed genes involved in the “response to abscisic acid”, “response to cold stress” and “response to oxidative stress” categories constitutes a major step towards characterization of the molecular network underlying vegetative bud dormancy, an important life history trait of long-lived organisms. PMID:23575249

  12. Genome-wide identification of WRKY family genes in peach and analysis of WRKY expression during bud dormancy.

    PubMed

    Chen, Min; Tan, Qiuping; Sun, Mingyue; Li, Dongmei; Fu, Xiling; Chen, Xiude; Xiao, Wei; Li, Ling; Gao, Dongsheng

    2016-06-01

    Bud dormancy in deciduous fruit trees is an important adaptive mechanism for their survival in cold climates. The WRKY genes participate in several developmental and physiological processes, including dormancy. However, the dormancy mechanisms of WRKY genes have not been studied in detail. We conducted a genome-wide analysis and identified 58 WRKY genes in peach. These putative genes were located on all eight chromosomes. In bioinformatics analyses, we compared the sequences of WRKY genes from peach, rice, and Arabidopsis. In a cluster analysis, the gene sequences formed three groups, of which group II was further divided into five subgroups. Gene structure was highly conserved within each group, especially in groups IId and III. Gene expression analyses by qRT-PCR showed that WRKY genes showed different expression patterns in peach buds during dormancy. The mean expression levels of six WRKY genes (Prupe.6G286000, Prupe.1G393000, Prupe.1G114800, Prupe.1G071400, Prupe.2G185100, and Prupe.2G307400) increased during endodormancy and decreased during ecodormancy, indicating that these six WRKY genes may play a role in dormancy in a perennial fruit tree. This information will be useful for selecting fruit trees with desirable dormancy characteristics or for manipulating dormancy in genetic engineering programs. PMID:26951048

  13. Extensive Transcriptome Changes During Natural Onset and Release of Vegetative Bud Dormancy in Populus

    PubMed Central

    Howe, Glenn T.; Horvath, David P.; Dharmawardhana, Palitha; Priest, Henry D.; Mockler, Todd C.; Strauss, Steven H.

    2015-01-01

    To survive winter, many perennial plants become endodormant, a state of suspended growth maintained even in favorable growing environments. To understand vegetative bud endodormancy, we collected paradormant, endodormant, and ecodormant axillary buds from Populus trees growing under natural conditions. Of 44,441 Populus gene models analyzed using NimbleGen microarrays, we found that 1,362 (3.1%) were differentially expressed among the three dormancy states, and 429 (1.0%) were differentially expressed during only one of the two dormancy transitions (FDR p-value < 0.05). Of all differentially expressed genes, 69% were down-regulated from paradormancy to endodormancy, which was expected given the lower metabolic activity associated with endodormancy. Dormancy transitions were accompanied by changes in genes associated with DNA methylation (via RNA-directed DNA methylation) and histone modifications (via Polycomb Repressive Complex 2), confirming and extending knowledge of chromatin modifications as major features of dormancy transitions. Among the chromatin-associated genes, two genes similar to SPT (SUPPRESSOR OF TY) were strongly up-regulated during endodormancy. Transcription factor genes and gene sets that were atypically up-regulated during endodormancy include a gene that seems to encode a trihelix transcription factor and genes associated with proteins involved in responses to ethylene, cold, and other abiotic stresses. These latter transcription factors include ETHYLENE INSENSITIVE 3 (EIN3), ETHYLENE-RESPONSIVE ELEMENT BINDING PROTEIN (EBP), ETHYLENE RESPONSE FACTOR (ERF), ZINC FINGER PROTEIN 10 (ZAT10), ZAT12, and WRKY DNA-binding domain proteins. Analyses of phytohormone-associated genes suggest important changes in responses to ethylene, auxin, and brassinosteroids occur during endodormancy. We found weaker evidence for changes in genes associated with salicylic acid and jasmonic acid, and little evidence for important changes in genes associated with gibberellins, abscisic acid, and cytokinin. We identified 315 upstream sequence motifs associated with eight patterns of gene expression, including novel motifs and motifs associated with the circadian clock and responses to photoperiod, cold, dehydration, and ABA. Analogies between flowering and endodormancy suggest important roles for genes similar to SQUAMOSA-PROMOTER BINDING PROTEIN-LIKE (SPL), DORMANCY ASSOCIATED MADS-BOX (DAM), and SUPPRESSOR OF OVEREXPRESSION OF CONSTANS 1 (SOC1). PMID:26734012

  14. Differentiated dynamics of bud dormancy and growth in temperate fruit trees relating to bud phenology adaptation, the case of apple and almond trees

    NASA Astrophysics Data System (ADS)

    El Yaacoubi, Adnane; Malagi, Gustavo; Oukabli, Ahmed; Citadin, Idemir; Hafidi, Majida; Bonhomme, Marc; Legave, Jean-Michel

    2016-04-01

    Few studies have focused on the characterization of bud dormancy and growth dynamics for temperate fruit species in temperate and mild cropping areas, although this is an appropriate framework to anticipate phenology adaptation facing future warming contexts which would potentially combine chill declines and heat increases. To examine this issue, two experimental approaches and field observations were used for high- and low-chill apple cultivars in temperate climate of southern France and in mild climates of northern Morocco and southern Brazil. Low-chill almond cultivars offered an additional relevant plant material for comparison with apple in northern Morocco. Divergent patterns of dormancy and growth dynamics were clearly found in apple tree between southern France and southern Brazil. Divergences were less pronounced between France and Morocco. A global view outlined main differences in the dormancy chronology and intensity, the transition between endordormancy and ecodormancy and the duration of ecodormancy. A key role of bud rehydration in the transition period was shown. High-chill cultivars would be submitted in mild conditions to heterogeneous rehydration capacities linked to insufficient chill fulfillment and excessive forcing linked to high temperatures. This would favor bud competitions and consequently excessive flowering durations and weak flowering. Low chilling requirements in apple and almond would conversely confer biological capacities to tolerate superficial dormancy and abrupt transition from endordormancy to ecodormancy without important heterogeneous rehydration states within buds. It may also assume that low-chill cultivars can also tolerate high temperatures during ecodormancy as well as extended flowering durations.

  15. EARLY BUD-BREAK 1 (EBB1) is a regulator of release from seasonal dormancy in poplar trees.

    PubMed

    Yordanov, Yordan S; Ma, Cathleen; Strauss, Steven H; Busov, Victor B

    2014-07-01

    Trees from temperate latitudes transition between growth and dormancy to survive dehydration and freezing stress during winter months. We used activation tagging to isolate a dominant mutation affecting release from dormancy and identified the corresponding gene EARLY BUD-BREAK 1 (EBB1). We demonstrate through positioning of the tag, expression analysis, and retransformation experiments that EBB1 encodes a putative APETALA2/Ethylene responsive factor transcription factor. Transgenic up-regulation of the gene caused early bud-flush, whereas down-regulation delayed bud-break. Native EBB1 expression was highest in actively growing apices, undetectable during the dormancy period, but rapidly increased before bud-break. The EBB1 transcript was localized in the L1/L2 layers of the shoot meristem and leaf primordia. EBB1-overexpressing transgenic plants displayed enlarged shoot meristems, open and poorly differentiated buds, and a higher rate of cell division in the apex. Transcriptome analyses of the EBB1 transgenics identified 971 differentially expressed genes whose expression correlated with the EBB1 expression changes in the transgenic plants. Promoter analysis among the differentially expressed genes for the presence of a canonical EBB1-binding site identified 65 putative target genes, indicative of a broad regulatory context of EBB1 function. Our results suggest that EBB1 has a major and integrative role in reactivation of meristem activity after winter dormancy. PMID:24951507

  16. Comparative proteomic and transcriptomic approaches to address the active role of GA4 in Japanese apricot flower bud dormancy release

    PubMed Central

    Zhuang, Weibing; Gao, Zhihong; Zhang, Zhen

    2013-01-01

    Hormones are closely associated with dormancy in deciduous fruit trees, and gibberellins (GAs) are known to be particularly important. In this study, we observed that GA4 treatment led to earlier bud break in Japanese apricot. To understand better the promoting effect of GA4 on the dormancy release of Japanese apricot flower buds, proteomic and transcriptomic approaches were used to analyse the mechanisms of dormancy release following GA4 treatment, based on two-dimensional gel electrophoresis (2-DE) and digital gene expression (DGE) profiling, respectively. More than 600 highly reproducible protein spots (P<0.05) were detected and, following GA4 treatment, 38 protein spots showed more than a 2-fold difference in expression, and 32 protein spots were confidently identified according to the databases. Compared with water treatment, many proteins that were associated with energy metabolism and oxidationreduction showed significant changes after GA4 treatment, which might promote dormancy release. We observed that genes at the mRNA level associated with energy metabolism and oxidationreduction also played an important role in this process. Analysis of the functions of the identified proteins and genes and the related metabolic pathways would provide a comprehensive proteomic and transcriptomic view of the coordination of dormancy release after GA4 treatment in Japanese apricot flower buds. PMID:24014872

  17. [Relationships between H2O2 metabolism and Ca2+ transport in dormancy-breaking process of nectarine floral buds].

    PubMed

    Tan, Yue; Gao, Dong-sheng; Li, Ling; Wei, Hai-rong; Wang, Jia-wei; Liu, Qing-zhong

    2015-02-01

    In order to explore regulatory function of H2O2 in bud dormancy release, main effects of three dormancy-breaking treatments (high temperature, hydrogen cyanamide and TDZ) on H2O2 metabolism were determined, and impacts of H2O2 on Ca2+ transport were tested using non-invasive micro-test technique. The results showed that both high temperature and hydrogen cyanamide induced H2O2 accumulation and CAT inhibition were efficient in breaking dormancy during deep dormancy period. However, TDZ showed little impacts on H2O2 metabolism and was much less effective in breaking dormancy. Dormant floral primordium was absorbing state to exogenous Ca2+ due to active calcium channels. The Ca2+ transport could be changed by exogenous H2O2. H2O2 of low concentration reduced the absorption rate of Ca2+, and at high concentration, it changed the Ca2+ transport direction from absorption to release. The results indicated that H2O2 signals were related with Ca2+ signals in dormant buds. Ca2+ signal regulated by H2O2 accumulation might be important in the dormancy-breaking signal transduction process induced by high temperature and hydrogen cyanamide. PMID:26094456

  18. TRANSCRIPTOME ANALYSIS OF LEAFY SPURGE (EUPHORBIA ESULA L.) CROWN BUDS DURING SHIFTS IN WELL-DEFINED PHASES OF DORMANCY

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Microarray analysis was used to follow changes in gene expression coinciding with seasonal changes in the dormancy status of crown buds of field-grown leafy spurge. Known cold-regulated genes were induced and numerous GA-responsive genes were down-regulated during the transition from paradormancy to...

  19. The Gentio-Oligosaccharide Gentiobiose Functions in the Modulation of Bud Dormancy in the Herbaceous Perennial Gentiana[C][W

    PubMed Central

    Takahashi, Hideyuki; Imamura, Tomohiro; Konno, Naotake; Takeda, Takumi; Fujita, Kohei; Konishi, Teruko; Nishihara, Masahiro; Uchimiya, Hirofumi

    2014-01-01

    Bud dormancy is an adaptive strategy that perennials use to survive unfavorable conditions. Gentians (Gentiana), popular alpine flowers and ornamentals, produce overwintering buds (OWBs) that can persist through the winter, but the mechanisms regulating dormancy are currently unclear. In this study, we conducted targeted metabolome analysis to obtain clues about the metabolic mechanisms involved in regulating OWB dormancy. Multivariate analysis of metabolite profiles revealed metabolite patterns characteristic of dormant states. The concentrations of gentiobiose [β-d-Glcp-(1→6)-d-Glc] and gentianose [β-d-Glcp-(1→6)-d-Glc-(1→2)-d-Fru] significantly varied depending on the stage of OWB dormancy, and the gentiobiose concentration increased prior to budbreak. Both activation of invertase and inactivation of β-glucosidase resulted in gentiobiose accumulation in ecodormant OWBs, suggesting that gentiobiose is seldom used as an energy source but is involved in signaling pathways. Furthermore, treatment with exogenous gentiobiose induced budbreak in OWBs cultured in vitro, with increased concentrations of sulfur-containing amino acids, GSH, and ascorbate (AsA), as well as increased expression levels of the corresponding genes. Inhibition of GSH synthesis suppressed gentiobiose-induced budbreak accompanied by decreases in GSH and AsA concentrations and redox status. These results indicate that gentiobiose, a rare disaccharide, acts as a signal for dormancy release of gentian OWBs through the AsA-GSH cycle. PMID:25326293

  20. The gentio-oligosaccharide gentiobiose functions in the modulation of bud dormancy in the herbaceous perennial Gentiana.

    PubMed

    Takahashi, Hideyuki; Imamura, Tomohiro; Konno, Naotake; Takeda, Takumi; Fujita, Kohei; Konishi, Teruko; Nishihara, Masahiro; Uchimiya, Hirofumi

    2014-10-01

    Bud dormancy is an adaptive strategy that perennials use to survive unfavorable conditions. Gentians (Gentiana), popular alpine flowers and ornamentals, produce overwintering buds (OWBs) that can persist through the winter, but the mechanisms regulating dormancy are currently unclear. In this study, we conducted targeted metabolome analysis to obtain clues about the metabolic mechanisms involved in regulating OWB dormancy. Multivariate analysis of metabolite profiles revealed metabolite patterns characteristic of dormant states. The concentrations of gentiobiose [?-D-Glcp-(1?6)-D-Glc] and gentianose [?-D-Glcp-(1?6)-D-Glc-(1?2)-d-Fru] significantly varied depending on the stage of OWB dormancy, and the gentiobiose concentration increased prior to budbreak. Both activation of invertase and inactivation of ?-glucosidase resulted in gentiobiose accumulation in ecodormant OWBs, suggesting that gentiobiose is seldom used as an energy source but is involved in signaling pathways. Furthermore, treatment with exogenous gentiobiose induced budbreak in OWBs cultured in vitro, with increased concentrations of sulfur-containing amino acids, GSH, and ascorbate (AsA), as well as increased expression levels of the corresponding genes. Inhibition of GSH synthesis suppressed gentiobiose-induced budbreak accompanied by decreases in GSH and AsA concentrations and redox status. These results indicate that gentiobiose, a rare disaccharide, acts as a signal for dormancy release of gentian OWBs through the AsA-GSH cycle. PMID:25326293

  1. Transcriptomic Analysis of the Underground Renewal Buds during Dormancy Transition and Release in ‘Hangbaishao’ Peony (Paeonia lactiflora)

    PubMed Central

    Zhang, Jiaping; Wang, Guanqun; Li, Xin; Xia, Yiping

    2015-01-01

    Paeonia lactiflora is one of the most famous species of herbaceous peonies with gorgeous flowers. Bud dormancy is a crucial developmental process that allows P. lactiflora to survive unfavorable environmental conditions. However, little information is available on the molecular mechanism of the bud dormancy in P. lactiflora. We performed de novo transcriptome sequencing using the Illumina RNA sequencing platform for the underground renewal buds of P. lactiflora ‘Hangbaishao’ to study the molecular mechanism underlying its bud dormancy transition (the period from endodormancy to ecodormancy) and release (the period from ecodormancy to bud elongation and sprouting). Approximately 300 million high-quality clean reads were generated and assembled into 207,827 (mean length = 828 bp) and 51,481 (mean length = 1250 bp) unigenes using two assembly methods named “Trinity” and “Trinity+PRICE”, respectively. Based on the data obtained by the latter method, 32,316 unigenes were annotated by BLAST against various databases. Approximately 1,251 putative transcription factors were obtained, of which the largest number of unique transcripts belonged to the basic helix-loop-helix protein (bHLH) transcription factor family, and five of the top ten highly expressed transcripts were annotated as dehydrin (DHN). A total of 17,705 simple sequence repeat (SSR) motifs distributed in 13,797 sequences were obtained. The budbreak morphology, levels of indole-3-acetic acid (IAA) and abscisic acid (ABA), and activities of guaiacol peroxidase (POD) and catalase (CAT) were observed. The expression of 20 interested unigenes, which annotated as DHN, heat shock protein (HSP), histone, late elongated hypocotyl (LHY), and phytochrome (PHY), and so on, were also analyzed. These studies were based on morphological, physiological, biochemical, and molecular levels and provide comprehensive insight into the mechanism of dormancy transition and release in P. lactiflora. Transcriptome dataset can be highly valuable for future investigation on gene expression networks in P. lactiflora as well as research on dormancy in other non-model perennial horticultural crops of commercial significance. PMID:25790307

  2. Conservation and divergence of four kiwifruit SVP-like MADS-box genes suggest distinct roles in kiwifruit bud dormancy and flowering

    PubMed Central

    Wu, Rong-Mei; Walton, Eric F.; Richardson, Annette C.; Wood, Marion; Hellens, Roger P.; Varkonyi-Gasic, Erika

    2012-01-01

    MADS-box genes similar to Arabidopsis SHORT VEGETATIVE PHASE (SVP) have been implicated in the regulation of flowering in annual species and bud dormancy in perennial species. Kiwifruit (Actinidia spp.) are woody perennial vines where bud dormancy and out-growth affect flower development. To determine the role of SVP-like genes in dormancy and flowering of kiwifruit, four MADS-box genes with homology to Arabidopsis SVP, designated SVP1, SVP2, SVP3, and SVP4, have been identified and analysed in kiwifruit and functionally characterized in Arabidopsis. Phylogenetic analysis indicate that these genes fall into different sub-clades within the SVP-like gene group, suggesting distinct functions. Expression was generally confined to vegetative tissues, and increased transcript accumulation in shoot buds over the winter period suggests a role for these genes in bud dormancy. Down-regulation before flower differentiation indicate possible roles as floral repressors. Over-expression and complementation studies in Arabidopsis resulted in a range of floral reversion phenotypes arising from interactions with Arabidopsis MADS-box proteins, but only SVP1 and SVP3 were able to complement the svp mutant. These results suggest that the kiwifruit SVP-like genes may have distinct roles during bud dormancy and flowering. PMID:22071267

  3. Extensive transcriptome changes during natural onset and release of vegetative bud dormancy in Populus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    To survive winter conditions, axillary buds of poplar transition from paradormancy to endodormancy. Following sufficient chilling, endodormant axillary buds will transition from endodormancy to ecodormancy. We utilized the near whole genome NimbleGen poplar microarrays to follow transcriptome diff...

  4. ptr-MIR169 is a posttranscriptional repressor of PtrHAP2 during vegetative bud dormancy period of aspen (Populus tremuloides) trees

    SciTech Connect

    Potkar, Rewati; Recla, Jill; Busov, Victor

    2013-02-15

    Highlights: ► We show a novel microRNA-mediated mechanism for control of bud dormancy in trees. ► ptr-MIR169a and PtrHAP2–5 gene showed inverse expression during dormancy period. ► The PtrHAP2–5 decline in abundance correlated with high ptr-MIR169a levels. ► PtrHAP2–5 cleavage occurred at the miR169 site during PtrHAP2–5 transcript decline. ► Our results show that miR169 attenuates PtrHAP2–5 transcript during dormancy. -- Abstract: Dormancy is a mechanism evolved in woody perennial plants to survive the winter freezing and dehydration stress via temporary suspension of growth. We have identified two aspen microRNAs (ptr-MIR169a and ptr-MIR169h) which were highly and specifically expressed in dormant floral and vegetative buds. ptr-MIR169a and its target gene PtrHAP2–5 showed inverse expression patterns during the dormancy period. ptr-MIR169a transcript steadily increased through the first half of the dormancy period and gradually declined with the approach of active growing season. PtrHAP2–5 abundance was higher in the beginning of the dormancy period but rapidly declined thereafter. The decline of PtrHAP2–5 correlated with the high levels of ptr-MIR169a accumulation, suggesting miR169-mediated attenuation of the target PtrHAP2–5 transcript. We experimentally verified the cleavage of PtrHAP2–5 at the predicted miR169a site at the time when PtrHAP2–5 transcript decline was observed. HAP2 is a subunit of a nuclear transcription factor Y (NF-Y) complex consisting of two other units, HAP3 and HAP5. Using digital expression profiling we show that poplar HAP2 and HAP5 are preferentially detected in dormant tissues. Our study shows that microRNAs play a significant and as of yet unknown and unstudied role in regulating the timing of bud dormancy in trees.

  5. DNA methylation/demethylation programming during peach flower bud dormancy release, development and blooming

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Peach flower bud development undergoes a long, complex and temperature-dependent regulation process with cessation of growth in response to cool temperatures in late fall, a slow but gradual development during the chilling period in winter, and eventually blooming in early spring. It has been demon...

  6. SUGARS, HORMONES, AND ENVIRONMENT AFFECT THE DORMANCY STATUS IN UNDERGROUND ADVENTITIOUS BUDS OF LEAFY SPURGE (EUPHORBIA ESULA)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Leafy spurge is a deep-rooted perennial weed that propagates vegetatively from an abundance of underground adventitious buds located on roots and crown (root and crown buds). Signals from both leaves and apical or axillary meristems are known to inhibit root bud growth. To increase our understanding...

  7. A rapid transcriptional activation is induced by the dormancy-breaking chemical hydrogen cyanamide in kiwifruit (Actinidia deliciosa) buds

    PubMed Central

    Walton, Eric F.; Wu, Rong-Mei; Richardson, Annette C.; Davy, Marcus; Hellens, Roger P.; Thodey, Kate; Janssen, Bart J.; Gleave, Andrew P.; Rae, Georgina M.; Wood, Marion; Schaffer, Robert J.

    2009-01-01

    Budbreak in kiwifruit (Actinidia deliciosa) can be poor in locations that have warm winters with insufficient winter chilling. Kiwifruit vines are often treated with the dormancy-breaking chemical hydrogen cyanamide (HC) to increase and synchronize budbreak. This treatment also offers a tool to understand the processes involved in budbreak. A genomics approach is presented here to increase our understanding of budbreak in kiwifruit. Most genes identified following HC application appear to be associated with responses to stress, but a number of genes appear to be associated with the reactivation of growth. Three patterns of gene expression were identified: Profile 1, an HC-induced transient activation; Profile 2, an HC-induced transient activation followed by a growth-related activation; and Profile 3, HC- and growth-repressed. One group of genes that was rapidly up-regulated in response to HC was the glutathione S-transferase (GST) class of genes, which have been associated with stress and signalling. Previous budbreak studies, in three other species, also report up-regulated GST expression. Phylogenetic analysis of these GSTs showed that they clustered into two sub-clades, suggesting a strong correlation between their expression and budbreak across species. PMID:19651683

  8. Short day transcriptomic programming during induction of dormancy in grapevine.

    PubMed

    Fennell, Anne Y; Schlauch, Karen A; Gouthu, Satyanarayana; Deluc, Laurent G; Khadka, Vedbar; Sreekantan, Lekha; Grimplet, Jerome; Cramer, Grant R; Mathiason, Katherine L

    2015-01-01

    Bud dormancy in grapevine is an adaptive strategy for the survival of drought, high and low temperatures and freeze dehydration stress that limit the range of cultivar adaptation. Therefore, development of a comprehensive understanding of the biological mechanisms involved in bud dormancy is needed to promote advances in selection and breeding, and to develop improved cultural practices for existing grape cultivars. The seasonally indeterminate grapevine, which continuously develops compound axillary buds during the growing season, provides an excellent system for dissecting dormancy, because the grapevine does not transition through terminal bud development prior to dormancy. This study used gene expression patterns and targeted metabolite analysis of two grapevine genotypes that are short photoperiod responsive (Vitis riparia) and non-responsive (V. hybrid, Seyval) for dormancy development to determine differences between bud maturation and dormancy commitment. Grapevine gene expression and metabolites were monitored at seven time points under long (LD, 15 h) and short (SD, 13 h) day treatments. The use of age-matched buds and a small (2 h) photoperiod difference minimized developmental differences and allowed us to separate general photoperiod from dormancy specific gene responses. Gene expression profiles indicated three distinct phases (perception, induction and dormancy) in SD-induced dormancy development in V. riparia. Different genes from the NAC DOMAIN CONTAINING PROTEIN 19 and WRKY families of transcription factors were differentially expressed in each phase of dormancy. Metabolite and transcriptome analyses indicated ABA, trehalose, raffinose and resveratrol compounds have a potential role in dormancy commitment. Finally, a comparison between V. riparia compound axillary bud dormancy and dormancy responses in other species emphasized the relationship between dormancy and the expression of RESVERATROL SYNTHASE and genes associated with C3HC4-TYPE RING FINGER and NAC DOMAIN CONTAINING PROTEIN 19 transcription factors. PMID:26582400

  9. Short day transcriptomic programming during induction of dormancy in grapevine

    PubMed Central

    Fennell, Anne Y.; Schlauch, Karen A.; Gouthu, Satyanarayana; Deluc, Laurent G.; Khadka, Vedbar; Sreekantan, Lekha; Grimplet, Jerome; Cramer, Grant R.; Mathiason, Katherine L.

    2015-01-01

    Bud dormancy in grapevine is an adaptive strategy for the survival of drought, high and low temperatures and freeze dehydration stress that limit the range of cultivar adaptation. Therefore, development of a comprehensive understanding of the biological mechanisms involved in bud dormancy is needed to promote advances in selection and breeding, and to develop improved cultural practices for existing grape cultivars. The seasonally indeterminate grapevine, which continuously develops compound axillary buds during the growing season, provides an excellent system for dissecting dormancy, because the grapevine does not transition through terminal bud development prior to dormancy. This study used gene expression patterns and targeted metabolite analysis of two grapevine genotypes that are short photoperiod responsive (Vitis riparia) and non-responsive (V. hybrid, Seyval) for dormancy development to determine differences between bud maturation and dormancy commitment. Grapevine gene expression and metabolites were monitored at seven time points under long (LD, 15 h) and short (SD, 13 h) day treatments. The use of age-matched buds and a small (2 h) photoperiod difference minimized developmental differences and allowed us to separate general photoperiod from dormancy specific gene responses. Gene expression profiles indicated three distinct phases (perception, induction and dormancy) in SD-induced dormancy development in V. riparia. Different genes from the NAC DOMAIN CONTAINING PROTEIN 19 and WRKY families of transcription factors were differentially expressed in each phase of dormancy. Metabolite and transcriptome analyses indicated ABA, trehalose, raffinose and resveratrol compounds have a potential role in dormancy commitment. Finally, a comparison between V. riparia compound axillary bud dormancy and dormancy responses in other species emphasized the relationship between dormancy and the expression of RESVERATROL SYNTHASE and genes associated with C3HC4-TYPE RING FINGER and NAC DOMAIN CONTAINING PROTEIN 19 transcription factors. PMID:26582400

  10. DORMANCY ASSOCIATED MADS-BOX genes: a review

    Technology Transfer Automated Retrieval System (TEKTRAN)

    DAM genes encode transcription factors suspected of regulating bud dormancy in numerous perennials. This chapter discusses the functional genetics and regulation of these genes and summarizes the evidence that these transcription factors play a central role in seasonal bud dormancy induction and mai...

  11. Chilling of Dormant Buds Hyperinduces FLOWERING LOCUS T and Recruits GA-Inducible 1,3-β-Glucanases to Reopen Signal Conduits and Release Dormancy in Populus[W][OA

    PubMed Central

    Rinne, Päivi L.H.; Welling, Annikki; Vahala, Jorma; Ripel, Linda; Ruonala, Raili; Kangasjärvi, Jaakko; van der Schoot, Christiaan

    2011-01-01

    In trees, production of intercellular signals and accessibility of signal conduits jointly govern dormancy cycling at the shoot apex. We identified 10 putative cell wall 1,3-β-glucanase genes (glucan hydrolase family 17 [GH17]) in Populus that could turn over 1,3-β-glucan (callose) at pores and plasmodesmata (PD) and investigated their regulation in relation to FT and CENL1 expression. The 10 genes encode orthologs of Arabidopsis thaliana BG_ppap, a PD-associated glycosylphosphatidylinositol (GPI) lipid-anchored protein, the Arabidopsis PD callose binding protein PDCB, and a birch (Betula pendula) putative lipid body (LB) protein. We found that these genes were differentially regulated by photoperiod, by chilling (5°C), and by feeding of gibberellins GA3 and GA4. GA3 feeding upregulated all LB-associated GH17s, whereas GA4 upregulated most GH17s with a GPI anchor and/or callose binding motif, but only GA4 induced true bud burst. Chilling upregulated a number of GA biosynthesis and signaling genes as well as FT, but not CENL1, while the reverse was true for both GA3 and GA4. Collectively, the results suggest a model for dormancy release in which chilling induces FT and both GPI lipid-anchored and GA3-inducible GH17s to reopen signaling conduits in the embryonic shoot. When temperatures rise, the reopened conduits enable movement of FT and CENL1 to their targets, where they drive bud burst, shoot elongation, and morphogenesis. PMID:21282527

  12. Physiological differences between bud breaking and flowering after dormancy completion revealed by DAM and FT/TFL1 expression in Japanese pear (Pyrus pyrifolia).

    PubMed

    Ito, Akiko; Saito, Takanori; Sakamoto, Daisuke; Sugiura, Toshihiko; Bai, Songling; Moriguchi, Takaya

    2016-01-01

    The regulatory mechanisms underlying bud breaking (scale leaf elongation) and flowering in the lateral flower buds of Japanese pear (Pyrus pyrifolia Nakai 'Kosui') are unknown. To more fully characterize these processes, we treated pear trees with different amounts of chilling initiated at different times. Chilling for ∼900 h at 6 °C always induced bud breaking (scale elongation in ≥70% lateral flower bud) when provided between October and February, whereas chilling provided earlier (between October and December) was less effective on flowering (floret growth and development) than later chilling and the flowering rate increased with longer chilling durations. During chilling, the expression of pear DAMs (PpMADS13-1, 13-2 and 13-3) in lateral flower buds decreased as chilling accumulated irrespective of the timing of chilling. In addition, pear TFL1 (PpTFL1-1a) in the lateral flower buds was expressed at higher levels when the time interval for chilling was earlier. On the other hand, during forcing at 15 °C after chilling, the expression pattern of all three PpMADS13 genes was similar among the treatments, and the expression levels seemed lower in the treatment where scale leaves of the lateral flower bud elongated faster, whereas pear FT (PpFT2a) was expressed at higher levels in the buds whose flower clusters elongated more vigorously during forcing. From these results, we infer that flowering time may be mediated via the balance of flowering-related genes FT and TFL1, whereas bud breaking may be regulated via the DAM genes in Japanese pear. PMID:26546364

  13. Stamen development and winter dormancy in apricot (Prunus armeniaca)

    PubMed Central

    Julian, C.; Rodrigo, J.; Herrero, M.

    2011-01-01

    Background and Aims In temperate woody perennials, flower bud development is halted during the winter, when the buds enter dormancy. This dormant period is a prerequisite for adequate flowering, is genetically regulated, and plays a clear role in possibly adapting species and cultivars to climatic areas. However, information on the biological events underpinning dormancy is lacking. Stamen development, with clear differentiated stages, appears as a good framework to put dormancy in a developmental context. Here, stamen developmental changes are characterized in apricot (Prunus armeniaca) and are related to dormancy. Methods Stamen development was characterized cytochemically from the end of August to March, over 4 years. Developmental changes were related to dormancy, using the existing empirical information on chilling requirements. Key Results Stamen development continued during the autumn, and the flower buds entered dormancy with a fully developed sporogenous tissue. Although no anatomical changes were observed during dormancy, breaking of dormancy occurred following a clear sequence of events. Starch accumulated in particular places, pre-empting further development in those areas. Vascular bundles developed and pollen mother cells underwent meiosis followed by microspore development. Conclusions Dormancy appears to mark a boundary between the development of the sporogenous tissue and the occurrence of meiosis for further microspore development. Breaking of dormancy occurs following a clear sequence of events, providing a developmental context in which to study winter dormancy and to evaluate differences in chilling requirements among genotypes. PMID:21474504

  14. Transcriptome analysis identifies novel responses and potential regulatory genes involved in seasonal dormancy transitions of leafy spurge (Euphorbia esula L.)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Dormancy transitions in crown buds of leafy spurge were investigated using 23K element cDNA microarrays. These data represent the first large-scale transcriptome analysis of dormancy in underground buds of an herbaceous perennial species. Crown buds collected monthly from August through December, ov...

  15. Detection of seed dormancy QTL in three F2 families of peach (Prunus persica)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Dormancy is a condition that delays or inhibits growth in seed, vegetative buds, and floral buds. In peach, seed germination occurs when seed accumulate sufficient stratification and growing degree hours to break dormancy and begin growing. Correlations have been reported between mean seed stratifi...

  16. Dormancy release and flowering time in Ziziphus jujuba Mill., a "direct flowering" fruit tree, has a facultative requirement for chilling.

    PubMed

    Meir, Michal; Ransbotyn, Vanessa; Raveh, Eran; Barak, Simon; Tel-Zur, Noemi; Zaccai, Michele

    2016-03-15

    In deciduous fruit trees, the effect of chilling on flowering has mostly been investigated in the "indirect flowering" group, characterized by a period of rest between flower bud formation and blooming. In the present study, we explored the effects of chilling and chilling deprivation on the flowering of Ziziphus jujuba, a temperate deciduous fruit tree belonging to the "direct flowering" group, in which flower bud differentiation, blooming and fruit development occur after dormancy release, during a single growing season. Dormancy release, vegetative growth and flowering time in Z. jujuba cv. Ben-Li were assessed following several treatments of chilling. Chilling treatments quantitatively decreased the timing of vegetative bud dormancy release, thereby accelerating flowering, but had no effect on the time from dormancy release to flowering. Trees grown at a constant temperature of 25°C, without chilling, broke dormancy and flowered, indicating the facultative character of chilling in this species. We measured the expression of Z. jujuba LFY and AP1 homologues (ZjLFY and ZjAP1). Chilling decreased ZjLFY expression in dormant vegetative buds but had no effect on ZjAP1expression, which reached peak expression before dormancy release and at anthesis. In conclusion, chilling is not obligatory for dormancy release of Z. jujuba cv. Ben-Li vegetative buds. However, the exposure to chilling during dormancy does accelerate vegetative bud dormancy release and flowering. PMID:26949231

  17. Genomics approach to investigate seasonal dormancy transitions in leafy spurge (Euphorbia esula)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Leafy spurge is a noxious perennial weed that infests range lands in the Northern Great Plains. It is being used as a model to investigate dormancy in underground adventitious buds, i.e., root and crown buds. The leafy spurge EST-database contains 45,314 high-quality sequences which assembled into 2...

  18. The resemblance and disparity of gene expression in dormant and non-dormant seeds and crown buds of leafy spurge (Euphorbia esula)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Overlaps in transcriptome profiles between different phases of bud and seed dormancy have not been determined. Thus, we compared various phases of dormancy between seeds and buds to identify common genes and molecular processes. Cluster analysis of expression profiles for 201 selected genes indicate...

  19. Cryotolerance of apple tree bud is independent of endodormancy

    PubMed Central

    Bilavcik, Alois; Zamecnik, Jiri; Faltus, Milos

    2015-01-01

    Increasing interest in cryopreservation of dormant buds reveals the need for better understanding of the role of dormancy in cryotolerance. Dormancy stage and low-temperature survival of vegetative apple buds (Malus domestica Borkh.), cultivars ‘Sampion’ and ‘Spartan’, collected from orchard were evaluated during three seasons contrasting in temperature and precipitation throughout the arrested plant growth period. During each season, the cultivars differed either in the onset of the endodormancy or in the length of the endodormant period. A simple relation between endodormancy of the buds and their water content was not detected. The cryosurvival of vegetative apple buds of both cultivars correlated with their cold hardening without direct regard to their particular phase of dormancy. The period of the highest bud cryotolerance after low-temperature exposure overlapped with the endodormant period in some evaluated seasons. Both cultivars had the highest cryosurvival in December and January. The presented data were compared with our previous results from a dormancy study of in vitro apple culture. Endodormancy coincided with the period of successful cryosurvival of apple buds after liquid nitrogen exposure, but as such, it was not decisive for their survival and did not limit their successful cryopreservation. PMID:26442012

  20. Effect of GA(4 + 7) on the initiation and development of the inflorescence bud of evergreen azalea.

    PubMed

    Bodson, M

    1986-06-01

    Apical buds of evergreen azalea (Rhododendron sp.) were treated with GA(4 + 7) at different stages of development. Treatment of vegetative buds stimulated shoot growth, slightly delayed both flower initiation and development, but increased the number of flower primordia. Treatment at the time of floral transition induced bud abortion at an early stage of the reproductive development. Treatment of inflorescence buds which contained at least one complete flower substituted for chilling in overcoming dormancy and prevented inflorescence bud abortion. PMID:14975912

  1. Dehydration and vernalization treatments identify overlapping molecular networks impacting endodormancy maintenance in leafy spurge crown buds

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Leafy spurge (Euphorbia esula L.) is an herbaceous perennial weed that reproduces vegetatively from an abundance of underground adventitious buds (UABs), which undergo well-defined phases of seasonal dormancy (para-, endo- and eco-dormancy). In this study, the effects of dehydration-stress on vegeta...

  2. Cold Treatment Breaks Dormancy but Jeopardizes Flower Quality in Camellia japonica L.

    PubMed

    Berruti, Andrea; Christiaens, Annelies; Keyser, Ellen De; Labeke, Marie-Christine Van; Scariot, Valentina

    2015-01-01

    Camellia japonica L. is an evergreen shrub whose cultivars are of great ornamental value. In autumn, after flower bud differentiation, dormancy is initiated. As in many other spring flowering woody ornamentals, winter low temperatures promote dormancy release of both flower and vegetative buds. However, warm spells during late autumn and winter can lead to unfulfilled chilling requirements leading to erratic and delayed flowering. We hypothesized that storing plants at no light and low temperature could favor dormancy breaking and lead to early and synchronized flowering in response to forcing conditions in C. japonica 'Nuccio's Pearl'. Plants with fully developed floral primordia were stored at dark, 7°C, and RH > 90% for up to 8 weeks. To monitor endodormancy release during the storage, we evaluated the content of abscisic acid (ABA) in flower buds and the expression profiles of five putative genes related to dormancy and cold acclimation metabolism in leaves and flower buds. In addition, the expression of four anthocyanin biosynthesis pathway genes was profiled in flower buds to assess the effect of the treatment on flower pigment biosynthesis. At 0, 4, 6, and 8 weeks of cold treatment, 10 plants were transferred to the greenhouse and forced to flower. Forced plant flower qualities and growth were observed. The ABA content and the expression profiles of two dormancy-related genes (CjARP and CjDEH) suggested that dormancy breaking occurred after 6-8 weeks of cold treatment. Overall, plants treated for 6-8 weeks showed earlier vegetative sprouting, enhanced, and homogeneous flowering with reduced forcing time. Prolonged cold treatments also reduced flower size and longevity, anthocyanin content, and pigment biosynthesis-related gene transcripts. In conclusion, the cold treatment had a promotive effect on dormancy breaking but caused severe drawbacks on flower quality. PMID:26617623

  3. Cold Treatment Breaks Dormancy but Jeopardizes Flower Quality in Camellia japonica L.

    PubMed Central

    Berruti, Andrea; Christiaens, Annelies; Keyser, Ellen De; Labeke, Marie-Christine Van; Scariot, Valentina

    2015-01-01

    Camellia japonica L. is an evergreen shrub whose cultivars are of great ornamental value. In autumn, after flower bud differentiation, dormancy is initiated. As in many other spring flowering woody ornamentals, winter low temperatures promote dormancy release of both flower and vegetative buds. However, warm spells during late autumn and winter can lead to unfulfilled chilling requirements leading to erratic and delayed flowering. We hypothesized that storing plants at no light and low temperature could favor dormancy breaking and lead to early and synchronized flowering in response to forcing conditions in C. japonica ‘Nuccio’s Pearl’. Plants with fully developed floral primordia were stored at dark, 7°C, and RH > 90% for up to 8 weeks. To monitor endodormancy release during the storage, we evaluated the content of abscisic acid (ABA) in flower buds and the expression profiles of five putative genes related to dormancy and cold acclimation metabolism in leaves and flower buds. In addition, the expression of four anthocyanin biosynthesis pathway genes was profiled in flower buds to assess the effect of the treatment on flower pigment biosynthesis. At 0, 4, 6, and 8 weeks of cold treatment, 10 plants were transferred to the greenhouse and forced to flower. Forced plant flower qualities and growth were observed. The ABA content and the expression profiles of two dormancy-related genes (CjARP and CjDEH) suggested that dormancy breaking occurred after 6–8 weeks of cold treatment. Overall, plants treated for 6–8 weeks showed earlier vegetative sprouting, enhanced, and homogeneous flowering with reduced forcing time. Prolonged cold treatments also reduced flower size and longevity, anthocyanin content, and pigment biosynthesis-related gene transcripts. In conclusion, the cold treatment had a promotive effect on dormancy breaking but caused severe drawbacks on flower quality. PMID:26617623

  4. Transcriptome analysis identifies novel responses and potential regulatory genes involved in seasonal dormancy transitions of leafy spurge (Euphorbia esula L.)

    PubMed Central

    Horvath, David P; Chao, Wun S; Suttle, Jeffrey C; Thimmapuram, Jyothi; Anderson, James V

    2008-01-01

    Background Dormancy of buds is a critical developmental process that allows perennial plants to survive extreme seasonal variations in climate. Dormancy transitions in underground crown buds of the model herbaceous perennial weed leafy spurge were investigated using a 23 K element cDNA microarray. These data represent the first large-scale transcriptome analysis of dormancy in underground buds of an herbaceous perennial species. Crown buds collected monthly from August through December, over a five year period, were used to monitor the changes in the transcriptome during dormancy transitions. Results Nearly 1,000 genes were differentially-expressed through seasonal dormancy transitions. Expected patterns of gene expression were observed for previously characterized genes and physiological processes indicated that resolution in our analysis was sufficient for identifying shifts in global gene expression. Conclusion Gene ontology of differentially-expressed genes suggests dormancy transitions require specific alterations in transport functions (including induction of a series of mitochondrial substrate carriers, and sugar transporters), ethylene, jasmonic acid, auxin, gibberellic acid, and abscisic acid responses, and responses to stress (primarily oxidative and cold/drought). Comparison to other dormancy microarray studies indicated that nearly half of the genes identified in our study were also differentially expressed in at least two other plant species during dormancy transitions. This comparison allowed us to identify a particular MADS-box transcription factor related to the DORMANCY ASSOCIATED MADS-BOX genes from peach and hypothesize that it may play a direct role in dormancy induction and maintenance through regulation of FLOWERING LOCUS T. PMID:19014493

  5. Seed dormancy in alpine species

    PubMed Central

    Schwienbacher, Erich; Navarro-Cano, Jose Antonio; Neuner, Gilbert; Erschbamer, Brigitta

    2011-01-01

    In alpine species the classification of the various mechanisms underlying seed dormancy has been rather questionable and controversial. Thus, we investigated 28 alpine species to evaluate the prevailing types of dormancy. Embryo type and water impermeability of seed coats gave an indication of the potential seed dormancy class. To ascertain the actual dormancy class and level, we performed germination experiments comparing the behavior of seeds without storage, after cold-dry storage, after cold-wet storage, and scarification. We also tested the light requirement for germination in some species. Germination behavior was characterized using the final germination percentage and the mean germination time. Considering the effects of the pretreatments, a refined classification of the prevailing dormancy types was constructed based on the results of our pretreatments. Only two out of the 28 species that we evaluated had predominantly non-dormant seeds. Physiological dormancy was prevalent in 20 species, with deep physiological dormancy being the most abundant, followed by non-deep and intermediate physiological dormancy. Seeds of four species with underdeveloped embryos were assigned to the morphophysiologial dormancy class. An impermeable seed coat was identified in two species, with no additional physiological germination block. We defined these species as having physical dormancy. Light promoted the germination of seeds without storage in all but one species with physiological dormancy. In species with physical dormancy, light responses were of minor importance. We discuss our new classification in the context of former germination studies and draw implications for the timing of germination in the field. PMID:24415831

  6. Dormant buds

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Dormant vegetative buds from diverse species can be preserved using cryopreservation. Sakai (1960) provided one of the first studies showing that winter twigs of poplar (Populus sieboldi) and willow (Salix koriyanagi) could survive low temperatures if slowly cooled prior to immersion in liquid nitr...

  7. Functional diversification of the dehydrin gene family in apple and its contribution to cold acclimation during dormancy.

    PubMed

    Falavigna, Vítor da Silveira; Miotto, Yohanna Evelyn; Porto, Diogo Denardi; Anzanello, Rafael; Santos, Henrique Pessoa dos; Fialho, Flávio Bello; Margis-Pinheiro, Márcia; Pasquali, Giancarlo; Revers, Luís Fernando

    2015-11-01

    Dehydrins (DHN) are proteins involved in plant adaptive responses to abiotic stresses, mainly dehydration. Several studies in perennial crops have linked bud dormancy progression, a process characterized by the inability to initiate growth from meristems under favorable conditions, with DHN gene expression. However, an in-depth characterization of DHNs during bud dormancy progression is still missing. An extensive in silico characterization of the apple DHN gene family was performed. Additionally, we used five different experiments that generated samples with different dormancy status, including genotypes with contrasting dormancy traits, to analyze how DHN genes are being regulated during bud dormancy progression in apple by real-time quantitative polymerase chain reaction (RT-qPCR). Duplication events took place in the diversification of apple DHN family. Additionally, MdDHN genes presented tissue- and bud dormant-specific expression patterns. Our results indicate that MdDHN genes are highly divergent in function, with overlapping levels, and that their expressions are fine-tuned by the environment during the dormancy process in apple. PMID:25809953

  8. SEED DORMANCY, GENETICS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Technical Seed dormancy is defined as the temporary failure of a viable seed to germinate, after a specific length of time, in a particular set of environmental conditions that later evoke germination when the restrictive state has been terminated by either natural or artifical conditions. Seed dor...

  9. SEED DORMANCY, AGRICULTURAL IMPORTANCE

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Technical Seed dormancy has been defined as the temporary failure of a viable seed to germinate, after a specific length of time, in a particular set of environmental conditions that later evoke germination when the restrictive state has been terminated by either natural or artificial conditions. S...

  10. Transcriptome Profiles Associated with Dormancy Status in Seeds of Leafy Spurge (Euphorbia esula)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Leafy spurge is an herbaceous perennial weed that reproduces vegetatively through buds and sexually through seeds. Since knowledge about seed dormancy/germination of this species is limited, objectives of this study were to examine effects of constant (21 d at 20°C), alternating (21 d at 20:30°C,16:...

  11. Identifying genetic networks associated with dormancy transitions in the perennial weed leafy spurge (Euphorbia esula)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Leafy spurge is an invasive perennial weed currently being used as a model to investigate weedy traits. Dormancy-imposed inhibition of vegetative reproduction from underground adventitious buds, located on the crown and lateral roots, is one of the key characteristics leading to the persistence of t...

  12. Cold storage to overcome dormancy affects the carbon balance of azalea.

    PubMed

    Christiaens, A; De Keyser, E; Lootens, P; Pauwels, E; Roldan-Ruiz, I; De Riek, J; Gobin, B; Van Labeke, M-C

    2014-01-01

    Flower bud dormancy in azalea (Rhododendron simsii) is broken by artificial cold treatment and this will have its consequences on carbon reserves and photosynthesis. The effect of cold storage at 7 °C on carbohydrate and starch content in leaves and flower buds of an early ('Nordlicht') and semi-early ('M. Marie) flowering cultivar was quantified. Carbon loss due to respiration was lowest for 'M. Marie'. Photosynthetic measurements on 'Nordlicht' showed that photosynthesis 3 days after cold treatment (plants ready to flower) was improved compared to before cold treatment (plants with dormant flower buds). PMID:25864312

  13. Criticality and Cancer Dormancy

    NASA Astrophysics Data System (ADS)

    Wu, Amy; Liao, David; Kirlin, Vladimir; Tamita, Corina; Levin, Simon; Sturm, James; Austin, Robert

    The presence of driver mutations and subsequent clonal expansion by Darwinian evolution does not explain dormancy and re-emergence of cancer from a community of cancer and stromal cells. Dormancy appears to be a collective property of multiple cell communities including non-cancerous cells. At the simplest level, we view cancer cells interacting with stromal cells via complex, non-linear population dynamics, dynamics which can lead to very non-intuitive but perhaps deterministic and understandable progression dynamics of cancer. We explore here the dynamics of stromal-cancer cell populations in the presence of a chemotherapy drug gradient to determine to what extent the time-dependence of the populations can be quantitively understood in spite of the underlying complexity of the individual agents. The surprising result is that a basic understanding, in a quantitive and predictive manner, can be achieved. It will be intriguing to move to predictive drug dosages, the population dynamics presented here provide a model system for the clinic.

  14. Early wound reactions of Japanese maple during winter dormancy: the effect of two contrasting temperature regimes

    PubMed Central

    Copini, Paul; den Ouden, Jan; Decuyper, Mathieu; Mohren, Godefridus M. J.; Loomans, Antoon J. M.; Sass-Klaassen, Ute

    2014-01-01

    During winter dormancy, temperate trees are capable of only a restricted response to wounding. Depending on the ambient temperature during winter dormancy, wounded trees may start compartmentalization, e.g. by producing inhibitory compounds, but it is thought that processes involving cell proliferation, such as the formation of callus and wound xylem, are delayed until the next growing season. We investigated the effect of two contrasting temperature regimes on early reactions of Acer palmatum trees to wounding during winter bud dormancy. Stems of A. palmatum trees were wounded and stored under an ambient temperature of 4 or 15 °C for 3 weeks during winter bud dormancy. We then studied wound reactions in the living bark, cambial region and xylem. In the 4 °C treatment, wound reactions were virtually absent. In the 15 °C treatment, however, trees reacted to wounding by dieback of the cortex and phloem and by the formation of ligno-suberized layers. In the cambial zone, cambial dieback occurred and callus tissue and wound xylem were formed locally, close to the wound margins. In the xylem, compartmentalization took place by deposition of inhibitory compounds in fibre cells and vessel elements. We conclude that temperature is an important factor in wound reactions during winter dormancy, and may even induce proliferation of callus and wound xylem within a 3-week period. It therefore seems likely that trees that have been wounded during dormancy in areas with mild or warm winters might cope better with wounding, as unlike trees in cold environments, they may compartmentalize wounds even during winter dormancy. PMID:25275087

  15. Chilling-Mediated DNA Methylation Changes during Dormancy and Its Release Reveal the Importance of Epigenetic Regulation during Winter Dormancy in Apple (Malus x domestica Borkh.).

    PubMed

    Kumar, Gulshan; Rattan, Usha Kumari; Singh, Anil Kumar

    2016-01-01

    Winter dormancy is a well known mechanism adopted by temperate plants, to mitigate the chilling temperature of winters. However, acquisition of sufficient chilling during winter dormancy ensures the normal phenological traits in subsequent growing period. Thus, low temperature appears to play crucial roles in growth and development of temperate plants. Apple, being an important temperate fruit crop, also requires sufficient chilling to release winter dormancy and normal phenological traits, which are often associated with yield and quality of fruits. DNA cytosine methylation is one of the important epigenetic modifications which remarkably affect the gene expression during various developmental and adaptive processes. In present study, methylation sensitive amplified polymorphism was employed to assess the changes in cytosine methylation during dormancy, active growth and fruit set in apple, under differential chilling conditions. Under high chill conditions, total methylation was decreased from 27.2% in dormant bud to 21.0% in fruit set stage, while no significant reduction was found under low chill conditions. Moreover, the demethylation was found to be decreased, while methylation increased from dormant bud to fruit set stage under low chill as compared to high chill conditions. In addition, RNA-Seq analysis showed high expression of DNA methyltransferases and histone methyltransferases during dormancy and fruit set, and low expression of DNA glcosylases during active growth under low chill conditions, which was in accordance with changes in methylation patterns. The RNA-Seq data of 47 genes associated with MSAP fragments involved in cellular metabolism, stress response, antioxidant system and transcriptional regulation showed correlation between methylation and their expression. Similarly, bisulfite sequencing and qRT-PCR analysis of selected genes also showed correlation between gene body methylation and gene expression. Moreover, significant association between chilling and methylation changes was observed, which suggested that chilling acquisition during dormancy in apple is likely to affect the epigenetic regulation through DNA methylation. PMID:26901339

  16. Chilling-Mediated DNA Methylation Changes during Dormancy and Its Release Reveal the Importance of Epigenetic Regulation during Winter Dormancy in Apple (Malus x domestica Borkh.)

    PubMed Central

    Kumar, Gulshan; Rattan, Usha Kumari; Singh, Anil Kumar

    2016-01-01

    Winter dormancy is a well known mechanism adopted by temperate plants, to mitigate the chilling temperature of winters. However, acquisition of sufficient chilling during winter dormancy ensures the normal phenological traits in subsequent growing period. Thus, low temperature appears to play crucial roles in growth and development of temperate plants. Apple, being an important temperate fruit crop, also requires sufficient chilling to release winter dormancy and normal phenological traits, which are often associated with yield and quality of fruits. DNA cytosine methylation is one of the important epigenetic modifications which remarkably affect the gene expression during various developmental and adaptive processes. In present study, methylation sensitive amplified polymorphism was employed to assess the changes in cytosine methylation during dormancy, active growth and fruit set in apple, under differential chilling conditions. Under high chill conditions, total methylation was decreased from 27.2% in dormant bud to 21.0% in fruit set stage, while no significant reduction was found under low chill conditions. Moreover, the demethylation was found to be decreased, while methylation increased from dormant bud to fruit set stage under low chill as compared to high chill conditions. In addition, RNA-Seq analysis showed high expression of DNA methyltransferases and histone methyltransferases during dormancy and fruit set, and low expression of DNA glcosylases during active growth under low chill conditions, which was in accordance with changes in methylation patterns. The RNA-Seq data of 47 genes associated with MSAP fragments involved in cellular metabolism, stress response, antioxidant system and transcriptional regulation showed correlation between methylation and their expression. Similarly, bisulfite sequencing and qRT-PCR analysis of selected genes also showed correlation between gene body methylation and gene expression. Moreover, significant association between chilling and methylation changes was observed, which suggested that chilling acquisition during dormancy in apple is likely to affect the epigenetic regulation through DNA methylation. PMID:26901339

  17. Effect of alternating day and night temperature on short day-induced bud set and subsequent bud burst in long days in Norway spruce

    PubMed Central

    Olsen, Jorunn E.; Lee, YeonKyeong; Junttila, Olavi

    2014-01-01

    Young seedlings of the conifer Norway spruce exhibit short day (SD)-induced cessation of apical growth and bud set. Although different, constant temperatures under SD are known to modulate timing of bud set and depth of dormancy with development of deeper dormancy under higher compared to lower temperature, systematic studies of effects of alternating day (DT) and night temperatures (NT) are limited. To shed light on this, seedlings of different provenances of Norway spruce were exposed to a wide range of DT-NT combinations during bud development, followed by transfer to forcing conditions of long days (LD) and 18°C, directly or after different periods of chilling. Although no specific effect of alternating DT/NT was found, the results demonstrate that the effects of DT under SD on bud set and subsequent bud break are significantly modified by NT in a complex way. The effects on bud break persisted after chilling. Since time to bud set correlated with the daily mean temperature under SD at DTs of 18 and 21°C, but not a DT of 15°C, time to bud set apparently also depend on the specific DT, implying that the effect of NT depends on the actual DT. Although higher temperature under SD generally results in later bud break after transfer to forcing conditions, the fastest bud flush was observed at intermediate NTs. This might be due to a bud break-hastening chilling effect of intermediate compared to higher temperatures, and delayed bud development to a stage where bud burst can occur, under lower temperatures. Also, time to bud burst in un-chilled seedlings decreased with increasing SD-duration, suggesting that bud development must reach a certain stage before the processes leading to bud burst are initiated. The present results also indicate that low temperature during bud development had a larger effect on the most southern compared to the most northern provenance studied. Decreasing time to bud burst was observed with increasing northern latitude of origin in un-chilled as well as chilled plants. In conclusion, being a highly temperature-dependent process, bud development is strongly delayed by low temperature, and the effects of DT is significantly modified by NT in a complex manner. PMID:25538722

  18. Initiation of Flower Buds in Rhododendron after Application of Growth Retardants.

    PubMed

    Stuart, N W

    1961-07-01

    Vegetative terminals of azalea (Rhododendron spp.) plants of varying ages initiated flower buds promptly after application of the chemical growth retardants, tributyl-2,4-dichlorobenzylphosphonium chloride (phosfon) and (2-chloroethyl) trimethylammonium chloride (CCC), as soil drenches. This response occurred under environmental conditions which prevented or limited flower bud initiation in untreated plants. Normal flowering followed exposure of the treated plants to dormancy-breaking cool storage. PMID:17834301

  19. The Normalcy of Dormancy

    PubMed Central

    Rittershaus, Emily S. C.; Baek, Seung-hun; Sassetti, Christopher M.

    2013-01-01

    All microorganisms are exposed to periodic stresses that inhibit growth. Many bacteria and fungi weather these periods by entering a hardy, non-replicating state, often termed quiescence or dormancy. When this occurs during an infection, the resulting slowly-growing pathogen is able to tolerate both immune insults and prolonged antibiotic exposure. While the stresses encountered in a free-living environment may differ from those imposed by host immunity, these growth-limiting conditions impose common pressures and many of the corresponding microbial responses appear to be universal. In this review, we discuss the common features of these growth-limited states, which suggest new approaches for treating chronic infections such as tuberculosis. PMID:23768489

  20. Alanine aminotransferase controls seed dormancy in barley.

    PubMed

    Sato, Kazuhiro; Yamane, Miki; Yamaji, Nami; Kanamori, Hiroyuki; Tagiri, Akemi; Schwerdt, Julian G; Fincher, Geoffrey B; Matsumoto, Takashi; Takeda, Kazuyoshi; Komatsuda, Takao

    2016-01-01

    Dormancy allows wild barley grains to survive dry summers in the Near East. After domestication, barley was selected for shorter dormancy periods. Here we isolate the major seed dormancy gene qsd1 from wild barley, which encodes an alanine aminotransferase (AlaAT). The seed dormancy gene is expressed specifically in the embryo. The AlaAT isoenzymes encoded by the long and short dormancy alleles differ in a single amino acid residue. The reduced dormancy allele Qsd1 evolved from barleys that were first domesticated in the southern Levant and had the long dormancy qsd1 allele that can be traced back to wild barleys. The reduced dormancy mutation likely contributed to the enhanced performance of barley in industrial applications such as beer and whisky production, which involve controlled germination. In contrast, the long dormancy allele might be used to control pre-harvest sprouting in higher rainfall areas to enhance global adaptation of barley. PMID:27188711

  1. Localization, characterization and candidate gene discovery for genes controlling dormancy, chilling requirement, bloom time, and heat requirement in Prunus species.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Perennial fruiting trees require sustained exposure to low, near freezing, temperatures before vigorous floral and vegetative bud break is possible after the resumption of warm temperatures in the spring. The depth of dormancy, duration of chilling required (the chilling requirement, CR) blooming da...

  2. Transcriptomic changes during tuber dormancy release process revealed by RNA sequencing in potato.

    PubMed

    Liu, Bailin; Zhang, Ning; Wen, Yikai; Jin, Xin; Yang, Jiangwei; Si, Huaijun; Wang, Di

    2015-03-20

    Potato tuber dormancy release is a critical development process that allows potato to produce new plant. The first Illumina RNA sequencing to generate the expressed mRNAs at dormancy tuber (DT), dormancy release tuber (DRT) and sprouting tuber (ST) was performed. We identified 26,639 genes including 5,912 (3,450 up-regulated while 2,462 down-regulated) and 3,885 (2,141 up-regulated while 1,744 down-regulated) genes were differentially expressed from DT vs DRT and DRT vs ST. The RNA-Seq results were further verified using qRT-PCR. We found reserve mobilization events were activated before the bud emergence (DT vs DRT) and highlighted after dormancy release (DRT vs ST). Overexpressed genes related to metabolism of auxin, gibberellic acid, cytokinin and barssinosteriod were dominated in DT vs DRT, whereas overexpressed genes involved in metabolism of ethylene, jasmonate and salicylate were prominent in DRT vs ST. Various histone and cyclin isoforms associated genes involved in cell division/cycle were mainly up-regulated in DT vs DRT. Dormancy release process was also companied by stress response and redox regulation, those genes related to biotic stress, cell wall and second metabolism was preferentially overexpressed in DRT vs ST, which might accelerate dormancy breaking and sprout outgrowth. The metabolic processes activated during tuber dormancy release were also supported by plant seed models. These results represented the first comprehensive picture of a large number of genes involved in tuber dormancy release process. PMID:25661840

  3. A molecular framework for seasonal growth-dormancy regulation in perennial plants.

    PubMed

    Shim, Donghwan; Ko, Jae-Heung; Kim, Won-Chan; Wang, Qijun; Keathley, Daniel E; Han, Kyung-Hwan

    2014-01-01

    The timing of the onset and release of dormancy impacts the survival, productivity and spatial distribution of temperate horticultural and forestry perennials and is mediated by at least three main regulatory programs involving signal perception and processing by phytochromes (PHYs) and PHY-interacting transcription factors (PIFs). PIF4 functions as a key regulator of plant growth in response to both external and internal signals. In poplar, the expression of PIF4 and PIF3-LIKE1 is upregulated in response to short days, while PHYA and PHYB are not regulated at the transcriptional level. Integration of light and environmental signals is achieved by gating the expression and transcriptional activity of PIF4. During this annual cycle, auxin promotes the degradation of Aux/IAA transcriptional repressors through the SKP-Cullin-F-boxTIR1 complex, relieving the repression of auxin-responsive genes by allowing auxin response factors (ARFs) to activate the transcription of auxin-responsive genes involved in growth responses. Analyses of transcriptome changes during dormancy transitions have identified MADS-box transcription factors associated with endodormancy induction. Previous studies show that poplar dormancy-associated MADS-box (DAM) genes PtMADS7 and PtMADS21 are differentially regulated during the growth-dormancy cycle. Endodormancy may be regulated by internal factors, which are specifically localized in buds. PtMADS7/PtMADS21 may function as an internal regulator in poplar. The control of flowering time shares certain regulatory hierarchies with control of the dormancy/growth cycle. However, the particularities of different stages of the dormancy/growth cycle warrant comprehensive approaches to identify the causative genes for the entire cycle. A growing body of knowledge also indicates epigenetic regulation plays a role in these processes in perennial horticultural and forestry plants. The increased knowledge contributes to better understanding of the dormancy process and consequently to precise manipulation of dormancy-related horticultural traits, such as flowering time. PMID:26504555

  4. A molecular framework for seasonal growth-dormancy regulation in perennial plants

    PubMed Central

    Shim, Donghwan; Ko, Jae-Heung; Kim, Won-Chan; Wang, Qijun; Keathley, Daniel E; Han, Kyung-Hwan

    2014-01-01

    The timing of the onset and release of dormancy impacts the survival, productivity and spatial distribution of temperate horticultural and forestry perennials and is mediated by at least three main regulatory programs involving signal perception and processing by phytochromes (PHYs) and PHY-interacting transcription factors (PIFs). PIF4 functions as a key regulator of plant growth in response to both external and internal signals. In poplar, the expression of PIF4 and PIF3-LIKE1 is upregulated in response to short days, while PHYA and PHYB are not regulated at the transcriptional level. Integration of light and environmental signals is achieved by gating the expression and transcriptional activity of PIF4. During this annual cycle, auxin promotes the degradation of Aux/IAA transcriptional repressors through the SKP–Cullin-F–boxTIR1 complex, relieving the repression of auxin-responsive genes by allowing auxin response factors (ARFs) to activate the transcription of auxin-responsive genes involved in growth responses. Analyses of transcriptome changes during dormancy transitions have identified MADS-box transcription factors associated with endodormancy induction. Previous studies show that poplar dormancy-associated MADS-box (DAM) genes PtMADS7 and PtMADS21 are differentially regulated during the growth-dormancy cycle. Endodormancy may be regulated by internal factors, which are specifically localized in buds. PtMADS7/PtMADS21 may function as an internal regulator in poplar. The control of flowering time shares certain regulatory hierarchies with control of the dormancy/growth cycle. However, the particularities of different stages of the dormancy/growth cycle warrant comprehensive approaches to identify the causative genes for the entire cycle. A growing body of knowledge also indicates epigenetic regulation plays a role in these processes in perennial horticultural and forestry plants. The increased knowledge contributes to better understanding of the dormancy process and consequently to precise manipulation of dormancy-related horticultural traits, such as flowering time. PMID:26504555

  5. Physiological processes during winter dormancy and their ecological significance

    SciTech Connect

    Havranek, W.M.; Tranquillini, W.

    1995-07-01

    Lengthy and severe winters require that trees in the forests of boreal and mountain zones undergo winter dormancy. Physiologically, a high resistance to subfreezing temperatures and concomitant dehydration are necessary. To accomplish this dormancy, both physiological and structural changes are needed at the cellular level that require induction by endogenous and photoperiodic control early in autumn. Endogenous rhythmicity promotes cold hardening in early autumn and the persistence of hardiness throughout the winter. Numerous physiological functions are maintained at a reduced level, or become completely inhibited during true winter dormancy. Winter hardiness also includes the capability to minimize water loss effectively when water uptake is severely impeded or impossible. Anatomical features such as tracheids act to minimize xylem embolism during frequent freeze-thaw cycles, and {open_quotes}crown{close_quotes} tissues enable buds to stay in a dehydrated and, thus, more resistant state during winter. Both these structural features are adaptations that contribute to the dominance of conifers in cold climates. Interestingly, deciduous tree species rather than evergreen conifers dominate in the most severe winter climates, although it is not clear whether limitations during winter, during the summer growth period, or during both are most limiting to conifer tree ecology. Additional work that evaluates the importance of winter and summer growth restriction, and their interaction, is needed before a comprehensive understanding of conifer tree ecophysiology will be possible.

  6. Increase in ACC oxidase levels and activities during paradormancy release of leafy spurge (Euphorbia esula) buds

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The plant hormone ethylene is known to affect various developmental processes including dormancy and growth. Yet, little information is available about ethylene’s role during paradormancy break in adventitious buds of leafy spurge. In this study, we examined changes in ethylene evolution and the eth...

  7. Effects of Oxygen and Respiratory Inhibitors on Induction and Release of Dormancy in Aerial Tubers of Begonia evansiana.

    PubMed

    Esashi, Y

    1973-03-01

    Effects of O(2) and some respiratory inhibitors on the induction and release of bud dormancy were examined with the aerial tubers of different ages of Begonia evansiana Andr. Oxygen was needed not only for tuber sprouting but also during the chilling process at 2 to 5 C to break tuber dormancy. If the mature tubers were exposed to blue light during the chilling period, their dormancy was strikingly released even by the chilling given under an O(2) concentration as low as 3%. Blue light pretreatment promoted photo-sprouting of immature tubers only when given under lower O(2) concentrations. On the other hand, red light became effective in inducing dormancy in the immature tubers and in prolonging dormancy in the mature tubers as O(2) tension was increased. This was also the case with the induction of dormancy in the immature tubers by exposing them to a lower temperature (17 C) in the dark. The development of dormancy was suppressed by 2,4-dinitrophenol, p-nitrophenol, and sodium azide. PMID:16658360

  8. Effects of Oxygen and Respiratory Inhibitors on Induction and Release of Dormancy in Aerial Tubers of Begonia evansiana

    PubMed Central

    Esashi, Y.; Nagao, M.

    1973-01-01

    Effects of O2 and some respiratory inhibitors on the induction and release of bud dormancy were examined with the aerial tubers of different ages of Begonia evansiana Andr. Oxygen was needed not only for tuber sprouting but also during the chilling process at 2 to 5 C to break tuber dormancy. If the mature tubers were exposed to blue light during the chilling period, their dormancy was strikingly released even by the chilling given under an O2 concentration as low as 3%. Blue light pretreatment promoted photo-sprouting of immature tubers only when given under lower O2 concentrations. On the other hand, red light became effective in inducing dormancy in the immature tubers and in prolonging dormancy in the mature tubers as O2 tension was increased. This was also the case with the induction of dormancy in the immature tubers by exposing them to a lower temperature (17 C) in the dark. The development of dormancy was suppressed by 2,4-dinitrophenol, p-nitrophenol, and sodium azide. PMID:16658360

  9. Transcription profiling of the chilling requirement for bud break in apples: a putative role for FLC-like genes.

    PubMed

    Porto, Diogo Denardi; Bruneau, Maryline; Perini, Pâmela; Anzanello, Rafael; Renou, Jean-Pierre; dos Santos, Henrique Pessoa; Fialho, Flávio Bello; Revers, Luís Fernando

    2015-05-01

    Apple production depends on the fulfilment of a chilling requirement for bud dormancy release. Insufficient winter chilling results in irregular and suboptimal bud break in the spring, with negative impacts on apple yield. Trees from apple cultivars with contrasting chilling requirements for bud break were used to investigate the expression of the entire set of apple genes in response to chilling accumulation in the field and controlled conditions. Total RNA was analysed on the AryANE v.1.0 oligonucleotide microarray chip representing 57,000 apple genes. The data were tested for functional enrichment, and differential expression was confirmed by real-time PCR. The largest number of differentially expressed genes was found in samples treated with cold temperatures. Cold exposure mostly repressed expression of transcripts related to photosynthesis, and long-term cold exposure repressed flavonoid biosynthesis genes. Among the differentially expressed selected candidates, we identified genes whose annotations were related to the circadian clock, hormonal signalling, regulation of growth, and flower development. Two genes, annotated as FLOWERING LOCUS C-like and MADS AFFECTING FLOWERING, showed strong differential expression in several comparisons. One of these two genes was upregulated in most comparisons involving dormancy release, and this gene's chromosomal position co-localized with the confidence interval of a major quantitative trait locus for the timing of bud break. These results indicate that photosynthesis and auxin transport are major regulatory nodes of apple dormancy and unveil strong candidates for the control of bud dormancy. PMID:25750421

  10. Roles of Endoplasmic Reticulum Stress and Unfolded Protein Response Associated Genes in Seed Stratification and Bud Endodormancy during Chilling Accumulation in Prunus persica

    PubMed Central

    Fu, Xi Ling; Xiao, Wei; Wang, Dong Ling; Chen, Min; Tan, Qiu Ping; Li, Ling; De Chen, Xiu; Gao, Dong Sheng

    2014-01-01

    Dormancy mechanisms in seeds and buds arrest growth until environmental conditions are optimal for development. A genotype-specific period of chilling is usually required to release dormancy, but the underlying molecular mechanisms are still not fully understood. To discover transcriptional pathways associated with dormancy release common to seed stratification and bud endodormancy, we explored the chilling-dependent expression of 11 genes involved in endoplasmic reticulum stress and the unfolded protein response signal pathways. We propose that endoplasmic reticulum stress and the unfolded protein response impact on seed as well as bud germination and development by chilling-dependent mechanisms. The emerging discovery of similarities between seed stratification and bud endodormancy status indicate that these two processes are probably regulated by common endoplasmic reticulum stress and unfolded protein response signalling pathways. Clarification of regulatory pathways common to both seed and bud dormancy may enhance understanding of the mechanisms underlying dormancy and breeding programs may benefit from earlier prediction of chilling requirements for uniform blooming of novel genotypes of deciduous fruit tree species. PMID:24999812

  11. Roles of endoplasmic reticulum stress and unfolded protein response associated genes in seed stratification and bud endodormancy during chilling accumulation in Prunus persica.

    PubMed

    Fu, Xi Ling; Xiao, Wei; Wang, Dong Ling; Chen, Min; Tan, Qiu Ping; Li, Ling; De Chen, Xiu; Gao, Dong Sheng

    2014-01-01

    Dormancy mechanisms in seeds and buds arrest growth until environmental conditions are optimal for development. A genotype-specific period of chilling is usually required to release dormancy, but the underlying molecular mechanisms are still not fully understood. To discover transcriptional pathways associated with dormancy release common to seed stratification and bud endodormancy, we explored the chilling-dependent expression of 11 genes involved in endoplasmic reticulum stress and the unfolded protein response signal pathways. We propose that endoplasmic reticulum stress and the unfolded protein response impact on seed as well as bud germination and development by chilling-dependent mechanisms. The emerging discovery of similarities between seed stratification and bud endodormancy status indicate that these two processes are probably regulated by common endoplasmic reticulum stress and unfolded protein response signalling pathways. Clarification of regulatory pathways common to both seed and bud dormancy may enhance understanding of the mechanisms underlying dormancy and breeding programs may benefit from earlier prediction of chilling requirements for uniform blooming of novel genotypes of deciduous fruit tree species. PMID:24999812

  12. Release of Apical Dominance in Potato Tuber Is Accompanied by Programmed Cell Death in the Apical Bud Meristem[C][W

    PubMed Central

    Teper-Bamnolker, Paula; Buskila, Yossi; Lopesco, Yael; Ben-Dor, Shifra; Saad, Inbal; Holdengreber, Vered; Belausov, Eduard; Zemach, Hanita; Ori, Naomi; Lers, Amnon; Eshel, Dani

    2012-01-01

    Potato (Solanum tuberosum) tuber, a swollen underground stem, is used as a model system for the study of dormancy release and sprouting. Natural dormancy release, at room temperature, is initiated by tuber apical bud meristem (TAB-meristem) sprouting characterized by apical dominance (AD). Dormancy is shortened by treatments such as bromoethane (BE), which mimics the phenotype of dormancy release in cold storage by inducing early sprouting of several buds simultaneously. We studied the mechanisms governing TAB-meristem dominance release. TAB-meristem decapitation resulted in the development of increasing numbers of axillary buds with time in storage, suggesting the need for autonomous dormancy release of each bud prior to control by the apical bud. Hallmarks of programmed cell death (PCD) were identified in the TAB-meristems during normal growth, and these were more extensive when AD was lost following either extended cold storage or BE treatment. Hallmarks included DNA fragmentation, induced gene expression of vacuolar processing enzyme1 (VPE1), and elevated VPE activity. VPE1 protein was semipurified from BE-treated apical buds, and its endogenous activity was fully inhibited by a cysteinyl aspartate-specific protease-1-specific inhibitor N-Acetyl-Tyr-Val-Ala-Asp-CHO (Ac-YVAD-CHO). Transmission electron microscopy further revealed PCD-related structural alterations in the TAB-meristem of BE-treated tubers: a knob-like body in the vacuole, development of cytoplasmic vesicles, and budding-like nuclear segmentations. Treatment of tubers with BE and then VPE inhibitor induced faster growth and recovered AD in detached and nondetached apical buds, respectively. We hypothesize that PCD occurrence is associated with the weakening of tuber AD, allowing early sprouting of mature lateral buds. PMID:22362870

  13. RNA-Seq-based transcriptome analysis of dormant flower buds of Chinese cherry (Prunus pseudocerasus).

    PubMed

    Zhu, Youyin; Li, Yongqiang; Xin, Dedong; Chen, Wenrong; Shao, Xu; Wang, Yue; Guo, Weidong

    2015-01-25

    Bud dormancy is a critical biological process allowing Chinese cherry (Prunus pseudocerasus) to survive in winter. Due to the lake of genomic information, molecular mechanisms triggering endodormancy release in flower buds have remained unclear. Hence, we used Illumina RNA-Seq technology to carry out de novo transcriptome assembly and digital gene expression profiling of flower buds. Approximately 47million clean reads were assembled into 50,604 sequences with an average length of 837bp. A total of 37,650 unigene sequences were successfully annotated. 128 pathways were annotated by Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis, and metabolic, biosynthesis of second metabolite and plant hormone signal transduction accounted for higher percentage in flower bud. In critical period of endodormancy release, 1644, significantly differentially expressed genes (DEGs) were identified from expression profile. DEGs related to oxidoreductase activity were especially abundant in Gene Ontology (GO) molecular function category. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis demonstrated that DEGs were involved in various metabolic processes, including phytohormone metabolism. Quantitative real-time PCR (qRT-PCR) analysis indicated that levels of DEGs for abscisic acid and gibberellin biosynthesis decreased while the abundance of DEGs encoding their degradation enzymes increased and GID1 was down-regulated. Concomitant with endodormancy release, MADS-box transcription factors including P. pseudocerasus dormancy-associated MADS-box (PpcDAM), Agamous-like2, and APETALA3-like genes, shown remarkably epigenetic roles. The newly generated transcriptome and gene expression profiling data provide valuable genetic information for revealing transcriptomic variation during bud dormancy in Chinese cherry. The uncovered data should be useful for future studies of bud dormancy in Prunus fruit trees lacking genomic information. PMID:25447903

  14. Seed dormancy in Mexican teosinte

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Seed dormancy in wild Zea species may affect fitness and relate to ecological adaptation. The primary objective of this study was to characterize the variation in seed germination of the wild species of the genus Zea that currently grow in Mexico, and to relate this variation to their ecological zon...

  15. Overexpression of a peach CBF gene in apple: a model for understanding the integration of growth, dormancy, and cold hardiness in woody plants

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The timing of cold acclimation and de-acclimation, dormancy, and bud break play an integral role in the life cycle of woody plants. The molecular events that regulate these parameters have been the subject of much study, however, in most studies these events have been investigated independently of ...

  16. Molecular and biochemical mechanisms associated with dormancy and drought tolerance in the desert legume Retama raetam.

    PubMed

    Pnueli, Lilach; Hallak-Herr, Elza; Rozenberg, Mira; Cohen, Mira; Goloubinoff, Pierre; Kaplan, Aaron; Mittler, Ron

    2002-08-01

    Dormancy is an important developmental program allowing plants to withstand extended periods of extreme environmental conditions, such as low temperature or drought. Seed dormancy, bud dormancy and desiccation tolerance have been extensively studied, but little is known about the mechanisms involved in the dormancy of drought-tolerant plants, key to the survival of many plant species in arid and semi-arid environments. Subtractive PCR cloning of cDNAs from Retama raetam, a C3 drought-tolerant legume, revealed that dormancy in this plant is accompanied by the accumulation of transcripts encoding a pathogenesis-related, PR-10-like protein; a low temperature-inducible dehydrin; and a WRKY transcription factor. In contrast, non-dormant plants subjected to stress conditions contained transcripts encoding a cytosolic small heat-shock protein, HSP18; an ethylene-response transcriptional co-activator; and an early light-inducible protein. Physiological and biochemical analysis of Rubisco activity and protein in dormant and non-dormant tissues suggested a novel post-translational mechanism of regulation that may be controlled by the redox status of cells. Ultrastructural analysis of dormant plants revealed that air spaces of photosynthetic tissues contained an extracellular matrix that may function to prevent water loss. The cytosol of dormant cells appeared to be in a glassy state, limiting metabolic activity. A combination of biochemical, molecular and structural mechanisms, in association with metabolic suppression, may be key to the extreme drought tolerance of R. raetam and its acclimation to the desert ecosystem. These may enable plants to withstand long periods of drought, as well as rapidly to exit dormancy upon rainfall. PMID:12164811

  17. Seed dormancy and ABA signaling

    PubMed Central

    del Carmen Rodrguez-Gacio, Mara; Matilla-Vzquez, Miguel A

    2009-01-01

    The seed is an important organ in higher plants, it is an important organ for plant survival and species dispersion. The transition between seed dormancy and germination represents a critical stage in the plant life cycle and it is an important ecological and commercial trait. A dynamic balance of synthesis and catabolism of two antagonistic hormones, abscisic acid (ABA) and giberellins (GAs), controls the equilibrium between seed dormancy and germination. Embryonic ABA plays a central role in induction and maintenance of seed dormancy and also inhibits the transition from embryonic to germination growth. Therefore, the ABA metabolism must be highly regulated at both temporal and spatial levels during phase of dessication tolerance. On the other hand, the ABA levels do not depend exclusively on the seeds because sometimes it becomes a strong sink and imports it from the roots and rhizosphere through the xylem and/or phloem. These events are discussed in depth here. Likewise, the role of some recently characterized genes belonging to seeds of woody species and related to ABA signaling are also included. Finally, although four possible ABA receptors have been reported, not much is known about how they mediate ABA signaling transduction. However, new publications seem to show that almost all these receptors lack several properties to consider them as such. PMID:19875942

  18. EARLY BUD-BREAK1 (EBB1) defines a conserved mechanism for control of bud-break in woody perennials.

    PubMed

    Busov, Victor; Carneros, Elena; Yakovlev, Igor

    2016-02-01

    Bud-break is an environmentally and economically important trait in trees, shrubs and vines from temperate latitudes. Poor synchronization of bud-break timing with local climates can lead to frost injuries, susceptibility to pests and pathogens and poor crop yields in fruit trees and vines. The rapid climate changes outpace the adaptive capacities of plants to respond through natural selection. This is particularly true for trees which have long generation cycle and thus the adaptive changes are significantly delayed. Therefore, to devise appropriate breeding and conservation strategies, it is imperative to understand the molecular underpinnings that govern dormancy mechanisms. We have recently identified and characterized the poplar EARLY BUD-BREAK 1 (EBB1) gene. EBB1 is a positive regulator of bud-break and encodes a transcription factor from the AP2/ERF family. Here, using comparative and functional genomics approaches we show that EBB1 function in regulation of bud-break is likely conserved across wide range of woody perennial species with importance to forestry and agriculture. PMID:26317150

  19. Transcript Profiling of Paoenia ostii during Artificial Chilling Induced Dormancy Release Identifies Activation of GA Pathway and Carbohydrate Metabolism

    PubMed Central

    Liu, Chunying; Zhang, Yang; Zheng, Guosheng

    2013-01-01

    Endo-dormant flower buds must pass through a period of chilling to reinitiate growth and subsequent flowering, which is a major obstacle to the forcing culture of tree peony in winter. Customized cDNA microarray (8×15 K element) was used to investigate gene expression profiling in tree peony ‘Feng Dan Bai’ buds during 24 d chilling treatment at 0–4°C. According to the morphological changes after the whole plants were transferred to green house, endo-dormancy was released after 18 d chilling treatment, and prolonged chilling treatment increased bud break rate. Pearson correlation hierarchical clustering of sample groups was highly consistent with the dormancy transitions revealed by morphological changes. Totally 3,174 significantly differentially-expressed genes (P<0.05) were observed through endo-dormancy release process, of which the number of up-regulated (1,611) and that of down-regulated (1,563) was almost the same. Functional annotation of differentially-expressed genes revealed that cellular process, metabolic process, response to stimulus, regulation of biological process and development process were well-represented. Hierarchical clustering indicated that activation of genes involved in carbohydrate metabolism (Glycolysis, Citrate cycle and Pentose phosphate pathway), energy metabolism and cell growth. Based on the results of GO analysis, totally 51 probes presented in the microarray were associated with GA response and GA signaling pathway, and 22 of them were differently expressed. The expression profiles also revealed that the genes of GA biosynthesis, signaling and response involved in endo-dormancy release. We hypothesized that activation of GA pathway played a central role in the regulation of dormancy release in tree peony. PMID:23405132

  20. Coordinated Expression of FLOWERING LOCUS T and DORMANCY ASSOCIATED MADS-BOX-Like Genes in Leafy Spurge.

    PubMed

    Hao, Xinyuan; Chao, Wun; Yang, Yajun; Horvath, David

    2015-01-01

    Leafy spurge (Euphorbia esula L.) is a noxious perennial weed that produces underground adventitious buds, which are crucial for generating new vegetative shoots following periods of freezing temperatures or exposure to various control measures. It is also capable of flowering and producing seeds, but requires vernalization in some cases. DORMANCY ASSOCIATED MADS-BOX (DAM) genes have been proposed to play a direct role in the transition to winter-induced dormancy and maintenance through regulation of the FLOWERING LOCUS T (FT) gene, which also is likely involved in the vernalization process. To explore the regulation of FT and DAM during dormancy transitions in leafy spurge, the transcript accumulation of two previously cloned DAM splice variants and two different previously cloned FT genes was characterized. Under long-photoperiods (16 h light), both DAM and FT transcripts accumulate in a diurnal manner. Tissue specific expression patterns indicated the tissues with high DAM expression had low FT expression and vice versa. DAM expression is detected in leaves, stems, shoot tips, and crown buds. FT transcripts were detected mainly in leaves and flowers. Under dormancy inducing conditions, DAM and FT genes had an inverse expression pattern. Additionally, chromatin immunoprecipitation assays were performed using DAM-like protein specific antibodies to demonstrate that DAM or related proteins likely bind to cryptic and/or conserved CArG boxes in the promoter regions of FT genes isolated from endodormant crown buds. These results are consistent with the hypothesis that DAM proteins play a crucial role in leafy spurge dormancy transition and maintenance, potentially by negatively regulating the expression of FT. PMID:25961298

  1. Coordinated Expression of FLOWERING LOCUS T and DORMANCY ASSOCIATED MADS-BOX-Like Genes in Leafy Spurge

    PubMed Central

    Hao, Xinyuan; Chao, Wun; Yang, Yajun; Horvath, David

    2015-01-01

    Leafy spurge (Euphorbia esula L.) is a noxious perennial weed that produces underground adventitious buds, which are crucial for generating new vegetative shoots following periods of freezing temperatures or exposure to various control measures. It is also capable of flowering and producing seeds, but requires vernalization in some cases. DORMANCY ASSOCIATED MADS-BOX (DAM) genes have been proposed to play a direct role in the transition to winter-induced dormancy and maintenance through regulation of the FLOWERING LOCUS T (FT) gene, which also is likely involved in the vernalization process. To explore the regulation of FT and DAM during dormancy transitions in leafy spurge, the transcript accumulation of two previously cloned DAM splice variants and two different previously cloned FT genes was characterized. Under long-photoperiods (16 h light), both DAM and FT transcripts accumulate in a diurnal manner. Tissue specific expression patterns indicated the tissues with high DAM expression had low FT expression and vice versa. DAM expression is detected in leaves, stems, shoot tips, and crown buds. FT transcripts were detected mainly in leaves and flowers. Under dormancy inducing conditions, DAM and FT genes had an inverse expression pattern. Additionally, chromatin immunoprecipitation assays were performed using DAM-like protein specific antibodies to demonstrate that DAM or related proteins likely bind to cryptic and/or conserved CArG boxes in the promoter regions of FT genes isolated from endodormant crown buds. These results are consistent with the hypothesis that DAM proteins play a crucial role in leafy spurge dormancy transition and maintenance, potentially by negatively regulating the expression of FT. PMID:25961298

  2. 44. INTERIOR FIRST FLOOR, ENTRANCE HALL, EAST (FRONT) ENTRANCE DOOR ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    44. INTERIOR FIRST FLOOR, ENTRANCE HALL, EAST (FRONT) ENTRANCE DOOR FROM THE WEST - Mark Twain House, 351 Farmington Avenue (corrected from original address of 531 Farmington Avenue), Hartford, Hartford County, CT

  3. Detail of secondary entrance south of main entrance on east ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Detail of secondary entrance south of main entrance on east elevation; camera facing west. - Mare Island Naval Shipyard, Mechanics Shop, Waterfront Avenue, west side between A Street & Third Street, Vallejo, Solano County, CA

  4. RNAi in budding yeast

    PubMed Central

    Mower, Jeffrey P.; Wolfe, Kenneth H.; Fink, Gerald R.; Bartel, David P.

    2013-01-01

    RNAi, a gene-silencing pathway triggered by double-stranded RNA, is conserved in diverse eukaryotic species but has been lost in the model budding yeast, Saccharomyces cerevisiae. Here, we show that RNAi is present in other budding-yeast species, including Saccharomyces castellii and Candida albicans. These species use noncanonical Dicer proteins to generate siRNAs, which mostly correspond to transposable elements and Y’ subtelomeric repeats. In S. castellii, RNAi mutants are viable but have excess Y’ mRNA levels. In S. cerevisiae, introducing Dicer and Argonaute of S. castellii restores RNAi, and the reconstituted pathway silences endogenous retrotransposons. These results identify a novel class of Dicer proteins, bring the tool of RNAi to the study of budding yeasts, and bring the tools of budding yeast to the study of RNAi. PMID:19745116

  5. Hormone Metabolism During Potato Tuber Dormancy

    Technology Transfer Automated Retrieval System (TEKTRAN)

    At harvest and for an indeterminate period thereafter potato tubers will not sprout and are physiologically dormant. The length of tuber dormancy is dependent on cultivar and pre- and postharvest environmental conditions. Plant hormones have been shown to be involved in all phases of dormancy prog...

  6. Genome-wide transcriptome profiling provides insights into floral bud development of summer-flowering Camellia azalea.

    PubMed

    Fan, Zhengqi; Li, Jiyuan; Li, Xinlei; Wu, Bin; Wang, Jiangying; Liu, Zhongchi; Yin, Hengfu

    2015-01-01

    The transition from vegetative to reproductive growth in woody perennials involves pathways controlling flowering timing, bud dormancy and outgrowth in responses to seasonal cues. However little is known about the mechanism governing the adaptation of signaling pathways to environmental conditions in trees. Camellia azalea is a rare species in this genus flowering during summer, which provides a unique resource for floral timing breeding. Here we reported a comprehensive transcriptomics study to capture the global gene profiles during floral bud development in C. azalea. We examined the genome-wide gene expression between three developmental stages including floral bud initiation, floral organ differentiation and bud outgrowth, and identified nine co-expression clusters with distinctive patterns. Further, we identified the differential expressed genes (DEGs) during development and characterized the functional properties of DEGs by Gene Ontology analysis. We showed that transition from floral bud initiation to floral organ differentiation required changes of genes in flowering timing regulation, while transition to floral bud outgrowth was regulated by various pathways such as cold and light signaling, phytohormone pathways and plant metabolisms. Further analyses of dormancy associated MADS-box genes revealed that SVP- and AGL24- like genes displayed distinct expression patterns suggesting divergent roles during floral bud development. PMID:25978548

  7. Genome-wide transcriptome profiling provides insights into floral bud development of summer-flowering Camellia azalea

    PubMed Central

    Fan, Zhengqi; Li, Jiyuan; Li, Xinlei; Wu, Bin; Wang, Jiangying; Liu, Zhongchi; Yin, Hengfu

    2015-01-01

    The transition from vegetative to reproductive growth in woody perennials involves pathways controlling flowering timing, bud dormancy and outgrowth in responses to seasonal cues. However little is known about the mechanism governing the adaptation of signaling pathways to environmental conditions in trees. Camellia azalea is a rare species in this genus flowering during summer, which provides a unique resource for floral timing breeding. Here we reported a comprehensive transcriptomics study to capture the global gene profiles during floral bud development in C. azalea. We examined the genome-wide gene expression between three developmental stages including floral bud initiation, floral organ differentiation and bud outgrowth, and identified nine co-expression clusters with distinctive patterns. Further, we identified the differential expressed genes (DEGs) during development and characterized the functional properties of DEGs by Gene Ontology analysis. We showed that transition from floral bud initiation to floral organ differentiation required changes of genes in flowering timing regulation, while transition to floral bud outgrowth was regulated by various pathways such as cold and light signaling, phytohormone pathways and plant metabolisms. Further analyses of dormancy associated MADS-box genes revealed that SVP- and AGL24- like genes displayed distinct expression patterns suggesting divergent roles during floral bud development. PMID:25978548

  8. Latitudinal variation in sensitivity of flower bud formation to high temperature in Japanese Taraxacum officinale.

    PubMed

    Yoshie, Fumio

    2014-05-01

    Control of flowering time plays a key role in the successful range expansion of plants. Taraxacum officinale has expanded throughout Japan during the 110 years after it was introduced into a cool temperate region. The present study tested a hypothesis that there is a genetic difference in the bud formation time in relation to temperature along latitudinal gradient of T. officinale populations. In Experiment 1, plants from three populations at different latitudes (26, 36, and 43°N) were grown at three temperatures. Time to flower bud appearance did not significantly differ among the three populations when plants were grown at 14 °C, whereas it increased with increasing latitude when grown at 19 and 24 °C. Rosette diameter was not different among the populations, indicating that the variation in bud formation time reflected a difference in genetic control rather than size variation. The latitudinal variation in bud appearance time was confirmed by Experiment 2 in which plants from 17 population were used. In Experiment 3, the size of plants that exhibited late-flowering was studied to test a hypothesis that the variation in flowering time reflects dormancy of vegetative growth, but the late-flowering plants were found to continue growth, indicating that vegetative dormancy was not the cause of the variation. The results clearly indicate that the degree of suppression of flower bud formation at high temperature decreases with latitude from north to south, which is under genetic control. PMID:24585133

  9. Gladiolus hybridus ABSCISIC ACID INSENSITIVE 5 (GhABI5) is an important transcription factor in ABA signaling that can enhance Gladiolus corm dormancy and Arabidopsis seed dormancy

    PubMed Central

    Wu, Jian; Seng, Shanshan; Sui, Juanjuan; Vonapartis, Eliana; Luo, Xian; Gong, Benhe; Liu, Chen; Wu, Chenyu; Liu, Chao; Zhang, Fengqin; He, Junna; Yi, Mingfang

    2015-01-01

    The phytohormone abscisic acid (ABA) regulates plant development and is crucial for abiotic stress response. In this study, cold storage contributes to reducing endogenous ABA content, resulting in dormancy breaking of Gladiolus. The ABA inhibitor fluridone also promotes germination, suggesting that ABA is an important hormone that regulates corm dormancy. Here, we report the identification and functional characterization of the Gladiolus ABI5 homolog (GhABI5), which is a basic leucine zipper motif transcriptional factor (TF). GhABI5 is expressed in dormant vegetative organs (corm, cormel, and stolon) as well as in reproductive organs (stamen), and it is up-regulated by ABA or drought. Complementation analysis reveals that GhABI5 rescues the ABA insensitivity of abi5-3 during seed germination and induces the expression of downstream ABA response genes in Arabidopsis thaliana (EM1, EM6, and RD29B). Down-regulation of GhABI5 in dormant cormels via virus induced gene silence promotes sprouting and reduces the expression of downstream genes (GhLEA and GhRD29B). The results of this study reveal that GhABI5 regulates bud dormancy (vegetative organ) in Gladiolus in addition to its well-studied function in Arabidopsis seeds (reproductive organ). PMID:26579187

  10. Mycobacterium tuberculosis: Success through dormancy

    PubMed Central

    Gengenbacher, Martin; Kaufmann, Stefan H. E.

    2012-01-01

    Tuberculosis (TB) remains a major health threat, killing near to 2 million individuals around this globe, annually. The sole vaccine developed almost a century ago, provides limited protection only during childhood. After decades without the introduction of new antibiotics, several candidates are currently undergoing clinical investigation. Curing TB requires prolonged combination chemotherapy with several drugs. Moreover, monitoring the success of therapy is questionable due to the lack of reliable biomarkers. To substantially improve the situation, a detailed understanding of the crosstalk between human host and the pathogen Mycobacterium tuberculosis (Mtb) is vital. Principally, Mtb’s enormous success is based on three capacities: First, reprogramming of macrophages after primary infection/phagocytosis in order to prevent its own destruction; second, initiating the formation of well-organized granulomas, comprising different immune cells to create a confined environment for the host–pathogen standoff; third, the capability to shut down its own central metabolism, terminate replication and thereby transit into a stage of dormancy rendering itself extremely resistant to host defense and drug treatment. Here we review the molecular mechanisms underlying these processes, draw conclusions in a working model of mycobacterial dormancy and highlight gaps in our understanding to be addressed in future research. PMID:22320122

  11. Metabolic changes upon flower bud break in Japanese apricot are enhanced by exogenous GA4.

    PubMed

    Zhuang, Weibing; Gao, Zhihong; Wen, Luhua; Huo, Ximei; Cai, Binhua; Zhang, Zhen

    2015-01-01

    Gibberellin (GA4) has a significant effect on promoting dormancy release in flower buds of Japanese apricot (Prunus mume Sieb. et Zucc). The transcriptomic and proteomic changes that occur after GA4 treatment have been reported previously; however, the metabolic changes brought about by GA4 remain unknown. The present study was undertaken to assess changes in metabolites in response to GA4 treatment, as determined using gas chromatography-mass spectrometry and principal component analysis. Fifty-five metabolites that exhibited more than two-fold differences in abundance (P < 0.05) between samples collected over time after a given treatment or between samples exposed to different treatments were studied further. These metabolites were categorized into six main groups: amino acids and their isoforms (10), amino acid derivatives (7), sugars and polyols (14), organic acids (12), fatty acids (4), and others (8). All of these groups are involved in various metabolic pathways, in particular galactose metabolism, glyoxylate and dicarboxylate metabolism, and starch and sucrose metabolism. These results suggested that energy metabolism is important at the metabolic level in dormancy release following GA4 treatment. We also found that more than 10-fold differences in abundance were observed for many metabolites, including sucrose, proline, linoleic acid, and linolenic acid, which might play important roles during the dormancy process. The current research extends our understanding of the mechanisms involved in budburst and dormancy release in response to GA4 and provides a theoretical basis for applying GA4 to release dormancy. PMID:26504583

  12. Metabolic changes upon flower bud break in Japanese apricot are enhanced by exogenous GA4

    PubMed Central

    Zhuang, Weibing; Gao, Zhihong; Wen, Luhua; Huo, Ximei; Cai, Binhua; Zhang, Zhen

    2015-01-01

    Gibberellin (GA4) has a significant effect on promoting dormancy release in flower buds of Japanese apricot (Prunus mume Sieb. et Zucc). The transcriptomic and proteomic changes that occur after GA4 treatment have been reported previously; however, the metabolic changes brought about by GA4 remain unknown. The present study was undertaken to assess changes in metabolites in response to GA4 treatment, as determined using gas chromatography–mass spectrometry and principal component analysis. Fifty-five metabolites that exhibited more than two-fold differences in abundance (P < 0.05) between samples collected over time after a given treatment or between samples exposed to different treatments were studied further. These metabolites were categorized into six main groups: amino acids and their isoforms (10), amino acid derivatives (7), sugars and polyols (14), organic acids (12), fatty acids (4), and others (8). All of these groups are involved in various metabolic pathways, in particular galactose metabolism, glyoxylate and dicarboxylate metabolism, and starch and sucrose metabolism. These results suggested that energy metabolism is important at the metabolic level in dormancy release following GA4 treatment. We also found that more than 10-fold differences in abundance were observed for many metabolites, including sucrose, proline, linoleic acid, and linolenic acid, which might play important roles during the dormancy process. The current research extends our understanding of the mechanisms involved in budburst and dormancy release in response to GA4 and provides a theoretical basis for applying GA4 to release dormancy. PMID:26504583

  13. Induction of endodormancy in crown buds of leafy spurge (Euphorbia esula L.) implicates a role for ethylene and cross-talk between photoperiod and temperature

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Leafy spurge is a model for studying well-defined phases of dormancy in underground adventitious buds (UABs) of herbaceous perennial weeds, which is a primary factor facilitating their escape from conventional control measures. A 12-week ramp down in both temperature (27°C ' 10°C) and photoperiod (1...

  14. Overexpression of a peach CBF gene in apple: a model for understanding the integration of growth, dormancy, and cold hardiness in woody plants.

    PubMed

    Wisniewski, Michael; Norelli, John; Artlip, Timothy

    2015-01-01

    The timing of cold acclimation and deacclimation, dormancy, and budbreak play an integral role in the life cycle of woody plants. The molecular events that regulate these parameters have been the subject of much study, however, in most studies these events have been investigated independently of each other. Ectopic expression of a peach CBF (PpCBF1) in apple increases the level of both non-acclimated and acclimated freezing tolerance relative to the non-transformed control, and also inhibits growth, induces early bud set and leaf senescence, and delays bud break in the spring. The current study examined differences in the seasonal expression of genes (CBF, DAM, RGL, and EBB) that have been reported to be associated with freezing tolerance, dormancy, growth, and bud break, respectively, in the PpCBF1 T166 transgenic apple line and the non-transformed M.26 control. Results indicated that expression of several of these key genes, including MdDAM, MdRGL, and MdEBB was altered in transgenic T166 trees relative to non-transformed M.26 trees. In particular, several putative MdDAM genes, associated with the dormancy-cycle in other species of woody plants in the Rosaceae, exhibited different patterns of expression in the T166 vs. M.26 trees. Additionally, for the first time a putative APETALA2/Ethylene-responsive transcription factor, originally described in poplar and shown to regulate the timing of bud break, was shown to be associated with the timing of bud break in apple. Since the overexpression of PpCBF1 in apple results in a dramatic alteration in cold acclimation, dormancy, and growth, this transgenic line (T166) may represent a useful model for studying the integration of these seasonal life-cycle parameters. PMID:25774159

  15. Overexpression of a peach CBF gene in apple: a model for understanding the integration of growth, dormancy, and cold hardiness in woody plants

    PubMed Central

    Wisniewski, Michael; Norelli, John; Artlip, Timothy

    2015-01-01

    The timing of cold acclimation and deacclimation, dormancy, and budbreak play an integral role in the life cycle of woody plants. The molecular events that regulate these parameters have been the subject of much study, however, in most studies these events have been investigated independently of each other. Ectopic expression of a peach CBF (PpCBF1) in apple increases the level of both non-acclimated and acclimated freezing tolerance relative to the non-transformed control, and also inhibits growth, induces early bud set and leaf senescence, and delays bud break in the spring. The current study examined differences in the seasonal expression of genes (CBF, DAM, RGL, and EBB) that have been reported to be associated with freezing tolerance, dormancy, growth, and bud break, respectively, in the PpCBF1 T166 transgenic apple line and the non-transformed M.26 control. Results indicated that expression of several of these key genes, including MdDAM, MdRGL, and MdEBB was altered in transgenic T166 trees relative to non-transformed M.26 trees. In particular, several putative MdDAM genes, associated with the dormancy-cycle in other species of woody plants in the Rosaceae, exhibited different patterns of expression in the T166 vs. M.26 trees. Additionally, for the first time a putative APETALA2/Ethylene-responsive transcription factor, originally described in poplar and shown to regulate the timing of bud break, was shown to be associated with the timing of bud break in apple. Since the overexpression of PpCBF1 in apple results in a dramatic alteration in cold acclimation, dormancy, and growth, this transgenic line (T166) may represent a useful model for studying the integration of these seasonal life-cycle parameters. PMID:25774159

  16. "Bud, Not Buddy."

    ERIC Educational Resources Information Center

    Brodie, Carolyn S.

    2002-01-01

    Discusses the award-winning book "Bud, Not Buddy" written by Christopher Paul Curtis. Lists different versions of the book; suggests learning activities; lists sources for biographical information and interviews with Curtis, teacher guides, professional articles, and other Depression era novels; and provides a citation for the author's Newberry…

  17. Seed dormancy distribution: explanatory ecological factors

    PubMed Central

    Wagmann, Kristen; Hautekèete, Nina-Coralie; Piquot, Yves; Meunier, Cécile; Schmitt, S. Eric; Van Dijk, Henk

    2012-01-01

    Background and Aims Knowledge of those traits that vary with latitude should be helpful in predicting how they may evolve locally under climate change. In the sea beet Beta vulgaris ssp. maritima, seed dormancy largely controls the timing of germination, is highly heritable and varies geographically; it is therefore thought to be selected by climate. The aim here was to characterize the variation in seed dormancy among sea beet populations across the French distribution area, as well as the ecological factors in situ that are correlated with and that could therefore select for seed dormancy. The relative importance of genetic inheritance vs. non-genetic variation is also evaluated. Methods The proportions of dormant seeds from 85 natural populations encompassing different climates over the whole French distribution area were measured under controlled conditions. Germination phenology was observed in a common garden experiment. Dormancy variation of seeds collected in situ was compared with that of seeds collected on plants grown in the greenhouse. Key Results The proportions of dormant seeds in the greenhouse were highly variable, covering almost the entire range from 0 to 1, and followed a geographical pattern from lower dormancy at high latitudes to high dormancy at low latitudes. The distribution of dormancy was positively correlated with yearly temperatures, especially summer temperatures. Minimum temperatures in winter did not significantly explain the trait variation. The genetic component of the total variation was significant and is probably completed by an important adjustment to the local conditions brought about by maternal adaptive phenotypic plasticity. Conclusions Dormancy in sea beet could be interpreted as a way to limit summer germination and spread germination over the first autumn and spring or following autumns. This highly heritable trait has the potential to evolve in the relatively near future because of climate change. PMID:22952378

  18. EARLY ENTRANCE COPRODUCTION PLANT

    SciTech Connect

    Chi M. Ho; Robert A. Battista; Ashok Anand; Kenneth Yackly

    2003-07-22

    The overall objective of this project is the three phase development of an Early Entrance Coproduction Plant (EECP) which uses petroleum coke to produce at least one product from at least two of the following three categories: (1) electric power (or heat), (2) fuels, and (3) chemicals using ChevronTexaco's proprietary gasification technology. The object of phase 1 is to determine the feasibility and define the concept for the EECP located at a specific site; develop a Research, Development, and Testing (RD and T) Plan to mitigate technical risks and barriers; and prepare a Preliminary Project Financing Plan. The objective of Phase 2 is to implement the work as outlined in the Phase 1 RD and T Plan to enhance the development and commercial acceptance of coproduction technology. The objective of Phase 3 is to develop an engineering design package and a financing and testing plan for an EECP located at a specific site.

  19. Genetic analysis of embryo dormancy. Final report

    SciTech Connect

    Galau, G.

    1998-09-01

    Primary dormancy is the inability of mature seed to immediately germinate until specific environmental stimuli are perceived that predict that future conditions will support plant growth and seed set. The analysis of abscisic acid deficient and insensitive mutants, in particular in Arabidopsis, suggests that embryo abscisic acid may be directly involved in the development of primary dormancy. Other studies implicate the continued accumulation of LEA proteins as inhibiting germination in dormant embryos. The results of these physiological, molecular and genetic approaches are complex and equivocal. There is a real need for approaches that test the separate nature of vivipary inhibition and primary dormancy and deliberately seed to decouple and dissect them. These approaches should be of help in understanding both late embryo development and primary dormancy. The approach taken here is to directly isolate mutants of Arabidopsis that appear to be deficient only in primary dormancy, that is fresh seed that germinate rapidly without the normally-required cold-stratification. The authors have isolated at least 8 independent, rapidly germinating RGM mutants of Arabidopsis. All others aspects of plant growth and development appear normal in these lines, suggesting that the rgm mutants are defective only in the establishment or maintenance of primary dormancy. At least one of these may be tagged with T-DNA. In addition, about 50 RGM isolates have been recovered from EMS-treated seed.

  20. Arabidopsis mutants with a reduced seed dormancy.

    PubMed Central

    Léon-Kloosterziel, K M; van de Bunt, G A; Zeevaart, J A; Koornneef, M

    1996-01-01

    The development of seed dormancy is an aspect of seed maturation, the last stage of seed development. To isolate mutants of Arabidopsis thaliana that are affected in this process, we selected directly for the absence of dormancy among freshly harvested M2 seeds. The screen yielded two mutants exhibiting a reduced dormancy, rdo1 and rdo2, that are specifically affected in dormancy determined by the embryo. The rdo1 and rdo2 mutants show normal levels of abscisic acid and the same sensitivity to abscisic acid, ethylene, auxin, and cytokinin as the wild type. The rdo2 mutant but not the rdo1 mutant has a reduced sensitivity to the gibberellin biosynthesis inhibitor tetcyclacis. Double-mutant analysis suggested that the RDO1 and RDO2 genes are involved in separate pathways leading to the development of dormancy. We assume that the RDO2 gene controls a step in the induction of dormancy that is most likely induced by abscisic acid and is expressed as an increase of the gibberellin requirement for germination. PMID:8587986

  1. Early Entrance Coproduction Plant

    SciTech Connect

    Mushtaq Ahmed; John H. Anderson; Earl R. Berry; Troy Raybold; Lalit S. Shah; Kenneth A. Yackly

    2004-01-26

    The overall objective of this project is the three phase development of an Early Entrance Coproduction Plant (EECP) which uses petroleum coke to produce at least one product from at least two of the following three categories: (1) electric power (or heat), (2) fuels, and (3) chemicals. The objective is to have these products produced by technologies capable of using synthesis gas derived from coal and/or other carbonaceous feedstocks. The objectives of Phase I were to determine the feasibility and define the concept for the EECP located at a specific site; develop a Research, Development, and Testing (RD&T) Plan for implementation in Phase II; and prepare a Preliminary Project Financing Plan. The objective of Phase II is to implement the work as outlined in the Phase I RD&T Plan to enhance the development and commercial acceptance of coproduction technology that produces high-value products, particularly those that are critical to our domestic fuel and power requirements. The work performed under Phase II will resolve critical knowledge and technology gaps on the integration of gasification and downstream processing to coproduce some combination of power, fuels, and chemicals from coal and/or other carbonaceous feedstocks. The objective of Phase III is to develop an engineering design package and a financing and testing plan for an EECP located at a specific site. The project's intended result is to provide the necessary technical, economic, and environmental information needed by industry to move the EECP forward to detailed design, construction, and operation.

  2. EARLY ENTRANCE COPRODUCTION PLANT

    SciTech Connect

    Mushtaq Ahmed; John H. Anderson; Earl R. Berry; Fred Brent; Ming He; Jimmy O. Ong; Mike K. Porter; Randy Roberts; Charles H. Schrader; Lalit S. Shah; Kenneth A. Yackly

    2002-11-22

    The overall objective of this project is the three phase development of an Early Entrance Coproduction Plant (EECP) which produces at least one product from at least two of the following three categories: (1) electric power (or heat), (2) fuels, and (3) chemicals. The objective is to have these products produced by technologies capable of using synthesis gas derived from coal and/or other carbonaceous feedstocks. The objective of Phase I is to determine the feasibility and define the concept for the EECP located at a specific site; develop a Research, Development, and Testing (RD&T) Plan for implementation in Phase II; and prepare a Preliminary Project Financing Plan. The objective of Phase II is to implement the work as outlined in the Phase I RD&T Plan to enhance the development and commercial acceptance of coproduction technology that produces high-value products, particularly those that are critical to our domestic fuel and power requirements. The project will resolve critical knowledge and technology gaps on the integration of gasification and downstream processing to coproduce some combination of power, fuels, and chemicals from coal and/or other carbonaceous feedstocks. The objective of Phase III is to develop an engineering design package and a financing and testing plan for an EECP located at a specific site. The project's intended result is to provide the necessary technical, economic, and environmental information needed by industry to move the EECP forward to detailed design, construction, and operation.

  3. EARLY ENTRANCE COPRODUCTION PLANT

    SciTech Connect

    Mushtaq Ahmed; John H. Anderson; Charles Benham; Earl R. Berry; Fred Brent; Belma Demirel; Ming He; Troy Raybold; Manuel E. Quintana; Lalit S. Shah; Kenneth A. Yackly

    2003-06-09

    The overall objective of this project is the three phase development of an Early Entrance Coproduction Plant (EECP) which produces at least one product from at least two of the following three categories: (1) electric power (or heat), (2) fuels, and (3) chemicals. The objective is to have these products produced by technologies capable of using synthesis gas derived from coal and/or other carbonaceous feedstocks. The objectives of Phase I were to determine the feasibility and define the concept for the EECP located at a specific site; develop a Research, Development, and Testing (RD&T) Plan for implementation in Phase II; and prepare a Preliminary Project Financing Plan. The objective of Phase II is to implement the work as outlined in the Phase I RD&T Plan to enhance the development and commercial acceptance of coproduction technology that produces high-value products, particularly those that are critical to our domestic fuel and power requirements. The project will resolve critical knowledge and technology gaps on the integration of gasification and downstream processing to coproduce some combination of power, fuels, and chemicals from coal and/or other carbonaceous feedstocks. The objective of Phase III is to develop an engineering design package and a financing and testing plan for an EECP located at a specific site. The project's intended result is to provide the necessary technical, economic, and environmental information needed by industry to move the EECP forward to detailed design, construction, and operation.

  4. EARLY ENTRANCE COPRODUCTION PLANT

    SciTech Connect

    Mushtaq Ahmed; John H. Anderson; Charles Benham; Earl R. Berry; Fred Brent; Ming He; Troy Raybold; Lalit S. Shah; Kenneth A. Yackly

    2003-09-09

    The overall objective of this project is the three phase development of an Early Entrance Coproduction Plant (EECP) which uses petroleum coke to produces at least one product from at least two of the following three categories: (1) electric power (or heat), (2) fuels, and (3) chemicals. The objective is to have these products produced by technologies capable of using synthesis gas derived from coal and/or other carbonaceous feedstocks. The objectives of Phase I were to determine the feasibility and define the concept for the EECP located at a specific site; develop a Research, Development, and Testing (RD&T) Plan for implementation in Phase II; and prepare a Preliminary Project Financing Plan. The objective of Phase II is to implement the work as outlined in the Phase I RD&T Plan to enhance the development and commercial acceptance of coproduction technology that produces high-value products, particularly those that are critical to our domestic fuel and power requirements. The project will resolve critical knowledge and technology gaps on the integration of gasification and downstream processing to coproduce some combination of power, fuels, and chemicals from coal and/or other carbonaceous feedstocks. The objective of Phase III is to develop an engineering design package and a financing and testing plan for an EECP located at a specific site. The project's intended result is to provide the necessary technical, economic, and environmental information needed by industry to move the EECP forward to detailed design, construction, and operation.

  5. EARLY ENTRANCE COPRODUCTION PLANT

    SciTech Connect

    Mushtaq Ahmed; John H. Anderson; Earl R. Berry; Troy Raybold; Lalit S. Shah; Kenneth A. Yackly

    2003-12-16

    The overall objective of this project is the three phase development of an Early Entrance Coproduction Plant (EECP) which uses petroleum coke to produce at least one product from at least two of the following three categories: (1) electric power (or heat), (2) fuels, and (3) chemicals. The objective is to have these products produced by technologies capable of using synthesis gas derived from coal and/or other carbonaceous feedstocks. The objectives of Phase I were to determine the feasibility and define the concept for the EECP located at a specific site; develop a Research, Development, and Testing (RD&T) Plan for implementation in Phase II; and prepare a Preliminary Project Financing Plan. The objective of Phase II is to implement the work as outlined in the Phase I RD&T Plan to enhance the development and commercial acceptance of coproduction technology that produces high-value products, particularly those that are critical to our domestic fuel and power requirements. The work performed under Phase II will resolve critical knowledge and technology gaps on the integration of gasification and downstream processing to coproduce some combination of power, fuels, and chemicals from coal and/or other carbonaceous feedstocks. The objective of Phase III is to develop an engineering design package and a financing and testing plan for an EECP located at a specific site. The project's intended result is to provide the necessary technical, economic, and environmental information needed by industry to move the EECP forward to detailed design, construction, and operation.

  6. EARLY ENTRANCE COPRODUCTION PLANT

    SciTech Connect

    John S. Abughazaleh; Mushtaq Ahmed; Ashok Anand; John H. Anderson; Charles Benham; Fred D. Brent; Thomas E. Chance; William K. Davis; Raymond F. Drnevich; Larry Hall; Ming He; Stephen A. Lang; Jimmy O. Ong; Sarah J. Patel; George Potoczniak; Adela G. Sanchez; Charles H. Schrader; Lalit S. Shah; Phil J. Shires; Rae Song

    2000-10-26

    The overall objective of this project is the three phase development of an Early Entrance Coproduction Plant (EECP) which produces at least one product from at least two of the following three categories: (1) electric power (or heat), (2) fuels, and (3) chemicals. The objective is to have these products produced by technologies capable of using synthesis gas derived from coal and/or other carbonaceous feedstock. The objective of Phase I is to determine the feasibility and define the concept for the EECP located at a specific site and to develop a Research, Development, and Testing Plan (RD and T) for implementation in Phase II. The objective of Phase II is to implement the RD and T as outlined in the Phase I RD and T Plan to enhance the development and commercial acceptance of coproduction technology that produces high-value products, particularly those that are critical to our domestic fuel and power requirements. The project will resolve critical knowledge and technology gaps on the integration of gasification and downstream processing to coproduce some combination of power, fuels, and chemicals from coal and other feedstocks. The objective of Phase III is to develop an engineering design package and a financing plan for an EECP located at a specific site. The project's intended result is to provide the necessary technical, economic, and environmental information that will be needed to move the EECP forward to detailed design, construction, and operation by industry.

  7. EARLY ENTRANCE COPRODUCTION PLANT

    SciTech Connect

    John S. Abughazaleh; Mushtaq Ahmed; Ashok Anand; John H. Anderson; Charles Benham; Fred D. Brent; Thomas E. Chance; William K. Davis; Raymond F. Drnevich; Larry Hall; Ming He; Stephen A. Lang; Jimmy O. Ong; Sarah J. Patel; George Potoczniak; Adela G. Sanchez; Charles H. Schrader; Lalit S. Shah; Phil J. Shires; Rae Song

    2001-02-15

    The overall objective of this project is the three phase development of an Early Entrance Coproduction Plant (EECP) which produces at least one product from at least two of the following three categories: (1) electric power (or heat), (2) fuels, and (3) chemicals. The objective is to have these products produced by technologies capable of using synthesis gas derived from coal and/or other carbonaceous feedstocks. The objective of Phase I is to determine the feasibility and define the concept for the EECP located at a specific site and to develop a Research, Development, and Testing Plan (RD and T) for implementation in Phase II. The objective of Phase II is to implement the RD and T as outlined in the Phase I RD and T Plan to enhance the development and commercial acceptance of coproduction technology that produces high-value products, particularly those that are critical to our domestic fuel and power requirements. The project will resolve critical knowledge and technology gaps on the integration of gasification and downstream processing to coproduce some combination of power, fuels, and chemicals from coal and/or other carbonaceous feedstocks. The objective of Phase III is to develop an engineering design package and a financing plan for an EECP located at a specific site. The project's intended result is to provide the necessary technical, economic, and environmental information that will be needed to move the EECP forward to detailed design, construction, and operation by industry.

  8. EARLY ENTRANCE COPRODUCTION PLANT

    SciTech Connect

    John S. Abughazaleh; Mushtaq Ahmed; Ashok Anand; John H. Anderson; Charles Benham; Fred D. Brent; Thomas E. Chance; William K. Davis; Raymond F. Drnevich; Larry Hall; Ming He; Stephen A. Lang; David Mintner; Wendy Moore; Jimmy O. Ong; George Potoczniak; Adela G. Sanchez; Charles H. Schrader; Lalit S. Shah; Kalapi D. Sheth; Phil J. Shires; Rae Song

    2001-05-17

    The overall objective of this project is the three-phase development of an Early Entrance Coproduction Plant (EECP) that produces at least one product from at least two of the following three categories: Electric power (or heat); Fuels; and Chemicals. The objective is to have these products produced by technologies capable of using synthesis gas derived from coal and/or some other carbonaceous feedstock, such as petroleum coke. The objective of Phase I was to determine the feasibility and define the concept for the EECP located at a specific site and to develop a Research, Development, and Testing (RD and T) Plan for implementation in Phase II. This objective has now been accomplished. A specific site, Motiva Refinery in Port Arthur, Texas, has been selected as the location best suited for the EECP. The accomplishments of Phase I are discussed in detail in this Phase I Concept Report. A RD and T Plan and a preliminary project financing plan have been developed and are submitted separately from this report.

  9. Sucrose is an early modulator of the key hormonal mechanisms controlling bud outgrowth in Rosa hybrida.

    PubMed

    Barbier, François; Péron, Thomas; Lecerf, Marion; Perez-Garcia, Maria-Dolores; Barrière, Quentin; Rolčík, Jakub; Boutet-Mercey, Stéphanie; Citerne, Sylvie; Lemoine, Remi; Porcheron, Benoît; Roman, Hanaé; Leduc, Nathalie; Le Gourrierec, José; Bertheloot, Jessica; Sakr, Soulaiman

    2015-05-01

    Sugar has only recently been identified as a key player in triggering bud outgrowth, while hormonal control of bud outgrowth is already well established. To get a better understanding of sugar control, the present study investigated how sugar availability modulates the hormonal network during bud outgrowth in Rosa hybrida. Other plant models, for which mutants are available, were used when necessary. Buds were grown in vitro to manipulate available sugars. The temporal patterns of the hormonal regulatory network were assessed in parallel with bud outgrowth dynamics. Sucrose determined bud entrance into sustained growth in a concentration-dependent manner. Sustained growth was accompanied by sustained auxin production in buds, and sustained auxin export in a DR5::GUS-expressing pea line. Several events occurred ahead of sucrose-stimulated bud outgrowth. Sucrose upregulated early auxin synthesis genes (RhTAR1, RhYUC1) and the auxin efflux carrier gene RhPIN1, and promoted PIN1 abundance at the plasma membrane in a pPIN1::PIN1-GFP-expressing tomato line. Sucrose downregulated both RwMAX2, involved in the strigolactone-transduction pathway, and RhBRC1, a repressor of branching, at an early stage. The presence of sucrose also increased stem cytokinin content, but sucrose-promoted bud outgrowth was not related to that pathway. In these processes, several non-metabolizable sucrose analogues induced sustained bud outgrowth in R. hybrida, Pisum sativum, and Arabidopsis thaliana, suggesting that sucrose was involved in a signalling pathway. In conclusion, we identified potential hormonal candidates for bud outgrowth control by sugar. They are central to future investigations aimed at disentangling the processes that underlie regulation of bud outgrowth by sugar. PMID:25873679

  10. Identification and analysis of phosphorylation status of proteins in dormant terminal buds of poplar

    PubMed Central

    2011-01-01

    Background Although there has been considerable progress made towards understanding the molecular mechanisms of bud dormancy, the roles of protein phosphorylation in the process of dormancy regulation in woody plants remain unclear. Results We used mass spectrometry combined with TiO2 phosphopeptide-enrichment strategies to investigate the phosphoproteome of dormant terminal buds (DTBs) in poplar (Populus simonii × P. nigra). There were 161 unique phosphorylated sites in 161 phosphopeptides from 151 proteins; 141 proteins have orthologs in Arabidopsis, and 10 proteins are unique to poplar. Only 34 sites in proteins in poplar did not match well with the equivalent phosphorylation sites of their orthologs in Arabidopsis, indicating that regulatory mechanisms are well conserved between poplar and Arabidopsis. Further functional classifications showed that most of these phosphoproteins were involved in binding and catalytic activity. Extraction of the phosphorylation motif using Motif-X indicated that proline-directed kinases are a major kinase group involved in protein phosphorylation in dormant poplar tissues. Conclusions This study provides evidence about the significance of protein phosphorylation during dormancy, and will be useful for similar studies on other woody plants. PMID:22074553

  11. EARLY ENTRANCE COPRODUCTION PLANT

    SciTech Connect

    John H. Anderson; William K. Davis; Thomas W. Sloop

    2001-03-21

    As part of the Department of Energy's (DOE) Gasification Technologies and Transportation Fuels and Chemicals programs, DOE and Texaco are partners through Cooperative Agreement DE-FC26-99FT40658 to determine the feasibility of developing, constructing and operating an Early Entrance Coproduction Plant (EECP). The overall objective of the project is the three-phase development of an EECP that produces at least one product from at least two of the following three categories: Electric power (or heat); Fuels; and Chemicals. The objective is to have these products produced by technologies capable of using synthesis gas derived from coal and/or some other carbonaceous feedstock, such as petroleum coke. The objective of Phase I was to determine the feasibility and define the concept for the EECP located at a specific site and to develop a Research, Development, and Testing (RD and T) Plan for implementation in Phase II. This objective has now been accomplished. A specific site, Motiva Refinery in Port Arthur, Texas, has been selected as the location best suited for the EECP. The specific work requirements of Phase I included: Prepare an EECP Preliminary Concept Report covering Tasks 2-8 specified in the Cooperative Agreement; Develop a Research, Development, and Testing (RD and T) Plan as specified in Task 9 of the Cooperative Agreement for implementation in Phase II; and Develop a Preliminary Project Financing Plan for the EECP Project as specified in Task 10 of the Cooperative Agreement. This document is the Preliminary Project Financing Plan for the design, construction, and operation of the EECP at the Motiva Port Arthur Refinery.

  12. On dormancy strategies in tardigrades.

    PubMed

    Guidetti, Roberto; Altiero, Tiziana; Rebecchi, Lorena

    2011-05-01

    In this review we analyze the dormancy strategies of metazoans inhabiting "hostile to life" habitats, which have a strong impact on their ecology and in particular on the traits of their life history. Tardigrades are here considered a model animal, being aquatic organisms colonizing terrestrial habitats. Tardigrades evolved a large variety of dormant stages that can be ascribed to diapause (encystment, cyclomorphosis, resting eggs) and cryptobiosis (anhydrobiosis, cryobiosis, anoxibiosis). In tardigrades, diapause and cryptobiosis can occur separately or simultaneously, consequently the adoption of one adaptive strategy is not necessarily an alternative to the adoption of the other. Encystment and cyclomorphosis are characterized by seasonal cyclic changes in morphology and physiology of the animals. They share several common features and their evolution is strictly linked to the molting process. A bet-hedging strategy with different patterns of egg hatching time has been observed in a tardigrade species. Four categories of eggs have been identified: subitaneous, delayed-hatching, abortive and diapause resting eggs, which needs a stimulus to hatch (rehydration after a period of desiccation). Cryptobiotic tardigrades are able to withstand desiccation (anhydrobiosis) and freezing (cryobiosis) at any stage of their life-cycle. This ability involves a complex array of factors working at molecular (bioprotectans), physiological and structural levels. Animal survival and the accumulation of molecular damage are related to the time spent in the cryptobiotic state, to the abiotic parameters during the cryptobiotic state, and to the conditions during initial and final phases of the process. Cryptobiosis evolved independently at least two times in tardigrades, in eutardigrades and in echiniscoids. Within each evolutionary line, the absence of cryptobiotic abilities is more related to selective pressures to local habitat adaptation than to phylogenetic relationships. The selective advantages of cryptobiosis (e.g. persistency in "hostile to life" habitats, reduction of competitors, parasites and predators, escaping in time from stressful conditions) could explain the high tardigrade species diversity and number of specimens found in habitats that dry out compared to freshwater habitats. PMID:21402076

  13. EARLY ENTRANCE COPRODUCTION PLANT

    SciTech Connect

    Fred D. Brent; Lalit Shah; Earl Berry; Charles H. Schrader; John Anderson; Ming He; James F. Stevens; Centha A. Davis; Michael Henley; Jerome Mayer; Harry Tsang; Jimell Erwin; Jennifer Adams; Michael Tillman; Chris Taylor; Marjan J. Roos; Robert F. Earhart

    2004-01-27

    The overall objective of this project is the three phase development of an Early Entrance Coproduction Plant (EECP) which uses petroleum coke to produce at least one product from at least two of the following three categories: (1) electric power (or heat), (2) fuels, and (3) chemicals using ChevronTexaco's proprietary gasification technology. The objective of Phase I is to determine the feasibility and define the concept for the EECP located at a specific site; develop a Research, Development, and Testing (RD&T) Plan to mitigate technical risks and barriers; and prepare a Preliminary Project Financing Plan. The objective of Phase II is to implement the work as outlined in the Phase I RD&T Plan to enhance the development and commercial acceptance of coproduction technology. The objective of Phase III is to develop an engineering design package and a financing and testing plan for an EECP located at a specific site. The project's intended result is to provide the necessary technical, economic, and environmental information needed by industry to move the EECP forward to detailed design, construction, and operation. The partners in this project are Texaco Energy Systems LLC or TES (a subsidiary of ChevronTexaco), General Electric (GE), Praxair, and Kellogg Brown & Root (KBR) in addition to the U.S. Department of Energy (DOE). TES is providing gasification technology and Fischer-Tropsch (F-T) technology developed by Rentech, GE is providing combustion turbine technology, Praxair is providing air separation technology, and KBR is providing engineering. Each of the EECP subsystems was assessed for technical risks and barriers. A plan was developed to mitigate the identified risks (Phase II RD&T Plan, October 2000). The potential technical and economic risks to the EECP from Task 2.5 can be mitigated by demonstrating that the end-use products derived from the upgrading of the F-T synthesis total liquid product can meet or exceed current specifications for the manufacture of ethylene and propylene chemicals from F-T naphtha, for the generation of hydrogen from F-T naphtha to power fuel cells, for direct blending of F-T diesels into transportation fuels, for the conversion of F-T heavy product wax to transportation fuels, and the conversion of F-T Heavy product wax to a valuable high melting point food-grade specialty wax product. Product evaluations conducted under Task 2.5 of Phase II successfully mitigated the above technical and economic risks to the EECP with the development of product yields and product qualities for the production of chemicals, transportation fuels, and specialty food-grade waxes from the F-T synthesis products.

  14. EARLY ENTRANCE COPRODUCTION PLANT

    SciTech Connect

    John Anderson; Charles Schrader

    2004-01-26

    In 1999, the U. S. Department of Energy (DOE) awarded a Cooperative Agreement to Texaco Energy Systems Inc. to provide a preliminary engineering design of an Early Entrance Coproduction Plant (EECP). Since the award, continuous and diligent work has been undertaken to achieve the design of an economical facility that makes strides toward attaining the goal of DOE's Vision 21 Program. The objective of the EECP is to convert coal and/or petroleum coke to power while coproducing transportation fuels, chemicals, and useful utilities such as steam. This objective is being pursued in a three-phase effort through the partnership of the DOE with prime contractor Texaco Energy Systems, LLC. (TES), the successor to Texaco Energy Systems, Inc. The key subcontractors to TES include General Electric (GE), Praxair, and Kellogg Brown and Root. ChevronTexaco provided gasification technology and Rentech Inc.'s Fischer-Tropsch (F-T) technology that has been developed for non-natural gas sources. GE provided gas turbine technology for the combustion of low energy content gas. Praxair provided air separation technology and KBR provided engineering to integrate the facility. A conceptual design was completed in Phase I and the report was accepted by the DOE in May 2001. The Phase I work identified risks and critical research, development, and testing that would improve the probability of technical success of the EECP. The objective of Phase II was to mitigate the risks by executing research, development, and testing. Results from the Phase II work are the subject of this report. As the work of Phase II concluded, it became evident that sufficient, but not necessarily complete, technical information and data would be available to begin Phase III - Preliminary Engineering Design. Work in Phase II requires additional technical development work to correctly apply technology at a specific site. The project's intended result is to provide the necessary technical, economic, and environmental information needed by industry to move the EECP forward to detailed design, construction, and operation. The decision to proceed with Phase III centers on locating a new site and favorable commercial and economic factors.

  15. EARLY ENTRANCE COPRODUCTION PLANT

    SciTech Connect

    David Storm; Govanon Nongbri; Steve Decanio; Ming He; Lalit Shah; Charles Schrader; Earl Berry; Peter Ricci; Belma Demirel; Charles Benham; Mark Bohn

    2004-01-12

    The overall objective of this project is the three phase development of an Early Entrance Coproduction Plant (EECP) which uses petroleum coke to produce at least one product from at least two of the following three categories: (1) electric power (or heat), (2) fuels, and (3) chemicals using ChevronTexaco's proprietary gasification technology. The objective of Phase I is to determine the feasibility and define the concept for the EECP located at a specific site; develop a Research, Development, and Testing (RD&T) Plan to mitigate technical risks and barriers; and prepare a Preliminary Project Financing Plan. The objective of Phase II is to implement the work as outlined in the Phase I RD&T Plan to enhance the development and commercial acceptance of coproduction technology. The objective of Phase III is to develop an engineering design package and a financing and testing plan for an EECP located at a specific site. The project's intended result is to provide the necessary technical, economic, and environmental information needed by industry to move the EECP forward to detailed design, construction, and operation. The partners in this project are Texaco Energy Systems LLC or TES (a subsidiary of ChevronTexaco), General Electric (GE), Praxair, and Kellogg Brown & Root (KBR) in addition to the U.S. Department of Energy (DOE). TES is providing gasification technology and Fischer-Tropsch (F-T) technology developed by Rentech, Inc., GE is providing combustion turbine technology, Praxair is providing air separation technology, and KBR is providing engineering. During Phase I, a design basis for the Fischer-Tropsch Synthesis section was developed based on limited experience with the specified feed gas and operating conditions. The objective of this Task in Phase II RD&T work was to confirm the performance of the F-T reactor at the set design conditions. Although much of the research, development, and testing work were done by TES outside of this project, several important issues were addressed in this phase of the project. They included Rejuvenation/Regeneration of the Fischer-Tropsch Catalyst, online Catalyst Withdrawal and Addition from the synthesis reactor, and the Fischer-Tropsch Design Basis Confirmation. In Phase III the results from these RD&T work will be incorporated in developing the engineering design package. This Topical Report documents the Phase II RD&T work that was completed for this task.

  16. Cold storage to overcome dormancy affects the carbohydrate status and photosynthetic capacity of Rhododendron simsii.

    PubMed

    Christiaens, A; De Keyser, E; Lootens, P; Pauwels, E; Roldán-Ruiz, I; De Riek, J; Gobin, B; Van Labeke, M-C

    2015-01-01

    Global warming leads to increasing irregular and unexpected warm spells during autumn, and therefore natural chilling requirements to break dormancy are at risk. Controlled cold treatment can provide an answer to this problem. Nevertheless, artificial cold treatment will have consequences for carbon reserves and photosynthesis. In this paper, the effect of dark cold storage at 7 °C to break flower bud dormancy in the evergreen Rhododendron simsii was quantified. Carbohydrate and starch content in leaves and flower buds of an early ('Nordlicht'), semi-early ('M. Marie') and late ('Mw. G. Kint') flowering cultivar showed that carbon loss due to respiration was lowest in 'M. Marie', while 'Mw. G. Kint' was completely depleted of starch reserves at the end of cold treatment. Gene isolation resulted in a candidate gene for sucrose synthase (SUS) RsSus, which appears to be homologous to AtSus3 and had a clear increase in expression in leaves during cold treatment. Photosynthesis measurements on 'Nordlicht' and the late-flowering cultivar 'Thesla' showed that during cold treatment, dark respiration decreased 58% and 63%, respectively. Immediately after cold treatment, dark respiration increased and stabilised after 3 days. The light compensation point followed the same trend as dark respiration. Quantum efficiency showed no significant changes during the first days after cold treatment, but was significantly higher than in plants with dormant flower buds at the start of cold treatment. In conclusion, photosynthesis stabilised 3 days after cold treatment and was improved compared to the level before cold treatment. PMID:24854016

  17. Xenopus Limb bud morphogenesis.

    PubMed

    Keenan, Samuel R; Beck, Caroline W

    2016-03-01

    Xenopus laevis, the South African clawed frog, is a well-established model organism for the study of developmental biology and regeneration due to its many advantages for both classical and molecular studies of patterning and morphogenesis. While contemporary studies of limb development tend to focus on models developed from the study of chicken and mouse embryos, there are also many classical studies of limb development in frogs. These include both fate and specification maps, that, due to their age, are perhaps not as widely known or cited as they should be. This has led to some inevitable misinterpretations- for example, it is often said that Xenopus limb buds have no apical ectodermal ridge, a morphological signalling centre located at the distal dorsal/ventral epithelial boundary and known to regulate limb bud outgrowth. These studies are valuable both from an evolutionary perspective, because amphibians diverged early from the amniote lineage, and from a developmental perspective, as amphibian limbs are capable of regeneration. Here, we describe Xenopus limb morphogenesis with reference to both classical and molecular studies, to create a clearer picture of what we know, and what is still mysterious, about this process. Developmental Dynamics 245:233-243, 2016. © 2015 Wiley Periodicals, Inc. PMID:26404044

  18. EARLY ENTRANCE COPRODUCTION PLANT

    SciTech Connect

    John Anderson; Mark Anselmo; Earl Berry; Mark Bohn; Ming He; Charles H. Schrader; Lalit Shah; Donald Todd; Robert Schavey

    2004-01-12

    The overall objective of this project is the three phase development of an Early Entrance Coproduction Plant (EECP) which uses petroleum coke to produce at least one product from at least two of the following three categories: (1) electric power (or heat), (2) fuels, and (3) chemicals using ChevronTexaco's proprietary gasification technology. The objective of Phase I is to determine the feasibility and define the concept for the EECP located at a specific site; develop a Research, Development, and Testing (RD&T) Plan to mitigate technical risks and barriers; and prepare a Preliminary Project Financing Plan. The objective of Phase II is to implement the work as outlined in the Phase I RD&T Plan to enhance the development and commercial acceptance of coproduction technology. The objective of Phase III is to develop an engineering design package and a financing and testing plan for an EECP located at a specific site. The project's intended result is to provide the necessary technical, economic, and environmental information needed by industry to move the EECP forward to its detailed design, construction, and operation. The partners in this project are Texaco Energy Systems LLC (TES) (a subsidiary of ChevronTexaco), General Electric (GE), Praxair, and Kellogg Brown & Root (KBR). The work was under cooperative agreements with the U.S. Department of Energy (DOE). TES is providing the gasification technology and the Fischer-Tropsch (F-T) technology developed by Rentech Inc., GE is providing the combustion turbine technology, Praxair is providing the air separation technology, and KBR is providing overall engineering. Each of the EECP's subsystems was assessed for technical risks and barriers in Phase I. A plan was identified to mitigate the identified risks (Phase II RD&T Plan, October 2000). The RD&T Plan identified catalyst/wax separation as a potential technical and economic risk. To mitigate risks to the proposed EECP concept, Phase II RD&T included tests for secondary catalyst/wax separation systems as part of Task 2.3--Catalyst/Wax Separation. The LCI Scepter{reg_sign} Microfiltration system was determined to be best suited for producing a filtrate that met the EECP secondary catalyst/wax separation standards of producing F-T wax containing less than10 ppmw solids. As part of task 2.3, micro-filtration removal efficiencies and production rates for two FT feeds, Rentech Inc. bubble column reactor (BCR) product and LaPorte Alternative Fuels Development Unit (AFDU) product, were evaluated. Based on comparisons between the performances of these two materials, the more readily available LaPorte AFDU material was judged an acceptable analog to the BCR material that would be produced in a larger-scale F-T synthesis. The present test was initiated to obtain data in an extended range of concentration for use in the scale-up design of the secondary catalyst/wax separation system that would be operating at the EECP capacity.

  19. EARLY ENTRANCE COPRODUCTION PLANT

    SciTech Connect

    Randy Roberts

    2003-04-25

    The overall objective of this project is the three phase development of an Early Entrance Coproduction Plant (EECP) which produces at least one product from at least two of the following three categories: (1) electric power (or heat), (2) fuels, and (3) chemicals using petroleum coke and ChevronTexaco's proprietary gasification technology. The objective of Phase I was to determine the feasibility and define the concept for the EECP located at a specific site; develop a Research, Development, and Testing (RD&T) Plan to mitigate technical risks and barriers; and prepare a Preliminary Project Financing Plan. The objective of Phase II is to implement the work as outlined in the Phase I RD&T Plan to enhance the development and commercial acceptance of coproduction technology. The objective of Phase III is to develop an engineering design package and a financing and testing plan for an EECP located at a specific site. The project's intended result is to provide the necessary technical, economic, and environmental information needed by industry to move the EECP forward to detailed design, construction, and operation. The partners in this project are Texaco Energy Systems LLC. (a subsidiary of ChevronTexaco), General Electric (GE), Praxair, and Kellogg Brown & Root (KBR) in addition to the U.S. Department of Energy (DOE). ChevronTexaco is providing gasification technology and Fischer-Tropsch technology developed by Rentech, GE is providing combustion turbine technology, Praxair is providing air separation technology and KBR is providing engineering. Each of the EECP subsystems were assessed for technical risks and barriers. A plan was identified to mitigate the identified risks (Phase II RD&T Plan, October 2000). The RD&T Plan identified F-T reactor scale-up as a potential technical risk. The objective of Task 2.3 was to confirm engineering models that allow scale-up to commercial slurry phase bubble column (SPBC) reactors operating in the churn-turbulent flow regime. In developmental work outside the scope of this project, historical data, literature references, and a scale-up from a 1 1/2-in. (3.8 cm) to 6-ft (1.8 m) SPBC reactor have been reviewed. This review formed the background for developing scale-up models for a SPBC reactor operating in the churn-turbulent flow regime. The necessary fundamental physical parameters have been measured and incorporated into the mathematical catalyst/kinetic model developed from the SPBC and CSTR work outside the scope of this EECP project. The mathematical catalyst/kinetic model was used to compare to experimental data obtained at Rentech during the EECP Fischer-Tropsch Confirmation Run (Task 2.1; reported separately). The prediction of carbon monoxide (CO) conversion as a function of days on stream compares quite closely to the experimental data.

  20. EARLY ENTRANCE COPRODUCTION PLANT

    SciTech Connect

    Charles Benham; Mark Bohn; John Anderson; Earl Berry; Fred Brent; Ming He; Randy Roberts; Lalit Shah; Marjan Roos

    2003-09-15

    The 1999 U. S. Department of Energy (DOE) award to Texaco Energy Systems Inc. (presently Texaco Energy Systems LLC, a subsidiary of ChevronTexaco) was made to provide a Preliminary Engineering Design of an Early Entrance Coproduction Plant (EECP). Since the award presentation, work has been undertaken to achieve an economical concept design that makes strides toward the DOE Vision 21 goal. The objective of the EECP is to convert coal and/or petroleum coke to electric power plus transportation fuels, chemicals and useful utilities such as steam. The use of petroleum coke was added as a fuel to reduce the cost of feedstock and also to increase the probability of commercial implementation of the EECP concept. This objective has been pursued in a three phase effort through the partnership of the DOE with prime contractor Texaco Energy Systems LLC and subcontractors General Electric (GE), Praxair, and Kellogg Brown and Root (KBR). ChevronTexaco is providing gasification technology and Rentech's Fischer-Tropsch technology that has been developed for non-natural gas feed sources. GE is providing gas turbine technology for the combustion of low energy content gas. Praxair is providing air separation technology, and KBR is providing engineering to integrate the facility. The objective of Phase I was to determine the feasibility and define the concept for the EECP located at a specific site; develop a Research, Development, and Testing (RD&T) Plan to mitigate technical risks and barriers; and prepare a Preliminary Project Financing Plan. The objective of Phase II is to implement the work as outlined in the Phase I RD&T Plan to enhance the development and commercial acceptance of coproduction technology. The objective of Phase III is to develop an engineering design package and a financing and testing plan for an EECP located at a specific site. Phase I Preliminary Concept Report was completed in 2000. The Phase I Preliminary Concept Report was prepared based on making assumptions for the basis of design for various technologies that are part of the EECP concept. The Phase I Preliminary Concept Report was approved by the DOE in May 2001. The Phase I work identified technical and economic risks and critical research, development, and testing that would improve the probability of the technical and economic success of the EECP. The Project Management Plan (Task 1) for Phase II was approved by the DOE in 2001. The results of RD&T efforts for Phase II are expected to improve the quality of assumptions made in Phase I for basis of design for the EECP concept. The RD&T work plan (Task 2 and 3) for Phase II has been completed. As the RD&T work conducted during Phase II concluded, it became evident that sufficient, but not necessarily complete, technical information and data would be available to begin Phase III - Basic Engineering Design. Also due to the merger of Chevron and Texaco, the proposed refinery site for the EECP was not available. It became apparent that some additional technical development work would be needed to correctly apply the technology at a specific site. The objective of Task 4 of Phase II is to update the concept basis of design produced during Phase I. As part of this task, items that will require design basis changes and are not site dependent have been identified. The team has qualitatively identified the efforts to incorporate the impacts of changes on EECP concept. The design basis has been modified to incorporate those changes. The design basis changes for those components of EECP that are site and feedstock dependent will be done as part of Phase III, once the site has been selected.

  1. EARLY ENTRANCE COPRODUCTION PLANT

    SciTech Connect

    John H. Anderson; Charles Benham; Earl R. Berry; Ming He; Charles H. Schrader; Lalit S. Shah; O.O. Omatete; T.D. Burchell

    2004-01-12

    The overall objective of this project is the three phase development of an Early Entrance Coproduction Plant (EECP) which uses petroleum coke to produce at least one product from at least two of the following three categories: (1) electric power (or heat), (2) fuels, and (3) chemicals using ChevronTexaco's proprietary gasification technology. The objective of Phase I is to determine the feasibility and define the concept for the EECP located at a specific site; develop a Research, Development, and Testing (RD&T) Plan to mitigate technical risks and barriers; and prepare a Preliminary Project Financing Plan. The objective of Phase II is to implement the work as outlined in the Phase I RD&T Plan to enhance the development and commercial acceptance of coproduction technology. The objective of Phase III is to develop an engineering design package and a financing and testing plan for an EECP located at a specific site. The project's intended result is to provide the necessary technical, economic, and environmental information needed by industry to move the EECP forward to detailed design, construction, and operation. The partners in this project are Texaco Energy Systems LLC or TES (a subsidiary of ChevronTexaco), General Electric (GE), Praxair, and Kellogg Brown & Root (KBR) in addition to the U.S. Department of Energy (DOE). TES is providing gasification technology and Fischer-Tropsch (F-T) technology developed by Rentech, GE is providing combustion turbine technology, Praxair is providing air separation technology, and KBR is providing engineering. During Phase I the team identified several potential methods to reduce or minimize the environmental impact of the proposed EECP. The EECP Project Team identified F-T catalyst disposal, beneficial gasifier slag usage (other than landfill), and carbon dioxide recovery for the gas turbine exhaust for study under this task. Successfully completing the Task 2.10 RD&T provides additional opportunities for the EECP to meet the goals of DOE's Vision 21 Program. The gasification section offers several opportunities to maximize the environmental benefits of an EECP. The spent F-T catalyst can be sent to landfills or to the gasification section. Testing in Phase II shows that the spent F-T catalyst with a small wax coating can safely meet federal landfill requirements. As an alternative to landfilling, it has been proposed to mix the spent F-T catalyst with the petroleum coke and feed this mixture to the gasification unit. Based on ChevronTexaco's experience with gasification and the characteristics of the spent F-T catalyst this appears to be an excellent opportunity to reduce one potential waste stream. The slag from the gasification unit can be commercially marketed for construction or fuel (such as cement kiln fuel) uses. The technical and economic benefits of these options must be reviewed for the final EECP before incorporating a specific alternative into the design basis. Reducing greenhouse gas emissions, particularly carbon dioxide, is an important goal of the EECP. The Texaco gasification process provides opportunities to capture high purity streams of carbon dioxide. For Phase II, a carbon fiber composite molecular sieve (CFCMS) was tested to determine its potential to remove high purity carbon dioxide from the exhaust of a gas turbine. Testing on with a simulated gas turbine exhaust shows that the CFCMS is able to remove high purity carbon dioxide from the exhaust. However, more development is required to optimize the system.

  2. EARLY ENTRANCE COPRODUCTION PLANT

    SciTech Connect

    John Anderson; Mark Anselmo; Earl Berry; Mark Bohn; Roko Bujas; Ming He; Ken Kwik; Charles H. Schrader; Lalit Shah; Dennis Slater; Donald Todd; Don Wall

    2003-08-21

    The overall objective of this project is the three phase development of an Early Entrance Coproduction Plant (EECP) which uses petroleum coke to produce at least one product from at least two of the following three categories: (1) electric power (or heat), (2) fuels, and (3) chemicals using ChevronTexaco's proprietary gasification technology. The objective of Phase I is to determine the feasibility and define the concept for the EECP located at a specific site; develop a Research, Development, and Testing (RD&T) Plan to mitigate technical risks and barriers; and prepare a Preliminary Project Financing Plan. The objective of Phase II is to implement the work as outlined in the Phase I RD&T Plan to enhance the development and commercial acceptance of coproduction technology. The objective of Phase III is to develop an engineering design package and a financing and testing plan for an EECP located at a specific site. The project's intended result is to provide the necessary technical, economic, and environmental information needed by industry to move the EECP forward to detailed design, construction, and operation. The partners in this project are Texaco Energy Systems LLC (TES), a subsidiary of ChevronTexaco, General Electric (GE), Praxair, and Kellogg Brown & Root (KBR) in addition to the U.S. Department of Energy (DOE). TES is providing gasification technology and Fischer-Tropsch (F-T) technology developed by Rentech, Inc. GE is providing combustion turbine technology, Praxair is providing air separation technology, and KBR is providing engineering. Each of the EECP subsystems were assessed for technical risks and barriers. A plan was identified to mitigate the identified risks (Phase II RD&T Plan, October 2000). The RD&T Plan identified catalyst/wax separation as a potential technical and economic risk. To mitigate risks to the proposed EECP, Phase II RD&T included tests of an alternative (to Rentech's Dynamic Settler) primary catalyst/wax separation device and secondary catalyst/wax separation systems. The team evaluated multiple technologies for both primary and secondary catalyst/wax separation. Based on successful testing at Rentech (outside of DOE funding) and difficulties in finalizing a contract to demonstrate alternative primary catalyst/wax separation technology (using magnetic separation technology), ChevronTexaco has selected the Rentech Dynamic Settler for primary catalyst/wax separation. Testing has shown the Dynamic Settler is capable of producing filtrate exceeding the proposed EECP primary catalyst/wax separation goal of less than 0.1 wt%. The LCI Scepter{reg_sign} Microfiltration system appeared to be best suited for producing a filtrate that met the EECP secondary catalyst/wax separation standards of 10 parts per million (weight) [ppmw]. The other technologies, magnetic separation and electrostatic separation, were promising and able to reduce the solids concentrations in the filtrate. Additional RD&T will be needed for magnetic separation and electrostatic separation technologies to obtain 10 ppmw filtrate required for the proposed EECP. The Phase II testing reduces the technical and economic risks and provides the information necessary to proceed with the development of an engineering design for the EECP Fischer-Tropsch catalyst/wax separation system.

  3. EARLY ENTRANCE COPRODUCTION PLANT

    SciTech Connect

    Abdalla H. Ali; Raj Kamarthi; John H. Anderson; Earl R. Berry; Charles H. Schrader; Lalit S. Shah

    2003-04-16

    The overall objective of this project is the three phase development of an Early Entrance Coproduction Plant (EECP) which produces at least one product from at least two of the following three categories: (1) electric power (or heat), (2) fuels, and (3) chemicals using ChevronTexaco's proprietary gasification technology. The objective of Phase I is to determine the feasibility and define the concept for the EECP located at a specific site; develop a Research, Development, and Testing (RD&T) Plan to mitigate technical risks and barriers; and prepare a Preliminary Project Financing Plan. The objective of Phase II is to implement the work as outlined in the Phase I RD&T Plan to enhance the development and commercial acceptance of coproduction technology. The objective of Phase III is to develop an engineering design package and a financing and testing plan for an EECP located at a specific site. The project's intended result is to provide the necessary technical, economic, and environmental information needed by industry to move the EECP forward to detailed design, construction, and operation. The partners in this project are TES (a subsidiary of ChevronTexaco), General Electric (GE), Praxair, and Kellogg Brown & Root (KBR) in addition to the U.S. Department of Energy (DOE). TES is providing gasification technology and Fischer-Tropsch (F-T) technology developed by Rentech, GE is providing combustion turbine technology, Praxair is providing air separation technology, and KBR is providing engineering. During Phase I the team identified the integration of the water produced in the F-T synthesis section with the gasification section as an area of potential synergy. By utilizing the F-T water in the petroleum coke slurry for the gasifier, the EECP can eliminate a potential waste stream and reduce capital costs. There is a low technical risk for this synergy, however, the economic risk, particularly in regards to the water, can be high. The economic costs include the costs of treating the water to meet the locally applicable environmental standards. This option may require expensive chemicals and treatment facilities. EECP Phase II included tests conducted to confirm the viability of integrating F-T water in the slurry feed for the gasifier. Testing conducted at ChevronTexaco's Montebello Technology Center (MTC) included preparing slurries made using petroleum coke with F-T water collected at the LaPorte Alternative Fuels Development Unit (AFDU). The work included bench scale tests to determine the slurry ability of the petroleum coke and F-T water. The results of the tests show that F-T water does not adversely affect slurries for the gasifier. There are a few cases where in fact the addition of F-T water caused favorable changes in viscosity of the slurries. This RD&T task was executed in Phase II and results are reported herein.

  4. Potato tuber dormancy and postharvest sprout control

    Technology Transfer Automated Retrieval System (TEKTRAN)

    For an indeterminate period of time following harvest, potatoes will not sprout and are physiologically dormant. Dormancy is gradually lost during postharvest storage and the resultant sprouting is detrimental to the nutritional and processing qualities of potatoes. Because of this, sprouting resu...

  5. Budding and fission of vesicles.

    PubMed

    Döbereiner, H G; Käs, J; Noppl, D; Sprenger, I; Sackmann, E

    1993-10-01

    We report on budding and fission of protein-free vesicles swollen from a natural lipid mixture of bovine brain sphingomyelins. Budding was induced by increasing the area-to-volume ratio through heating. Morphological changes were monitored by phase contrast microscopy and correlated with the thermal behavior of the bilayer by differential scanning calorimetry. Freeze fracture electron microscopy revealed that budding and fission are not restricted to giant vesicles but also occur on length scales relevant for cellular processes. We also observed osmotically induced budding and fission in mixtures of dimyristoyl phosphatidylcholine with cholesterol. We find that these shape transitions are driven by liquid/gel domain formation and/or coupling of the spontaneous curvature of the membrane to the local lipid composition. Our results provide evidence that coat proteins are not necessary for budding and fission of vesicles. The physics of the lipid bilayer is rich enough to explain the observed behavior. PMID:8274633

  6. Rabies virus assembly and budding.

    PubMed

    Okumura, Atsushi; Harty, Ronald N

    2011-01-01

    Rabies virus (RABV) and other negative-strand RNA viruses are the causes of serious diseases in humans and animals worldwide. Assembly and budding are important late events in the replication cycles of these negative-strand RNA viruses that have received much attention in the past decade. Indeed, important insights into the molecular mechanisms by which rhabdoviral proteins usurp and/or interact with host proteins to promote efficient virion assembly and egress has greatly enhanced our understanding of the budding process. Assembly/budding of rhabdoviruses is driven largely by the matrix (M) protein. RABV M protein contains a late budding domain that mediates the recruitment of host proteins linked to the vacuolar protein sorting pathway of the cell to facilitate virus-cell separation. This chapter summarizes our current knowledge of the roles that both RABV M protein and interacting host proteins play during the budding process. PMID:21601040

  7. EARLY ENTRANCE COPRODUCTION PLANT

    SciTech Connect

    Fred D. Brent; Lalit Shah; Earl Berry; Charles H. Schrader; John Anderson; J. Erwin; Matthew G. Banks; Terry L. Ullman

    2004-01-12

    The overall objective of this project is the three phase development of an Early Entrance Coproduction Plant (EECP) which uses petroleum coke to produce at least one product from at least two of the following three categories: (1) electric power (or heat), (2) fuels, and (3) chemicals using ChevronTexaco's proprietary gasification technology. The objective of Phase I is to determine the feasibility and define the concept for the EECP located at a specific site; develop a Research, Development, and Testing (RD&T) Plan to mitigate technical risks and barriers; and prepare a Preliminary Project Financing Plan. The objective of Phase II is to implement the work as outlined in the Phase I RD&T Plan to enhance the development and commercial acceptance of coproduction technology. The objective of Phase III is to develop an engineering design package and a financing and testing plan for an EECP located at a specific site. The project's intended result is to provide the necessary technical, economic, and environmental information needed by industry to move the EECP forward to detailed design, construction, and operation. The partners in this project are Texaco Energy Systems LLC or TES (a subsidiary of ChevronTexaco), General Electric (GE), Praxair, and Kellogg Brown & Root (KBR) in addition to the U.S. Department of Energy (DOE). TES is providing gasification technology and Fischer-Tropsch (F-T) technology developed by Rentech, GE is providing combustion turbine technology, Praxair is providing air separation technology, and KBR is providing engineering. Each of the EECP subsystems was assessed for technical risks and barriers. A plan was developed to mitigate the identified risks (Phase II RD&T Plan, October 2000). Phase II RD&T Task 2.6 identified as potential technical risks to the EECP the fuel/engine performance and emissions of the F-T diesel fuel products. Hydrotreating the neat F-T diesel product reduces potentially reactive olefins, oxygenates, and acids levels and alleviates corrosion and fuel stability concerns. Future coproduction plants can maximize valuable transportation diesel by hydrocracking the F-T Synthesis wax product to diesel and naphtha. The upgraded neat F-T diesel, hydrotreater F-T diesel, and hydrocracker F-T diesel products would be final blending components in transportation diesel fuel. Phase II RD&T Task 2.6 successfully carried out fuel lubricity property testing, fuel response to lubricity additives, and hot-start transient emission tests on a neat F-T diesel product, a hydrocracker F-T diesel product, a blend of hydrotreater and hydrocracker F-T diesel products, and a Tier II California Air Resources Board (CARB)-like diesel reference fuel. Only the neat F-T diesel passed lubricity inspection without additive while the remaining three fuel candidates passed with conventional additive treatment. Hot-start transient emission tests were conducted on the four fuels in accordance with the U.S. Environmental Protection Agency (EPA) Federal Test Procedure (FTP) specified in Code of Federal Regulations, Title 40, Part 86, and Subpart N on a rebuilt 1991 Detroit Diesel Corporation Series 60 heavy-duty diesel engine. Neat F-T diesel fuel reduced oxides of nitrogen (NO{sub x}), total particulate (PM), hydrocarbons (HC), carbon monoxide (CO), and the Soluble Organic Fraction (SOF) by 4.5%, 31%, 50%, 29%, and 35%, respectively, compared to the Tier II CARB-like diesel. The hydrocracker F-T diesel product and a blend of hydrocracker and hydrotreater F-T diesel products also reduced NO{sub x}, PM, HC, CO and SOF by 13%, 16% to 17%, 38% to 63%, 17% to 21% and 21% to 39% compared to the Tier II CARB-like diesel. The fuel/engine performance and emissions of the three F-T diesel fuels exceed the performance of a Tier II CARB-like diesel. Phase II RD&T Task 2.6 successfully met the lubricity property testing and F-T diesel fuel hot-start transient emissions test objectives. The results of the testing help mitigate potential economic risks on obtaining a premium price for the F-T diesel fuel in the marketplace. The F-T diesel fuel superior properties of low sulfur, low aromatics, and high cetane resulted in lower emissions yields if compared to conventional diesel fuels.

  8. EARLY ENTRANCE COPRODUCTION PLANT

    SciTech Connect

    Abdalla H. Ali; John H. Anderson; Earl R. Berry; Charles H. Schrader; Lalit S. Shah

    2003-04-16

    The overall objective of this project is the three phase development of an Early Entrance Coproduction Plant (EECP) which produces at least one product from at least two of the following three categories: (1) electric power (or heat), (2) fuels, and (3) chemicals using ChevronTexaco's proprietary gasification technology. The objective of Phase I is to determine the feasibility and define the concept for the EECP located at a specific site; develop a Research, Development, and Testing (RD&T) Plan to mitigate technical risks and barriers; and prepare a Preliminary Project Financing Plan. The objective of Phase II is to implement the work as outlined in the Phase I RD&T Plan to enhance the development and commercial acceptance of coproduction technology. The objective of Phase III is to develop an engineering design package and a financing and testing plan for an EECP located at a specific site. The project's intended result is to provide the necessary technical, economic, and environmental information needed by industry to move the EECP forward to detailed design, construction, and operation. The partners in this project are TES (a subsidiary of ChevronTexaco), General Electric (GE), Praxair, and Kellogg Brown & Root (KBR) in addition to the U.S. Department of Energy (DOE). TES is providing gasification technology and Fischer-Tropsch (F-T) technology developed by Rentech, GE is providing combustion turbine technology, Praxair is providing air separation technology, and KBR is providing engineering. Each of the EECP subsystems were assessed for technical risks and barriers. A plan was identified to mitigate the identified risks (Phase II RD&T Plan, October 2000). The RD&T Plan identified petroleum coke characteristics as a potential technical risk. The composition of petroleum coke varies from one refinery to another. Petroleum coke characteristics are a function of the crude oil slate available at the refinery and the coker operating parameters. The specific petroleum coke characteristics at a refinery affect the design of the Gasification and Acid Gas Removal (AGR) subsystems. Knowing the petroleum coke composition provides the necessary data to proceed to the EECP Phase III engineering design of the gasification process. Based on ChevronTexaco's experience, the EECP team ranked the technical, economic, and overall risks of the petroleum coke composition related to the gasification subsystem as low. In Phase I of the EECP Project, the Motiva Port Arthur Refinery had been identified as the potential EECP site. As a result of the merger between Texaco and Chevron in October 2001, Texaco was required to sell its interest in the Motiva Enterprises LLC joint venture to Shell Oil Company and Saudi Refining Inc. To assess the possible impact of moving the proposed EECP host site to a ChevronTexaco refinery, samples of petroleum coke from two ChevronTexaco refineries were sent to MTC for bench-scale testing. The results of the analysis of these samples were compared to the Phase I EECP Gasification Design Basis developed for Motiva's Port Arthur Refinery. The analysis confirms that if the proposed EECP is moved to a new refinery site, the Phase I EECP Gasification Design Basis would have to be updated. The lower sulfur content of the two samples from the ChevronTexaco refineries indicates that if one of these sites were selected, the Sulfur Recovery Unit (SRU) might be sized smaller than the current EECP design. This would reduce the capital expense of the SRU. Additionally, both ChevronTexaco samples have a higher hydrogen to carbon monoxide ratio than the Motiva Port Arthur petroleum coke. The higher hydrogen to carbon monoxide ratio could give a slightly higher F-T products yield from the F-T Synthesis Reactor. However, the EECP Gasification Design Basis can not be updated until the site for the proposed EECP site is finalized. Until the site is finalized, the feedstock (petroleum coke) characteristics are a low risk to the EECP project.

  9. Differential dormancy of co-occurring copepods

    NASA Astrophysics Data System (ADS)

    Ohman, Mark D.; Drits, Aleksandr V.; Elizabeth Clarke, M.; Plourde, Stéphane

    1998-08-01

    Four species of planktonic calanoid copepods that co-occur in the California Current System ( Eucalanus californicus Johnson, Rhincalanus nasutus Giesbrecht, Calanus pacificus californicus Brodsky, and Metridia pacifica Brodsky) were investigated for evidence of seasonal dormancy in the San Diego Trough. Indices used to differentiate actively growing from dormant animals included developmental stage structure and vertical distribution; activity of aerobic metabolic enzymes (Citrate Synthase and the Electron Transfer System complex); investment in depot lipids (wax esters and triacylglycerols); in situ grazing activity from gut fluorescence; and egg production rates in simulated in situ conditions. None of the 4 species exhibited a canonical calanoid pattern of winter dormancy - i.e., synchronous developmental arrest as copepodid stage V, descent into deep waters, reduced metabolism, and lack of winter reproduction. Instead, Calanus pacificus californicus has a biphasic life history in this region, with an actively reproducing segment of the population in surface waters overlying a deep dormant segment in winter. Eucalanus californicus is dormant as both adult females and copepodid V's, although winter females respond relatively rapidly to elevated food and temperature conditions; they begin feeding and producing eggs within 2-3 days. Rhincalanus nasutus appears to enter dormancy as adult females, although the evidence is equivocal. Metridia pacifica shows no evidence of dormancy, with sustained active feeding, diel vertical migration behavior, and elevated activity of metabolic enzymes in December as well as in June. The four species also differ markedly in water content, classes of storage lipids, and specific activity of Citrate Synthase. These results suggest that copepod dormancy traits and structural composition reflect diverse adaptations to regional environmental conditions rather than a uniform, canonical series of traits that remain invariant among taxa and fixed across a species' range. Such interspecific and regional differences in life history traits need to be incorporated in models simulating Eastern Boundary Current pelagic ecosystem dynamics.

  10. Transcriptome Profiling of Tiller Buds Provides New Insights into PhyB Regulation of Tillering and Indeterminate Growth in Sorghum.

    PubMed

    Kebrom, Tesfamichael H; Mullet, John E

    2016-04-01

    Phytochrome B (phyB) enables plants to modify shoot branching or tillering in response to varying light intensities and ratios of red and far-red light caused by shading and neighbor proximity. Tillering is inhibited in sorghum genotypes that lack phytochrome B (58M, phyB-1) until after floral initiation. The growth of tiller buds in the first leaf axil of wild-type (100M, PHYB) and phyB-1 sorghum genotypes is similar until 6 d after planting when buds of phyB-1 arrest growth, while wild-type buds continue growing and develop into tillers. Transcriptome analysis at this early stage of bud development identified numerous genes that were up to 50-fold differentially expressed in wild-type/phyB-1 buds. Up-regulation of terminal flower1, GA2oxidase, and TPPI could protect axillary meristems in phyB-1 from precocious floral induction and decrease bud sensitivity to sugar signals. After bud growth arrest in phyB-1, expression of dormancy-associated genes such as DRM1, GT1, AF1, and CKX1 increased and ENOD93, ACCoxidase, ARR3/6/9, CGA1, and SHY2 decreased. Continued bud outgrowth in wild-type was correlated with increased expression of genes encoding a SWEET transporter and cell wall invertases. The SWEET transporter may facilitate Suc unloading from the phloem to the apoplast where cell wall invertases generate monosaccharides for uptake and utilization to sustain bud outgrowth. Elevated expression of these genes was correlated with higher levels of cytokinin/sugar signaling in growing buds of wild-type plants. PMID:26893475

  11. Influenza Virus Assembly and Budding

    PubMed Central

    Rossman, Jeremy S.; Lamb, Robert A.

    2011-01-01

    Influenza A virus causes seasonal epidemics, sporadic pandemics and is a significant global heath burden. Influenza virus is an enveloped virus that contains a segmented negative strand RNA genome. Assembly and budding of progeny influenza virions is a complex, multistep process that occurs in lipid raft domains on the apical membrane of infected cells. The viral proteins hemagglutinin (HA) and neuraminidase (NA) are targeted to lipid rafts, causing the coalescence and enlargement of the raft domains. This clustering of HA and NA may cause a deformation of the membrane and the initiation of the virus budding event. M1 is then thought to bind to the cytoplasmic tails of HA and NA where it can then polymerize and form the interior structure of the emerging virion. M1, bound to the cytoplasmic tails of HA and NA, additionally serves as a docking site for the recruitment of the viral RNPs and may mediate the recruitment of M2 to the site of virus budding. M2 initially stabilizes the site of budding, possibly enabling the polymerization of the matrix protein and the formation of filamentous virions. Subsequently, M2 is able to alter membrane curvature at the neck of the budding virus, causing membrane scission and the release of the progeny virion. This review investigates the latest research on influenza virus budding in an attempt to provide a step-by-step analysis of the assembly and budding processes for influenza viruses. PMID:21237476

  12. Development of flower buds in the Japanese pear (Pyrus pyrifolia) from late autumn to early spring.

    PubMed

    Saito, Takanori; Tuan, Pham Anh; Katsumi-Horigane, Akemi; Bai, Songling; Ito, Akiko; Sekiyama, Yasuyo; Ono, Hiroshi; Moriguchi, Takaya

    2015-06-01

    We periodically investigated the lateral flower bud morphology of 1-year shoots of 'Kosui' pears (Pyrus pyrifolia Nakai) in terms of dormancy progression, using magnetic resonance imaging. The size of flower buds did not change significantly during endodormancy, but rapid enlargement took place at the end of the ecodormancy stage. To gain insight into the physiological status during this period, we analyzed gene expression related to cell cycle-, cell expansion- and water channel-related genes, namely cyclin (CYC), expansin (EXPA), tonoplast intrinsic proteins (TIP) and plasma membrane intrinsic proteins (PIP). Constant but low expression of pear cyclin genes (PpCYCD3s) was observed in the transition phase from endodormancy to ecodormancy. The expression levels of PpCYCD3s were consistent with few changes in flower bud size, but up-regulated before the sprouting stage. In contrast, the expression of pear expansin and water channel-related genes (PpEXPA2, PpPIP2A, PpPIP2B, PpIδTIP1A and PpIδTIP1B) were low until onset of the rapid enlargement stage of flower buds. However, expression of these genes rapidly increased during sprouting along with a gradual increase of free water content in the floral primordia of buds. Taken together, these results suggest that flower bud size tends to stay constant until the endodormancy phase transition. Rapid enlargement of flower buds observed in March is partly due to the enhancement of the cell cycle. Then, sprouting takes place concomitant with the increase in cell expansion and free water movement. PMID:26063707

  13. MICROARRAY ANALYSIS IDENTIFIES GENES INVOLVED IN CROWN BUD DORMANCY IN LEAFY SPURGE (EUPHORBIA ESULA L.)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Leafy spurge is a perennial rangeland weed that has become a model for weed genomics and cross-species research. Microarray analysis allows the simultaneous characterization of the expression from thousands of different genes from any given sampled tissue. We have used microarray analysis to follow ...

  14. LEAFY SPURGE: DEVELOPMENT AND USE OF A MODEL PLANT FOR GENOMIC ANALYSIS OF BUD DORMANCY

    Technology Transfer Automated Retrieval System (TEKTRAN)

    One of the greatest advances in plant science has been the designation and study of model plants. Although model systems have benefited the weed science community by providing a greater understanding of plant physiology and genetics, the scientific gains have often precluded the analysis of traits t...

  15. A molecular marker associated with low-temperature induction of dormancy in red osier dogwood (Cornus sericea).

    PubMed

    Svendsen, Erl; Wilen, Ron; Stevenson, Robert; Liu, Rensong; Tanino, Karen K

    2007-03-01

    Dormancy induction in temperate deciduous plants is thought to be regulated by short photoperiods, but low temperature has been shown to eliminate the short photoperiod requirement in northern ecotypes. An F2 population (191 plants) red osier dogwood (Cornus sericea L.) derived from a polycross of an F1 population produced from reciprocal crosses of the parental clonal ecotypes, Northwest Territories (NWT, 62 degrees N) and Utah (42 degrees N), was examined to identify molecular markers of temperature-induced endodormancy. Dormancy induction curves were generated for each individual in the F2 population and a standard point prior to vegetative maturity (i-VM) was inferred from the change in slope of the dormancy acquisition curve. Under Saskatoon, Saskatchewan field conditions (52 degrees N), the NWT ecotype entered i-VM on average 5-6 weeks before the Utah ecotype. Two sub-populations of the F2 population were distinguishable based on VM acquisition on exposure to low temperature but not to short photoperiods. A sequence characterized amplified region (SCAR) marker was developed that correctly (> 92%) identified individual plants within the F2 subpopulation that were responsive to low-temperature induction of VM. Timing of bud break was strongly associated with the timing of VM in the geographical ecotypes but not in the F2 population, indicating that these are separate traits under genetic control. PMID:17241980

  16. Long and short photoperiod buds in hybrid aspen share structural development and expression patterns of marker genes

    PubMed Central

    Rinne, Päivi L.H.; Paul, Laju K.; Vahala, Jorma; Ruonala, Raili; Kangasjärvi, Jaakko; van der Schoot, Christiaan

    2015-01-01

    Tree architecture develops over time through the collective activity of apical and axillary meristems. Although the capacity of both meristems to form buds is crucial for perennial life, a comparative analysis is lacking. As shown here for hybrid aspen, axillary meristems engage in an elaborate process of axillary bud (AXB) formation, while apical dominance prevents outgrowth of branches. Development ceased when AXBs had formed an embryonic shoot (ES) with a predictable number of embryonic leaves at the bud maturation point (BMP). Under short days, terminal buds (TBs) formed an ES similar to that of AXBs, and both the TB and young AXBs above the BMP established dormancy. Quantitative PCR and in situ hybridizations showed that this shared ability and structural similarity was reflected at the molecular level. TBs and AXBs similarly regulated expression of meristem-specific and bud/branching-related genes, including CENTRORADIALIS-LIKE1 (CENL1), BRANCHED1 (BRC1), BRC2, and the strigolactone biosynthesis gene MORE AXILLARY BRANCHES1 (MAX1). Below the BMP, AXBs maintained high CENL1 expression at the rib meristem, suggesting that it serves to maintain poise for growth. In support of this, decapitation initiated outgrowth of CENL1-expressing AXBs, but not of dormant AXBs that had switched CENL1 off. This singles out CENL1 as a rib meristem marker for para-dormancy. BRC1 and MAX1 genes, which may counterbalance CENL1, were down-regulated in decapitation-activated AXBs. The results showed that removal of apical dominance shifted AXB gene expression toward that of apices, while developing TBs adopted the expression pattern of para-dormant AXBs. Bud development thus follows a shared developmental pattern at terminal and axillary positions, despite being triggered by short days and apical dominance, respectively. PMID:26248666

  17. [Effects of low temperature on dormancy breaking and growth after planting in bulbs of Tulipa edulis].

    PubMed

    Yang, Ying; Zhu, Zai-Biao; Guo, Qiao-Sheng; Miao, Yuan-Yuan; Ma, Hong-Liang; Yang, Xiao-Hua

    2015-01-01

    The effect of low temperature storage on dormancy breaking, sprouting and growth after planting of Tulipa edulis was studied. The results showed that starch content and activity of amylases significantly decreased during 10 weeks of cold storage, soluble protein content raised at first then decreased, and the peak appeared at the 6th week. However, total soluble sugar content which in- creased slowly at first than rose sharply and reducing sugar content increased during the storage duration. The bulbs with cold storage treatment rooted in the 6th week, which was about 2 weeks earlier than room temperature storage, but there were less new roots in the late period of storage. After stored at a low temperature, bud lengths were longer than that with room temperature treatment. Cold storage treatment could promote earlier emergence, shorten germination time, prolong growth period and improve the yield of bulb, but rarely affect the emergence rate. It was not beneficial to flowering and fruiting. The results indicated that 6-8 weeks of cold storage was deemed to be the key period of dormancy breaking preliminary. PMID:25993786

  18. Tube entrance lens focus control

    NASA Astrophysics Data System (ADS)

    Weisser, D. C.; Fifield, L. K.; Kitchen, T. F. G.; Tunningley, T. B.; Lobanov, N. R.; Muirhead, A. G.

    2013-02-01

    The entrance of the accelerator tube in a large electrostatic accelerator imposes a strong lens that dominates the beam optics. The magnification of the lens is large because of the low injection energy, the high voltage gradient of the acceleration tube and the long distance to the terminal. In the absence of the acceleration, the magnification would produce an unacceptably large beam spot at the terminal. The tyranny of the lens is especially irksome when the accelerator is required to operate at a lower terminal voltage than the one corresponding to the nominal gradient at high voltage. One way around the difficulty, used in NEC Pelletron accelerators, is to insert a series of nylon and steel rods that short together units of the acceleration structure at the terminal leaving the ones near the entrance close to the nominal gradient for optimum transmission. This operation takes time and risks the loss of insulating gas. Another alternative used in the 25URC at Oak Ridge National Laboratory, is to focus the beam at the tube entrance, substantially diluting the effect of the entrance lens. The beam then diverges and so requires an additional lens part way to the terminal. This solution is only partially effective and still necessitates use of shorting rods for low voltage operation. The fact that these elaborate strategies are used is evidence that the alternative of lowering the injection energy as the terminal voltage is lowered imposes enough problems that it is not used in practice. We have modeled a solution that controls the voltage gradient at the tube entrance using an external power supply. This not only maintains the focusing effect of the lens but provides the opportunity to tune the beam by adjusting the entrance lens. A 150 kV power supply outside the pressure vessel feeds a controllable voltage through a high voltage feed-through to the fifth electrode of the accelerator tube. Thus 150 kV on this electrode creates the nominal gradient of 30 kV per gap. The beam optics simulations demonstrating the effectiveness of this will be presented along with the design of the tested high voltage feed through.

  19. Winter warming delays dormancy release, advances budburst, alters carbohydrate metabolism and reduces yield in a temperate shrub

    PubMed Central

    Pagter, Majken; Andersen, Uffe Brandt; Andersen, Lillie

    2015-01-01

    Global climate models predict an increase in the mean surface air temperature, with a disproportionate increase during winter. Since temperature is a major driver of phenological events in temperate woody perennials, warming is likely to induce changes in a range of these events. We investigated the impact of slightly elevated temperatures (+0.76 °C in the air, +1.35 °C in the soil) during the non-growing season (October–April) on freezing tolerance, carbohydrate metabolism, dormancy release, spring phenology and reproductive output in two blackcurrant (Ribes nigrum) cultivars to understand how winter warming modifies phenological traits in a woody perennial known to have a large chilling requirement and to be sensitive to spring frost. Warming delayed dormancy release more in the cultivar ‘Narve Viking’ than in the cultivar ‘Titania’, but advanced budburst and flowering predominantly in ‘Titania’. Since ‘Narve Viking’ has a higher chilling requirement than ‘Titania’, this indicates that, in high-chilling-requiring genotypes, dormancy responses may temper the effect of warming on spring phenology. Winter warming significantly reduced fruit yield the following summer in both cultivars, corroborating the hypothesis that a decline in winter chill may decrease reproductive effort in blackcurrant. Elevated winter temperatures tended to decrease stem freezing tolerance during cold acclimation and deacclimation, but it did not increase the risk of freeze-induced damage mid-winter. Plants at elevated temperature showed decreased levels of sucrose in stems of both cultivars and flower buds of ‘Narve Viking’, which, in buds, was associated with increased concentrations of glucose and fructose. Hence, winter warming influences carbohydrate metabolism, but it remains to be elucidated whether decreased sucrose levels account for any changes in freezing tolerance. Our results demonstrate that even a slight increase in winter temperature may alter phenological traits in blackcurrant, but to various extents depending on genotype-specific differences in chilling requirement. PMID:25802249

  20. The Anillin-Related Region of Bud4 Is the Major Functional Determinant for Bud4's Function in Septin Organization during Bud Growth and Axial Bud Site Selection in Budding Yeast

    PubMed Central

    Wu, Huan; Guo, Jia; Zhou, Ya-Ting

    2015-01-01

    The anillin-related protein Bud4 of Saccharomyces cerevisiae is required for axial bud site selection by linking the axial landmark to the septins, which localize at the mother bud neck. Recent studies indicate that Bud4 plays a role in septin organization during cytokinesis. Here we show that Bud4 is also involved in septin organization during bud growth prior to cytokinesis, as bud4? shs1? cells displayed an elongated bud morphology and defective septin organization at 18C. Bud4 overexpression also affected septin organization during bud growth in shs1? cells at 30C. Bud4 was previously thought to associate with the septins via its central region, while the C-terminal anillin-related region was not involved in septin association. Surprisingly, we found that the central region of Bud4 alone targets to the bud neck throughout the cell cycle, unlike full-length Bud4, which localizes to the bud neck only during G2/M phase. We identified the anillin-related region to be a second targeting domain that cooperates with the central region for proper septin association. In addition, the anillin-related region could largely mediate Bud4's function in septin organization during bud growth and bud site selection. We show that this region interacts with the C terminus of Bud3 and the two segments depend on each other for association with the septins. Moreover, like the bud4? mutant, the bud3? mutant genetically interacts with shs1? and cdc12-6 mutants in septin organization, suggesting that Bud4 and Bud3 may cooperate in septin organization during bud growth. These observations provide new insights into the interaction of Bud4 with the septins and Bud3. PMID:25576483

  1. 30 CFR 18.37 - Lead entrances.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Lead entrances. 18.37 Section 18.37 Mineral... § 18.37 Lead entrances. (a) Insulated cable(s), which must extend through an outside wall of an explosion-proof enclosure, shall pass through a stuffing-box lead entrance. All sharp edges that...

  2. 30 CFR 18.37 - Lead entrances.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Lead entrances. 18.37 Section 18.37 Mineral... § 18.37 Lead entrances. (a) Insulated cable(s), which must extend through an outside wall of an explosion-proof enclosure, shall pass through a stuffing-box lead entrance. All sharp edges that...

  3. 30 CFR 18.37 - Lead entrances.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Lead entrances. 18.37 Section 18.37 Mineral... § 18.37 Lead entrances. (a) Insulated cable(s), which must extend through an outside wall of an explosion-proof enclosure, shall pass through a stuffing-box lead entrance. All sharp edges that...

  4. 30 CFR 18.37 - Lead entrances.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Lead entrances. 18.37 Section 18.37 Mineral... § 18.37 Lead entrances. (a) Insulated cable(s), which must extend through an outside wall of an explosion-proof enclosure, shall pass through a stuffing-box lead entrance. All sharp edges that...

  5. 30 CFR 18.37 - Lead entrances.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Lead entrances. 18.37 Section 18.37 Mineral... § 18.37 Lead entrances. (a) Insulated cable(s), which must extend through an outside wall of an explosion-proof enclosure, shall pass through a stuffing-box lead entrance. All sharp edges that...

  6. Perception of photoperiod in individual buds of mature trees regulates leaf-out.

    PubMed

    Zohner, Constantin M; Renner, Susanne S

    2015-12-01

    Experimental data on the perception of day length and temperature in dormant temperate zone trees are surprisingly scarce. In order to investigate when and where these environmental signals are perceived, we carried out bagging experiments in which buds on branches of Fagus sylvatica, Aesculus hippocastanum and Picea abies trees were exposed to natural light increase or kept at constant 8-h days from December until June. Parallel experiments used twigs cut from the same trees, harvesting treated and control twigs seven times and then exposing them to 8- or 16-h days in a glasshouse. Under 8-h days, budburst in Fagus outdoors was delayed by 41 d and in Aesculus by 4 d; in Picea, day length had no effect. Buds on nearby branches reacted autonomously, and leaf primordia only reacted to light cues in late dormancy after accumulating warm days. Experiments applying different wavelength spectra and high-resolution spectrometry to buds indicate a phytochrome-mediated photoperiod control. By demonstrating local photoperiodic control of buds, revealing the time when these signals are perceived, and showing the interplay between photoperiod and chilling, this study contributes to improved modelling of the impact of climate warming on photosensitive species. PMID:26096967

  7. Role of metabolism in ABA homeostasis during potato tuber dormancy

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Endogenous hormones play a essential role in the regulation of potato tuber dormancy. Abscisic acid has been shown to be critically involved in tuber dormancy induction and maintenance. Genes encoding enzymes catalyzing the terminal steps of ABA synthesis and metabolism have been cloned from tuber...

  8. Rapid cycling of potato tuber generations by overcoming dormancy

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Dormancy hinders progress in attempts to fast track potato tuber generations. In this study, we evaluated the ability of gibberellic acid (GA) to overcome dormancy in freshly harvested tubers of eleven potato cultivars in two years of field trials. Tubers were wounded and dipped in 0, 10, 100, and 1...

  9. Chemical Manipulation of Meristem Dormancy Alters Transcript Profiles in Potato

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The dormancy status of potato tuber meristems can be manipulated by a variety of chemical treatments. The application of bromoethane (BE) results in dormancy cessation, while chlorpropham (CIPC), and 1,4-dimethyl naphthalene (DMN) are used commercially to prolong the dormant state. Transcript analys...

  10. Dormancy-Status Pool Dynamics in Indian Ricegrass

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Germination of Indian ricegrass (Achnatherum hymenoides [Roem. & Schult] Barkworth) (Poaceae), a rangeland species native to western North America, is limited by persistent mechanical and physiological dormancy. We previously selected high (HD 3-15) and low-dormancy (LD 6-6) lines from the cv. Rimr...

  11. Apical dominance in saffron and the involvement of the branching enzymes CCD7 and CCD8 in the control of bud sprouting

    PubMed Central

    2014-01-01

    Background In saffron (Crocus sativus), new corms develop at the base of every shoot developed from the maternal corm, a globular underground storage stem. Since the degree of bud sprouts influences the number and size of new corms, and strigolactones (SLs) suppress growth of pre-formed axillary bud, it was considered appropriate to investigate SL involvement in physiology and molecular biology in saffron. We focused on two of the genes within the SL pathway, CCD7 and CCD8, encoding carotenoid cleavage enzymes required for the production of SLs. Results The CsCCD7 and CsCCD8 genes are the first ones isolated and characterized from a non-grass monocotyledonous plant. CsCCD7 and CsCCD8 expression showed some overlapping, although they were not identical. CsCCD8 was highly expressed in quiescent axillary buds and decapitation dramatically reduced its expression levels, suggesting its involvement in the suppression of axillary bud outgrowth. Furthermore, in vitro experiments showed also the involvement of auxin, cytokinin and jasmonic acid on the sprouting of axillary buds from corms in which the apical bud was removed. In addition, CsCCD8 expression, but not CsCCD7, was higher in the newly developed vascular tissue of axillary buds compared to the vascular tissue of the apical bud. Conclusions We showed that production and transport of auxin in saffron corms could act synergistically with SLs to arrest the outgrowth of the axillary buds, similar to the control of above-ground shoot branching. In addition, jasmonic acid seems to play a prominent role in bud dormancy in saffron. While cytokinins from roots promote bud outgrowth. In addition the expression results of CsCCD8 suggest that SLs could positively regulate procambial activity and the development of new vascular tissues connecting leaves with the mother corm. PMID:24947472

  12. Functional and expression analyses of kiwifruit SOC1-like genes suggest that they may not have a role in the transition to flowering but may affect the duration of dormancy

    PubMed Central

    Voogd, Charlotte; Wang, Tianchi; Varkonyi-Gasic, Erika

    2015-01-01

    The MADS-domain transcription factor SUPPRESSOR OF OVEREXPRESSION OF CONSTANS1 (SOC1) is one of the key integrators of endogenous and environmental signals that promote flowering in the annual species Arabidopsis thaliana. In the deciduous woody perennial vine kiwifruit (Actinidia spp.), environmental signals are integrated to regulate annual cycles of growth and dormancy. Accumulation of chilling during winter is required for dormancy break and flowering in spring. In order to understand the regulation of dormancy and flowering in kiwifruit, nine kiwifruit SOC1-like genes were identified and characterized. All genes affected flowering time of A. thaliana Col-0 and were able to rescue the late flowering phenotype of the soc1-2 mutant when ectopically expressed. A differential capacity for homodimerization was observed, but all proteins were capable of strong interactions with SHORT VEGETATIVE PHASE (SVP) MADS-domain proteins. Largely overlapping spatial domains but distinct expression profiles in buds were identified between the SOC1-like gene family members. Ectopic expression of AcSOC1e, AcSOC1i, and AcSOC1f in Actinidia chinensis had no impact on establishment of winter dormancy and failed to induce precocious flowering, but AcSOC1i reduced the duration of dormancy in the absence of winter chilling. These findings add to our understanding of the SOC1-like gene family and the potential diversification of SOC1 function in woody perennials. PMID:25979999

  13. Functional and expression analyses of kiwifruit SOC1-like genes suggest that they may not have a role in the transition to flowering but may affect the duration of dormancy.

    PubMed

    Voogd, Charlotte; Wang, Tianchi; Varkonyi-Gasic, Erika

    2015-08-01

    The MADS-domain transcription factor SUPPRESSOR OF OVEREXPRESSION OF CONSTANS1 (SOC1) is one of the key integrators of endogenous and environmental signals that promote flowering in the annual species Arabidopsis thaliana. In the deciduous woody perennial vine kiwifruit (Actinidia spp.), environmental signals are integrated to regulate annual cycles of growth and dormancy. Accumulation of chilling during winter is required for dormancy break and flowering in spring. In order to understand the regulation of dormancy and flowering in kiwifruit, nine kiwifruit SOC1-like genes were identified and characterized. All genes affected flowering time of A. thaliana Col-0 and were able to rescue the late flowering phenotype of the soc1-2 mutant when ectopically expressed. A differential capacity for homodimerization was observed, but all proteins were capable of strong interactions with SHORT VEGETATIVE PHASE (SVP) MADS-domain proteins. Largely overlapping spatial domains but distinct expression profiles in buds were identified between the SOC1-like gene family members. Ectopic expression of AcSOC1e, AcSOC1i, and AcSOC1f in Actinidia chinensis had no impact on establishment of winter dormancy and failed to induce precocious flowering, but AcSOC1i reduced the duration of dormancy in the absence of winter chilling. These findings add to our understanding of the SOC1-like gene family and the potential diversification of SOC1 function in woody perennials. PMID:25979999

  14. Polysome Formation in Light-controlled Dormancy

    PubMed Central

    Mitchell, Rosemary C.; Villiers, T. A.

    1972-01-01

    Lettuce (Lactuca sativa) seeds var. Grand Rapids could be maintained many weeks in the dark without germination. Following illumination with white light, a gradual increase in polyribosome population up to the time of germination was demonstrated by sucrose gradient centrifugation. Polysomes could not be detected in imbibed seeds maintained continuously in the dark. Thus, polysome formation and therefore the capacity for a high rate of protein synthesis required for germination and growth, is not associated with the process of imbibition, but is dependent upon the seeds having received the dormancy-breaking stimulus of illumination. Images PMID:16658240

  15. Dormancy-breaking requirements of Sophora tomentosa and Erythrina speciosa (Fabaceae) seeds.

    PubMed

    Luzia Delgado, Carolina Maria; Souza de Paula, Alexandre; Santos, Marisa; Silveira Paulilo, Maria Terezinha

    2015-03-01

    The physical dormancy of seeds has been poorly studied in species from tropical forests, such as the Atlantic Forest. This study aimed to examine the effect of moderate alternating temperatures on breaking the physical dormancy of seeds, the morphoanatomy and histochemistry of seed coats, and to locate the structure/region responsible for water entrance into the seed, after breaking the physical dormancy of seeds of two woody Fabaceae (subfamily Faboideae) species that occur in the Brazilian Atlantic Forest: Sophora tomentosa and Erythrina speciosa. To assess temperature effect, seeds were incubated in several temperature values that occur in the Atlantic Forest. For morphological and histochemical studies, sections of fixed seeds were subjected to different reagents, and were observed using light or epifluorescence microscopy, to analyze the anatomy and histochemistry of the seed coat. Treated and nonreated seeds were also analyzed using a scanning electron microscope (SEM) to observe the morphology of the seed coat. To localize the specific site of water entrance, the seeds were blocked with glue in different regions and also immersed in ink. In the present work a maximum temperature fluctuation of 15 degrees C was applied during a period of 20 days and these conditions did not increase the germination of S. tomentosa or E. speciosa. These results may indicate that these seeds require larger fluctuation of temperature than the applied or/and longer period of exposition to the temperature fluctuation. Blocking experiments water inlet combined with SEM analysis of the structures of seed coat for both species showed that besides the lens, the hilum and micropyle are involved in water absorption in seeds scarified with hot water. In seeds of E. speciosa the immersion of scarified seeds into an aniline aqueous solution showed that the solution first entered the seed through the hilum. Both species showed seed morphological and anatomical features for seed coats of the subfamily Faboideae. Lignin and callose were found around all palisade layers and the water impermeability and ecological role of these substances are discussed in the work. PMID:26299132

  16. LEAFY SPURGE (EUPHORBIA ESULA) SEED DORMANCY.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Leafy spurge is a herbaceous perennial weed that reproduces asexually through adventitious vegetative buds and sexually by seed. Seeds can remain viable in the soil for up to 8 yr. The objectives of this research were to identify seed components which restrict germination and to determine if afterri...

  17. Starvation-induced dormancy in E. coli

    NASA Astrophysics Data System (ADS)

    Simsek, Emrah; Kim, Minsu

    Isogenic bacterial populations can exhibit phenotypic heterogeneity. Phenotypic heterogeneity is often viewed as a bet-hedging strategy to cope with environmental fluctuations, and believed to be under genetic control. The experimental evidence of this view, however, is limited. Here, we report experimental evidence that prompts reconsideration of this view. Observing how starved E. coli cells resume growth upon nutrient upshift at the single-cell level in real time, we revealed that physiological and metabolic state of starved cells, as well as growth resumption kinetics, vary from cell to cell. Upon nutrient upshift, a majority of cells resume growth instantly, but a small fraction maintain a non-growth state for several hours or days (i.e., long lag time). Hence they are dormant cells. The fraction strongly depends on the duration of starvation. The dormancy does not confer resistance to starvation. Oxidative damage accumulated during starvation leads to the appearance of dormant cells. Taken together, our data suggests that a dormant subpopulation appears as an inevitable consequence of starvation, rather than cellular decision to cope with starvation. Hence, the existence of a genetic program and adaptive value as a bet-hedging strategy to cope with starvation stress may not be needed to explain the emergence of bacterial dormancy.

  18. Microbial dormancy improves development and experimental validation of ecosystem model

    SciTech Connect

    Wang, Gangsheng; Jagadamma, Sindhu; Mayes, Melanie; Schadt, Christopher Warren; Steinweg, Jessica M; Gu, Lianhong; Post, Wilfred M

    2015-01-01

    Climate feedbacks from soils can result from environmental change followed by response of plant and microbial communities, and/or associated changes in nutrient cycling. Explicit consideration of microbial life history traits and functions may be necessary to predict climate feedbacks due to changes in the physiology and community composition of microbes and their associated effect on carbon cycling. Here, we enhanced the Microbial-Enzyme-mediated Decomposition (MEND) model by incorporating microbial dormancy and the ability to track multiple isotopes of carbon. We tested two versions of MEND, i.e., MEND with dormancy and MEND without dormancy, against long-term (270 d) lab incubations of four soils with isotopically-labeled substrates. MEND without dormancy adequately fitted multiple observations (total and 14C respiration, and dissolved organic carbon), but at the cost of significantly underestimating the total microbial biomass. The MEND with dormancy improved estimates of microbial biomass by 20 71% over the MEND without dormancy. We observed large differences for two fitted model parameters, the specific maintenance and growth rates for active microbes, depending on whether dormancy was considered. Together our model extrapolations of the incubation study show that long-term soil incubations with observations in multiple carbon pools are necessary to estimate both decomposition and microbial parameters. These efforts should provide essential support to future field- and global-scale simulations and enable more confident predictions of feedbacks between environmental change and carbon cycling.

  19. Microbial dormancy improves development and experimental validation of ecosystem model

    DOE PAGESBeta

    Wang, Gangsheng; Jagadamma, Sindhu; Mayes, Melanie; Schadt, Christopher Warren; Steinweg, Jessica M; Gu, Lianhong; Post, Wilfred M

    2015-01-01

    Climate feedbacks from soils can result from environmental change followed by response of plant and microbial communities, and/or associated changes in nutrient cycling. Explicit consideration of microbial life history traits and functions may be necessary to predict climate feedbacks due to changes in the physiology and community composition of microbes and their associated effect on carbon cycling. Here, we enhanced the Microbial-Enzyme-mediated Decomposition (MEND) model by incorporating microbial dormancy and the ability to track multiple isotopes of carbon. We tested two versions of MEND, i.e., MEND with dormancy and MEND without dormancy, against long-term (270 d) lab incubations of fourmore » soils with isotopically-labeled substrates. MEND without dormancy adequately fitted multiple observations (total and 14C respiration, and dissolved organic carbon), but at the cost of significantly underestimating the total microbial biomass. The MEND with dormancy improved estimates of microbial biomass by 20 71% over the MEND without dormancy. We observed large differences for two fitted model parameters, the specific maintenance and growth rates for active microbes, depending on whether dormancy was considered. Together our model extrapolations of the incubation study show that long-term soil incubations with observations in multiple carbon pools are necessary to estimate both decomposition and microbial parameters. These efforts should provide essential support to future field- and global-scale simulations and enable more confident predictions of feedbacks between environmental change and carbon cycling.« less

  20. The roles of auxin in seed dormancy and germination.

    PubMed

    Haiwei, Shuai; Yongjie, Meng; Xiaofeng, Luo; Feng, Chen; Ying, Qi; Wenyu, Yang; Kai, Shu

    2016-04-01

    Seed dormancy and germination are attractive topics in the fields of plant molecular biology as they are key stages during plant growth and development. Seed dormancy is intricately regulated by complex networks of phytohormones and numerous key genes, combined with diverse environmental cues. The transition from dormancy to germination is a very important biological process, and extensive studies have demonstrated that phytohormones abscisic acid (ABA) and gibberellin acid (GA) are major determinants. Consequently, the precise balance between ABA and GA can ensure that the seeds remain dormant under stress conditions and germinate at optimal times. Here we review the role of auxin in seed dormancy and germination. Auxin is one of the classic phytohormones effective during tropism growth and tissue differentiation. Recent studies, however, show that auxin possesses positive effects on seed dormancy, which suggests that auxin is the second phytohormone that induces seed dormancy, besides ABA. We will focus on the synthetic effects in detail between auxin and ABA pathways on seed dormancy and propose future research directions. PMID:27103455

  1. Dormancy and germination: How does the crop seed decide?

    PubMed

    Shu, K; Meng, Y J; Shuai, H W; Liu, W G; Du, J B; Liu, J; Yang, W Y

    2015-11-01

    Whether seeds germinate or maintain dormancy is decided upon through very intricate physiological processes. Correct timing of these processes is most important for the plants life cycle. If moist conditions are encountered, a low dormancy level causes pre-harvest sprouting in various crop species, such as wheat, corn and rice, this decreases crop yield and negatively impacts downstream industrial processing. In contrast, a deep level of seed dormancy prevents normal germination even under favourable conditions, resulting in a low emergence rate during agricultural production. Therefore, an optimal seed dormancy level is valuable for modern mechanised agricultural systems. Over the past several years, numerous studies have demonstrated that diverse endogenous and environmental factors regulate the balance between dormancy and germination, such as light, temperature, water status and bacteria in soil, and phytohormones such as ABA (abscisic acid) and GA (gibberellic acid). In this updated review, we highlight recent advances regarding the molecular mechanisms underlying regulation of seed dormancy and germination processes, including the external environmental and internal hormonal cues, and primarily focusing on the staple crop species. Furthermore, future challenges and research directions for developing a full understanding of crop seed dormancy and germination are also discussed. PMID:26095078

  2. Functional genomics of seed dormancy in wheat: advances and prospects.

    PubMed

    Gao, Feng; Ayele, Belay T

    2014-01-01

    Seed dormancy is a mechanism underlying the inability of viable seeds to germinate under optimal environmental conditions. To achieve rapid and uniform germination, wheat and other cereal crops have been selected against dormancy. As a result, most of the modern commercial cultivars have low level of seed dormancy and are susceptible to preharvest sprouting when wet and moist conditions occur prior to harvest. As it causes substantial loss in grain yield and quality, preharvest sprouting is an ever-present major constraint to the production of wheat. The significance of the problem emphasizes the need to incorporate an intermediate level of dormancy into elite wheat cultivars, and this requires detailed dissection of the mechanisms underlying the regulation of seed dormancy and preharvest sprouting. Seed dormancy research in wheat often involves after-ripening, a period of dry storage during which seeds lose dormancy, or comparative analysis of seeds derived from dormant and non-dormant cultivars. The increasing development in wheat genomic resources along with the application of transcriptomics, proteomics, and metabolomics approaches in studying wheat seed dormancy have extended our knowledge of the mechanisms acting at transcriptional and post-transcriptional levels. Recent progresses indicate that some of the molecular mechanisms are associated with hormonal pathways, epigenetic regulations, targeted oxidative modifications of seed mRNAs and proteins, redox regulation of seed protein thiols, and modulation of translational activities. Given that preharvest sprouting is closely associated with seed dormancy, these findings will significantly contribute to the designing of efficient strategies for breeding preharvest sprouting tolerant wheat. PMID:25309557

  3. Stratification Requirements for Seed Dormancy Alleviation in a Wetland Weed

    PubMed Central

    Boddy, Louis G.; Bradford, Kent J.; Fischer, Albert J.

    2013-01-01

    Echinochloaoryzicola(syn.E. phyllopogon) is an exotic weed of California rice paddies that has evolved resistance to multiple herbicides. Elimination of seedlingsthroughcertain weed control methods can limit the spread of this weed, but is contingent on accurate predictions of germination and emergence timing, which are influenced by seed dormancy levels.In summer annuals, dormancy can often be relieved through stratification, a period of prolonged exposure to cold and moist conditions.We used population-based threshold models to quantify the effects of stratification on seed germination of four E. Oryzicola populations at a range of water potential (Ψ) and oxygen levels. We also determined how stratification temperatures, moisture levels and durations contributed to dormancy release. Stratification released dormancy by decreasing base Ψ and hydrotimerequired for germination and by eliminating any germination sensitivity to oxygen. Stratification also increased average germination rates (GR), which were used as a proxy for relative dormancy levels. Alternating temperatures nearly doubled GR in all populations, indicating that seeds could be partially dormant despite achieving high final germination percentages. Stratification at Ψ = 0 MPa increased GR compared to stratification at lower water potentials, demonstrating that Ψ contributed to regulating dormancy release. Maximum GR occurred after 2-4 weeks of stratification at 0 MPa; GR were often more rapid for herbicide-resistant than for herbicide-susceptible seeds, implying greater dormancy in the latter. Manipulation of field conditions to promote dormancy alleviation of E. oryzicola seeds might improve the rate and uniformity of germination for seed bank depletion through seedling weed control. Our results suggest field soil saturation in winter would contribute towards E. oryzicola dormancy release and decrease the time to seedling emergence. PMID:24039714

  4. Functional genomics of seed dormancy in wheat: advances and prospects

    PubMed Central

    Gao, Feng; Ayele, Belay T.

    2014-01-01

    Seed dormancy is a mechanism underlying the inability of viable seeds to germinate under optimal environmental conditions. To achieve rapid and uniform germination, wheat and other cereal crops have been selected against dormancy. As a result, most of the modern commercial cultivars have low level of seed dormancy and are susceptible to preharvest sprouting when wet and moist conditions occur prior to harvest. As it causes substantial loss in grain yield and quality, preharvest sprouting is an ever-present major constraint to the production of wheat. The significance of the problem emphasizes the need to incorporate an intermediate level of dormancy into elite wheat cultivars, and this requires detailed dissection of the mechanisms underlying the regulation of seed dormancy and preharvest sprouting. Seed dormancy research in wheat often involves after-ripening, a period of dry storage during which seeds lose dormancy, or comparative analysis of seeds derived from dormant and non-dormant cultivars. The increasing development in wheat genomic resources along with the application of transcriptomics, proteomics, and metabolomics approaches in studying wheat seed dormancy have extended our knowledge of the mechanisms acting at transcriptional and post-transcriptional levels. Recent progresses indicate that some of the molecular mechanisms are associated with hormonal pathways, epigenetic regulations, targeted oxidative modifications of seed mRNAs and proteins, redox regulation of seed protein thiols, and modulation of translational activities. Given that preharvest sprouting is closely associated with seed dormancy, these findings will significantly contribute to the designing of efficient strategies for breeding preharvest sprouting tolerant wheat. PMID:25309557

  5. Bud-Neck Scaffolding as a Possible Driving Force in ESCRT-Induced Membrane Budding

    PubMed Central

    Mercker, Moritz; Marciniak-Czochra, Anna

    2015-01-01

    Membrane budding is essential for processes such as protein sorting and transport. Recent experimental results with ESCRT proteins reveal a novel budding mechanism, with proteins emerging in bud necks but separated from the entire bud surface. Using an elastic model, we show that ESCRT protein shapes are sufficient to spontaneously create experimentally observed structures, with protein-membrane interactions leading to protein scaffolds in bud-neck regions. Furthermore, the model reproduces experimentally observed budding directions and bud sizes. Finally, our results reveal that membrane-mediated sorting has the capability of creating structures more complicated than previously assumed. PMID:25692588

  6. The perivascular niche regulates breast tumour dormancy.

    PubMed

    Ghajar, Cyrus M; Peinado, Héctor; Mori, Hidetoshi; Matei, Irina R; Evason, Kimberley J; Brazier, Hélène; Almeida, Dena; Koller, Antonius; Hajjar, Katherine A; Stainier, Didier Y R; Chen, Emily I; Lyden, David; Bissell, Mina J

    2013-07-01

    In a significant fraction of breast cancer patients, distant metastases emerge after years or even decades of latency. How disseminated tumour cells (DTCs) are kept dormant, and what wakes them up, are fundamental problems in tumour biology. To address these questions, we used metastasis assays in mice and showed that dormant DTCs reside on microvasculature of lung, bone marrow and brain. We then engineered organotypic microvascular niches to determine whether endothelial cells directly influence breast cancer cell (BCC) growth. These models demonstrated that endothelial-derived thrombospondin-1 induces sustained BCC quiescence. This suppressive cue was lost in sprouting neovasculature; time-lapse analysis showed that sprouting vessels not only permit, but accelerate BCC outgrowth. We confirmed this surprising result in dormancy models and in zebrafish, and identified active TGF-β1 and periostin as tumour-promoting factors derived from endothelial tip cells. Our work reveals that stable microvasculature constitutes a dormant niche, whereas sprouting neovasculature sparks micrometastatic outgrowth. PMID:23728425

  7. Oxidative signaling in seed germination and dormancy

    PubMed Central

    El-Maarouf-Bouteau, Hayat

    2008-01-01

    Reactive Oxygen Species (ROS) play a key role in various events of seed life. In orthodox seeds, ROS are produced from embryogenesis to germination, i.e., in metabolically active cells, but also in quiescent dry tissues during after ripening and storage, owing various mechanisms depending on the seed moisture content. Although ROS have been up to now widely considered as detrimental to seeds, recent advances in plant physiology signaling pathways has lead to reconsider their role. ROS accumulation can therefore be also beneficial for seed germination and seedling growth by regulating cellular growth, ensuring a protection against pathogens or controlling the cell redox status. ROS probably also act as a positive signal in seed dormancy release. They interact with abscisic acid and gibberellins transduction pathway and are likely to control numerous transcription factors and properties of specific protein through their carbonylation. PMID:19513212

  8. "PROBATION AT ENTRANCE"--A STUDY.

    ERIC Educational Resources Information Center

    LUKE, ORRAL S.

    PERSISTENCY AND SUCCESS OF 200 FALL, 1962, "PROBATION AT ENTRANCE" STUDENTS (WITH LESS THAN 2.0 GRADE POINT AVERAGE) WAS STUDIED. PERCENTAGE OF MEN AND WOMEN FROM VARIOUS HIGH SCHOOLS, MEDIAN ENTRANCE TEST SCORES, MAJOR FIELDS CHOSEN, AND EXTRACURRICULAR ACTIVITIES WERE ENUMERATED. THE MAJORITY OF STUDENTS CHOSE GOALS WITHIN THEIR ABILITY LEVELS,…

  9. 46 CFR 310.6 - Entrance requirements.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 8 2013-10-01 2013-10-01 false Entrance requirements. 310.6 Section 310.6 Shipping MARITIME ADMINISTRATION, DEPARTMENT OF TRANSPORTATION TRAINING MERCHANT MARINE TRAINING Regulations and Minimum Standards for State, Territorial or Regional Maritime Academies and Colleges § 310.6 Entrance requirements. (a) Enrollment prior to April...

  10. ULTRAVIOLET MICROSCOPY OF BUDDING SACCHAROMYCES

    PubMed Central

    McClary, Dan O.; Bowers, Wilbert D.; Miller, Glendon R.

    1962-01-01

    McClary, Dan O. (Southern Illinois University, Carbondale), Wilbert D. Bowers, Jr., and Glendon R. Miller. Ultraviolet microscopy of budding Saccharomyces. J. Bacteriol. 83:276283. 1962.Synchronous cell division was obtained in Saccharomyces by transferring starved cells into nutrient medium. Ultraviolet microscopy and Giemsa-stained preparations of these cells showed nuclear division to occur in the mother cell early in the budding process. The divided nucleus passed into the neck between the mother cell and the bud, and either fused together again or the two parts became so closely associated that one continuous dumbbell-shaped body was seen which seemed to divide by constriction. This effect was probably due to the retention of the intact nuclear membrane until nuclear division was otherwise complete. The nuclear apparatus lies outside the vacuole. The extent to which these bodies function together cannot be determined by the techniques employed in this work. Parallel experiments on meristematic cells of onion root tips show the reliability of these cytological methods. Images PMID:16561928

  11. Using Generic Data to Establish Dormancy Failure Rates

    NASA Technical Reports Server (NTRS)

    Reistle, Bruce

    2014-01-01

    Many hardware items are dormant prior to being operated. The dormant period might be especially long, for example during missions to the moon or Mars. In missions with long dormant periods the risk incurred during dormancy can exceed the active risk contribution. Probabilistic Risk Assessments (PRAs) need to account for the dormant risk contribution as well as the active contribution. A typical method for calculating a dormant failure rate is to multiply the active failure rate by a constant, the dormancy factor. For example, some practitioners use a heuristic and divide the active failure rate by 30 to obtain an estimate of the dormant failure rate. To obtain a more empirical estimate of the dormancy factor, this paper uses the recently updated database NPRD-2011 [1] to arrive at a set of distributions for the dormancy factor. The resulting dormancy factor distributions are significantly different depending on whether the item is electrical, mechanical, or electro-mechanical. Additionally, this paper will show that using a heuristic constant fails to capture the uncertainty of the possible dormancy factors.

  12. Coevolutionary patterning of teeth and taste buds.

    PubMed

    Bloomquist, Ryan F; Parnell, Nicholas F; Phillips, Kristine A; Fowler, Teresa E; Yu, Tian Y; Sharpe, Paul T; Streelman, J Todd

    2015-11-01

    Teeth and taste buds are iteratively patterned structures that line the oro-pharynx of vertebrates. Biologists do not fully understand how teeth and taste buds develop from undifferentiated epithelium or how variation in organ density is regulated. These organs are typically studied independently because of their separate anatomical location in mammals: teeth on the jaw margin and taste buds on the tongue. However, in many aquatic animals like bony fishes, teeth and taste buds are colocalized one next to the other. Using genetic mapping in cichlid fishes, we identified shared loci controlling a positive correlation between tooth and taste bud densities. Genome intervals contained candidate genes expressed in tooth and taste bud fields. sfrp5 and bmper, notable for roles in Wingless (Wnt) and bone morphogenetic protein (BMP) signaling, were differentially expressed across cichlid species with divergent tooth and taste bud density, and were expressed in the development of both organs in mice. Synexpression analysis and chemical manipulation of Wnt, BMP, and Hedgehog (Hh) pathways suggest that a common cichlid oral lamina is competent to form teeth or taste buds. Wnt signaling couples tooth and taste bud density and BMP and Hh mediate distinct organ identity. Synthesizing data from fish and mouse, we suggest that the Wnt-BMP-Hh regulatory hierarchy that configures teeth and taste buds on mammalian jaws and tongues may be an evolutionary remnant inherited from ancestors wherein these organs were copatterned from common epithelium. PMID:26483492

  13. Coevolutionary patterning of teeth and taste buds

    PubMed Central

    Bloomquist, Ryan F.; Parnell, Nicholas F.; Phillips, Kristine A.; Fowler, Teresa E.; Yu, Tian Y.; Sharpe, Paul T.; Streelman, J. Todd

    2015-01-01

    Teeth and taste buds are iteratively patterned structures that line the oro-pharynx of vertebrates. Biologists do not fully understand how teeth and taste buds develop from undifferentiated epithelium or how variation in organ density is regulated. These organs are typically studied independently because of their separate anatomical location in mammals: teeth on the jaw margin and taste buds on the tongue. However, in many aquatic animals like bony fishes, teeth and taste buds are colocalized one next to the other. Using genetic mapping in cichlid fishes, we identified shared loci controlling a positive correlation between tooth and taste bud densities. Genome intervals contained candidate genes expressed in tooth and taste bud fields. sfrp5 and bmper, notable for roles in Wingless (Wnt) and bone morphogenetic protein (BMP) signaling, were differentially expressed across cichlid species with divergent tooth and taste bud density, and were expressed in the development of both organs in mice. Synexpression analysis and chemical manipulation of Wnt, BMP, and Hedgehog (Hh) pathways suggest that a common cichlid oral lamina is competent to form teeth or taste buds. Wnt signaling couples tooth and taste bud density and BMP and Hh mediate distinct organ identity. Synthesizing data from fish and mouse, we suggest that the Wnt-BMP-Hh regulatory hierarchy that configures teeth and taste buds on mammalian jaws and tongues may be an evolutionary remnant inherited from ancestors wherein these organs were copatterned from common epithelium. PMID:26483492

  14. Candidate Cave Entrances on Mars

    NASA Astrophysics Data System (ADS)

    Cushing, Glen

    2012-04-01

    This paper presents newly discovered candidate cave entrances into Martian near-surface lava tubes, volcano-tectonic fracture systems, and pit craters and describes their characteristics and exploration possibilities. These candidates are all collapse features that occur either intermittently along laterally continuous trench-like depressions or in the floors of sheer-walled atypical pit craters. As viewed from orbit, locations of most candidates are visibly consistent with known terrestrial features such as tube-fed lava flows, volcano-tectonic fractures, and pit craters, each of which forms by mechanisms that can produce caves. Although we cannot determine subsurface extents of the Martian features discussed here, some may continue unimpeded for many kilometers if terrestrial examples are indeed analogous. The features presented here were identified in images acquired by the Mars Odyssey's Thermal Emission Imaging System visiblewavelength camera, and by the Mars Reconnaissance Orbiter's Context Camera. Select candidates have since been targeted by the High-Resolution Imaging Science Experiment. Martian caves are promising potential sites for future human habitation and astrobiology investigations; understanding their characteristics is critical for long-term mission planning and for developing the necessary exploration technologies.

  15. Candidate cave entrances on Mars

    USGS Publications Warehouse

    Cushing, Glen E.

    2012-01-01

    This paper presents newly discovered candidate cave entrances into Martian near-surface lava tubes, volcano-tectonic fracture systems, and pit craters and describes their characteristics and exploration possibilities. These candidates are all collapse features that occur either intermittently along laterally continuous trench-like depressions or in the floors of sheer-walled atypical pit craters. As viewed from orbit, locations of most candidates are visibly consistent with known terrestrial features such as tube-fed lava flows, volcano-tectonic fractures, and pit craters, each of which forms by mechanisms that can produce caves. Although we cannot determine subsurface extents of the Martian features discussed here, some may continue unimpeded for many kilometers if terrestrial examples are indeed analogous. The features presented here were identified in images acquired by the Mars Odyssey's Thermal Emission Imaging System visible-wavelength camera, and by the Mars Reconnaissance Orbiter's Context Camera. Select candidates have since been targeted by the High-Resolution Imaging Science Experiment. Martian caves are promising potential sites for future human habitation and astrobiology investigations; understanding their characteristics is critical for long-term mission planning and for developing the necessary exploration technologies.

  16. Reduced Dormancy5 encodes a protein phosphatase 2C that is required for seed dormancy in Arabidopsis.

    PubMed

    Xiang, Yong; Nakabayashi, Kazumi; Ding, Jia; He, Fei; Bentsink, Leónie; Soppe, Wim J J

    2014-11-01

    Seed dormancy determines germination timing and contributes to crop production and the adaptation of natural populations to their environment. Our knowledge about its regulation is limited. In a mutagenesis screen of a highly dormant Arabidopsis thaliana line, the reduced dormancy5 (rdo5) mutant was isolated based on its strongly reduced seed dormancy. Cloning of RDO5 showed that it encodes a PP2C phosphatase. Several PP2C phosphatases belonging to clade A are involved in abscisic acid signaling and control seed dormancy. However, RDO5 does not cluster with clade A phosphatases, and abscisic acid levels and sensitivity are unaltered in the rdo5 mutant. RDO5 transcript could only be detected in seeds and was most abundant in dry seeds. RDO5 was found in cells throughout the embryo and is located in the nucleus. A transcriptome analysis revealed that several genes belonging to the conserved PUF family of RNA binding proteins, in particular Arabidopsis PUMILIO9 (APUM9) and APUM11, showed strongly enhanced transcript levels in rdo5 during seed imbibition. Further transgenic analyses indicated that APUM9 reduces seed dormancy. Interestingly, reduction of APUM transcripts by RNA interference complemented the reduced dormancy phenotype of rdo5, indicating that RDO5 functions by suppressing APUM transcript levels. PMID:25415980

  17. 1. PARKING LOT BEFORE SOUTH ENTRANCE STATION, FACING N. PARK ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. PARKING LOT BEFORE SOUTH ENTRANCE STATION, FACING N. PARK ENTRANCE SIGN IS IN TREES IN CENTER. - South Entrance Road, Between South park boundary & Village Loop Road, Grand Canyon, Coconino County, AZ

  18. Review of Tumor Dormancy Therapy Using Traditional Oriental Herbal Medicine

    PubMed Central

    Lee, Jong-Ho; Koung, Fan-Pei; Cho, Chong-Kwan; Lee, Yeon-Weol; Yoo, Hwa-Seung

    2013-01-01

    Objective: Standard cancer therapy prolongs survival, but can be detrimental to the quality of life, compromise the immune system, and leave residual disease that can cause recurrence years or decades in the future. Tumor dormancy therapy is a novel therapeutic approach that may improve these shortcomings, promote quality of life, and prolong survival. The aim of this study was to analyze studies on dormancy therapy, especially studies using traditional Oriental herbal medicine, so as to evaluate the efficacy of dormancy therapy with traditional oriental herbal medicine. Methods: We conducted a systematic literature review using Scientific and Technical Information Integration Services (NDSL), PubMed, and RISS. We searched for clinical reports, papers, and books related to tumor metastasis, recurrence, immunotherapy, tumor dormancy, and traditional oriental herbal medicine with anticancer effects. Seventy-nine (79) experimental and clinical articles in both Korean and English were reviewed. This study was conducted from March 1, 2012 to May 31, 2012. Results: This approach, Tumor dormancy therapy, rather than seeking to remove the tumor, includes combination of low-dose chemotherapy, immunotherapy, immunosurveillance, and other methods to stabilize tumor growth and to enhance the host is immunity against disseminated tumor cells and thus to manage cancer as a chronic disease while maintaining quality of life. In particular, integrative use of Oriental herbal medicine has been shown to induce or maintain tumor dormancy, increase the effectiveness of conventional chemotherapy, improve quality of life, and prolong survival. Conclusion: Tumor dormancy therapy is a promising novel therapeutic approach that may be especially effective with Oriental herbal medicine. Further research is needed to determine its potential mechanisms and therapeutic applications. PMID:25780657

  19. Taste bud development in the channel catfish.

    PubMed

    Northcutt, R Glenn

    2005-01-31

    Taste bud formation in channel catfish is first seen to occur in stage 39 embryos, when taste bud primordia (stage 1), consisting of three to five cells, including a single calretinin-positive cell, can be recognized within the oropharyngeal cavity and maxillary barbels. Within a short time (stage 40), stage 2 taste bud primordia are apparent and include two or three calretinin-positive cells. The number of calretinin-positive cells continues to increase (stage 3), and the primordia begin to erupt as mature taste buds (stage 4) by embryonic stage 48. This same pattern of taste bud development characterizes other regions of the head, with calretinin-positive cells first detected around the mouth and on the other barbels by stage 41 and on the rest of the head by stage 48. The development of trunk taste buds lags far behind that of the head, with the first calretinin-positive cells occurring on the lobes of the caudal fin by stage 48 and on the remaining fins by stage 50. Taste bud primordia on the trunk proper do not begin to appear until stage 53, when the larvae begin to feed, and these receptors begin to erupt only in 1-week-old larvae. Fibers of the facial nerve, which innervate all external taste buds, ramify within the ectoderm prior to the first appearance of taste bud primordia or their precursors. PMID:15612020

  20. [Impact of TDZ and NAA on adventitious bud induction and cluster bud multiplication in Tulipa edulis].

    PubMed

    Zhu, Li-Fang; Xu, Chao; Zhu, Zai-Biao; Yang, He-Tong; Guo, Qiao-Sheng; Xu, Hong-jian; Ma, Hong-Jian; Zhao, Gui-Hua

    2014-08-01

    To explore the method of explants directly induced bud and establish the tissue culture system of mutiple shoot by means of direct organogenesis, core bud and daughter bulbs (the top of bud stem expanded to form daughter bulb) of T. edulis were used as explants and treated with thidiazuron (TDZ) and 1-naphthlcetic acid (NAA). The results showed that the optimal medium for bud inducted form core bud and daughter bulb were MS + TDZ 2.0 mg x L(-1) + NAA 4.0 mg x L(-1) and MS +TDZ 2.0 mg x L(-1) + NAA 2.0 mg x L(-1) respectively, both of them had a bud induction rate of 72.92%, 79.22%. The optimal medium for cluster buds multiplication was MS + TDZ 0.2 mg x L(-1) + NAA 0.2 mg x L(-1), and proliferation coefficient was 2.23. After proliferation, cluster buds rooting occurred on MS medium with IBA 1.0 mg x L(-1) and the rooting rate was 52.6%, three to five seedlings in each plant. Using core bud and daughter bulb of T. edulis, the optimum medium for adventitious bud directly inducted from daughter bulb, core bud and cluster bud multiplication were screened out and the tissue culture system of multiple shoot by means of direct organogenesis was established. PMID:25509282

  1. Abscisic Acid Levels and Seed Dormancy

    PubMed Central

    Sondheimer, E.; Tzou, D. S.; Galson, Eva C.

    1968-01-01

    Dormant seeds from Fraxinus species require cold-temperature after-ripening prior to germination. Earlier, we found that abscisic acid (ABA) will inhibit germination of excised nondormant embryos and that this can be reversed with a combination of gibberellic acid and kinetin. Using Milborrow's quantitative racemate dilution method the ABA concentration in 3 types of Fraxinus seed and pericarp were determined. While ABA was present in all tissues, the highest concentration was found in the seed and pericarp of dormant F. americana. During the chilling treatment of F. americana the ABA levels decreased 37% in the pericarp and 68% in the seed. The ABA concentration of the seed of the nondormant species, F. ornus, is as low as that found in F. americana seeds after cold treatment. Experiments with exogenously added ABA solutions indicate that it is unlikely that the ABA in the pericarp functions in the regulation of seed dormancy. However, the ABA in the seed does seem to have a regulatory role in germination. Images PMID:16656935

  2. The perivascular niche regulates breast tumor dormancy

    PubMed Central

    Peinado, Héctor; Mori, Hidetoshi; Matei, Irina R.; Evason, Kimberley J.; Brazier, Hélène; Almeida, Dena; Koller, Antonius; Hajjar, Katherine A.; Stainier, Didier Y.R.; Chen, Emily I.; Lyden, David

    2013-01-01

    In a significant fraction of breast cancer patients, distant metastases emerge after years or even decades of latency. How disseminated tumor cells (DTCs) are kept dormant, and what ‘wakes them up’, are fundamental problems in tumor biology. To address these questions, we utilized metastasis assays in mice to show that dormant DTCs reside upon microvasculature of lung, bone marrow and brain. We then engineered organotypic microvascular niches to determine whether endothelial cells directly influence breast cancer cell (BCC) growth. These models demonstrated that endothelial-derived thrombospondin-1 induces sustained BCC quiescence. This suppressive cue was lost in sprouting neovasculature; time-lapse analysis showed that sprouting vessels not only permit, but accelerate BCC outgrowth. We confirmed this surprising result in dormancy models and in zebrafish, and identified active TGF-β1 and periostin as tumor-promoting, endothelial tip cell-derived factors. Our work reveals that stable microvasculature constitutes a ‘dormant niche,’ whereas sprouting neovasculature sparks micrometastatic outgrowth. PMID:23728425

  3. 30 CFR 57.4560 - Mine entrances.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Fire Prevention and Control Installation/construction/maintenance § 57.4560 Mine entrances. For at least 200 feet inside the mine portal...

  4. 30 CFR 57.4560 - Mine entrances.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Fire Prevention and Control Installation/construction/maintenance § 57.4560 Mine entrances. For at least 200 feet inside the mine portal...

  5. Entrance to Yosemite Valley in Fog

    In this image, the entrance to Yosemite Valley may be seen shrouded in fog. Yosemite Valley is a glacially carved valley located within Yosemite National Park. It is part of the Sierra Nevada batholith and is largely composed of granite....

  6. Mechanisms of Cancer Cell Dormancy--Another Hallmark of Cancer?

    PubMed

    Yeh, Albert C; Ramaswamy, Sridhar

    2015-12-01

    Disease relapse in cancer patients many years after clinical remission, often referred to as cancer dormancy, is well documented but remains an incompletely understood phenomenon on the biologic level. Recent reviews have summarized potential models that can explain this phenomenon, including angiogenic, immunologic, and cellular dormancy. We focus on mechanisms of cellular dormancy as newer biologic insights have enabled better understanding of this process. We provide a historical context, synthesize current advances in the field, and propose a mechanistic framework that treats cancer cell dormancy as a dynamic cell state conferring a fitness advantage to an evolving malignancy under stress. Cellular dormancy appears to be an active process that can be toggled through a variety of signaling mechanisms that ultimately downregulate the RAS/MAPK and PI(3)K/AKT pathways, an ability that is preserved even in cancers that constitutively depend on these pathways for their growth and survival. Just as unbridled proliferation is a key hallmark of cancer, the ability of cancer cells to become quiescent may be critical to evolving malignancies, with implications for understanding cancer initiation, progression, and treatment resistance. PMID:26354021

  7. New entrance shade design for SIRTF

    NASA Technical Reports Server (NTRS)

    Davis, Paul K.

    1989-01-01

    A new design for the entrance shade for the Space Infrared Telescope Facility (SIRTF) is presented. The evolution of the entrance shade began with a simple frustum, symmetrical about the telescope axis, when SIRTF was expected to be Shuttle-attached. With the change to a free-flying SIRTF this frustum was cut off at an angle. The telescope will be operated so that whenever not in the earth's shadow the high side is kept toward the sun. However, the entrance shade interior itself will be so warm that the optics, including the secondary mirror and its mechanisms and support structure, will be restricted to the rear part of the barrel, termed the aftbaffle, which is shaded from the interior of the entrance shade by the forebaffle. This is best accomplished by the most recent design in which the axis of the entrance shade is offset from the telescope axis. This results in a shorter entrance shade, shorter forebaffle, and a shaded region within the barrel which is symmetrical about the telescope axis. All of these are advantageous.

  8. Studies on genotypic variability and seed dormancy in sunflower (Helianthus annuus L.)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Seed dormancy is a great drawback and causes a great problem in efficient seed production of sunflower for which great efforts have been made to develop techniques in breaking seed dormancy of sunflower. Studies have indicated that sunflower genotypes showed a large variability in dormancy. Few near...

  9. Pollen development in Rhododendron in relation to winter dormancy and bloom time.

    PubMed

    Mirgorodskaya, Olga E; Koteyeva, Nuria K; Volchanskaya, Alexandra V; Miroslavov, Evgeny A

    2015-09-01

    Microsporogenesis and microgametogenesis of Rhododendron ledebourii (semi-deciduous), Rhododendron luteum (deciduous), and Rhododendron catawbiense (evergreen) were studied by light and electron microscopies in order to determine the stages of pollen development in relation to period of winter dormancy and bloom time throughout an annual growth cycle. Development of generative organs starts in June in R. ledebourii and in July in R. luteum and R. catawbiense and reaches completion about 11 months later. R. luteum and R. catawbiense microspores undergo meiosis at the end of the August and spend winter at the vacuolization stage. Mitosis with the formation of bicellular pollen grain occurs shortly before flowering at the beginning of June. R. ledebourii develops two types of flowers which differ in the timing of microgametogenesis. The first type is characterized by early microspore meiosis and mitosis leading to development of bicellular pollen grains by the end of August, and is prone to fall blooming during warm autumn temperatures. Microspores of the second flower type have a more prolonged vacuolization stage with mitosis and subsequent bicellular pollen grains occurring in November. By winter, flower buds in R. ledebourii are more advanced developmentally than in R. catawbiense and R. luteum, and bloom about 1 month earlier. The different strategies of pollen development identified both within and between these three Rhododendron species were recognized which are not associated with leaf drop during winter but appear to be related to the time of spring flowering and the frequency of autumn flowering. PMID:25643916

  10. Evolution of seed dormancy due to sib competition: effect of dispersal and inbreeding.

    PubMed

    Kobayashi, Y; Yamamura, N

    2000-01-01

    The effect of dispersal and inbreeding on the evolution of seed dormancy to avoid sib competition is theoretically investigated, using a model which assumes a plant population with patchy spatial structure in a constant environment. Applying the inclusive fitness method, the evolutionarily stable dormancy rates are analytically derived for three cases: (a) an asexual haploid population, (b) a diploid-hermaphrodite population in which the dormancy rate is controlled by seeds, and (c) a diploid-hermaphrodite population in which the dormancy rate is controlled by mother plants. The evolutionarily stable dormancy rates decrease in the order of case (c), case (a), and case (b). In all the cases, the evolutionarily stable dormancy rates increase with decreasing the dispersal rate. Although inbreeding generally increases the evolutionarily stable dormancy rates, inbreeding due to selfing reduces the rate exceptionally in case (c). PMID:10623495

  11. Summer dormancy in edible dormice ( Glis glis) without energetic constraints

    NASA Astrophysics Data System (ADS)

    Bieber, Claudia; Ruf, Thomas

    2009-01-01

    Average longevity in free-living edible dormice ( Glis glis) can reach 9 years, which is extremely high for a small rodent. This remarkable life span has been related to a peculiar life history strategy and the rarity of reproductive bouts in these seed eaters. Most females (96%) reproduce only once or twice in their lifetime, predominantly during years of mast seeding of, e.g., beech, but entire populations can skip reproduction in years of low seed availability. Surprisingly, in non-reproductive years, large fractions of populations apparently vanished and were never captured above ground. Therefore, we determined the duration of above-ground activity, and body temperature profiles in a subset of animals, of dormice under semi-natural conditions in outdoor enclosures. We found that non-reproductive dormice returned to dormancy in underground burrows throughout summer after active seasons as short as <2 weeks. Thus, animals spent up to >10 months per year in dormancy. This exceeds dormancy duration of any other mammal under natural conditions. Summer dormancy was not caused by energy constraints, as it occurred in animals in good condition, fed ad libitum and without climatic stress. We suggest that almost year-round torpor has evolved as a strategy to escape birds of prey, the major predators of this arboreal mammal. This unique predator-avoidance strategy clearly helps in explaining the unusually high longevity of dormice.

  12. Scarification and Germination Treatments Break Dormancy of Rubus Species

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The genus Rubus exhibits morphological diversity and a wide range of reproductive systems and habitats. Seeds of blackberry (subgenus Rubus) and raspberry (subg. Idaeobatus) have a deep dormancy caused by one or more mechanisms. Rubus seeds are normally enclosed in a hard schlerenchymatous endocar...

  13. Ethylene, a key factor in the regulation of seed dormancy

    PubMed Central

    Corbineau, Françoise; Xia, Qiong; Bailly, Christophe

    2014-01-01

    Ethylene is an important component of the gaseous environment, and regulates numerous plant developmental processes including seed germination and seedling establishment. Dormancy, the inability to germinate in apparently favorable conditions, has been demonstrated to be regulated by the hormonal balance between abscisic acid (ABA) and gibberellins (GAs). Ethylene plays a key role in dormancy release in numerous species, the effective concentrations allowing the germination of dormant seeds ranging between 0.1 and 200 μL L-1. Studies using inhibitors of ethylene biosynthesis or of ethylene action and analysis of mutant lines altered in genes involved in the ethylene signaling pathway (etr1, ein2, ain1, etr1, and erf1) demonstrate the involvement of ethylene in the regulation of germination and dormancy. Ethylene counteracts ABA effects through a regulation of ABA metabolism and signaling pathways. Moreover, ethylene insensitive mutants in Arabidopsis are more sensitive to ABA and the seeds are more dormant. Numerous data also show an interaction between ABA, GAs and ethylene metabolism and signaling pathways. It has been increasingly demonstrated that reactive oxygen species (ROS) may play a significant role in the regulation of seed germination interacting with hormonal signaling pathways. In the present review the responsiveness of seeds to ethylene will be described, and the key role of ethylene in the regulation of seed dormancy via a crosstalk between hormones and other signals will be discussed. PMID:25346747

  14. New insights into tumor dormancy: Targeting DNA repair pathways

    PubMed Central

    Evans, Elizabeth B; Lin, Shiaw-Yih

    2015-01-01

    Over the past few decades, major strides have advanced the techniques for early detection and treatment of cancer. However, metastatic tumor growth still accounts for the majority of cancer-related deaths worldwide. In fact, breast cancers are notorious for relapsing years or decades after the initial clinical treatment, and this relapse can vary according to the type of breast cancer. In estrogen receptor-positive breast cancers, late tumor relapses frequently occur whereas relapses in estrogen receptor-negative cancers or triple negative tumors arise early resulting in a higher mortality risk. One of the main causes of metastasis is tumor dormancy in which cancer cells remain concealed, asymptomatic, and untraceable over a prolonged period of time. Under certain conditions, dormant cells can re-enter into the cell cycle and resume proliferation leading to recurrence. However, the molecular and cellular regulators underlying this transition remain poorly understood. To date, three mechanisms have been identified to trigger tumor dormancy including cellular, angiogenic, and immunologic dormancies. In addition, recent studies have suggested that DNA repair mechanisms may contribute to the survival of dormant cancer cells. In this article, we summarize the recent experimental and clinical evidence governing cancer dormancy. In addition, we will discuss the role of DNA repair mechanisms in promoting the survival of dormant cells. This information provides mechanistic insight to explain why recurrence occurs, and strategies that may enhance therapeutic approaches to prevent disease recurrence. PMID:26468441

  15. Cellular Adhesion Promotes Prostate Cancer Cells Escape from Dormancy

    PubMed Central

    Ruppender, Nazanin; Larson, Sandy; Lakely, Bryce; Kollath, Lori; Brown, Lisha; Coleman, Ilsa; Coleman, Roger; Nguyen, Holly; Nelson, Peter S.; Corey, Eva; Snyder, Linda A.; Vessella, Robert L.; Morrissey, Colm; Lam, Hung-Ming

    2015-01-01

    Dissemination of prostate cancer (PCa) cells to the bone marrow is an early event in the disease process. In some patients, disseminated tumor cells (DTC) proliferate to form active metastases after a prolonged period of undetectable disease known as tumor dormancy. Identifying mechanisms of PCa dormancy and reactivation remain a challenge partly due to the lack of in vitro models. Here, we characterized in vitro PCa dormancy-reactivation by inducing cells from three patient-derived xenograft (PDX) lines to proliferate through tumor cell contact with each other and with bone marrow stroma. Proliferating PCa cells demonstrated tumor cell-cell contact and integrin clustering by immunofluorescence. Global gene expression analyses on proliferating cells cultured on bone marrow stroma revealed a downregulation of TGFB2 in all of the three proliferating PCa PDX lines when compared to their non-proliferating counterparts. Furthermore, constitutive activation of myosin light chain kinase (MLCK), a downstream effector of integrin-beta1 and TGF-beta2, in non-proliferating cells promoted cell proliferation. This cell proliferation was associated with an upregulation of CDK6 and a downregulation of E2F4. Taken together, our data provide the first clinically relevant in vitro model to support cellular adhesion and downregulation of TGFB2 as a potential mechanism by which PCa cells may escape from dormancy. Targeting the TGF-beta2-associated mechanism could provide novel opportunities to prevent lethal PCa metastasis. PMID:26090669

  16. Cellular Adhesion Promotes Prostate Cancer Cells Escape from Dormancy.

    PubMed

    Ruppender, Nazanin; Larson, Sandy; Lakely, Bryce; Kollath, Lori; Brown, Lisha; Coleman, Ilsa; Coleman, Roger; Nguyen, Holly; Nelson, Peter S; Corey, Eva; Snyder, Linda A; Vessella, Robert L; Morrissey, Colm; Lam, Hung-Ming

    2015-01-01

    Dissemination of prostate cancer (PCa) cells to the bone marrow is an early event in the disease process. In some patients, disseminated tumor cells (DTC) proliferate to form active metastases after a prolonged period of undetectable disease known as tumor dormancy. Identifying mechanisms of PCa dormancy and reactivation remain a challenge partly due to the lack of in vitro models. Here, we characterized in vitro PCa dormancy-reactivation by inducing cells from three patient-derived xenograft (PDX) lines to proliferate through tumor cell contact with each other and with bone marrow stroma. Proliferating PCa cells demonstrated tumor cell-cell contact and integrin clustering by immunofluorescence. Global gene expression analyses on proliferating cells cultured on bone marrow stroma revealed a downregulation of TGFB2 in all of the three proliferating PCa PDX lines when compared to their non-proliferating counterparts. Furthermore, constitutive activation of myosin light chain kinase (MLCK), a downstream effector of integrin-beta1 and TGF-beta2, in non-proliferating cells promoted cell proliferation. This cell proliferation was associated with an upregulation of CDK6 and a downregulation of E2F4. Taken together, our data provide the first clinically relevant in vitro model to support cellular adhesion and downregulation of TGFB2 as a potential mechanism by which PCa cells may escape from dormancy. Targeting the TGF-beta2-associated mechanism could provide novel opportunities to prevent lethal PCa metastasis. PMID:26090669

  17. Wheat ABA-insensitive mutants result in reduced grain dormancy

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This paper describes the isolation of wheat mutants in the hard red spring Scarlet resulting in reduced sensitivity to the plant hormone abscisic acid (ABA) during seed germination. ABA induces seed dormancy during embryo maturation and inhibits the germination of mature seeds. Wheat sensitivity t...

  18. Breaking seed dormancy of switchgrass (Panicum virgatum L.): A review

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Switchgrass (Panicum virgatum L.) is a perennial warm-season grass identified as a model species for bioenergy feedstock. Established switchgrass stand are very resilient to environmental fluctuations, however, seed dormancy and weak seedling vigor make establishment difficult. Seeds with high leve...

  19. Seed Dormancy in Weedy Rice (Oryza sativa L.)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Seed dormancy has been associated with grain color in wheat and rice, with the red colored genotypes being more dormant than the white colored ones. However, it remains uncertain if the association arises from pleiotropy or linkage. We introduced a segment of chromosome harboring a cluster of quanti...

  20. Perspectives of biotechnologies based on dormancy phenomenon for space researches

    NASA Astrophysics Data System (ADS)

    Alekseev, V.; Sychev, V.; Layus, D.; Levinsky, M.; Novikova, N.; Zakhodnova, T.

    Long term space missions will require a renewable source of food and an efficient method to recycle oxygen Plants especially aquatic micro algae provide an obvious solution to these problems However long duration plant growth and reproduction in space that is necessary for transportation of a control ecological life support system CELSS from Earth to other planets are problematic The introduction of heterotrophs in space CELSS is a more formidable problem as the absence of gravity creates additional difficulties for their life Dormancy phenomenon protected a great many animals and plants in harsh environmental conditions within a special resting phases of life cycle lasting from months up to hundred years This phenomenon can be quite perspective as a tool to overcome difficulties with CELSS transportation in space missions Cryptobiotic stages of microbes fungi unicellular algae and protists can survive in open space conditions that is important for interplanetary quarantine and biological security inside spacecraft Searching for life outside the Earth at such planet like Mars with extremely variable environment should be oriented on dormancy as crucial phases of a life cycle in such organisms Five major research programs aimed on study dormancy phenomenon for exobiology purposes and creation of new biotechnologies are discussed List of species candidate components of CELSS with dormancy in their life cycle used in space experiments at the Russian segment of International Space Station now includes 26 species from bacteria to fish The

  1. Supercooling in overwintering azalea flower buds.

    PubMed

    George, M F; Burke, M J; Weiser, C J

    1974-07-01

    Differential thermal analysis and nuclear magnetic resonance spectroscopy experiments on whole flower buds and excised floral primordia of azalea (Rhododendron kosterianum, Schneid.) proved that supercooling is the mode of freezing resistance (avoidance) of azalea flower primordia. Increase in the linewidth of nuclear magnetic resonance spectra for water upon thawing supports the view that injury to the primordia occurs at the moment of freezing. Nonliving primordia freeze at the same temperatures as living primordia, indicating that morphological features of primordial tissues are a key factor in freezing avoidance of dormant azalea flower primordia. Differential thermal analyses was used to study the relationship of cooling rate to the freezing points of floral primordia in whole flower buds. At a cooling rate of 8.5 C per hour, primordia in whole buds froze at about the same subfreezing temperatures as did excised primordia cooled at 37 C per hour. At more rapid cooling rates primordia in intact buds froze at higher temperatures. PMID:16658832

  2. Supercooling in Overwintering Azalea Flower Buds 1

    PubMed Central

    George, Milon F.; Burke, Michael J.; Weiser, Conrad J.

    1974-01-01

    Differential thermal analysis and nuclear magnetic resonance spectroscopy experiments on whole flower buds and excised floral primordia of azalea (Rhododendron kosterianum, Schneid.) proved that supercooling is the mode of freezing resistance (avoidance) of azalea flower primordia. Increase in the linewidth of nuclear magnetic resonance spectra for water upon thawing supports the view that injury to the primordia occurs at the moment of freezing. Nonliving primordia freeze at the same temperatures as living primordia, indicating that morphological features of primordial tissues are a key factor in freezing avoidance of dormant azalea flower primordia. Differential thermal analyses was used to study the relationship of cooling rate to the freezing points of floral primordia in whole flower buds. At a cooling rate of 8.5 C per hour, primordia in whole buds froze at about the same subfreezing temperatures as did excised primordia cooled at 37 C per hour. At more rapid cooling rates primordia in intact buds froze at higher temperatures. PMID:16658832

  3. 30 CFR 57.4560 - Mine entrances.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Mine entrances. 57.4560 Section 57.4560 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Fire Prevention and...

  4. 30 CFR 57.4560 - Mine entrances.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Mine entrances. 57.4560 Section 57.4560 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Fire Prevention and...

  5. 30 CFR 57.4560 - Mine entrances.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Mine entrances. 57.4560 Section 57.4560 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Fire Prevention and...

  6. Korean College Entrance Exams: An Inside Look

    ERIC Educational Resources Information Center

    Hong, Dae S.; Choi, Kyong Mi

    2011-01-01

    Mathematics educators are intensely interested in how mathematics is taught and learned in other countries. In Korea, for instance, the college entrance examination has played a major role in shaping Korean mathematics education (Kwon 2006). All high school students who want to pursue a college degree are required to take a college entrance…

  7. Budded baculovirus particle structure revisited.

    PubMed

    Wang, Qiushi; Bosch, Berend-Jan; Vlak, Just M; van Oers, Monique M; Rottier, Peter J; van Lent, Jan W M

    2016-02-01

    Baculoviruses are a group of enveloped, double-stranded DNA insect viruses with budded (BV) and occlusion-derived (ODV) virions produced during their infection cycle. BVs are commonly described as rod shaped particles with a high apical density of protein extensions (spikes) on the lipid envelope surface. However, due to the fragility of BVs the conventional purification and electron microscopy (EM) staining methods considerably distort the native viral structure. Here, we use cryo-EM analysis to reveal the near-native morphology of two intensively studied baculoviruses, Autographa californica multicapsid nucleopolyhedrovirus (AcMNPV) and Spodoptera exigua MNPV (SeMNPV), as models for BVs carrying GP64 and F as envelope fusion protein on the surface. The now well-preserved AcMNPV and SeMNPV BV particles have a remarkable elongated, ovoid shape leaving a large, lateral space between nucleocapsid (NC) and envelope. Consistent with previous findings the NC has a distinctive cap and base structure interacting tightly with the envelope. This tight interaction may explain the partial retaining of the envelope on both ends of the NC and the disappearance of the remainder of the BV envelope in the negative-staining EM images. Cryo-EM also reveals that the viral envelope contains two layers with a total thickness of ?6-7nm, which is significantly thicker than a usual biological membrane (<4nm) as measured by X-ray scanning. Most spikes are densely clustered at the two apical ends of the virion although some envelope proteins are also found more sparsely on the lateral regions. The spikes on the surface of AcMNPV BVs appear distinctly different from those of SeMNPV. Based on our observations we propose a new near-native structural model of baculovirus BVs. PMID:26743500

  8. Phylogeny of seed dormancy in Convolvulaceae, subfamily Convolvuloideae (Solanales)

    PubMed Central

    Jayasuriya, K. M. G. Gehan; Baskin, Jerry M.; Geneve, Robert L.; Baskin, Carol C.

    2009-01-01

    Background and Aims The water gap is an important morphoanatomical structure in seeds with physical dormancy (PY). It is an environmental signal detector for dormancy break and the route of water into the non-dormant seed. The Convolvulaceae, which consists of subfamilies Convolvuloideae (11 tribes) and Humbertoideae (one tribe, monotypic Humberteae), is the only family in the asterid clade known to produce seeds with PY. The primary aim of this study was to compare the morphoanatomical characteristics of the water gap in seeds of species in the 11 tribes of the Convolvuloideae and to use this information, and that on seed dormancy and storage behaviour, to construct a phylogenetic tree of seed dormancy for the subfamily. Methods Scanning electron microscopy (SEM) was used to define morphological changes in the hilum area during dormancy break; hand and vibratome sections were taken to describe the anatomy of the water gap, hilum and seed coat; and dye tracking was used to identify the initial route of water entry into the non-dormant seed. Results were compared with a recent cladogram of the family. Key Results Species in nine tribes have (a) layer(s) of palisade cells in the seed coat, a water gap and orthodox storage behaviour. Erycibe (Erycibeae) and Maripa (Maripeae) do not have a palisade layer in the seed coat or a water gap, and are recalcitrant. The hilar fissure is the water gap in relatively basal Cuscuteae, and bulges adjacent to the micropyle serve as the water gap in the Convolvuloideae, Dicranostyloideae (except Maripeae) and the Cardiochlamyeae clades. Seeds from the Convolvuloideae have morphologically prominent bulges demarcated by cell shape in the sclereid layer, whereas the Dicranostyloideae and Cardiochlamyeae have non-prominent bulges demarcated by the number of sub-cell layers. The anatomy and morphology of the hilar pad follow the same pattern. Conclusions PY in the subfamily Convolvuloideae probably evolved in the aseasonal tropics from an ancestor with recalcitrant non-dormant seeds, and it may have arisen as Convolvulaceae radiated to occupy the seasonal tropics. Combinational dormancy may have developed in seeds of some Cuscuta spp. as this genus moved into temperate habitats. PMID:19074450

  9. Shrinkage of ipsilateral taste buds and hyperplasia of contralateral taste buds following chorda tympani nerve transection

    PubMed Central

    Li, Yi-ke; Yang, Juan-mei; Huang, Yi-bo; Ren, Dong-dong; Chi, Fang-lu

    2015-01-01

    The morphological changes that occur in the taste buds after denervation are not well understood in rats, especially in the contralateral tongue epithelium. In this study, we investigated the time course of morphological changes in the taste buds following unilateral nerve transection. The role of the trigeminal component of the lingual nerve in maintaining the structural integrity of the taste buds was also examined. Twenty-four Sprague-Dawley rats were randomly divided into three groups: control, unilateral chorda tympani nerve transection and unilateral chorda tympani nerve transection + lingual nerve transection. Rats were allowed up to 42 days of recovery before being euthanized. The taste buds were visualized using a cytokeratin 8 antibody. Taste bud counts, volumes and taste receptor cell numbers were quantified and compared among groups. No significant difference was detected between the chorda tympani nerve transection and chorda tympani nerve transection + lingual nerve transection groups. Taste bud counts, volumes and taste receptor cell numbers on the ipsilateral side all decreased significantly compared with control. On the contralateral side, the number of taste buds remained unchanged over time, but they were larger, and taste receptor cells were more numerous postoperatively. There was no evidence for a role of the trigeminal branch of the lingual nerve in maintaining the structural integrity of the anterior taste buds. PMID:26199619

  10. 43. INTERIOR, FIRST FLOOR, ENTRANCE HALL, VIEW TO NORTH WALL ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    43. INTERIOR, FIRST FLOOR, ENTRANCE HALL, VIEW TO NORTH WALL AND EAST (FRONT) ENTRANCE DOOR FROM THE SOUTHWEST - Mark Twain House, 351 Farmington Avenue (corrected from original address of 531 Farmington Avenue), Hartford, Hartford County, CT

  11. 3. NORTH SIDE SHOWING GABLED PORCH COVERING ON NORTH ENTRANCE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    3. NORTH SIDE SHOWING GABLED PORCH COVERING ON NORTH ENTRANCE AND SHED PORCH COVERING ON EAST ENTRANCE. VIEW TO SOUTHWEST. - Bishop Creek Hydroelectric System, Control Station, Hydrographer's Office, Bishop Creek, Bishop, Inyo County, CA

  12. 6. DETAIL VIEW OF ENTRANCE GATES, SHOWING IRON GATE, STONE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    6. DETAIL VIEW OF ENTRANCE GATES, SHOWING IRON GATE, STONE WORK, AND GATE STOP FROM SOUTHEAST OF NORTHWEST ELEMENTS. - William Enston Home, Entrance Gate, 900 King Street, Charleston, Charleston County, SC

  13. 4. Light tower, interior from entrance, looking southeast Goat ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. Light tower, interior from entrance, looking southeast - Goat Island Light Station, Goat Island, next to entrance to Cape Porpoise Harbor, just south of Trott Island, Cape Porpoise, York County, ME

  14. 57. POWDER MAGAZINE, DETAIL VIEW OF NORTHEAST FRONT ENTRANCE TO ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    57. POWDER MAGAZINE, DETAIL VIEW OF NORTHEAST FRONT ENTRANCE TO ACESS PASSAGE TO MAGAZINES FROM INTERIOR OF MAGAZINE SHOWING VENTILATION WINDOWS (BARRED) FLANKING ENTRANCE DOOR (OPEN). NOTE ACCESS PASSAGE TO ADJOING MAGAZINE. - Fort Monroe, Fortress, Hampton, Hampton, VA

  15. 28. ROAD VIEW OF HIGHWAY 267 SOUTH OF GRAPEVINE ENTRANCE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    28. ROAD VIEW OF HIGHWAY 267 SOUTH OF GRAPEVINE ENTRANCE STATION. NOTE ENTRANCE STATION IN DISTANCE. LOOKING NW. (SAME AS CA-300-7.) - Death Valley National Park Roads, Death Valley Junction, Inyo County, CA

  16. A local dormancy cline is related to the seed maturation environment, population genetic composition and climate

    PubMed Central

    Fernández-Pascual, Eduardo; Jiménez-Alfaro, Borja; Caujapé-Castells, Juli; Jaén-Molina, Ruth; Díaz, Tomás Emilio

    2013-01-01

    Background and Aims Seed dormancy varies within species in response to climate, both in the long term (through ecotypes or clines) and in the short term (through the influence of the seed maturation environment). Disentangling both processes is crucial to understand plant adaptation to environmental changes. In this study, the local patterns of seed dormancy were investigated in a narrow endemic species, Centaurium somedanum, in order to determine the influence of the seed maturation environment, population genetic composition and climate. Methods Laboratory germination experiments were performed to measure dormancy in (1) seeds collected from different wild populations along a local altitudinal gradient and (2) seeds of a subsequent generation produced in a common garden. The genetic composition of the original populations was characterized using intersimple sequence repeat (ISSR) PCR and principal co-ordinate analysis (PCoA), and its correlation with the dormancy patterns of both generations was analysed. The effect of the local climate on dormancy was also modelled. Key Results An altitudinal dormancy cline was found in the wild populations, which was maintained by the plants grown in the common garden. However, seeds from the common garden responded better to stratification, and their release from dormancy was more intense. The patterns of dormancy variation were correlated with genetic composition, whereas lower temperature and summer precipitation at the population sites predicted higher dormancy in the seeds of both generations. Conclusions The dormancy cline in C. somedanum is related to a local climatic gradient and also corresponds to genetic differentiation among populations. This cline is further affected by the weather conditions during seed maturation, which influence the receptiveness to dormancy-breaking factors. These results show that dormancy is influenced by both long-and short-term climatic variation. Such processes at such a reduced spatial scale highlight the potential of plants to adapt to fast environmental changes. PMID:23864001

  17. Entrance channel cluster folding potentials for knockout reactions

    SciTech Connect

    Jain, Arun K.; Joshi, B. N.

    2008-02-15

    The entrance channel optical potentials for ({alpha},2{alpha}) reactions are calculated using single folding models. These are found to be much different from the conventional entrance channel potentials and use of these folded entrance channel optical potentials significantly change the absolute cross sections. Small reductions in the entrance channel potentials are found to increase the peak to dip cross section ratios drastically for the knockout of {alpha}-clusters bound in the l=1 state.

  18. Mechanisms of disseminated cancer cell dormancy: an awakening field

    PubMed Central

    Sosa, María Soledad; Bragado, Paloma; Aguirre-Ghiso, Julio A.

    2014-01-01

    Metastases arise from residual disseminated tumour cells (DTCs). This can happen years after primary tumour treatment because residual tumour cells can enter dormancy and evade therapies. As the biology of minimal residual disease seems to diverge from that of proliferative lesions, understanding the underpinnings of this new cancer biology is key to prevent metastasis. Analysis of approximately 7 years of literature reveals a growing focus on tumour and normal stem cell quiescence, extracellular and stromal microenvironments, autophagy and epigenetics as mechanisms that dictate tumour cell dormancy. In this Review, we attempt to integrate this information and highlight both the weaknesses and the strengths in the field to provide a framework to understand and target this crucial step in cancer progression. PMID:25118602

  19. Dormancy and Recovery Testing for Biological Wastewater Processors

    NASA Technical Reports Server (NTRS)

    Hummerick, Mary E.; Coutts, Janelle L.; Lunn, Griffin M.; Spencer, LaShelle; Khodadad, Christina L.; Frances, Someliz; Wheller, Raymond

    2015-01-01

    Bioreactors, such as aerated membrane type bioreactors have been proposed and studied for a number of years as an alternate approach for treating wastewater streams for space exploration. Several challenges remain before these types of bioreactors can be used in space settings, including transporting the bioreactors with their microbial communities to space, whether that be the International Space Station or beyond, or procedures for safing the systems and placing them into dormant state for later start-up. Little information is available on such operations as it is not common practice for terrestrial systems. This study explored several dormancy processes for established bioreactors to determine optimal storage and recovery conditions. Procedures focused on complete isolation of the microbial communities from an operational standpoint and observing the effects of: 1) storage temperature, and 2) storage with or without the reactor bulk fluid. The first consideration was tested from a microbial integrity and power consumption standpoint; both room temperature (25 C) and cold (4 C) storage conditions were studied. The second consideration was explored; again, for microbial integrity as well as plausible real-world scenarios of how terrestrially established bioreactors would be transported to microgravity and stored for periods of time between operations. Biofilms were stored without the reactor bulk fluid to simulate transport of established biofilms into microgravity, while biofilms stored with the reactor bulk fluid simulated the most simplistic storage condition to implement operations for extended periods of nonuse. Dormancy condition did not have an influence on recovery in initial studies with immature biofilms (48 days old), however, a lengthy recovery time was required (20+ days). Bioreactors with fully established biofilms (13 months) were able to recover from a 7-month dormancy period to steady state operation within 4 days (approximately 1 residence cycle). Results indicate a need for future testing on biofilm age and health and further exploration of dormancy length.

  20. Dormancy and Recovery Testing for Biological Wastewater Processors

    NASA Technical Reports Server (NTRS)

    Hummerick, Mary E.; Coutts, Janelle L.; Lunn, Griffin M.; Spencer, LaShelle; Khodadad, Christina L.; Birmele, Michele N.; Frances, Someliz; Wheeler, Raymond

    2015-01-01

    Bioreactors, such as the aerated hollow fiber membrane type, have been proposed and studied for a number of years as an alternate approach for treating wastewater streams for space exploration. Several challenges remain to be resolved before these types of bioreactors can be used in space settings, including transporting the bioreactors with intact and active biofilms, whether that be to the International Space Station or beyond, or procedures for safing the systems and placing them into a dormant state for later start-up. Little information is available on such operations as it is not common practice for terrestrial systems. This study explored several dormancy processes for established bioreactors to determine optimal storage and recovery conditions. Procedures focused on complete isolation of the microbial communities from an operational standpoint and observing the effects of: 1) storage temperature, and 2) storage with or without the reactor bulk fluid. The first consideration was tested from a microbial integrity and power consumption standpoint; both ambient temperature (25 C) and cold (4 C) storage conditions were studied. The second consideration was explored; again, for microbial integrity as well as plausible real-world scenarios of how terrestrially established bioreactors would be transported to microgravity and stored for periods of time between operations. Biofilms were stored without the reactor bulk fluid to simulate transport of established biofilms into microgravity, while biofilms stored with the reactor bulk fluid simulated the most simplistic storage condition to implement operations for extended periods of nonuse. Dormancy condition did not have an influence on recovery in initial studies with immature biofilms (48 days old), however a lengthy recovery time was required (20+ days). Bioreactors with fully established biofilms (13 months) were able to recover from a 7-month dormancy period to steady state operation within 4 days (approx. 1 residence cycle). Results indicate a need for future testing on biofilm age and health and further exploration of dormancy length.

  1. 81. EXTERIOR VIEW, EAST SIDE, SHOWING ENTRANCE TO BOILER ROOM ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    81. EXTERIOR VIEW, EAST SIDE, SHOWING ENTRANCE TO BOILER ROOM ON LEFT, ENTRANCE TO STABLES AT CENTER, AND ENTRANCE TO ENGINE ROOM ON RIGHT. - Gruber Wagon Works, Pennsylvania Route 183 & State Hill Road at Red Bridge Park, Bernville, Berks County, PA

  2. Profile of State College Entrance Exam Policies. Idaho

    ERIC Educational Resources Information Center

    Center on Education Policy, 2011

    2011-01-01

    This individual profile provides information on Idaho's college entrance exam standards and polices. Some of the categories presented include: (1) College entrance exam policy; (2) Purpose; (3) Major changes in college entrance exam policy since the 2009-10 school year for financial reasons; (4) Preparation state offers to students taking college…

  3. Profile of State College Entrance Exam Policies. Alabama

    ERIC Educational Resources Information Center

    Center on Education Policy, 2011

    2011-01-01

    This individual profile provides information on Alabama's college entrance exam standards and polices. Some of the categories presented include: (1) College entrance exam policy; (2) Purpose; (3) Major changes in college entrance exam policy since the 2009-10 school year for financial reasons; (4) Preparation state offers to students taking…

  4. Profile of State College Entrance Exam Policies. Delaware

    ERIC Educational Resources Information Center

    Center on Education Policy, 2011

    2011-01-01

    This individual profile provides information on Delaware's college entrance exam standards and polices. Some of the categories presented include: (1) College entrance exam policy; (2) Purpose; (3) Major changes in college entrance exam policy since the 2009-10 school year for financial reasons; (4) Preparation state offers to students taking…

  5. Profile of State College Entrance Exam Policies. North Dakota

    ERIC Educational Resources Information Center

    Center on Education Policy, 2011

    2011-01-01

    This individual profile provides information on North Dakota's college entrance exam standards and polices. Some of the categories presented include: (1) College entrance exam policy; (2) Purpose; (3) Major changes in college entrance exam policy since the 2009-10 school year for financial reasons; (4) Preparation state offers to students taking…

  6. Profile of State College Entrance Exam Policies. Maine

    ERIC Educational Resources Information Center

    Center on Education Policy, 2011

    2011-01-01

    This individual profile provides information on Maine's college entrance exam standards and polices. Some of the categories presented include: (1) College entrance exam policy; (2) Purpose; (3) Major changes in college entrance exam policy since the 2009-10 school year for financial reasons; (4) Preparation state offers to students taking college…

  7. Profile of State College Entrance Exam Policies. Kentucky

    ERIC Educational Resources Information Center

    Center on Education Policy, 2011

    2011-01-01

    This individual profile provides information on Kentucky's college entrance exam standards and polices. Some of the categories presented include: (1) College entrance exam policy; (2) Purpose; (3) Major changes in college entrance exam policy since the 2009-10 school year for financial reasons; (4) Preparation state offers to students taking…

  8. Profile of State College Entrance Exam Policies. Tennessee

    ERIC Educational Resources Information Center

    Center on Education Policy, 2011

    2011-01-01

    This individual profile provides information on Tennessee's college entrance exam standards and polices. Some of the categories presented include: (1) College entrance exam policy; (2) Purpose; (3) Major changes in college entrance exam policy since the 2009-10 school year for financial reasons; (4) Preparation state offers to students taking…

  9. Reproductive dormancy in boll-weevil from populations of the midwest of Brazil.

    PubMed

    Paula, D P; Claudino, D; Timbó, R V; Miranda, J E; Bemquerer, M P; Ribeiro, A C J; Sujii, E R; Fontes, E M G; Pires, C S S

    2013-02-01

    The boll weevil (Anthonomus grandis Boheman) (Coleoptera: Curculionidae) is an introduced pest in Brazil, which in 30 yr has successfully expanded to various eco-regions and became the most important pest of cotton (Gossypium hirsutum, Malvaceae). Given the limited knowledge about the adaptive mechanisms that allowed successful establishment of the pest population in a tropical region, in this work we studied the potential of the Midwest population of boll weevils to enter a reproductive dormancy and identified the importance of the feeding source for induction of dormancy. We investigated morphological and physiological characters as indicators of the dormancy. We also investigated the occurrence of reproductive dormancy in boll weevils populations from cotton farms of the Midwestern region of Brazil during the cotton and noncotton seasons of 2009 and 2010. The studies revealed that boll weevils entered facultative reproductive dormancy; however, unlike what has been observed for boll weevils from temperate and subtropical regions, the hypertrophy of fat body and hexamerin levels did not straightly correlated to reproductive dormancy. The food source and field conditions during early adult development were decisive factor for the induction of reproductive dormancy. The incidence of reproductive dormancy increased progressively as the phenology of cotton plant advanced, reaching approximately 90% at the end of the crop season. During the noncotton season, the boll weevil was predominantly found in reproductive dormancy, especially females; however, there is evidence of use of multiple adaptive strategies to colonize the next harvest. PMID:23448019

  10. Local climate explains degree of seed dormancy in Hypericum elodes L. (Hypericaceae).

    PubMed

    Carta, A; Probert, R; Puglia, G; Peruzzi, L; Bedini, G

    2016-01-01

    Seed dormancy and germination characteristics may vary within species in response to several factors. Knowledge of such variation is crucial to understand plant evolution and adaptation to environmental changes. We examined the correlation of climate and population genetic differentiation (ISSR) with primary seed dormancy and germination behaviour in populations of the Atlantic-European soft-water pool specialist Hypericum elodes. Primary dormancy was measured by analysing seed germination response of fresh seeds and after various periods of cold stratification. Laboratory germination experiments revealed that the single most important factor for promoting germination was cold stratification prior to placing at the germination temperature. However, in agreement with their weaker primary dormancy, the seeds germinated well when fresh, and the benefit of cold stratification was more relaxed for the southern populations. Seeds of all populations demonstrated a near absolute requirement for a light and alternating temperature regime in order to germinate. The promoting effect of alternating temperatures was particularly effective at warm temperatures (mean 20 °C) but not at cool temperatures. Whilst seed germination requirements were similar among populations, the degree of primary dormancy varied considerably and was not associated with population genetic differentiation. Primary dormancy degree was instead associated with local climate: higher temperature in summer and rainfall in winter predicted weak and rapid loss of dormancy. These results suggest that seed maturation environment may play a substantial role in explaining the degree of dormancy in H. elodes, highlighting that physiological dormancy can be modulated by local climate. PMID:25662792

  11. Dehydration and vernalization treatments identify overlapping molecular networks impacting endodormancy maintenance in leafy spurge crown buds.

    PubMed

    Doğramacı, Münevver; Horvath, David P; Christoffers, Michael J; Anderson, James V

    2011-12-01

    Leafy spurge (Euphorbia esula L.) is a herbaceous perennial weed that reproduces vegetatively from an abundance of underground adventitious buds (UABs), which undergo well-defined phases of seasonal dormancy (para-, endo-, and ecodormancy). In this study, the effects of dehydration stress on vegetative growth and flowering potential from endodormant UABs of leafy spurge was monitored. Further, microarray analysis was used to identify critical signaling pathways of transcriptome profiles associated with endodormancy maintenance in UABs. Surprisingly, only 3-day of dehydration stress is required to break the endodormant phase in UABs; however, the dehydration-stress treatment did not induce flowering. Previous studies have shown that prolonged cold treatment of UABs breaks endodormancy and induces a vernalization response leading to flowering. Thus, in this study, comparing transcriptome data from UABs exposed to short-term dehydration and vernalization provided a unique approach to identify overlapping molecular mechanisms involved in endodormancy maintenance and floral competence. Analysis of transcriptome data associated with breaking endodormancy by both environmental treatments identified LEC1, PHOTOSYSTEM I RC, and brassinosteroids as common central hubs of upregulated genes, while DREB1A, CBF2, GPA1, MYC2, bHLH, BZIP, and flavonoids were identified as common central hubs of downregulated genes. The majority of over-represented gene sets common to breaking endodormancy by dehydration stress and vernalization were downregulated and included pathways involved in hormone signaling, chromatin modification, and circadian rhythm. Additionally, the over-represented gene sets highlighted pathways involved in starch and sugar degradation and biogenesis of carbon skeletons, suggesting a high metabolic activity is necessary during the endodormant phase. The data presented in this study helped to refine our previous model for dormancy regulation. PMID:21789635

  12. Phenotypic Diversity as a Mechanism to Exit Cellular Dormancy

    PubMed Central

    Sturm, Alexander; Dworkin, Jonathan

    2016-01-01

    SUMMARY Microorganisms can facilitate their survival in stressful environments by entering a state of metabolic inactivity or dormancy [1]. However, this state impairs the function of the very sensory systems necessary to detect favorable growth conditions. Thus, how can a metabolically quiescent cell accurately monitor environmental conditions in order to best decide when to exit dormancy? One strategy employed by microbes to deal with changing environments is the generation of phenotypes that may be less well adapted to a current condition but might confer an advantage in the future [2, 3]. This bet-hedging depends on phenotypic diversity in the population [4], which itself can derive from naturally occurring stochastic differences in gene expression [5, 6]. In the case of metabolic dormancy, a bet-hedging strategy that has been proposed is the “scout model” where cells comprising a fraction of the dormant population reinitiate growth stochastically, independent of environmental cues [7, 8]. Here, we provide experimental evidence that such a mechanism exists in dormant spores produced by the ubiquitous soil bacterium Bacillus subtilis. We observe that these spores reinitiate growth at a low but measureable frequency even in the absence of an inducing signal. This phenomenon is the result of phenotypic variation in the propensity of individual spores to reinitiate growth spontaneously. Since this bet-hedging mechanism produces individuals that will either grow under favorable conditions or die under unfavorable conditions, a population can properly respond to environmental changes despite the impaired sensory ability of individual cells. PMID:26279233

  13. Dormancy cues alter insect temperature-size relationships.

    PubMed

    Clemmensen, Sharon F; Hahn, Daniel A

    2015-01-01

    Developmental temperatures can have dramatic effects on body size in ectotherms. Thermal plasticity in body size is often viewed in the context of seasonality, but the role of seasonal dormancy responses in generating temperature-size relationships is underappreciated. We used the moth Helicoverpa zea (corn earworm) to examine how photoperiodic seasonal dormancy programming for pupal diapause affects the temperature-size relationship. Specifically, we partition out the contributions of somatic growth versus nutrient storage as fat to the thermal reaction norm for size. With increasing temperature from 16 °C to 20 °C, dormant pupae were both overall larger and progressively fatter than non-dormant pupae. This body mass response is likely driven by concurrent increases in food consumption and longer development times as temperatures increase. Our results demonstrate that seasonal photoperiodic cues can alter temperature-size relationships during pre-dormancy development. For biologists interested in seasonal effects on temperature-size relationships, our results suggest that the key to fully understanding these relationships may lie in integrating multiple seasonal cues and multiple aspects of body size and composition in a nutrient-allocation framework. PMID:25260999

  14. Seed dormancy and ABA signaling: the breakthrough goes on.

    PubMed

    Rodríguez-Gacio, María del Carmen; Matilla-Vázquez, Miguel A; Matilla, Angel J

    2009-11-01

    The seed is an important organ of higher plants regarding plant survival and species dispersion. The transition between seed dormancy and germination represents a critical stage in the plant life cycle and it is an important ecological and commercial trait. A dynamic balance of synthesis and catabolism of two antagonistic hormones, abscisic acid (ABA) and giberellins (GAs), controls the equilibrium between seed dormancy and germination. Embryonic ABA plays a central role in induction and maintenance of seed dormancy, and also inhibits the transition from embryonic to germination growth. Therefore, the ABA metabolism must be highly regulated at both temporal and spatial levels during phase of dessication tolerance. On the other hand, the ABA levels do not depend exclusively on the seeds because sometimes it becomes a strong sink and imports it from the roots and rhizosphere through the xylem and/or phloem. All theses events are discussed in depth here. Likewise, the role of some recently characterized genes belonging to seeds of woody species and related to ABA signaling, are also included. Finally, although four possible ABA receptors have been reported, not much is known about how they mediate ABA signalling transduction. However, new publications seem to shown that almost all these receptors lack several properties to consider them as such. PMID:19875942

  15. Phenotypic Diversity as a Mechanism to Exit Cellular Dormancy.

    PubMed

    Sturm, Alexander; Dworkin, Jonathan

    2015-08-31

    Microorganisms can facilitate their survival in stressful environments by entering a state of metabolic inactivity or dormancy. However, this state impairs the function of the very sensory systems necessary to detect favorable growth conditions. Thus, how can a metabolically quiescent cell accurately monitor environmental conditions in order to best decide when to exit dormancy? One strategy employed by microbes to deal with changing environments is the generation of phenotypes that may be less well adapted to a current condition but might confer an advantage in the future. This bet-hedging depends on phenotypic diversity in the population, which itself can derive from naturally occurring stochastic differences in gene expression. In the case of metabolic dormancy, a bet-hedging strategy that has been proposed is the "scout model" where cells comprising a fraction of the dormant population reinitiate growth stochastically, independent of environmental cues. Here, we provide experimental evidence that such a mechanism exists in dormant spores produced by the ubiquitous soil bacterium Bacillus subtilis. We observe that these spores reinitiate growth at a low but measureable frequency even in the absence of an inducing signal. This phenomenon is the result of phenotypic variation in the propensity of individual spores to reinitiate growth spontaneously. Since this bet-hedging mechanism produces individuals that will either grow under favorable conditions or die under unfavorable conditions, a population can properly respond to environmental changes despite the impaired sensory ability of individual cells. PMID:26279233

  16. Physical Dormancy in Seeds of the Holoparasitic Angiosperm Cuscuta australis (Convolvulaceae, Cuscuteae): Dormancy-breaking Requirements, Anatomy of the Water Gap and Sensitivity Cycling

    PubMed Central

    Jayasuriya, K. M. G. Gehan; Baskin, Jerry M.; Geneve, Robert L.; Baskin, Carol C.; Chien, Ching-Te

    2008-01-01

    Background and Aims Dormancy in seeds of Cuscuta (Convolvulaceae, tribe Cuscuteae) is due to a water-impermeable seed coat (physical dormancy). In nondormant seeds of several species of this family, bulges adjacent to the micropyle have been identified as the initial route of water entry into seeds (water gap). However, there are claims that water enters seeds of Cuscuta spp. via the entire seed coat. Although several studies have been done on seed coat anatomy of Cuscuta, none has identified and/or characterized the morphology/anatomy of a water gap. Thus, the primary aim of this research was to identify and describe the morphology and anatomy of the water gap in seeds of Cuscuta australis. It was also determined if sensitivity cycling to dormancy-breaking treatments occurs in seeds of this species. Methods Light microscopy, scanning electron microscopy, tissue-sectioning and dye-tracking and blocking experiments were used to investigate the morphology and anatomy of the water gap. Treatments simulating natural conditions were used to break seed dormancy. Storage of seeds at different temperatures was tested for their effect on sensitivity to dormancy-breaking treatment. Key Results Dormancy-breaking treatments caused the tightly closed hilar fissure to open. Staining was observed in cells below the hilum area but not in those below the seed coat away from the hilum. Sensitivity to dormancy-breaking treatment was induced by storing seeds dry and reduced by storing them wet. Conclusions Whereas bulges adjacent to the micropyle act as the water gap in other species of Convolvulaceae with physical dormancy, the hilar fissure serves this function in Cuscuta. Cuscuta australis can cycle between insensitivity ↔ sensitivity to dormancy-breaking treatments. PMID:18453546

  17. Ecotypic variation of summer dormancy relaxation associated with rainfall gradient in the geophytic grass Poa bulbosa

    PubMed Central

    Ofir, Micha; Kigel, Jaime

    2010-01-01

    Background and Aims Summer dormancy is an adaptive trait in geophytes inhabiting regions with a Mediterranean climate, allowing their survival through the hot and dry summers. Summer dormancy in Poa bulbosa is induced by increasing day-length and temperature and decreasing water availability during spring. Populations from arid habitats became dormant earlier than those from mesic habitats. Relaxation of dormancy was promoted by the hot, dry summer conditions. Here we test the hypothesis that dormancy relaxation is also delayed in ecotypes of P. bulbosa inhabiting arid regions, as a cautious strategy related to the greater unpredictability of autumn rains associated with decreasing precipitation. Methods Ecotypes collected across a precipitation gradient (100–1200 mm year−1) in the Mediterranean climate region were grown under similar conditions in a net-house in Israel. Differences among ecotypes in dormancy induction and dormancy relaxation were determined by measuring time to dormancy onset in spring, and time to sprouting after the first effective rain in autumn. Seasonal and ecotype variation in dormancy relaxation were assessed by measuring time to sprouting initiation, rate of sprouting and maximal sprouting of resting dry bulbs sampled in the net-house during late spring, and mid- and late summer, and planted in a wet substrate at temperatures promoting (10 °C) or limiting (20 °C) sprouting. Key Results Earlier dormancy in the spring and delayed sprouting in autumn were correlated with decreasing mean annual rainfall at the site of ecotype origin. Seasonal and ecotype differences in dormancy relaxation were expressed in bulbs planted at 20 °C. During the summer, time to sprouting decreased while rate of sprouting and maximal sprouting increased, indicating dormancy relaxation. Ecotypes from more arid sites across the rainfall gradient showed delayed onset of sprouting and lower maximal sprouting, but did not differ in rate of sprouting. Planting at 10 °C promoted sprouting and cancelled differences among ecotypes in dormancy relaxation. Conclusions Both the induction and the relaxation of summer dormancy in P. bulbosa are correlated with mean annual precipitation at the site of population origin. Ecotypes from arid habitats have earlier dormancy induction and delayed dormancy relaxation, compared with those from mesic habitats. PMID:20156924

  18. Transient decreases in methylation at 5'-cCGG-3' sequences in potato (Solanum tuberosum L.) meristem DNA during progression of tubers through dormancy precede the resumption of sprout growth.

    PubMed

    Law, R David; Suttle, Jeffrey C

    2003-02-01

    The 5-methylcytosine (5mC) content in DNA of tuber meristems isolated from field-grown potatoes (Solanum tuberosum L.) was determined during a 7-month storage period at 3 degrees C for three growing/postharvest seasons. No significant changes in 5mC levels were noted genome-wide or within 5'-CG-3' dinucleotide sequences, 5'-CG-3' islands or 5'-CA(T)G-3' trinucleotide sequences during storage. However, a consistent but transient 50-70% decrease in methylation at both cytosines within 5'-CCGG-3' sequences was detected that peaked 112-194 days after harvest. This result was corroborated by methylation-sensitive amplified fragment length polymorphism analysis of meristem DNA. Similar to tuber meristems undergoing progression through natural dormancy, premature chemical termination of dormancy resulted in rapid, transient 5'-CCGG-3' demethylation in meristem DNA. Minimum methylation levels at this sequence preceded initiation of high levels of de novo DNA synthesis by two days. Cytosine methylation status was also followed in in vitro-generated potato microtubers during 7 months of post-harvest storage. As in DNA from tuber bud meristems, no changes in genome-wide 5mC content or methylation at 5'-CA(T)G-3' or 5'-CG-3' island sequences were noted in microtuber DNA. However, there was a transient 46% drop in methylation at 5'-CG-3' dinucleotides concomitant with minimum levels of 5'-CCGG-3' methylation (30-60% below those in dormant microtubers) 57-98 days after harvest. As microtubers exited dormancy, there were sustained three- and seven-fold increases in RNA and DNA synthesis rates, peaking on or after 98 days of storage, respectively. Together, these data demonstrate that demethylation of 5'-CCGG-3' sequences occurs independently of tuber age during dormancy progression and precedes transcriptional activation of genes leading to cell division and meristem growth in potatoes. PMID:12602873

  19. Identification and Quality Assessment of Chrysanthemum Buds by CE Fingerprinting

    PubMed Central

    Xing, Xiaoping; Li, Dan

    2015-01-01

    A simple and efficient fingerprinting method for chrysanthemum buds was developed with the aim of establishing a quality control protocol based on biochemical makeup. Chrysanthemum bud samples were successively extracted by water and alcohol. The fingerprints of the chrysanthemum buds samples were obtained using capillary electrophoresis and electrochemical detection (CE-ED) employing copper and carbon working electrodes to capture all of the chemical information. 10 batches of chrysanthemum buds were collected from different regions and various factories to establish the baseline fingerprint. The experimental data of 10 batches electropherogram buds by CE were analyzed by correlation coefficient and the included angle cosine methods. A standard chrysanthemum bud fingerprint including 24 common peaks was established, 12 from each electrode, which was successfully applied to identify and distinguish between chrysanthemum buds from 2 other chrysanthemum species. These results demonstrate that fingerprint analysis can be used as an important criterion for chrysanthemum buds quality control. PMID:26064777

  20. Cryopreservation of Salix sp. dormant winter buds

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In cryopreservation, using dormant winter buds (DB) as source plant materials is economically advantageous over tissue culture options (TC). Processing DB does not require aseptic conditions and elaborate cryopreservation procedures. However, the DB approach is only feasible for cryopreserving a sel...

  1. Bilingual Buds: The Evolution of a Program

    ERIC Educational Resources Information Center

    Huang, Sharon

    2009-01-01

    The impetus to begin Bilingual Buds came about six years ago when the author, pregnant with twins and commuting into New York City, was reading about the numerous cognitive benefits for children of acquiring a second language early in their lives. She was surprised to learn that even by the age of six months, children begin to lose the ability to…

  2. Dormant bud preservation for germplasm conservation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The suitability of dormant buds (DB) for cryopreservation of different plant species has been demonstrated in several reports. For the majority of the species, processing DB for long-term liquid nitrogen storage does not involve establishing tissue cultures and the time for growing out post-cryo mat...

  3. IDENTIFICATION OF QUANTITATIVE TRAIT LOCI CONTROLLING SEED DORMANCY IN WEEDY RICE (ORYZA SATIVA).

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Seed dormancy contributes to adaptability of wild species, arrests development of the plant, and is a key factor in crop domestication. Our research has determined that seed dormancy is much stronger and heritability for the trait is higher in most weedy rice strains as compared with that in dormant...

  4. Two Faces of One Seed: Hormonal Regulation of Dormancy and Germination.

    PubMed

    Shu, Kai; Liu, Xiao-Dong; Xie, Qi; He, Zu-Hua

    2016-01-01

    Seed plants have evolved to maintain the dormancy of freshly matured seeds until the appropriate time for germination. Seed dormancy and germination are distinct physiological processes, and the transition from dormancy to germination is not only a critical developmental step in the life cycle of plants but is also important for agricultural production. These processes are precisely regulated by diverse endogenous hormones and environmental cues. Although ABA (abscisic acid) and GAs (gibberellins) are known to be the primary phytohormones that antagonistically regulate seed dormancy, recent findings demonstrate that another phytohormone, auxin, is also critical for inducing and maintaining seed dormancy, and therefore might act as a key protector of seed dormancy. In this review, we summarize our current understanding of the sophisticated molecular networks involving the critical roles of phytohormones in regulating seed dormancy and germination, in which AP2-domain-containing transcription factors play key roles. We also discuss the interactions (crosstalk) of diverse hormonal signals in seed dormancy and germination, focusing on the ABA/GA balance that constitutes the central node. PMID:26343970

  5. Seed dormancy variability in the U.S. peanut mini-core collection

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Seed dormancy is a naturally important biological process which can affect planting, germinating, and harvesting in agricultural production. Variability in seed dormancy within the U.S. peanut mini-core collection had not been determined. Freshly harvested seeds in the same field from 103 accessions...

  6. A transgenic approach to controlling wheat seed dormancy level by using Triticeae DOG1-like genes.

    PubMed

    Ashikawa, Ikuo; Mori, Masahiko; Nakamura, Shingo; Abe, Fumitaka

    2014-08-01

    Seed dormancy is an important agronomic trait: low levels can cause premature germination, while too much can inhibit uniform germination. As an approach to controlling the seed dormancy level in crops, we used Triticeae DOG1-like genes as transgenes. DOG1 is an Arabidopsis gene that underlies natural variation in seed dormancy. We previously showed that although their sequence similarities to DOG1 were low, some cereal DOG1-like genes enhanced seed dormancy in Arabidopsis. Here, we introduced two DOG1-like genes, TaDOG1L4 from wheat and HvDOG1L1 from barley, individually into the wheat cultivar Fielder. Their overexpression under the control of a maize ubiquitin promoter enhanced the seed dormancy level while leaving other traits unchanged. TaDOG1L4 was more effective than HvDOG1L1, which accords with the previously revealed difference in the effectiveness of these two genes in Arabidopsis seed dormancy. Knockdown of endogenous TaDOG1L4 in Fielder using double-strand RNA interference decreased the seed dormancy level by several tens of percent. This result indicates that some degree of seed dormancy inherent in wheat is imparted by DOG1-like genes. PMID:24752830

  7. Prolonged pupal dormancy is associated with significant fitness cost for adults of Rhagoletis cerasi (Diptera: Tephritidae).

    PubMed

    Moraiti, Cleopatra A; Nakas, Christos T; Papadopoulos, Nikos T

    2012-08-01

    In temperate areas, dormancy (diapause and/or quiescence) enables herbivorous insect species to persist and thrive by synchronizing growth and reproduction with the seasonal phenology of their host plants. Within-population variability in dormancy increases survival chances under unpredictable environmental changes. However, prolonged dormancy may be costly, incurring trade-offs in important adult fitness traits such as life span and reproduction. We used the European cherry fruit fly, Rhagoletis cerasi, a stenophagous, univoltine species that overwinters in the pupal stage for usually one or more years to test the hypotheses that prolonged dormancy of pupae has trade-offs with body size, survival and reproduction of the resulting adults. We used two geographically isolated populations of R. cerasi to compare the demographic traits of adults obtained from pupae subjected to one or two cycles of warm-cold periods (annual and prolonged dormancy respectively). Regardless of population, adults from pupae that experienced prolonged dormancy were larger than counterparts emerging within 1year. Prolonged dormancy did not affect adult longevity but both lifetime fecundity and oviposition were significantly decreased. Extension of the life cycle of some individuals in R. cerasi populations in association with prolonged dormancy is likely a bet-hedging strategy. PMID:22684113

  8. Comparison of gene expression changes in potato meristems during dormancy cessation and treatment with bromoethane

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Meristem dormancy in perennial plants is a developmental process that results in repression of metabolism and growth. The cessation of dormancy results in rapid growth and should be associated the production of nascent transcripts that encode for gene products controlling for cell division and growt...

  9. qSD7-1 is the first dormancy QTL cloned from weedy rice

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We answered a long-standing question about if the same or linked genes control the association between seed dormancy and grain color in grasses by map-based cloning a cluster of quantitative trait loci (QTL) for dormancy (qSD7-1) and pericarp color (qPC7 or Rc) from rice. A 2-cM region encompassing ...

  10. Ethylene Is Not Involved in Hormone- and Bromoethane-Induced Dormancy Break in Russet Burbank Minitubers

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The involvement of ethylene in the dormancy breaking actions of cytokinins, GA, and BE was investigated using Russet Burbank minitubers. Injection of 10µg tuber-1 BA, CP, GA, NG, or ZEA or 24 hour exposure to BE effectively broke dormancy and stimulated sprout growth over a two-week period. Althou...

  11. Grain dormancy and light quality effects on germination in the model grass Brachypodium distachyon

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Lack of seed dormancy in cereal crops such as barley and wheat is a common problem affecting farming areas around the world, causing losses in yield and quality due to pre-harvest sprouting. Control of seed dormancy has been investigated extensively using various approaches in different species incl...

  12. Mapping fall dormancy and winter injury in tetraploid alfalfa (Medicago sativa L.)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Alfalfa is a widely planted perennial forage crop. Dormancy in autumn (fall dormancy) is generally negatively correlated with winter injury in alfalfa. To understand the genetic basis of the two traits, we identified quantitative trait loci (QTL) controlling autumn growth and winter injury using a...

  13. The biology and clinical implications of prostate cancer dormancy and metastasis.

    PubMed

    Morrissey, Colm; Vessella, Robert L; Lange, Paul H; Lam, Hung-Ming

    2016-03-01

    Disseminated tumor cells (DTCs) are detected early in the disease process in prostate cancer (PCa) patients and can persist after radical prostatectomy. DTCs can remain dormant in patients with no evidence of disease for a prolonged period of time only to recur 10 or more years later. Recent advances in single-cell genomics and transcriptomics have provided much needed insight into DTC biology and cancer dormancy in patients. With the development of new in vitro and preclinical models, researchers recapitulate the clinical events in patients and therefore allow further elucidation of the molecular mechanisms underlying cancer dormancy and escape. In this review, we explore novel ideas on the detection, heterogeneous transcriptomic profiles, molecular and cellular mechanisms of dormancy, and potential mechanisms underlying dormancy escape by DTCs. As such, there is hope that identifying and targeting novel dormancy-associated pathways in patients with residual disease will have significant clinical implications for the treatment of PCa patients in the future. PMID:26489605

  14. Microbial dormancy improves development and experimental validation of ecosystem model

    PubMed Central

    Wang, Gangsheng; Jagadamma, Sindhu; Mayes, Melanie A; Schadt, Christopher W; Megan Steinweg, J; Gu, Lianhong; Post, Wilfred M

    2015-01-01

    Climate feedbacks from soils can result from environmental change followed by response of plant and microbial communities, and/or associated changes in nutrient cycling. Explicit consideration of microbial life-history traits and functions may be necessary to predict climate feedbacks owing to changes in the physiology and community composition of microbes and their associated effect on carbon cycling. Here we developed the microbial enzyme-mediated decomposition (MEND) model by incorporating microbial dormancy and the ability to track multiple isotopes of carbon. We tested two versions of MEND, that is, MEND with dormancy (MEND) and MEND without dormancy (MEND_wod), against long-term (270 days) carbon decomposition data from laboratory incubations of four soils with isotopically labeled substrates. MEND_wod adequately fitted multiple observations (total C–CO2 and 14C–CO2 respiration, and dissolved organic carbon), but at the cost of significantly underestimating the total microbial biomass. MEND improved estimates of microbial biomass by 20–71% over MEND_wod. We also quantified uncertainties in parameters and model simulations using the Critical Objective Function Index method, which is based on a global stochastic optimization algorithm, as well as model complexity and observational data availability. Together our model extrapolations of the incubation study show that long-term soil incubations with experimental data for multiple carbon pools are conducive to estimate both decomposition and microbial parameters. These efforts should provide essential support to future field- and global-scale simulations, and enable more confident predictions of feedbacks between environmental change and carbon cycling. PMID:25012899

  15. Cryptococcus neoformans Host Adaptation: Toward Biological Evidence of Dormancy

    PubMed Central

    Vernel-Pauillac, Frédérique; Sturny-Leclère, Aude; Dromer, Françoise

    2015-01-01

    ABSTRACT Cryptococcosis is an opportunistic infection due to the ubiquitous yeast Cryptococcus neoformans. This yeast interacts closely with innate immune cells, leading to various fates, including fungal persistence within cells, making possible the dissemination of the yeast cells with monocytes via a Trojan horse strategy. In humans, the natural history of the infection begins with primoinfection during childhood, which is followed by dormancy and, in some individuals, reactivation upon immunosuppression. To address the question of dormancy, we studied C. neoformans infection at the macrophage level (in vitro H99-macrophage interaction) and at the organ level in a murine model of cryptococcosis. We analyzed the diversity of yeast adaptation to the host by characterizing several C. neoformans populations with new assays based on flow cytometry (quantitative flow cytometry, multispectral imaging flow cytometry, sorting), microscopy (dynamic imaging), and gene expression analysis. On the basis of parameters of multiplication and stress response, various populations of yeast cells were observed over time in vivo and in vitro. Cell sorting allowed the identification of a subpopulation that was less prone to grow under standard conditions than the other populations, with growth enhanced by the addition of serum. Gene expression analysis revealed that this population had specific metabolic characteristics that could reflect dormancy. Our data suggest that dormant yeast cells could exist in vitro and in vivo. C. neoformans exhibits a huge plasticity and adaptation to hosts that deserves further study. In vitro generation of dormant cells is now the main challenge to overcome the limited number of yeast cells recovered in our models. PMID:25827423

  16. Transcriptomic analysis of American ginseng seeds during the dormancy release process by RNA-Seq.

    PubMed

    Qi, Jianjun; Sun, Peng; Liao, Dengqun; Sun, Tongyu; Zhu, Juan; Li, Xianen

    2015-01-01

    American ginseng (Panax quinquefolius L.) is an important herb that is cultivated in China, North American, and South Korea. It is propagated from seed, but the seed has deep dormancy characteristics described as morphophysiological dormancy. Two-stage temperature stratification, a warm (15-20°C) and cold (2°C) stratification period of 6 months, has been used successfully for seed dormancy release. However, little is known about the molecular mechanisms of seed dormancy release in the stratification process. In this study, seed development after pollination and seed development in the dormancy release process were investigated in American ginseng. The transcriptome during seed dormancy release was analyzed using RNA-Seq technology and 78,207 unigenes (mean length 531 bp) were generated. Based on similarity searches of public databases, 54,292 of the unigenes (69.4%) were functionally annotated. Further, three digital gene expression (DGE) libraries were sequenced and differences in gene expression at three stages during seed cold stratification were examined. The greatest number of differentially expressed genes occurred in the 90DCS versus 180DCS libraries, while the lowest number of differentially expressed genes occurred in the 135DCS verus 180DCS libraries. GO enrichment analysis revealed that 59, 29, and 39 GO terms were significantly enriched in the biological process, molecular function, and cell component GO categories, respectively. There were 25,190 genes with KEGG pathway annotation in the three DGE libraries and their enrichment pathways were compared. The gene expressions of 30 selected unigenes were validated using quantitative PCR. This study is the first to provide the transcriptome sequences for seed dormancy release in American ginseng, and demonstrates the successful use of DGE profiling data for analyzing transcriptomic variation during dormancy release. These data provide a basis for future researches of seed dormancy in morphophysiological dormancy seeds in non-model plants. PMID:25790114

  17. A Causal Gene for Seed Dormancy on Wheat Chromosome 4A Encodes a MAP Kinase Kinase.

    PubMed

    Torada, Atsushi; Koike, Michiya; Ogawa, Taiichi; Takenouchi, Yu; Tadamura, Kazuki; Wu, Jianzhong; Matsumoto, Takashi; Kawaura, Kanako; Ogihara, Yasunari

    2016-03-21

    Seed germination under the appropriate environmental conditions is important both for plant species survival and for successful agriculture. Seed dormancy, which controls germination time, is one of the adaptation mechanisms and domestication traits [1]. Seed dormancy is generally defined as the absence of germination of a viable seed under conditions that are favorable for germination [2]. The seed dormancy of cultivated plants has generally been reduced during domestication [3]. Bread wheat (Triticum aestivum L.) is one of the most widely grown crops in the world. Weak dormancy may be an advantage for the productivity due to uniform emergence and a disadvantage for the risks of pre-harvest sprouting (PHS), which decreases grain quality and yield [4]. A number of quantitative trait loci (QTLs) controlling natural variation of seed dormancy have been identified on various chromosomes [5]. A major QTL for seed dormancy has been consistently detected on chromosome 4A [6-13]. The QTL was designated as a major gene, Phs1, which could be precisely mapped within a 2.6 cM region [14]. Here, we identified a mitogen-activated protein kinase kinase 3 (MKK3) gene (designated TaMKK3-A) by a map-based approach as a candidate gene for the seed dormancy locus Phs1 on chromosome 4A in bread wheat. Complementation analysis showed that transformation of a dormant wheat cultivar with the TaMKK3-A allele from a nondormant cultivar clearly reduced seed dormancy. Cultivars differing in dormancy had a single nonsynonymous amino acid substitution in the kinase domain of the predicted MKK3 protein sequence, which may be associated with the length of seed dormancy. PMID:26948878

  18. Transcriptomic Analysis of American Ginseng Seeds during the Dormancy Release Process by RNA-Seq

    PubMed Central

    Qi, Jianjun; Sun, Peng; Liao, Dengqun; Sun, Tongyu; Zhu, Juan; Li, Xianen

    2015-01-01

    American ginseng (Panax quinquefolius L.) is an important herb that is cultivated in China, North American, and South Korea. It is propagated from seed, but the seed has deep dormancy characteristics described as morphophysiological dormancy. Two-stage temperature stratification, a warm (15–20°C) and cold (2°C) stratification period of 6 months, has been used successfully for seed dormancy release. However, little is known about the molecular mechanisms of seed dormancy release in the stratification process. In this study, seed development after pollination and seed development in the dormancy release process were investigated in American ginseng. The transcriptome during seed dormancy release was analyzed using RNA-Seq technology and 78,207 unigenes (mean length 531 bp) were generated. Based on similarity searches of public databases, 54,292 of the unigenes (69.4%) were functionally annotated. Further, three digital gene expression (DGE) libraries were sequenced and differences in gene expression at three stages during seed cold stratification were examined. The greatest number of differentially expressed genes occurred in the 90DCS versus 180DCS libraries, while the lowest number of differentially expressed genes occurred in the 135DCS verus 180DCS libraries. GO enrichment analysis revealed that 59, 29, and 39 GO terms were significantly enriched in the biological process, molecular function, and cell component GO categories, respectively. There were 25,190 genes with KEGG pathway annotation in the three DGE libraries and their enrichment pathways were compared. The gene expressions of 30 selected unigenes were validated using quantitative PCR. This study is the first to provide the transcriptome sequences for seed dormancy release in American ginseng, and demonstrates the successful use of DGE profiling data for analyzing transcriptomic variation during dormancy release. These data provide a basis for future researches of seed dormancy in morphophysiological dormancy seeds in non-model plants. PMID:25790114

  19. REDUCED DORMANCY5 Encodes a Protein Phosphatase 2C That Is Required for Seed Dormancy in Arabidopsis[C][W][OPEN

    PubMed Central

    Xiang, Yong; Nakabayashi, Kazumi; Ding, Jia; He, Fei; Bentsink, Leónie; Soppe, Wim J.J.

    2014-01-01

    Seed dormancy determines germination timing and contributes to crop production and the adaptation of natural populations to their environment. Our knowledge about its regulation is limited. In a mutagenesis screen of a highly dormant Arabidopsis thaliana line, the reduced dormancy5 (rdo5) mutant was isolated based on its strongly reduced seed dormancy. Cloning of RDO5 showed that it encodes a PP2C phosphatase. Several PP2C phosphatases belonging to clade A are involved in abscisic acid signaling and control seed dormancy. However, RDO5 does not cluster with clade A phosphatases, and abscisic acid levels and sensitivity are unaltered in the rdo5 mutant. RDO5 transcript could only be detected in seeds and was most abundant in dry seeds. RDO5 was found in cells throughout the embryo and is located in the nucleus. A transcriptome analysis revealed that several genes belonging to the conserved PUF family of RNA binding proteins, in particular Arabidopsis PUMILIO9 (APUM9) and APUM11, showed strongly enhanced transcript levels in rdo5 during seed imbibition. Further transgenic analyses indicated that APUM9 reduces seed dormancy. Interestingly, reduction of APUM transcripts by RNA interference complemented the reduced dormancy phenotype of rdo5, indicating that RDO5 functions by suppressing APUM transcript levels. PMID:25415980

  20. View of east entrance to Flume Tunnel #2. In foreground, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    View of east entrance to Flume Tunnel #2. In foreground, covered decking (covered by debris) protects the flume below it (not visible). The extreme top of the tunnel entrance is visible in the middle of the picture, just beyond the covered decking. This is typical of gravity tunnel entrances and the only photograph representing these features in the system. Looking south - Childs-Irving Hydroelectric Project, Childs System, Flume Tunnel No. 2, Forest Service Road 708/502, Camp Verde, Yavapai County, AZ

  1. ENTRANCE GATE AND MEMORIAL AVENUE APPROACH, LOOKING INTO CEMETERY WITH ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    ENTRANCE GATE AND MEMORIAL AVENUE APPROACH, LOOKING INTO CEMETERY WITH ADMINISTRATION BUILDING IN BACKGROUND. VIEW TO NORTHWEST. - Mountain Home National Cemetery, Mountain Home, Washington County, TN

  2. 15. North Plant, South Entrance on Southeast Elevation (location of ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    15. North Plant, South Entrance on Southeast Elevation (location of former 1929 bridge), Looking Northwest - Atwater Kent Manufacturing Company, North Plant, 5000 Wissahickon Avenue, Philadelphia, Philadelphia County, PA

  3. 3. HISTORIC AMERICAN BUILDINGS SURVEY S. Lucas, Photographer, 1934 ENTRANCE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    3. HISTORIC AMERICAN BUILDINGS SURVEY S. Lucas, Photographer, 1934 ENTRANCE DETAIL. OFFICERS' QUARTERS. DETROIT ARSENAL. DEARBORN. MICHIGAN. - Detroit Arsenal, Officers' Quarters, 21950 Michigan Avenue, Dearborn, Wayne County, MI

  4. 56. SOUTH ENTRANCE DOORS WITH RESTORED FANLIGHT, LOOKING SOUTH ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    56. SOUTH ENTRANCE DOORS WITH RESTORED FANLIGHT, LOOKING SOUTH - Smithsonian Institution Building, 1000 Jefferson Drive, between Ninth & Twelfth Streets, Southwest, Washington, District of Columbia, DC

  5. INTERIOR VIEW OF ENTRANCE TO LABORATORY, SHOWING HANDHAMMERED ALUMINUM DOORS ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    INTERIOR VIEW OF ENTRANCE TO LABORATORY, SHOWING HAND-HAMMERED ALUMINUM DOORS AND MARBLE. NOTE ALUMINUM LIGHT FIXTURE - Alcoa Research Laboratory, Freeport Road, New Kensington, Westmoreland County, PA

  6. Perspective view of east entrance from northeast National Home ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Perspective view of east entrance from northeast - National Home for Disabled Volunteer Soldiers, Pacific Branch, Mental Health Building, 11301 Wilshire Boulevard, West Los Angeles, Los Angeles County, CA

  7. Building, north side (original front), detail of original entrance. Camera ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Building, north side (original front), detail of original entrance. Camera facing south - Naval Supply Center, Broadway Complex, Administration Storehouse, 911 West Broadway, San Diego, San Diego County, CA

  8. 6. WEST FRONT DETAIL, SHOWING AUTO ENTRANCE, WINDOWS AND MASONRY. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    6. WEST FRONT DETAIL, SHOWING AUTO ENTRANCE, WINDOWS AND MASONRY. VIEW TO NORTH. - Commercial & Industrial Buildings, Dubuque Oat Meal Mill Powerhouse, Seventh & Washington Streets, Dubuque, Dubuque County, IA

  9. double hung window details, hall window details, entrance door profiles ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    double hung window details, hall window details, entrance door profiles - Chopawamsic Recreational Demonstration Area - Cabin Camp 1, Help's Quarters, Prince William Forest Park, Triangle, Prince William County, VA

  10. 7. INTERIOR, VIEW FROM ENTRANCE TOWARD ENCLOSED STAIRS AND REAR ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    7. INTERIOR, VIEW FROM ENTRANCE TOWARD ENCLOSED STAIRS AND REAR DOOR - Mulliken-Spragins Tenant House, National Museum of American History, Smithsonian Institution, Washington, District of Columbia, DC

  11. Actomyosin ring driven cytokinesis in budding yeast.

    PubMed

    Meitinger, Franz; Palani, Saravanan

    2016-05-01

    Cytokinesis is the final process in the cell cycle that physically divides one cell into two. In budding yeast, cytokinesis is driven by a contractile actomyosin ring (AMR) and the simultaneous formation of a primary septum, which serves as template for cell wall deposition. AMR assembly, constriction, primary septum formation and cell wall deposition are successive processes and tightly coupled to cell cycle progression to ensure the correct distribution of genetic material and cell organelles among the two rising cells prior to cell division. The role of the AMR in cytokinesis and the molecular mechanisms that drive AMR constriction and septation are the focus of current research. This review summarizes the recent progresses in our understanding of how budding yeast cells orchestrate the multitude of molecular mechanisms that control AMR driven cytokinesis in a spatio-temporal manner to achieve an error free cell division. PMID:26845196

  12. Single-cell phenomics in budding yeast.

    PubMed

    Ohya, Yoshikazu; Kimori, Yoshitaka; Okada, Hiroki; Ohnuki, Shinsuke

    2015-11-01

    The demand for phenomics, a high-dimensional and high-throughput phenotyping method, has been increasing in many fields of biology. The budding yeast Saccharomyces cerevisiae, a unicellular model organism, provides an invaluable system for dissecting complex cellular processes using high-resolution phenotyping. Moreover, the addition of spatial and temporal attributes to subcellular structures based on microscopic images has rendered this cell phenotyping system more reliable and amenable to analysis. A well-designed experiment followed by appropriate multivariate analysis can yield a wealth of biological knowledge. Here we review recent advances in cell imaging and illustrate their broad applicability to eukaryotic cells by showing how these techniques have advanced our understanding of budding yeast. PMID:26543200

  13. Single-cell phenomics in budding yeast

    PubMed Central

    Ohya, Yoshikazu; Kimori, Yoshitaka; Okada, Hiroki; Ohnuki, Shinsuke

    2015-01-01

    The demand for phenomics, a high-dimensional and high-throughput phenotyping method, has been increasing in many fields of biology. The budding yeast Saccharomyces cerevisiae, a unicellular model organism, provides an invaluable system for dissecting complex cellular processes using high-resolution phenotyping. Moreover, the addition of spatial and temporal attributes to subcellular structures based on microscopic images has rendered this cell phenotyping system more reliable and amenable to analysis. A well-designed experiment followed by appropriate multivariate analysis can yield a wealth of biological knowledge. Here we review recent advances in cell imaging and illustrate their broad applicability to eukaryotic cells by showing how these techniques have advanced our understanding of budding yeast. PMID:26543200

  14. HIV-1 Assembly, Budding, and Maturation

    PubMed Central

    Sundquist, Wesley I.; Kräusslich, Hans-Georg

    2012-01-01

    A defining property of retroviruses is their ability to assemble into particles that can leave producer cells and spread infection to susceptible cells and hosts. Virion morphogenesis can be divided into three stages: assembly, wherein the virion is created and essential components are packaged; budding, wherein the virion crosses the plasma membrane and obtains its lipid envelope; and maturation, wherein the virion changes structure and becomes infectious. All of these stages are coordinated by the Gag polyprotein and its proteolytic maturation products, which function as the major structural proteins of the virus. Here, we review our current understanding of the mechanisms of HIV-1 assembly, budding, and maturation, starting with a general overview and then providing detailed descriptions of each of the different stages of virion morphogenesis. PMID:22762019

  15. Role of Endogenous Abscisic Acid in Potato Microtuber Dormancy.

    PubMed Central

    Suttle, J. C.; Hultstrand, J. F.

    1994-01-01

    Potato (Solanum tuberosum L. cv Russet Burbank) microtubers generated in vitro from single-node explants contained substantial amounts (approximately 250 pmol/g fresh weight) of free abscisic acid (ABA) and were completely dormant for a minimum of 12 weeks. Microtubers that developed in the presence of 10 [mu]M fluridone (FLD) contained considerably reduced amounts (approximately 5-25 pmol/g fresh weight) of free ABA and exhibited a precocious loss of dormancy. Inclusion of exogenous racemic ABA in the FLD-containing medium suppressed the premature sprouting of these microtubers in a dose-dependent manner. At a concentration of 50 [mu]M, exogenous ABA restored internal ABA levels to control values and completely inhibited FLD-induced precocious sprouting. Exogenous jasmonic acid was ineffective in suppressing FLD-induced sprouting. Application of FLD to preformed, fully dormant microtubers also resulted in a reduction in internal ABA content and precocious sprouting. These results indicate that endogenous ABA is essential for the induction and maintenance of potato microtuber dormancy. PMID:12232251

  16. Role of Endogenous Abscisic Acid in Potato Microtuber Dormancy.

    PubMed

    Suttle, J. C.; Hultstrand, J. F.

    1994-07-01

    Potato (Solanum tuberosum L. cv Russet Burbank) microtubers generated in vitro from single-node explants contained substantial amounts (approximately 250 pmol/g fresh weight) of free abscisic acid (ABA) and were completely dormant for a minimum of 12 weeks. Microtubers that developed in the presence of 10 [mu]M fluridone (FLD) contained considerably reduced amounts (approximately 5-25 pmol/g fresh weight) of free ABA and exhibited a precocious loss of dormancy. Inclusion of exogenous racemic ABA in the FLD-containing medium suppressed the premature sprouting of these microtubers in a dose-dependent manner. At a concentration of 50 [mu]M, exogenous ABA restored internal ABA levels to control values and completely inhibited FLD-induced precocious sprouting. Exogenous jasmonic acid was ineffective in suppressing FLD-induced sprouting. Application of FLD to preformed, fully dormant microtubers also resulted in a reduction in internal ABA content and precocious sprouting. These results indicate that endogenous ABA is essential for the induction and maintenance of potato microtuber dormancy. PMID:12232251

  17. Overexpression of the kiwifruit SVP3 gene affects reproductive development and suppresses anthocyanin biosynthesis in petals, but has no effect on vegetative growth, dormancy, or flowering time.

    PubMed

    Wu, Rongmei; Wang, Tianchi; McGie, Tony; Voogd, Charlotte; Allan, Andrew C; Hellens, Roger P; Varkonyi-Gasic, Erika

    2014-09-01

    SVP-like MADS domain transcription factors have been shown to regulate flowering time and both inflorescence and flower development in annual plants, while having effects on growth cessation and terminal bud formation in perennial species. Previously, four SVP genes were described in woody perennial vine kiwifruit (Actinidia spp.), with possible distinct roles in bud dormancy and flowering. Kiwifruit SVP3 transcript was confined to vegetative tissues and acted as a repressor of flowering as it was able to rescue the Arabidopsis svp41 mutant. To characterize kiwifruit SVP3 further, ectopic expression in kiwifruit species was performed. Ectopic expression of SVP3 in A. deliciosa did not affect general plant growth or the duration of endodormancy. Ectopic expression of SVP3 in A. eriantha also resulted in plants with normal vegetative growth, bud break, and flowering time. However, significantly prolonged and abnormal flower, fruit, and seed development were observed, arising from SVP3 interactions with kiwifruit floral homeotic MADS-domain proteins. Petal pigmentation was reduced as a result of SVP3-mediated interference with transcription of the kiwifruit flower tissue-specific R2R3 MYB regulator, MYB110a, and the gene encoding the key anthocyanin biosynthetic step, F3GT1. Constitutive expression of SVP3 had a similar impact on reproductive development in transgenic tobacco. The flowering time was not affected in day-neutral and photoperiod-responsive Nicotiana tabacum cultivars, but anthesis and seed germination were significantly delayed. The accumulation of anthocyanin in petals was reduced and the same underlying mechanism of R2R3 MYB NtAN2 transcript reduction was demonstrated. PMID:24948678

  18. Overexpression of the kiwifruit SVP3 gene affects reproductive development and suppresses anthocyanin biosynthesis in petals, but has no effect on vegetative growth, dormancy, or flowering time

    PubMed Central

    Wu, Rongmei; Wang, Tianchi; McGie, Tony; Voogd, Charlotte; Allan, Andrew C.; Hellens, Roger P.; Varkonyi-Gasic, Erika

    2014-01-01

    SVP-like MADS domain transcription factors have been shown to regulate flowering time and both inflorescence and flower development in annual plants, while having effects on growth cessation and terminal bud formation in perennial species. Previously, four SVP genes were described in woody perennial vine kiwifruit (Actinidia spp.), with possible distinct roles in bud dormancy and flowering. Kiwifruit SVP3 transcript was confined to vegetative tissues and acted as a repressor of flowering as it was able to rescue the Arabidopsis svp41 mutant. To characterize kiwifruit SVP3 further, ectopic expression in kiwifruit species was performed. Ectopic expression of SVP3 in A. deliciosa did not affect general plant growth or the duration of endodormancy. Ectopic expression of SVP3 in A. eriantha also resulted in plants with normal vegetative growth, bud break, and flowering time. However, significantly prolonged and abnormal flower, fruit, and seed development were observed, arising from SVP3 interactions with kiwifruit floral homeotic MADS-domain proteins. Petal pigmentation was reduced as a result of SVP3-mediated interference with transcription of the kiwifruit flower tissue-specific R2R3 MYB regulator, MYB110a, and the gene encoding the key anthocyanin biosynthetic step, F3GT1. Constitutive expression of SVP3 had a similar impact on reproductive development in transgenic tobacco. The flowering time was not affected in day-neutral and photoperiod-responsive Nicotiana tabacum cultivars, but anthesis and seed germination were significantly delayed. The accumulation of anthocyanin in petals was reduced and the same underlying mechanism of R2R3 MYB NtAN2 transcript reduction was demonstrated. PMID:24948678

  19. Co-adaptation of seed dormancy and flowering time in the arable weed Capsella bursa-pastoris (shepherd's purse)

    PubMed Central

    Toorop, Peter E.; Campos Cuerva, Rafael; Begg, Graham S.; Locardi, Bruna; Squire, Geoff R.; Iannetta, Pietro P. M.

    2012-01-01

    Background and Aims The duration of the plant life cycle is an important attribute that determines fitness and coexistence of weeds in arable fields. It depends on the timing of two key life-history traits: time from seed dispersal to germination and time from germination to flowering. These traits are components of the time to reproduction. Dormancy results in reduced and delayed germination, thus increasing time to reproduction. Genotypes in the arable seedbank predominantly have short time to flowering. Synergy between reduced seed dormancy and reduced flowering time would create stronger contrasts between genotypes, offering greater adaptation in-field. Therefore, we studied differences in seed dormancy between in-field flowering time genotypes of shepherd's purse. Methods Genotypes with early, intermediate or late flowering time were grown in a glasshouse to provide seed stock for germination tests. Secondary dormancy was assessed by comparing germination before and after dark-incubation. Dormancy was characterized separately for seed myxospermy heteromorphs, observed in each genotype. Seed carbon and nitrogen content and seed mass were determined as indicators of seed filling and resource partitioning associated with dormancy. Key Results Although no differences were observed in primary dormancy, secondary dormancy was weaker among the seeds of early-flowering genotypes. On average, myxospermous seeds showed stronger secondary dormancy than non-myxospermous seeds in all genotypes. Seed filling was similar between the genotypes, but nitrogen partitioning was higher in early-flowering genotypes and in non-myxospermous seeds. Conclusions In shepherd's purse, early flowering and reduced seed dormancy coincide and appear to be linked. The seed heteromorphism contributes to variation in dormancy. Three functional groups of seed dormancy were identified, varying in dormancy depth and nitrate response. One of these groups (FG-III) was distinct for early-flowering genotypes. The weaker secondary dormancy of early-flowering genotypes confers a selective advantage in arable fields. PMID:22147546

  20. Dormancy, germination, emergence and ecology of Gardner saltbush (Atriplex gardneri (Moq. ) D. Dietr. ) seeds

    SciTech Connect

    Ansley, R.J. Jr.

    1983-01-01

    Gardner saltbush (Atriplex gardneri (Moq.) D. Dietr.) provides valuable winter browse and is an important soil stabilizer in arid, alkaline, and saline areas of the intermountain region. However, seed dormancy and poor seedling vigor inhibit its potential for revegetation by direct seeding on disturbed lands. The objectives of this study were to 1) develop seed treatments which would overcome dormancy in Gardner saltbush seeds, 2) evaluate field establishment by direct seeding of Gardner saltbush, and 3) characterize seed dormancy, seedling vigor and some aspects of the ecology of germination in Gardner saltbush. In the laboratory, single and combined pretreatments removed dormancy to varying degrees. Dormancy was completely alleviated with 15 months dry after-ripening + scarification + 24 hours washing + 4 weeks stratification. Dry after-ripening and scarification appeared to facilitate effects of washing and stratification. Physiologically, indirect evidence was obtained suggesting both embryo and seedcoat mediated dormancy occur in Gardner saltbush. Ecologically, the various levels of germination response to simulated environmental pretreatments appeared to be an adaptation of Gardner saltbush seeds to ensure a temporal dispersal of release from dormancy. This increases the probability that under natural conditions some seedlings will emerge during times when the environment is amenable to seedling survival.

  1. An immunoproteomic approach for characterization of dormancy within Staphylococcus epidermidis biofilms.

    PubMed

    Carvalhais, Virginia; Cerveira, Frederico; Vilanova, Manuel; Cerca, Nuno; Vitorino, Rui

    2015-06-01

    Virulence of Staphylococcus epidermidis is mainly attributed to surface colonization and biofilm formation in indwelling medical devices. Physiological heterogeneity of biofilms may influence host immune response and sensitivity to antibiotics. Dormant cells, among others, contribute to biofilm heterogeneity. The aim of this study was to identify immunogenic proteins of S. epidermidis biofilms associated with dormancy mechanism, by using two-dimensional electrophoresis (2-DE) immunoblotting and mass spectrometry (MS). A total of 19 bacterial proteins, recognized by human serum samples, were identified. These proteins were mainly involved in small molecule metabolic biological processes. Catalytic activity and ion binding were the most representative molecular functions. CodY and GpmA proteins were more reactive to sera when biofilm dormancy was induced, while FtnA and ClpP were more reactive when dormancy was prevented. This is the first work that identifies differences in immunoreactive proteins within bacterial biofilms with induced or prevented dormancy. Considering the importance of dormancy within biofilms, further evaluation of these proteins can provide insights into the mechanisms related to dormancy and help to improve current understanding on how dormancy affects the host immune response. PMID:25749707

  2. Seed Anatomy and Water Uptake in Relation to Seed Dormancy in Opuntia tomentosa (Cactaceae, Opuntioideae)

    PubMed Central

    Orozco-Segovia, A.; Márquez-Guzmán, J.; Sánchez-Coronado, M. E.; Gamboa de Buen, A.; Baskin, J. M.; Baskin, C. C.

    2007-01-01

    Background and Aims There is considerable confusion in the literature concerning impermeability of seeds with ‘hard’ seed coats, because the ability to take up (imbibe) water has not been tested in most of them. Seeds of Opuntia tomentosa were reported recently to have a water-impermeable seed coat sensu lato (i.e. physical dormancy), in combination with physiological dormancy. However, physical dormancy is not known to occur in Cactaceae. Therefore, the aim of this study was to determine if seeds of O. tomentosa are water-permeable or water-impermeable, i.e. if they have physical dormancy. Methods The micromorphology of the seed coat and associated structures were characterized by SEM and light microscopy. Permeability of the seed-covering layers was assessed by an increase in mass of seeds on a wet substrate and by dye-tracking and uptake of tritiated water by intact versus scarified seeds. Key Results A germination valve and a water channel are formed in the hilum–micropyle region during dehydration and ageing in seeds of O. tomentosa. The funicular envelope undoubtedly plays a role in germination of Opuntia seeds via restriction of water uptake and mechanical resistance to expansion of the embryo. However, seeds do not exhibit any of three features characteristic of those with physical dormancy. Thus, they do not have a water-impermeable layer(s) of palisade cells (macrosclereids) or a water gap sensu stricto and they imbibe water without the seed coat being disrupted. Conclusions Although dormancy in seeds of this species can be broken by scarification, they have physiological dormancy only. Further, based on information in the literature, it is concluded that it is unlikely that any species of Opuntia has physical dormancy. This is the first integrative study of the anatomy, dynamics of water uptake and dormancy in seeds of Cactaceae subfamily Opuntioideae. PMID:17298989

  3. Mitogen-Activated Protein Kinase Kinase 3 Regulates Seed Dormancy in Barley.

    PubMed

    Nakamura, Shingo; Pourkheirandish, Mohammad; Morishige, Hiromi; Kubo, Yuta; Nakamura, Masako; Ichimura, Kazuya; Seo, Shigemi; Kanamori, Hiroyuki; Wu, Jianzhong; Ando, Tsuyu; Hensel, Goetz; Sameri, Mohammad; Stein, Nils; Sato, Kazuhiro; Matsumoto, Takashi; Yano, Masahiro; Komatsuda, Takao

    2016-03-21

    Seed dormancy has fundamental importance in plant survival and crop production; however, the mechanisms regulating dormancy remain unclear [1-3]. Seed dormancy levels generally decrease during domestication to ensure that crops successfully germinate in the field. However, reduction of seed dormancy can cause devastating losses in cereals like wheat (Triticum aestivum L.) and barley (Hordeum vulgare L.) due to pre-harvest sprouting, the germination of mature seed (grain) on the mother plant when rain occurs before harvest. Understanding the mechanisms of dormancy can facilitate breeding of crop varieties with the appropriate levels of seed dormancy [4-8]. Barley is a model crop [9, 10] and has two major seed dormancy quantitative trait loci (QTLs), SD1 and SD2, on chromosome 5H [11-19]. We detected a QTL designated Qsd2-AK at SD2 as the single major determinant explaining the difference in seed dormancy between the dormant cultivar "Azumamugi" (Az) and the non-dormant cultivar "Kanto Nakate Gold" (KNG). Using map-based cloning, we identified the causal gene for Qsd2-AK as Mitogen-activated Protein Kinase Kinase 3 (MKK3). The dormant Az allele of MKK3 is recessive; the N260T substitution in this allele decreases MKK3 kinase activity and appears to be causal for Qsd2-AK. The N260T substitution occurred in the immediate ancestor allele of the dormant allele, and the established dormant allele became prevalent in barley cultivars grown in East Asia, where the rainy season and harvest season often overlap. Our findings show fine-tuning of seed dormancy during domestication and provide key information for improving pre-harvest sprouting tolerance in barley and wheat. PMID:26948880

  4. 33 CFR 110.194 - Mobile Bay, Ala., at entrance.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false Mobile Bay, Ala., at entrance. 110.194 Section 110.194 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY ANCHORAGES ANCHORAGE REGULATIONS Anchorage Grounds § 110.194 Mobile Bay, Ala., at entrance. (a) The...

  5. 15. Front security entrance to the perimeter acquisition radar building, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    15. Front security entrance to the perimeter acquisition radar building, showing rotogates 1 and 2 and entrance door to security operations control center (SOCC), room #108 - Stanley R. Mickelsen Safeguard Complex, Perimeter Acquisition Radar Building, Limited Access Area, between Limited Access Patrol Road & Service Road A, Nekoma, Cavalier County, ND

  6. 33 CFR 80.130 - Boston Harbor entrance.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Boston Harbor entrance. 80.130 Section 80.130 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY INTERNATIONAL NAVIGATION RULES COLREGS DEMARCATION LINES Atlantic Coast § 80.130 Boston Harbor entrance. A line drawn...

  7. 33 CFR 80.510 - Chesapeake Bay Entrance, VA.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Chesapeake Bay Entrance, VA. 80.510 Section 80.510 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY INTERNATIONAL NAVIGATION RULES COLREGS DEMARCATION LINES Fifth District § 80.510 Chesapeake Bay Entrance, VA....

  8. 7. CLOSEUP VIEW OF ENTRANCE TO BUILDING NO. 33 FACING ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    7. CLOSE-UP VIEW OF ENTRANCE TO BUILDING NO. 33 FACING EAST. VIEW SHOWS CONCRETE PLANTING BOXES ON EACH SIDE OF ENTRANCE AND CONCRETE CANOPY OVERHANG ABOVE. - U.S. Naval Base, Pearl Harbor, Marine Barracks, West Loch, B Avenue near Arizona Road, Pearl City, Honolulu County, HI

  9. 33 CFR 80.510 - Chesapeake Bay Entrance, VA.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 1 2013-07-01 2013-07-01 false Chesapeake Bay Entrance, VA. 80.510 Section 80.510 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY INTERNATIONAL NAVIGATION RULES COLREGS DEMARCATION LINES Fifth District § 80.510 Chesapeake Bay Entrance, VA....

  10. 33 CFR 80.510 - Chesapeake Bay Entrance, VA.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 1 2012-07-01 2012-07-01 false Chesapeake Bay Entrance, VA. 80.510 Section 80.510 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY INTERNATIONAL NAVIGATION RULES COLREGS DEMARCATION LINES Fifth District § 80.510 Chesapeake Bay Entrance, VA....

  11. 33 CFR 80.510 - Chesapeake Bay Entrance, VA.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 1 2014-07-01 2014-07-01 false Chesapeake Bay Entrance, VA. 80.510 Section 80.510 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY INTERNATIONAL NAVIGATION RULES COLREGS DEMARCATION LINES Fifth District § 80.510 Chesapeake Bay Entrance, VA....

  12. 33 CFR 80.510 - Chesapeake Bay Entrance, VA.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false Chesapeake Bay Entrance, VA. 80.510 Section 80.510 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY INTERNATIONAL NAVIGATION RULES COLREGS DEMARCATION LINES Fifth District § 80.510 Chesapeake Bay Entrance, VA....

  13. 33 CFR 110.194 - Mobile Bay, Ala., at entrance.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Mobile Bay, Ala., at entrance. 110.194 Section 110.194 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY ANCHORAGES ANCHORAGE REGULATIONS Anchorage Grounds § 110.194 Mobile Bay, Ala., at entrance. (a) The...

  14. Love and Work: The Legacy of Early University Entrance

    ERIC Educational Resources Information Center

    Noble, Kathleen D.; Vaughan, Robert C.; Chan, Christina; Childers, Sarah; Chow, Bryan; Federow, Ariel; Hughes, Sean

    2007-01-01

    This is the second follow-up study of the Early Entrance Program at the University of Washington. Ninety-five individuals (45%) participated. Respondents overwhelmingly chose early university entrance because they were excited to learn; many also praised the peer group, intellectual stimulation, and faculty and staff support. Some reported feeling…

  15. Auxin controls seed dormancy through stimulation of abscisic acid signaling by inducing ARF-mediated ABI3 activation in Arabidopsis

    PubMed Central

    Liu, Xiaodong; Zhang, Hong; Zhao, Yang; Feng, Zhengyan; Li, Qun; Yang, Hong-Quan; Luan, Sheng; Li, Jianming; He, Zu-Hua

    2013-01-01

    The transition from dormancy to germination in seeds is a key physiological process during the lifecycle of plants. Abscisic acid (ABA) is the sole plant hormone known to maintain seed dormancy; it acts through a gene expression network involving the transcription factor ABSCISIC ACID INSENSITIVE 3 (ABI3). However, whether other phytohormone pathways function in the maintenance of seed dormancy in response to environmental and internal signals remains an important question. Here, we show that the plant growth hormone auxin, which acts as a versatile trigger in many developmental processes, also plays a critical role in seed dormancy in Arabidopsis. We show that disruptions in auxin signaling in MIR160-overexpressing plants, auxin receptor mutants, or auxin biosynthesis mutants dramatically release seed dormancy, whereas increases in auxin signaling or biosynthesis greatly enhance seed dormancy. Auxin action in seed dormancy requires the ABA signaling pathway (and vice versa), indicating that the roles of auxin and ABA in seed dormancy are interdependent. Furthermore, we show that auxin acts upstream of the major regulator of seed dormancy, ABI3, by recruiting the auxin response factors AUXIN RESPONSE FACTOR 10 and AUXIN RESPONSE FACTOR 16 to control the expression of ABI3 during seed germination. Our study, thus, uncovers a previously unrecognized regulatory factor of seed dormancy and a coordinating network of auxin and ABA signaling in this important process. PMID:23986496

  16. Temperature-mediated changes in seed dormancy and light requirement for Penstemon palmeri (Scrophulariaceae)

    SciTech Connect

    Kitchen, S.G.; Meyer, S.E. )

    1992-03-01

    Penstemon palmeri is a short-lived perennial herb colonizing disturbed sites in semiarid habitats in the western US. In this study seed was harvested from six native and four seeded populations during two consecutive years. In laboratory germination trials at constant 15C, considerable between-lot variation in primary dormancy and light requirement was observed. Four weeks of moist chilling (1C) induced secondary dormancy at 15C. Cold-induced secondary dormancy was reversed by one week of dark incubation at 30C. This warm incubation treatment also reduced the light requirement of unchilled, after-ripened seed. Fluctuations in dormancy and light requirement of buried seeds have been linked to seasonal changes in soil temperature. Penstemon palmeri germination responses to temperature appear to be similar to those of facultative winter annuals.

  17. RNA-Seq transcriptome analysis of Spirodela dormancy without reproduction

    PubMed Central

    2014-01-01

    Background Higher plants exhibit a remarkable phenotypic plasticity to adapt to adverse environmental changes. The Greater Duckweed Spirodela, as an aquatic plant, presents exceptional tolerance to cold winters through its dormant structure of turions in place of seeds. Abundant starch in turions permits them to sink and escape the freezing surface of waters. Due to their clonal propagation, they are the fastest growing biomass on earth, providing yet an untapped source for industrial applications. Results We used next generation sequencing technology to examine the transcriptome of turion development triggered by exogenous ABA. A total of 208 genes showed more than a 4-fold increase compared with 154 down-regulated genes in developing turions. The analysis of up-regulated differential expressed genes in response to dormancy exposed an enriched interplay among various pathways: signal transduction, seed dehydration, carbohydrate and secondary metabolism, and senescence. On the other side, the genes responsible for rapid growth and biomass accumulation through DNA assembly, protein synthesis and carbon fixation are repressed. Noticeably, three members of late embryogenesis abundant protein family are exclusively expressed during turion formation. High expression level of key genes in starch synthesis are APS1, APL3 and GBSSI, which could artificially be reduced for re-directing carbon flow from photosynthesis to create a higher energy biomass. Conclusions The identification and functional annotation of differentially expressed genes open a major step towards understanding the molecular network underlying vegetative frond dormancy. Moreover, genes have been identified that could be engineered in duckweeds for practical applications easing agricultural production of food crops. PMID:24456086

  18. Cell Polarization and Cytokinesis in Budding Yeast

    PubMed Central

    Bi, Erfei; Park, Hay-Oak

    2012-01-01

    Asymmetric cell division, which includes cell polarization and cytokinesis, is essential for generating cell diversity during development. The budding yeast Saccharomyces cerevisiae reproduces by asymmetric cell division, and has thus served as an attractive model for unraveling the general principles of eukaryotic cell polarization and cytokinesis. Polarity development requires G-protein signaling, cytoskeletal polarization, and exocytosis, whereas cytokinesis requires concerted actions of a contractile actomyosin ring and targeted membrane deposition. In this chapter, we discuss the mechanics and spatial control of polarity development and cytokinesis, emphasizing the key concepts, mechanisms, and emerging questions in the field. PMID:22701052

  19. Essential Oil of Betula pendula Roth. Buds.

    PubMed

    Demirci, Betül; Paper, Dietrich H; Demirci, Fatih; Can Başer, K Hüsnü; Franz, Gerhard

    2004-12-01

    The essential oil of Betula pendula Roth. buds was obtained using both hydrodistillation and microdistillation techniques and their chemical compositions were analyzed using both gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS). Overall, more than 50 compounds were identified representing 80% and 92% for hydrodistillation and microdistillation, respectively. The main components (by hydrodistillation and microdistillation, respectively) found were alpha-copaene (12% and 10%), germacrene D (11% and 18%) and delta-cadinene (11% and 15%) in the analyzed essential oils. The microdistillation technique proved to be a useful tool and compliant alternative when compared to hydrodistillation. PMID:15841263

  20. Essential Oil of Betula pendula Roth. Buds

    PubMed Central

    2004-01-01

    The essential oil of Betula pendula Roth. buds was obtained using both hydrodistillation and microdistillation techniques and their chemical compositions were analyzed using both gas chromatography (GC) and gas chromatography–mass spectrometry (GC-MS). Overall, more than 50 compounds were identified representing 80% and 92% for hydrodistillation and microdistillation, respectively. The main components (by hydrodistillation and microdistillation, respectively) found were α-copaene (12% and 10%), germacrene D (11% and 18%) and δ-cadinene (11% and 15%) in the analyzed essential oils. The microdistillation technique proved to be a useful tool and compliant alternative when compared to hydrodistillation. PMID:15841263

  1. One phase of the dormancy developmental pathway is critical for the evolution of insect seasonality.

    PubMed

    Wadsworth, C B; Woods, W A; Hahn, D A; Dopman, E B

    2013-11-01

    Evolutionary change in the timing of dormancy enables animals and plants to adapt to changing seasonal environments and can result in ecological speciation. Despite its clear biological importance, the mechanisms underlying the evolution of dormancy timing in animals remain poorly understood because of a lack of anatomical landmarks to discern which phase of dormancy an individual is experiencing. Taking advantage of the nearly universal characteristic of metabolic suppression during insect dormancy (diapause), we use patterns of respiratory metabolism to document physiological landmarks of dormancy and test which of the distinct phases of the dormancy developmental pathway contribute to a month-long shift in diapause timing between a pair of incipient moth species. Here, we show that divergence in life cycle between the earlier-emerging E-strain and the later-emerging Z-strain of European corn borer (ECB) is clearly explained by a delay in the timing of the developmental transition from the diapause maintenance phase to the termination phase. Along with recent findings indicating that life-cycle differences between ECB strains stem from allelic variation at a single sex-linked locus, our results demonstrate how dramatic shifts in animal seasonality can result from simple developmental and genetic changes. Although characterizing the multiple phases of the diapause developmental programme in other locally adapted populations and species will undoubtedly yield surprises about the nature of animal dormancy, results in the ECB moth suggest that focusing on genetic variation in the timing of the dormancy termination phase may help explain how (or whether) organisms rapidly respond to global climate change, expand their ranges after accidental or managed introductions, undergo seasonal adaptation, or evolve into distinct species through allochronic isolation. PMID:24016035

  2. Trade-offs between seed dispersal and dormancy in an amphi-basicarpic cold desert annual

    PubMed Central

    Lu, Juan J.; Tan, Dun Y.; Baskin, Jerry M.; Baskin, Carol C.

    2013-01-01

    Background and Aims Several studies have demonstrated trade-offs between depth of seed dormancy and dispersal ability for diaspore-dimorphic species. However, relatively little is known about trade-offs between these two life history traits for a species that produces more than two diaspore morphs. The aim of this study was to investigate the relationship between seed dormancy and dispersal in Ceratocarpus arenarius, an amphi-basicarpic cold desert annual that produces a continuum of dispersal unit morphs. Methods A comparison was made of dispersal and dormancy breaking/germination responses of dispersal units from ground level (a), the middle of the plant canopy (c) and the top of the plant canopy (f). Various features of the morphology and mass of dispersal units and fruits (utricles) were measured. The role of bracteoles in diaspore dispersal by wind, settlement onto the soil surface and dormancy/germination was determined by comparing responses of intact dispersal units and fruits. Movement of dispersal units by wind and animals, seed after-ripening, germination phenology and the presence of water-soluble germination inhibitors in bracteoles were tested using standard procedures. Key Results Dispersal units a, c and f differed in morphology and mass; in the majority of cases, extremes were exhibited by a and f, with c being intermediate. Overall, relative dispersal ability was f > c > a, whereas relative intensity of dormancy was a > c > f. Bracteoles increased dispersal distance by wind, enhanced settlement of diaspores onto the soil surface and mechanically inhibited germination. Conclusions The results provide evidence for a model in which there is a continuous inverse-linear relationship between diaspore dispersal ability and depth of dormancy. Thus, dispersal unit heteromorphism of C. arenarius results in a continuum, from no dispersal ability/high dormancy (dispersal unit a) to high dispersal ability/low dormancy (unit f), which may be a bet-hedging strategy in the cold desert environment. PMID:24197752

  3. [Furcation entrance dimension, divergent angle and length of CEJ to furcation entrance relate to periodontal therapy].

    PubMed

    Hou, G L; Chen, S F; Tsai, C C

    1996-12-01

    In previous studies we have investigated the furcation entrance dimension (FED), furcation entrance angle (FEA) and the distance between cementoenamel junction and furcation entrance (CEJ-FE) of the first and second molars and compared the Chinese with the Caucasians. The aim of the present study was to relate the FED, FEA, and distance of CEJ-FE to the clinical significance of periodontal therapy of molar furcations. All the FEDs, FEAs, and distance of CEJ-FEs of the molars were measured by a stereomicroscope equipped with a Bioscan OPTIMAS Image Analyzer and statistically analyzed by Student's paired t-test, multiple regression of ANOVA and correlation analysis. The results are summarized below. (1) There is a significant relationship between FEA and location of buccal, mesial, and distal furcations of maxillary first and second molars (16& 26, p < 0.001; 17&27, p < 0.01). (2) There exists a significant relationship between FEA and FED in the mandibular first and second molars. (3) There exists a significant relationship between FED and FEA in the mandibular second molar (r = 0.370, p < 0.05). (4) The prevalence of mean FED and FEA (type D, FED < or = 0.75 mm and FEA < or = 90 degree) of the maxillary first molar (45%) is twice as high as the maxillary first molar (24%). (5) The prevalence of type D of the buccal (32%) and lingual (37%) furcations on the mandibular second molar is markedly higher than the first molar (buccal = 12%; lingual = 4%, respectively). These results reveal that those topographics of the FED, FEA, and distance of CEJ-FE in second molars have poor prognosis in periodontal therapy when compared with first molars. PMID:9011129

  4. Transcriptional changes induced by the tumor dormancy-associated microRNA-190

    PubMed Central

    Almog, Nava; Briggs, Christine; Beheshti, Afshin; Ma, Lili; Wilkie, Kathleen P.; Rietman, Edward; Hlatky, Lynn

    2013-01-01

    Tumor dormancy is a highly prevalent stage in cancer progression. We have previously generated and characterized in vivo experimental models of human tumor dormancy in which micro-tumors remain occult until they spontaneously shift into rapid tumor growth. We showed that the dormant micro-tumors undergo a stable microRNA (miRNA) switch during their transition from dormancy to a fast-growing phenotype and reported the identification of a consensus signature of human tumor dormancy-associated miRNAs (DmiRs). miRNA-190 (miR-190) is among the most upregulated DmiRs in all dormant tumors analyzed. Upregulation of miR-190 led to prolonged tumor dormancy in otherwise fast-growing glioblastomas and osteosarcomas. Here we investigate the transcriptional changes induced by miR-190 expression in cancer cells and show similar patterns of miR-190 mediated transcriptional reprogramming in both glioblastoma and osteosarcoma cells. The data suggests that miR-190 mediated effects rely on an extensive network of molecular changes in tumor cells and that miR-190 affects several transcriptional factors, tumor suppressor genes and interferon response pathways. The molecular mechanisms governing tumor dormancy described in this work may provide promising targets for early prevention of cancer and may lead to novel treatments to convert the malignant tumor phenotype into an asymptomatic dormant state. PMID:23863200

  5. Multiple loci and epistases control genetic variation for seed dormancy in weedy rice (Oryza sativa).

    PubMed Central

    Gu, Xing-You; Kianian, Shahryar F; Foley, Michael E

    2004-01-01

    Weedy rice has much stronger seed dormancy than cultivated rice. A wild-like weedy strain SS18-2 was selected to investigate the genetic architecture underlying seed dormancy, a critical adaptive trait in plants. A framework genetic map covering the rice genome was constructed on the basis of 156 BC(1) [EM93-1 (nondormant breeding line)//EM93-1/SS18-2] individuals. The mapping population was replicated using a split-tiller technique to control and better estimate the environmental variation. Dormancy was determined by germination of seeds after 1, 11, and 21 days of after-ripening (DAR). Six dormancy QTL, designated as qSD(S)-4, -6, -7-1, -7-2, -8, and -12, were identified. The locus qSD(S)-7-1 was tightly linked to the red pericarp color gene Rc. A QTL x DAR interaction was detected for qSD(S)-12, the locus with the largest main effect at 1, 11, and 21 DAR (R(2) = 0.14, 0.24, and 0.20, respectively). Two, three, and four orders of epistases were detected with four, six, and six QTL, respectively. The higher-order epistases strongly suggest the presence of genetically complex networks in the regulation of variation for seed dormancy in natural populations and make it critical to select for a favorable combination of alleles at multiple loci in positional cloning of a target dormancy gene. PMID:15082564

  6. Involvement of the ethylene response pathway in dormancy induction in chrysanthemum

    PubMed Central

    Sumitomo, Katsuhiko; Satoh, Shigeru; Hisamatsu, Tamotsu

    2008-01-01

    Temperature plays a significant role in the annual cycling between growth and dormancy of the herbaceous perennial chrysanthemum (Chrysanthemum morifolium Ramat.). After exposure to high summer temperatures, cool temperature triggers dormancy. The cessation of flowering and rosette formation by the cessation of elongation are characteristic of dormant plants, and can be stimulated by exogenous ethylene. Thus, the ethylene response pathway may be involved in temperature-induced dormancy of chrysanthemum. Transgenic chrysanthemums expressing a mutated ethylene receptor gene were used to assess this involvement. The transgenic lines showed reduced ethylene sensitivity: ethylene causes leaf yellowing in wild-type chrysanthemums, but leaves remained green in the transgenic lines. Extension growth and flowering of wild-type and transgenic lines varied between temperatures: at 20 °C, the transgenic lines showed the same stem elongation and flowering as the wild type; at cooler temperatures, the wild type formed rosettes with an inability to flower and entered dormancy, but some transgenic lines continued to elongate and flower. This supports the involvement of the ethylene response pathway in the temperature-induced dormancy of chrysanthemum. At the highest dosage of ethephon, an ethylene-releasing agent, wild-type plants formed rosettes with an inability to flower and became dormant, but one transgenic line did not. This confirms that dormancy is induced via the ethylene response pathway. PMID:18952907

  7. Environmental control of ovarian dormancy in natural populations of Drosophila melanogaster.

    PubMed

    Emerson, Kevin J; Uyemura, Alison M; McDaniel, Keely L; Schmidt, Paul S; Bradshaw, William E; Holzapfel, Christina M

    2009-09-01

    Drosophila melanogaster from Australia, Europe and North America enter an adult ovarian dormancy in response to short days and low temperatures. The independent effects of temperature and day length in the determination of dormancy have been examined only in one long-established laboratory line (Canton-S). In all other studies of natural or laboratory populations, dormancy has been assessed at either a single short day or a single moderately low temperature. Herein, we determine the relative roles of temperature, photoperiod, and their interaction in the control of ovarian dormancy in D. melanogaster from two natural populations representing latitudinal extremes in eastern North America (Florida at 27 degrees N and Maine at 44 degrees N). In both natural populations, temperature is the main determinant of dormancy, alone explaining 67% of the total variation among replicate isofemale lines, whereas photoperiod has no significant effect. We conclude that ovarian dormancy in D. melanogaster is a temperature-initiated syndrome of winter-tolerant traits that represents an adaptive phenotypic plasticity in temperate seasonal environments. PMID:19669646

  8. Analysis of natural allelic variation at seed dormancy loci of Arabidopsis thaliana.

    PubMed Central

    Alonso-Blanco, Carlos; Bentsink, Leónie; Hanhart, Corrie J; Blankestijn-de Vries, Hetty; Koornneef, Maarten

    2003-01-01

    Arabidopsis accessions differ largely in their seed dormancy behavior. To understand the genetic basis of this intraspecific variation we analyzed two accessions: the laboratory strain Landsberg erecta (Ler) with low dormancy and the strong-dormancy accession Cape Verde Islands (Cvi). We used a quantitative trait loci (QTL) mapping approach to identify loci affecting the after-ripening requirement measured as the number of days of seed dry storage required to reach 50% germination. Thus, seven QTL were identified and named delay of germination (DOG) 1-7. To confirm and characterize these loci, we developed 12 near-isogenic lines carrying single and double Cvi introgression fragments in a Ler genetic background. The analysis of these lines for germination in water confirmed four QTL (DOG1, DOG2, DOG3, and DOG6) as showing large additive effects in Ler background. In addition, it was found that DOG1 and DOG3 genetically interact, the strong dormancy determined by DOG1-Cvi alleles depending on DOG3-Ler alleles. These genotypes were further characterized for seed dormancy/germination behavior in five other test conditions, including seed coat removal, gibberellins, and an abscisic acid biosynthesis inhibitor. The role of the Ler/Cvi allelic variation in affecting dormancy is discussed in the context of current knowledge of Arabidopsis germination. PMID:12807791

  9. The qSD12 Locus Controls Offspring Tissue-Imposed Seed Dormancy in Rice

    PubMed Central

    Gu, Xing-You; Turnipseed, E. Brent; Foley, Michael E.

    2008-01-01

    Seed component structures were grouped into maternal and offspring (embryo and endosperm) tissues to characterize a dormancy quantitative trait locus (QTL) for tissue-specific function using a marker-assisted genetic approach. The approach was devised to test if genotypic/allelic frequencies of a marker tightly linked to the QTL deviate from Mendelian expectations in germinated and nongerminated subpopulations derived from a segregation population of partially after-ripened seeds and was applied to the dormancy QTL qSD12 and qSD7-1 in a nearly isogenic background of rice. Experimental results unambiguously demonstrated that qSD12 functions in the offspring tissue(s) and suggested that qSD7-1 may control dormancy through the maternal tissues. These experiments also provide the first solid evidence that an offspring tissue-imposed dormancy gene contributes to the segregation distortion in a mapping population developed from partially after-ripened seeds and, in part, to the germination heterogeneity of seeds from hybrid plants. Offspring and maternal tissue-imposed dormancy genes express in very early and late stages of the life cycle, respectively, and interact to provide the species with complementary adaptation strategies. The qSD12 locus was narrowed to the region of ∼600 kbp on a high-resolution map to facilitate cloning and marker-assisted selection of the major dormancy gene. PMID:18711220

  10. Map-Based Cloning of Seed Dormancy1-2 Identified a Gibberellin Synthesis Gene Regulating the Development of Endosperm-Imposed Dormancy in Rice.

    PubMed

    Ye, Heng; Feng, Jiuhuan; Zhang, Lihua; Zhang, Jinfeng; Mispan, Muhamad S; Cao, Zhuanqin; Beighley, Donn H; Yang, Jianchang; Gu, Xing-You

    2015-11-01

    Natural variation in seed dormancy is controlled by multiple genes mapped as quantitative trait loci in major crop or model plants. This research aimed to clone and characterize the Seed Dormancy1-2 (qSD1-2) locus associated with endosperm-imposed dormancy and plant height in rice (Oryza sativa). qSD1-2 was delimited to a 20-kb region, which contains OsGA20ox2 and had an additive effect on germination. Naturally occurring or induced loss-of-function mutations of the gibberellin (GA) synthesis gene enhanced seed dormancy and also reduced plant height. Expression of this gene in seeds (including endospermic cells) during early development increased GA accumulation to promote tissue morphogenesis and maturation programs. The mutant allele prevalent in semidwarf cultivars reduced the seed GA content by up to 2-fold at the early stage, which decelerated tissue morphogenesis including endosperm cell differentiation, delayed abscisic acid accumulation by a shift in the temporal distribution pattern, and postponed dehydration, physiological maturity, and germinability development. As the endosperm of developing seeds dominates the moisture equilibrium and desiccation status of the embryo in cereal crops, qSD1-2 is proposed to control primary dormancy by a GA-regulated dehydration mechanism. Allelic distribution of OsGA20ox2, the rice Green Revolution gene, was associated with the indica and japonica subspeciation. However, this research provided no evidence that the primitive indica- and common japonica-specific alleles at the presumably domestication-related locus functionally differentiate in plant height and seed dormancy. Thus, the evolutionary mechanism of this agriculturally important gene remains open for discussion. PMID:26373662

  11. Dormancy effects on the reliability of nuclear thermal propulsion systems for long-term manned space missions

    SciTech Connect

    Shooman, M.L.; Sforza, P.M. )

    1993-01-10

    This paper explores the effects of dormancy on the reliability of a Nuclear Thermal Propulsion (NTP) system for long-term manned space missions, such as Mars exploration. Dormancy refers to the portion of space systems operation where the power and stress levels are significantly reduced from nominal values and the authors have identified dormancy as a significant effect. Three approaches are used to evaluate the relative importance of failure rates during dormant operation: use of failure rate models involving dormancy, power cycling and fully energized operation; study of data bases which include both dormant and energized failure rates; predictions based on an Arrhenius rate process formulation. The results of these approaches suggest that for a long term manned mission the dormancy, cycle, and energized failure rates will all be important. Reliability in the energized state normally receives utmost attention and care during design, however, unless equal attention is directed to dormancy, the mission reliability may be severely compromised.

  12. The relativistic titls of Giza pyramids' entrance-passages

    NASA Astrophysics Data System (ADS)

    Aboulfotouh, H.

    The tilts of Giza pyramids' entrance-passages have never been considered as if they were the result of relativistic mathematical equations, and never been thought to encode the Earth's obliquity parameters. This paper presents an attempt to retrieve the method of establishing the equations that the pyramids' designer used to quantify the entrance-passages' tilts of these architectonic masterpieces. It proves that the pyramids' designer was able to include the geographic, astronomical and time parameters in one relativistic equation, encoding the date of the design of the Giza pyramids in the tilt of the entrance passage of the great pyramid.

  13. Electrochemical Regulation of Budding Yeast Polarity

    PubMed Central

    Piel, Matthieu; Chang, Fred; Minc, Nicolas

    2014-01-01

    Cells are naturally surrounded by organized electrical signals in the form of local ion fluxes, membrane potential, and electric fields (EFs) at their surface. Although the contribution of electrochemical elements to cell polarity and migration is beginning to be appreciated, underlying mechanisms are not known. Here we show that an exogenous EF can orient cell polarization in budding yeast (Saccharomyces cerevisiae) cells, directing the growth of mating projections towards sites of hyperpolarized membrane potential, while directing bud emergence in the opposite direction, towards sites of depolarized potential. Using an optogenetic approach, we demonstrate that a local change in membrane potential triggered by light is sufficient to direct cell polarization. Screens for mutants with altered EF responses identify genes involved in transducing electrochemical signals to the polarity machinery. Membrane potential, which is regulated by the potassium transporter Trk1p, is required for polarity orientation during mating and EF response. Membrane potential may regulate membrane charges through negatively charged phosphatidylserines (PSs), which act to position the Cdc42p-based polarity machinery. These studies thus define an electrochemical pathway that directs the orientation of cell polarization. PMID:25548923

  14. Crystal structures of the Gon7/Pcc1 and Bud32/Cgi121 complexes provide a model for the complete yeast KEOPS complex

    PubMed Central

    Zhang, Wenhua; Collinet, Bruno; Graille, Marc; Daugeron, Marie-Claire; Lazar, Noureddine; Libri, Domenico; Durand, Dominique; van Tilbeurgh, Herman

    2015-01-01

    The yeast KEOPS protein complex comprising Kae1, Bud32, Cgi121, Pcc1 and Gon7 is responsible for the essential tRNA threonylcarbamoyladenosine (t6A) modification. Deletion of genes coding for the KEOPS subunits also affects telomere elongation and transcriptional regulation. In the present work, the crystal structure of Bud32/Cgi121 in complex with ADP revealed that ADP is bound in the catalytic site of Bud32 in a canonical manner characteristic of Protein Kinase A (PKA) family proteins. We found that Gon7 forms a stable heterodimer with Pcc1 and report the crystal structure of the Pcc1-Gon7 heterodimer. Gon7 interacts with the same Pcc1 region engaged in the archaeal Pcc1 homodimer. We further show that yeast KEOPS, unlike its archaeal counterpart, exists as a heteropentamer in which Gon7, Pcc1, Kae1, Bud32 and Cgi121 also adopt a linear arrangement. We constructed a model of yeast KEOPS that provides structural insight into the role of Gon7. The model also revealed the presence of a highly positively charged crater surrounding the entrance of Kae1 that likely binds tRNA. PMID:25735745

  15. Tanned or Burned: The Role of Fire in Shaping Physical Seed Dormancy

    PubMed Central

    Moreira, Bruno; Pausas, Juli G.

    2012-01-01

    Plant species with physical seed dormancy are common in mediterranean fire-prone ecosystems. Because fire breaks seed dormancy and enhances the recruitment of many species, this trait might be considered adaptive in fire-prone environments. However, to what extent the temperature thresholds that break physical seed dormancy have been shaped by fire (i.e., for post-fire recruitment) or by summer temperatures in the bare soil (i.e., for recruitment in fire-independent gaps) remains unknown. Our hypothesis is that the temperature thresholds that break physical seed dormancy have been shaped by fire and thus we predict higher dormancy lost in response to fire than in response to summer temperatures. We tested this hypothesis in six woody species with physical seed dormancy occurring in fire-prone areas across the Mediterranean Basin. Seeds from different populations of each species were subject to heat treatments simulating fire (i.e., a single high temperature peak of 100°C, 120°C or 150°C for 5 minutes) and heat treatments simulating summer (i.e., temperature fluctuations; 30 daily cycles of 3 hours at 31°C, 4 hours at 43°C, 3 hours at 33°C and 14 hours at 18°C). Fire treatments broke dormancy and stimulated germination in all populations of all species. In contrast, summer treatments had no effect over the seed dormancy for most species and only enhanced the germination in Ulex parviflorus, although less than the fire treatments. Our results suggest that in Mediterranean species with physical dormancy, the temperature thresholds necessary to trigger seed germination are better explained as a response to fire than as a response to summer temperatures. The high level of dormancy release by the heat produced by fire might enforce most recruitment to be capitalized into a single post-fire pulse when the most favorable conditions occur. This supports the important role of fire in shaping seed traits. PMID:23227267

  16. 3. DETAIL OF ART DECO STAR INSIGNIA OVER MAIN ENTRANCE. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    3. DETAIL OF ART DECO STAR INSIGNIA OVER MAIN ENTRANCE. - Wright-Patterson Air Force Base, Area B, Building 65, Static Structural Test Laboratory, Between Eleventh & Twelfth Streets, Dayton, Montgomery County, OH

  17. 7. Light tower, interior from entrance, looking northwest Pumpkin ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    7. Light tower, interior from entrance, looking northwest - Pumpkin Island Light Station, Pumpkin Island, at northern end of Eggemoggin Beach, off northwest end of Little Deer Island, Eggemoggin, Hancock County, ME

  18. Detail view in caryatid breezeway to show entrance steps; lion ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Detail view in caryatid breezeway to show entrance steps; lion statues once flanked these steps - National Park Seminary, Aloha House, North of Linden Lane near corner of Beech Drive, Silver Spring, Montgomery County, MD

  19. Exterior view of southern half of east porch, showing entrance ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Exterior view of southern half of east porch, showing entrance to second story of la casa, view towards the west - Pou Coffee Processing Structure, Casa No. 2, Highway 139, Kilometer 12, Maraguez, Ponce Municipio, PR

  20. 9. MAGAZINE P INTERIOR, LOOKING TO DOORWAY ENTRANCE. NIKE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    9. MAGAZINE P INTERIOR, LOOKING TO DOORWAY ENTRANCE. - NIKE Missile Base C-84, Underground Storage Magazines & Launcher-Loader Assemblies, Easternmost portion of launch area, Barrington, Cook County, IL

  1. 2. MAGAZINE P, WITH ENTRANCE DOOR IN FOREGROUND, LOOKING NORTHEAST. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. MAGAZINE P, WITH ENTRANCE DOOR IN FOREGROUND, LOOKING NORTHEAST. - NIKE Missile Base C-84, Underground Storage Magazines & Launcher-Loader Assemblies, Easternmost portion of launch area, Barrington, Cook County, IL

  2. 47. INTERIOR, FIRST FLOOR, ENTRANCE HALL, DETAIL OF NEWEL POST ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    47. INTERIOR, FIRST FLOOR, ENTRANCE HALL, DETAIL OF NEWEL POST WITH LAMPS FROM THE NORTH - Mark Twain House, 351 Farmington Avenue (corrected from original address of 531 Farmington Avenue), Hartford, Hartford County, CT

  3. 48. INTERIOR, FIRST FLOOR, ENTRANCE HALL, DETAIL OF BUST OF ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    48. INTERIOR, FIRST FLOOR, ENTRANCE HALL, DETAIL OF BUST OF SAMUEL CLEMENTS AND WALL STENCILING - Mark Twain House, 351 Farmington Avenue (corrected from original address of 531 Farmington Avenue), Hartford, Hartford County, CT

  4. 46. INTERIOR, FIRST FLOOR, ENTRANCE HALL, VIEW OF STAIRCASE IN ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    46. INTERIOR, FIRST FLOOR, ENTRANCE HALL, VIEW OF STAIRCASE IN SOUTHWEST CORNER FROM THE NORTH - Mark Twain House, 351 Farmington Avenue (corrected from original address of 531 Farmington Avenue), Hartford, Hartford County, CT

  5. 141. GATE AT ORIGINAL ENTRANCE TO MT. VERNON LOCATED ON ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    141. GATE AT ORIGINAL ENTRANCE TO MT. VERNON LOCATED ON OLD MT. VERNON RD. LOOKING EAST. - George Washington Memorial Parkway, Along Potomac River from McLean to Mount Vernon, VA, Mount Vernon, Fairfax County, VA

  6. 15. DETAIL, MAIN FACADE, ENTRANCE PORCH, STONE BEARING ARCHITECT'S NAME ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    15. DETAIL, MAIN FACADE, ENTRANCE PORCH, STONE BEARING ARCHITECT'S NAME AS SEEN THROUGH SIDE ARCHED OPENING - U.S. Soldiers Home, Scott Building, Rock Creek Church Road & Upshur Street Northwest, Washington, District of Columbia, DC

  7. 22. CLOSEUP OF BUNKER ENTRANCE WITH WORK CREW PREPARING TO ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    22. CLOSEUP OF BUNKER ENTRANCE WITH WORK CREW PREPARING TO MOVE DUMPSTER. CAMERA FACING EAST. INEL PHOTO NUMBER 79-7187. PHOTOGRAPHER NOT NAMED. - Idaho National Engineering Laboratory, Advanced Reentry Vehicle Fusing System, Scoville, Butte County, ID

  8. 70. Smart view recreation area entrance road. View of the ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    70. Smart view recreation area entrance road. View of the snake or worm fences used to reinforce the roadway alignment. Looking north-northwest. - Blue Ridge Parkway, Between Shenandoah National Park & Great Smoky Mountains, Asheville, Buncombe County, NC

  9. 35. Basement, passage beneath main entrance porch, showing circular skylight ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    35. Basement, passage beneath main entrance porch, showing circular skylight opening, view to northwest - Portsmouth Naval Hospital, Hospital Building, Rixey Place, bounded by Williamson Drive, Holcomb Road, & The Circle, Portsmouth, Portsmouth, VA

  10. 5. Keeper's house, detail of entrance porch, southeast corner, looking ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    5. Keeper's house, detail of entrance porch, southeast corner, looking northwest - Ram Island Light Station, Ram Island, south of Ocean Point & just north of Fisherman Island, marking south side of Fisherman Island Passage, Ocean Point, Lincoln County, ME

  11. 1. VIEW OF THE ENTRANCE TO THE HATCH ADIT (FEATURE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. VIEW OF THE ENTRANCE TO THE HATCH ADIT (FEATURE B-28), FACING WEST. (OCTOBER, 1995) - Nevada Lucky Tiger Mill & Mine, Hatch Adit, East slope of Buckskin Mountain, Paradise Valley, Humboldt County, NV

  12. 4. SULLIVAN TAILING PILE. CAMERA POINTED WEST. MINE ENTRANCE IS ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. SULLIVAN TAILING PILE. CAMERA POINTED WEST. MINE ENTRANCE IS APPROXIMATELY 30 YARDS BEHIND CAMERA POSITION. - Florida Mountain Mining Sites, Sullivan Mine, East side of Florida Mountain, Silver City, Owyhee County, ID

  13. 5. View of Community Hall, first floor interior, entrance hall ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    5. View of Community Hall, first floor interior, entrance hall on east side of building, facing southeast. Ticket booth center foreground, stairway to auditorium right foreground. - Community Hall, Rainier Avenue & View Drive, Port Gamble, Kitsap County, WA

  14. 118. BENCH SHOP, NORTHWEST CORNER SHOWING ENTRANCE TO ROOM FROM ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    118. BENCH SHOP, NORTHWEST CORNER SHOWING ENTRANCE TO ROOM FROM OUTSIDE. OFFICE SAFE AT CENTER. - Gruber Wagon Works, Pennsylvania Route 183 & State Hill Road at Red Bridge Park, Bernville, Berks County, PA

  15. 2. HISTORIC AMERICAN BUILDINGS SURVEY. S. Lucas, Photographer, 1934 ENTRANCE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. HISTORIC AMERICAN BUILDINGS SURVEY. S. Lucas, Photographer, 1934 ENTRANCE DETAIL, SS. PETER & PAUL'S JESUIT CHURCH, DETROIT MICHIGAN - Sts. Peter & Paul's Jesuit Church, East Jefferson Avenue & Saint Antoine Street, Detroit, Wayne County, MI

  16. 108. Photocopy of frontispiece in Owen, Hints. MAIN ENTRANCE, NORTH ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    108. Photocopy of frontispiece in Owen, Hints. MAIN ENTRANCE, NORTH FRONT, SMITHSONIAN INSTITUTION - Smithsonian Institution Building, 1000 Jefferson Drive, between Ninth & Twelfth Streets, Southwest, Washington, District of Columbia, DC

  17. North & south wall elevation of the east entrance loggia; ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    North & south wall elevation of the east entrance loggia; detail of pilaster base and capital - National Zoological Park, Elephant House, 3001 Connecticut Avenue NW, Washington, District of Columbia, DC

  18. 1. GENERAL VIEW OF ENTRANCE INTO ALUMINUM CITY TERRACE ALONG ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. GENERAL VIEW OF ENTRANCE INTO ALUMINUM CITY TERRACE ALONG EAST HILL DRIVE. BUILDING 1 ON RIGHT, BUILDING 2 ON LEFT, FACING EAST. - Aluminum City Terrace, East Hill Drive, New Kensington, Westmoreland County, PA

  19. 53. INTERIOR, FIRST FLOOR, SOUTH ENTRANCE, SOUTH LOBBY, DETAIL OF ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    53. INTERIOR, FIRST FLOOR, SOUTH ENTRANCE, SOUTH LOBBY, DETAIL OF DOOR PULLS FOR AUDITORIUM (CONFERENCE HALL) DOOR - U.S. Department of the Interior, Eighteenth & C Streets Northwest, Washington, District of Columbia, DC

  20. 52. INTERIOR, FIRST FLOOR, SOUTH ENTRANCE, SOUTH LOBBY, AUDITORIUM (CONFERENCE ...

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    52. INTERIOR, FIRST FLOOR, SOUTH ENTRANCE, SOUTH LOBBY, AUDITORIUM (CONFERENCE HALL) DOOR (4' x 5' negative; 8' x 10' print) - U.S. Department of the Interior, Eighteenth & C Streets Northwest, Washington, District of Columbia, DC

  1. 54. INTERIOR, FIRST FLOOR, SOUTH ENTRANCE, SOUTH LOBBY, DETAIL OF ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    54. INTERIOR, FIRST FLOOR, SOUTH ENTRANCE, SOUTH LOBBY, DETAIL OF PUSH PLATES FOR AUDITORIUM (CONFERENCE HALL) DOOR - U.S. Department of the Interior, Eighteenth & C Streets Northwest, Washington, District of Columbia, DC

  2. 7. STRUCTURAL DETAILS AT ENTRANCE OF LOCOMOTIVE ROUNDHOUSE, SHEET NO. ...

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    7. STRUCTURAL DETAILS AT ENTRANCE OF LOCOMOTIVE ROUNDHOUSE, SHEET NO. 1-9-2/89.1 (DRAWING DATED 1942). - Oakland Army Base, Railroad Engine Shop, Engineer Road & Wake Avenue, Oakland, Alameda County, CA

  3. 4. VIEW OF ENTRANCE TO BUILDING NO. 1 FACING WEST. ...

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    4. VIEW OF ENTRANCE TO BUILDING NO. 1 FACING WEST. - U.S. Naval Base, Pearl Harbor, Ordinance Operations Building, West Loch, First Street near Whiskey Wharves W1 & W2, Pearl City, Honolulu County, HI

  4. 2. DETAIL, EAST ENTRANCE, SHOWING OUTER BLAST DOOR AND INNER ...

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    2. DETAIL, EAST ENTRANCE, SHOWING OUTER BLAST DOOR AND INNER DOORS. - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Instrumentation & Control Building, Test Area 1-115, northwest end of Saturn Boulevard, Boron, Kern County, CA

  5. 39. ENTRANCE SIGN AT BEGINNING OF ARROYO SECO PARKWAY IN ...

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    39. ENTRANCE SIGN AT BEGINNING OF ARROYO SECO PARKWAY IN PASADENA AT INTERSECTION OF ARROYO SECO PARKWAY AND WALLIS ST. LOOKING 130 SE. - Arroyo Seco Parkway, Los Angeles to Pasadena, Los Angeles, Los Angeles County, CA

  6. Security Station and Front Entrance to hospital property, looking northeast ...

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    Security Station and Front Entrance to hospital property, looking northeast - U.S. Veterans Hospital, Jefferson Barracks, Security Station & Front Gate, VA Medical Center, Jefferson Barracks Division 1 Jefferson Barracks Drive, Saint Louis, Independent City, MO

  7. 14. Inner double blast door entrance to perimeter acquisition radar ...

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    14. Inner double blast door entrance to perimeter acquisition radar building security area - Stanley R. Mickelsen Safeguard Complex, Perimeter Acquisition Radar Building, Limited Access Area, between Limited Access Patrol Road & Service Road A, Nekoma, Cavalier County, ND

  8. 16. INTERIOR VIEW OF WINDOWS ABOVE MAIN ENTRANCE ON WEST ...

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    16. INTERIOR VIEW OF WINDOWS ABOVE MAIN ENTRANCE ON WEST ELEVATION. THE WINDOWS ARE HINGED AT THE BOTTOM AND OPEN INWARD - Kodiak Naval Operating Base, Gymnasium, U.S. Coast Guard Station, Kodiak, Kodiak Island Borough, AK

  9. 50. Fourth floor attic, paneled door opening at entrance to ...

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    50. Fourth floor attic, paneled door opening at entrance to surgeon's washroom, view to east - Portsmouth Naval Hospital, Hospital Building, Rixey Place, bounded by Williamson Drive, Holcomb Road, & The Circle, Portsmouth, Portsmouth, VA

  10. 1. Roaring Fork Motor Nature Trail, entrance sign. Great ...

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    1. Roaring Fork Motor Nature Trail, entrance sign. - Great Smoky Mountains National Park Roads & Bridges, Roaring Fork Motor Nature Trail, Between Cherokee Orchard Road & U.S. Route 321, Gatlinburg, Sevier County, TN

  11. 1. GENERAL VIEW OF SOUTH SIDE ELEVATION FROM ENTRANCE GATE, ...

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    1. GENERAL VIEW OF SOUTH SIDE ELEVATION FROM ENTRANCE GATE, WITH NEW CHURCH ON RIGHT - Valley Grove Churches, Old Church, County Road 29, 1/4 mile from Minnesota Highway 246, Nerstrand, Rice County, MN

  12. FEATURE D, TYPE 1 PILLBOX, NORTH SIDE SHOWING ENTRANCE MOSTLY ...

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    FEATURE D, TYPE 1 PILLBOX, NORTH SIDE SHOWING ENTRANCE MOSTLY BURIED IN SAND, VIEW FACING SOUTHEAST. - Naval Air Station Barbers Point, Shore Pillbox Complex-Type 1 Pillbox, Along shoreline, seaward of Coral Sea Road, Ewa, Honolulu County, HI

  13. 12. Cades Cove Road, view toward entrance with ruts in ...

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    12. Cades Cove Road, view toward entrance with ruts in road. - Great Smoky Mountains National Park Roads & Bridges, Cades Cove Road & Laurel Creek Road, From Townsend Wye to Cades Cove, Gatlinburg, Sevier County, TN

  14. 3. Perspective view of west entrance to Gas House. ...

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    3. Perspective view of west entrance to Gas House. - Delaware, Lackawanna & Western Railroad, Scranton Yards, Gas House, 100 block of South Washington Avenue, west side, Scranton, Lackawanna County, PA

  15. 38. STAIRS FROM ENTRANCE AT SIXTEENTH STREET TO UPPER MALL ...

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    38. STAIRS FROM ENTRANCE AT SIXTEENTH STREET TO UPPER MALL PARK, LOOKING SOUTH, summer 1985 - Meridian Hill Park, Bounded by Fifteenth, Sixteenth, Euclid & W Streets, Northwest, Washington, District of Columbia, DC

  16. 37. STAIRS TO ENTRANCE AT SIXTEENTH STREET FROM UPPER MALL ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    37. STAIRS TO ENTRANCE AT SIXTEENTH STREET FROM UPPER MALL PARK, LOOKING NORTH, August 1976 - Meridian Hill Park, Bounded by Fifteenth, Sixteenth, Euclid & W Streets, Northwest, Washington, District of Columbia, DC

  17. 38. JL photographer, summer 1978, general view of main entrance ...

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    38. JL photographer, summer 1978, general view of main entrance facade of Baldwin Filtration plant. - Division Avenue Pumping Station & Filtration Plant, West 45th Street and Division Avenue, Cleveland, Cuyahoga County, OH

  18. 84. INTERIOR, SECOND FLOOR, NORTH ENTRANCE, NORTH LOBBY, NORTH WALL, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    84. INTERIOR, SECOND FLOOR, NORTH ENTRANCE, NORTH LOBBY, NORTH WALL, BRONZE DOUBLE DOORS (4' x 5' negative; 8' x 10' print) - U.S. Department of the Interior, Eighteenth & C Streets Northwest, Washington, District of Columbia, DC

  19. 27. INTERIOR, FIRST FLOOR, SOUTH ENTRANCE, SOUTH LOBBY, DETAIL OF ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    27. INTERIOR, FIRST FLOOR, SOUTH ENTRANCE, SOUTH LOBBY, DETAIL OF BRONZE SEAL IN FLOOR (4' x 5' negative; 8' x 10' print) - U.S. Department of the Interior, Eighteenth & C Streets Northwest, Washington, District of Columbia, DC

  20. 25. INTERIOR, FIRST FLOOR, SOUTH ENTRANCE, LOBBY, DETAIL OF BRONZE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    25. INTERIOR, FIRST FLOOR, SOUTH ENTRANCE, LOBBY, DETAIL OF BRONZE AND GLASS DOORS (4' x 5' negative; 8' x 10' print) - U.S. Department of the Interior, Eighteenth & C Streets Northwest, Washington, District of Columbia, DC

  1. 17. DETAILED VIEW OF THE ENTRANCE OF THE COTTON WOOD ...

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    17. DETAILED VIEW OF THE ENTRANCE OF THE COTTON WOOD PRESSURE PIPE Photographer: Walter J. Lubken, March 9, 1906 - Roosevelt Power Canal & Diversion Dam, Parallels Salt River, Roosevelt, Gila County, AZ

  2. Detail of window and lamp at entrance on north side ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Detail of window and lamp at entrance on north side of north wing; camera facing south. - Mare Island Naval Shipyard, Administrative Offices, Walnut Avenue, east side between Seventh & Eighth Streets, Vallejo, Solano County, CA

  3. DETAIL OF LAMP ABOVE SOUTH SIDE ENTRANCE; CAMERA FACING EAST ...

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    DETAIL OF LAMP ABOVE SOUTH SIDE ENTRANCE; CAMERA FACING EAST - Mare Island Naval Shipyard, Bachelor Enlisted Quarters & Offices, Walnut Avenue, east side between D Street & C Street, Vallejo, Solano County, CA

  4. 9. DETAIL OF REAR ENTRANCE ON EAST WALL OF NORTH ...

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    9. DETAIL OF REAR ENTRANCE ON EAST WALL OF NORTH WING OF BUILDING. VIEW TO NORTHWEST. - Fort David A. Russell, Red Cross Building, Third Street between Randall Avenue & Tenth Cavalry Avenue, Cheyenne, Laramie County, WY

  5. 72. Detail of keystone emblem over the main entrance to ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    72. Detail of keystone emblem over the main entrance to the Carpenter's Union Hall. The inscription translates 'Labor conquers all.' - Butte Historic District, Bounded by Copper, Arizona, Mercury & Continental Streets, Butte, Silver Bow County, MT

  6. 15. ROOMS 48 AND 49, LOOKING SOUTH FROM ENTRANCE TO ...

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    15. ROOMS 48 AND 49, LOOKING SOUTH FROM ENTRANCE TO ROOM 47. THE OAK CABINETS ARE USED TO STORE ROCK CORE SAMPLES. - U.S. Geological Survey, Rock Magnetics Laboratory, 345 Middlefield Road, Menlo Park, San Mateo County, CA

  7. View from western bridge portal along entrance road, softball fields ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    View from western bridge portal along entrance road, softball fields to right and hospital complex in distance - New York State Soldiers & Sailors Home, Department of Veterans Affairs Medical Center, 76 Veterans Avenue, Bath, Steuben County, NY

  8. Interior view, stairwell and entrance to the great hall (note ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Interior view, stairwell and entrance to the great hall (note Boardman Roberts's painting, Great Codifers of Law) - United States Department of Justice, Constitution Avenue between Ninth & Tenth Streets, Northwest, Washington, District of Columbia, DC

  9. 24. LAUNCH CONTROL CAPSULE. ENTRANCE TO ACOUSTICAL ENCLOSURE. SHOCK ISOLATOR ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    24. LAUNCH CONTROL CAPSULE. ENTRANCE TO ACOUSTICAL ENCLOSURE. SHOCK ISOLATOR AT FAR LEFT. VIEW TO NORTH. - Minuteman III ICBM Launch Control Facility November-1, 1.5 miles North of New Raymer & State Highway 14, New Raymer, Weld County, CO

  10. VIEW OF RIDING STABLE AND PASTURE FROM ENTRANCE ROAD, PART ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    VIEW OF RIDING STABLE AND PASTURE FROM ENTRANCE ROAD, PART TWO OF PANORAMA, FACING NORTHEAST - Overhills, Fort Bragg Military Reservation, Approximately 15 miles NW of Fayetteville, Overhills, Harnett County, NC

  11. 79. DETAIL, MOSAIC FLOOR IN HALL 355 AT ENTRANCE TO ...

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    79. DETAIL, MOSAIC FLOOR IN HALL 355 AT ENTRANCE TO REGENTS' ROOM, THIRD FLOOR - Smithsonian Institution Building, 1000 Jefferson Drive, between Ninth & Twelfth Streets, Southwest, Washington, District of Columbia, DC

  12. 3. FIRST FLOOR, FRONT ROOM WITH ENTRANCE DOORS ON THE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    3. FIRST FLOOR, FRONT ROOM WITH ENTRANCE DOORS ON THE EAST WALL - Penn School Historic District, Butler Building, SC Route 37, 1 mile South of Frogmore, St. Helena Island, Frogmore, Beaufort County, SC

  13. 1. VIEW WEST SOUTHWEST OF BUILDING 7 SHOWING MAIN ENTRANCE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. VIEW WEST SOUTHWEST OF BUILDING 7 SHOWING MAIN ENTRANCE TO OFFICES; MANAGEMENT AND FINANCE OFFICES WERE LOCATED HERE; BUILDING 23 IS AT RIGHT OF PHOTOGRAPH - Bryant Electric Company, 1421 State Street, Bridgeport, Fairfield County, CT

  14. 42. View near entrance to Dingle Basin, looking southwest. Photo ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    42. View near entrance to Dingle Basin, looking southwest. Photo by Brian C. Morris, Puget Power, 1989. - Puget Sound Power & Light Company, White River Hydroelectric Project, 600 North River Avenue, Dieringer, Pierce County, WA

  15. 67. View of old, abandoned vehicular bridge near entrance to ...

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    67. View of old, abandoned vehicular bridge near entrance to Lake Trapps. Photo by Brian C. Morris, Puget Power, 1989. - Puget Sound Power & Light Company, White River Hydroelectric Project, 600 North River Avenue, Dieringer, Pierce County, WA

  16. 3. View of entrance to cellar and heavy timber framing ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    3. View of entrance to cellar and heavy timber framing of the wine press building, looking southeast. - Merkel Farmstead, Wine Press Building, 8570 Louella Lane, south side of U.S. Route 64, Shiloh, St. Clair County, IL

  17. 5. BUILDING 0503, INTERIOR WOODEN ARCHES. Looking south from entrance. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    5. BUILDING 0503, INTERIOR WOODEN ARCHES. Looking south from entrance. - Edwards Air Force Base, South Base Sled Track, Earth Covered Bunker Types, North of Sled Track, Lancaster, Los Angeles County, CA

  18. EXTERIOR VIEW, LOOKING EAST, FRONT FACADE AND ENTRANCE TO COMPANY ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    EXTERIOR VIEW, LOOKING EAST, FRONT FACADE AND ENTRANCE TO COMPANY SCHOOL FOR CHILDREN OF BLACK TCI-US STEEL RED ORE MINE WORKERS - Company School for Blacks, 413 Morgan Road, Bessemer, Jefferson County, AL

  19. OBLIQUE VIEW OF FRONT SIDE (ENTRANCE) AND COURTYARD OF BUILDING ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    OBLIQUE VIEW OF FRONT SIDE (ENTRANCE) AND COURTYARD OF BUILDING 23, FACING SOUTHWEST - Roosevelt Base, Auditorium-Gymnasium, West Virginia Street between Richardson & Reeves Avenues, Long Beach, Los Angeles County, CA

  20. CONTROL BUILDING, WEST FRONT SHOWING ENTRANCE Edwards Air Force ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    CONTROL BUILDING, WEST FRONT SHOWING ENTRANCE - Edwards Air Force Base, X-15 Engine Test Complex, Firing Control Building, Rogers Dry Lake, east of runway between North Base & South Base, Boron, Kern County, CA

  1. VIEW OF TYPICAL SIDE DOOR ENTRANCE OF BUILDING 23, (AT ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    VIEW OF TYPICAL SIDE DOOR ENTRANCE OF BUILDING 23, (AT SOUTHWEST CORNER), FACING NORTH - Roosevelt Base, Auditorium-Gymnasium, West Virginia Street between Richardson & Reeves Avenues, Long Beach, Los Angeles County, CA

  2. VIEW OF FRONT SIDE (ENTRANCE) OF BUILDING 23, FROM MIDDLE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    VIEW OF FRONT SIDE (ENTRANCE) OF BUILDING 23, FROM MIDDLE OF COURTYARD, FACING WEST - Roosevelt Base, Auditorium-Gymnasium, West Virginia Street between Richardson & Reeves Avenues, Long Beach, Los Angeles County, CA

  3. VIEW OF LAMP FIXTURE (EXTERIOR) ADJACENT TO ENTRANCE AT SOUTHWEST ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    VIEW OF LAMP FIXTURE (EXTERIOR) ADJACENT TO ENTRANCE AT SOUTHWEST CORNER OF BUILDING 23, FACING NORTH - Roosevelt Base, Auditorium-Gymnasium, West Virginia Street between Richardson & Reeves Avenues, Long Beach, Los Angeles County, CA

  4. TENANT HOUSE INTERIOR, DOOR DETAIL, FRONT ENTRANCE INTO LIVING ROOM, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    TENANT HOUSE INTERIOR, DOOR DETAIL, FRONT ENTRANCE INTO LIVING ROOM, LOOKING NORTH - Irvine Ranch Agricultural Headquarters, Carillo Tenant House, Southwest of Intersection of San Diego & Santa Ana Freeways, Irvine, Orange County, CA

  5. View of stairway leading to west gallery from gallery entrance ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    View of stairway leading to west gallery from gallery entrance - U.S. Capitol, Old Senate Chamber, Intersection of North, South, & East Capitol Streets & Capitol Mall, Washington, District of Columbia, DC

  6. 8. WEST REAR, DETAIL SHOWING SECOND FLOOR ENTRANCE AND WINDOW ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    8. WEST REAR, DETAIL SHOWING SECOND FLOOR ENTRANCE AND WINDOW TREATMENT. See CA-174-B-22 FOR INTERIOR OF SECOND FLOOR LAB AT CENTER. - Hughes Aircraft Company, Engineering-Administration Building, 6775 Centinela Avenue, Los Angeles, Los Angeles County, CA

  7. 2. View of Ford Mansion looking at the front entrance ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. View of Ford Mansion looking at the front entrance with the fountain in the foreground - Richmond Hill Plantation, Ford Mansion, East of Richmond Hill on Ford Neck Road, Richmond Hill, Bryan County, GA

  8. 95. Pioneer Plaza, 125 (movie theater), entrance to theater and ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    95. Pioneer Plaza, 125 (movie theater), entrance to theater and building to left of theater - South El Paso Street Historic District, South El Paso, South Oregon & South Santa Fe Streets, El Paso, El Paso County, TX

  9. 14. DETAIL OF ENTRANCE OVERHANG, WEST SIDE OF NORTH PORTION. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    14. DETAIL OF ENTRANCE OVERHANG, WEST SIDE OF NORTH PORTION. SAME FEATURE AS A-13. - Chollas Heights Naval Radio Transmitting Facility, Transmitter Building, 6410 Zero Road, San Diego, San Diego County, CA

  10. 2. Water treatment plant entrance, view to W Fort ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. Water treatment plant entrance, view to W - Fort Benton Water Treatment Plant, Filtration Plant, Lots 9-13 of Block 7, Fort Benton Original Townsite at Missouri River, Fort Benton, Chouteau County, MT

  11. STAIRWAY OFF ENTRANCE LOBBY, PANELING TO LEFT ADDED IN 1995. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    STAIRWAY OFF ENTRANCE LOBBY, PANELING TO LEFT ADDED IN 1995. - Colt Fire Arms Company, East Armory Building, 36-150 Huyshope Avenue, 17-170 Van Dyke Avenue, 49 Vredendale Avenue, Hartford, Hartford County, CT

  12. 2. Deep Creek Road, old bridge at campground entrance. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. Deep Creek Road, old bridge at campground entrance. - Great Smoky Mountains National Park Roads & Bridges, Deep Creek Road, Between Park Boundary near Bryson City & Deep Creek Campground, Gatlinburg, Sevier County, TN

  13. 4. Southwest elevation. View of entrance in recessed area showing ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. Southwest elevation. View of entrance in recessed area showing Colonial Revival detail. - Union Township School, East side of State Route 4033, North of State Route 4037, Ringtown, Schuylkill County, PA

  14. Halfthrough girder over entrance to scrap yard at western end ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Half-through girder over entrance to scrap yard at western end of trestle, looking NW. - Pennsylvania Railroad, French Creek Trestle, Spanning French Creek, north of Paradise Street, Phoenixville, Chester County, PA

  15. 42. VIEW OF THE DUDLEY STREET ENTRANCE, SPRUCE POLE FENCE, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    42. VIEW OF THE DUDLEY STREET ENTRANCE, SPRUCE POLE FENCE, AND HISTORIC PARKING AREA WITH STORAGE SHED IN CENTER BACKGROUND. (NOTE: NEW CONCRETE SIDEWALK ALONG DUDLEY STREET IN RIGHT FOREGROUND). - Fairsted, 99 Warren Street, Brookline, Norfolk County, MA

  16. VIEW OF BUILDING 10, SOUTH SIDE, ENTRANCE, ON RICHARDSON AVENUE, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    VIEW OF BUILDING 10, SOUTH SIDE, ENTRANCE, ON RICHARDSON AVENUE, FACING NORTH - Roosevelt Base, Fleet Landing Building, Bounded by Richardson & Pratt Avenues, Maryland & West Virginia Streets, Long Beach, Los Angeles County, CA

  17. 42. VIEW OF WALL AT EAST ENTRANCE TO WALKWAY. 'FRANK ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    42. VIEW OF WALL AT EAST ENTRANCE TO WALKWAY. 'FRANK AUZA, FLAGSTAFF SHEEP CO.' SCRATCHED INTO FRESH MORTAR CAP ON STONE WALL. February 1987 - Verde River Sheep Bridge, Spanning Verde River (Tonto National Forest), Cave Creek, Maricopa County, AZ

  18. 31. VIEW OF CONCRETE SLAB AT WEST ENTRANCE OF WALKWAY. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    31. VIEW OF CONCRETE SLAB AT WEST ENTRANCE OF WALKWAY. '1944 JOE LANDETA' SCRATCHED INTO FRESH CONCRETE. March 1987 - Verde River Sheep Bridge, Spanning Verde River (Tonto National Forest), Cave Creek, Maricopa County, AZ

  19. DETAIL OF MAIN ENTRANCE ON EAST (FRONT) ELEVATION OF BUILDING. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    DETAIL OF MAIN ENTRANCE ON EAST (FRONT) ELEVATION OF BUILDING. view TO SOUTHWEST. - Plattsburgh Air Force Base, Target Intelligence Training Building-Combat Center, Off Connecticut Road, east of Idaho Avenue, Plattsburgh, Clinton County, NY

  20. 26. VIEW SHOWING ENTRANCE TO SILO 'ALFA,' LOOKING NORTH Marilyn ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    26. VIEW SHOWING ENTRANCE TO SILO 'ALFA,' LOOKING NORTH Marilyn Ziemer and Everett Weinreb, photographers, March 1988 - Mount Gleason Nike Missile Site, Angeles National Forest, South of Soledad Canyon, Sylmar, Los Angeles County, CA

  1. 25. VIEW SHOWING ENTRANCE TO SILO 'ALFA,' LOOKING WEST Everett ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    25. VIEW SHOWING ENTRANCE TO SILO 'ALFA,' LOOKING WEST Everett Weinreb, photographer, March 1988 - Mount Gleason Nike Missile Site, Angeles National Forest, South of Soledad Canyon, Sylmar, Los Angeles County, CA

  2. 2. VIEW OF BARRACKS AREA, SHOWING ENTRANCE GATE AT IMMEDIATE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. VIEW OF BARRACKS AREA, SHOWING ENTRANCE GATE AT IMMEDIATE LEFT, LOOKING WEST Everett Weinreb, photographer, March 1988 - Mount Gleason Nike Missile Site, Angeles National Forest, South of Soledad Canyon, Sylmar, Los Angeles County, CA

  3. 13. View of west entrance to central corridor of filtration ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    13. View of west entrance to central corridor of filtration bed building. - Lake Whitney Water Filtration Plant, Filtration Plant, South side of Armory Street between Edgehill Road & Whitney Avenue, Hamden, New Haven County, CT

  4. 5. Lighthouse, first floor and stairs, looking south from entrance ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    5. Lighthouse, first floor and stairs, looking south from entrance - Squirrel Point Light Station, Off Highway 127, Steen Road to end of Bald Head Road, .8 mile down footpath, Arrowsic, Sagadahoc County, ME

  5. 13. DETAIL SHOWING RETAINING WALL STEPS AND ENTRANCE TO FOUNTAIN, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    13. DETAIL SHOWING RETAINING WALL STEPS AND ENTRANCE TO FOUNTAIN, SOUTHEAST CORNER OF HALE BATHHOUSE IS VISIBLE IN BACKGROUND - Bathhouse Row, Hale Bathhouse, Central Avenue, Hot Springs, Garland County, AR

  6. View of south entrance to #157 through south breezeway arches ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    View of south entrance to #157 through south breezeway arches - National Home for Disabled Volunteer Soldiers, Pacific Branch, Mental Health Buildings, 11301 Wilshire Boulevard, West Los Angeles, Los Angeles County, CA

  7. Historic interior view of the entrance taken shortly after battle, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Historic interior view of the entrance taken shortly after battle, looking toward the southwest showing damage to gorge as well as timber and earth blindage. - Fort Pulaski, Cockspur Island, Savannah, Chatham County, GA

  8. Detail of stairway and main entrance on west front of ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Detail of stairway and main entrance on west front of center block, showing steps and frame canopy. View to southeast. - Southern Ute Boarding School, Boy's Dormitory, Ouray & Capote Drives, Ignacio, La Plata County, CO

  9. 39. DINING ROOM, LOOKING (NORTH) BACK TOWARD ENTRANCE. BEFORE 1907, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    39. DINING ROOM, LOOKING (NORTH) BACK TOWARD ENTRANCE. BEFORE 1907, GUESTS AT THE INN ATE FAMILY-STYLE AT LONG RECTANGULAR TABLES. - Old Faithful Inn, 900' northeast of Snowlodge & 1050' west of Old Faithful Lodge, Lake, Teton County, WY

  10. MAIN ENTRANCE GATE ON CAMP BUTLER ROAD, LOOKING INTO CEMETERY. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    MAIN ENTRANCE GATE ON CAMP BUTLER ROAD, LOOKING INTO CEMETERY. GATEPOST WRAPPED DURING CONSTRUCTION. VIEW TO NORTH. - Camp Butler National Cemetery, 5063 Camp Butler Road, Springfield, Sangamon County, IL

  11. 6. DETAIL, WEST SIDE, SOUTH BAY, SHOWING ENTRANCE TO INSTRUMENTATION ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    6. DETAIL, WEST SIDE, SOUTH BAY, SHOWING ENTRANCE TO INSTRUMENTATION ROOM. - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Test Stand 1-4, Test Area 1-115, northwest end of Saturn Boulevard, Boron, Kern County, CA

  12. 2. POST ENGINEER'S SHOPS AND YARD BUILDINGS FROM PRESIDIO ENTRANCE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. POST ENGINEER'S SHOPS AND YARD BUILDINGS FROM PRESIDIO ENTRANCE GATE AT MASON STREET, LOOKING 270 DEGREES WEST - Presidio of San Francisco, Post Engineer's Headquarters Office, Crissy Field North cantonment, San Francisco, San Francisco County, CA

  13. 1. General view of guard house and entrance to Coast ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. General view of guard house and entrance to Coast Guard Base from La Putilla Street, looking southwest - U.S. Coast Guard Base, San Juan, Guard House, La Puntilla Finalle, San Juan, San Juan Municipio, PR

  14. 10. DETAIL INTERIOR VIEW SHOWING MAIN ENTRANCE DOORS TO AUDITORIUM ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    10. DETAIL INTERIOR VIEW SHOWING MAIN ENTRANCE DOORS TO AUDITORIUM BUILDING; STAIRS IN FOREGROUND LEAD TO BASKETBALL COURT/STAGE AREA. - Bonneville Project, Auditorium, Columbia River, 1 mile Northeast of Exit 40, Interstate 84, Bonneville, Multnomah County, OR

  15. 21. FOLDING DOORS AT RAIL SPUR ENTRANCE TO NORTH END ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    21. FOLDING DOORS AT RAIL SPUR ENTRANCE TO NORTH END OF PLANT. VIEW TO EAST. - Ford Motor Company Long Beach Assembly Plant, Assembly Building, 700 Henry Ford Avenue, Long Beach, Los Angeles County, CA

  16. INTERIOR VIEW SHOWING MAIN ENTRANCE DOOR INTO SITTING ROOM AND ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    INTERIOR VIEW SHOWING MAIN ENTRANCE DOOR INTO SITTING ROOM AND DOOR TO PASSAGEWAY AND FERRY BUILDING IN DISTANCE - Ellis Island, New Immigration Building, New York Harbor, New York, New York County, NY

  17. 3. VIEW EAST, INTERIOR OF UNNUMBERED SCREEN HEADHOUSE, WITH ENTRANCES ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    3. VIEW EAST, INTERIOR OF UNNUMBERED SCREEN HEADHOUSE, WITH ENTRANCES TO GREENHOUSES #3, #4, #5 (BUILDINGS 7, 8, 9) - U.S. Plant Introduction Station, Greenhouse Nos. 3-8, 11601 Old Pond Road, Glenn Dale, Prince George's County, MD

  18. Main branch looking west from lake. Chicago River entrance locks, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Main branch looking west from lake. Chicago River entrance locks, Outer Drive Bridgge in foreground. - Chicago River Bascule Bridges, Spanning Chicago River & its north & south branches, Chicago, Cook County, IL

  19. 5. April 1963 DETAIL OF STEPS AND ENTRANCE, SOUTH FRONT ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    5. April 1963 DETAIL OF STEPS AND ENTRANCE, SOUTH FRONT - Shaker East Family Sisters' Shop, North side of Village Road, North of U.S. Route 68 & State Route 33 intersection, Shakertown, Mercer County, KY

  20. Historical bathymetric changes near the entrance to Grays Harbor, Washington

    SciTech Connect

    Burch, T.L.; Sherwood, C.R. )

    1992-12-01

    Large changes in the distribution of sediment near the entrance to Grays Harbor, Washington, have occurred since the long rock jetties were built to confine flow. Spits to the north and south of the entrance have grown, the entrance channel has deepened, and the outer bar has eroded and moved offshore. The shorelines of North Beach and South Beach have experienced significant amounts of both erosion and accretion since the jetties were constructed around the turn of the century. Recently, the erosion rate at South Beach has increased and, because Half Moon Bay is growing at the expense of the shoreward side of Point Chehalis, the vegetated portion of the spit is now less than 350 ft wide at the narrowest section. The US Army Corps of Engineers, Seattle District, requested that Battelle/Marine Sciences Laboratory evaluate long-term trends in erosion near the entrance to Grays Harbor.

  1. FEATURE 4, ARMCO HUT, ENTRANCE FACADE, VIEW FACING EASTSOUTHEAST (with ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    FEATURE 4, ARMCO HUT, ENTRANCE FACADE, VIEW FACING EAST-SOUTHEAST (with scale stick). - Naval Air Station Barbers Point, Anti-Aircraft Battery Complex-ARMCO Hut, East of Coral Sea Road, northwest of Hamilton Road, Ewa, Honolulu County, HI

  2. FEATURE 4, ARMCO HUT, ENTRANCE FACADE, VIEW FACING EASTSOUTHEAST. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    FEATURE 4, ARMCO HUT, ENTRANCE FACADE, VIEW FACING EAST-SOUTHEAST. - Naval Air Station Barbers Point, Anti-Aircraft Battery Complex-ARMCO Hut, East of Coral Sea Road, northwest of Hamilton Road, Ewa, Honolulu County, HI

  3. 1. EXTERIOR VIEW, LOOKING EAST, WITH ENTRANCES AND SIDE ELEVATIONS ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. EXTERIOR VIEW, LOOKING EAST, WITH ENTRANCES AND SIDE ELEVATIONS ALONG THE OLD BANKHEAD HIGHWAY (NOW 20TH STREET) AND ELLIOTT BOULEVARD - G. W. Posey Store, Twentieth Street & Elliot Boulevard, Jasper, Walker County, AL

  4. Kinetics of human immunodeficiency virus budding and assembly

    NASA Astrophysics Data System (ADS)

    Zhang, Rui; Nguyen, Toan

    2009-03-01

    Human immunodeficiency virus (HIV) belongs to a large family of RNA viruses, retroviruses. Unlike budding of regular enveloped viruses, retroviruses bud concurrently with the assembly of retroviral capsids on the cell membrane. The kinetics of HIV (and other retroviruses) budding and assembly is therefore strongly affected by the elastic energy of the membrane and fundamentally different from regular viruses. The main result of this work shows that the kinetics is tunable from a fast budding process to a slow and effectively trapped partial budding process, by varying the attractive energy of retroviral proteins (call Gags), relative to the membrane elastic energy. When the Gag-Gag attraction is relatively high, the membrane elastic energy provides a kinetic barrier for the two pieces of the partial capsids to merge. This energy barrier determines the slowest step in the kinetics and the budding time. In the opposite limit, the membrane elastic energy provides not only a kinetic energy barrier, but a free energy barrier. The budding and assembly is effectively trapped at local free energy minimum, corresponding to a partially budded state. The time scale to escape from this metastable state is exponentially large. In both cases, our result fit with experimental measurements pretty well.

  5. An elastic model of partial budding of retroviruses

    NASA Astrophysics Data System (ADS)

    Zhang, Rui; Nguyen, Toan

    2008-03-01

    Retroviruses are characterized by their unique infection strategy of reverse transcription, in which the genetic information flows from RNA back to DNA. The most well known representative is the human immunodeficiency virus (HIV). Unlike budding of traditional enveloped viruses, retrovirus budding happens together with the formation of spherical virus capsids at the cell membrane. Led by this unique budding mechanism, we proposed an elastic model of retrovirus budding in this work. We found that if the lipid molecules of the membrane are supplied fast enough from the cell interior, the budding always proceeds to completion. In the opposite limit, there is an optimal size of partially budded virions. The zenith angle of these partially spherical capsids, α, is given by α˜(2̂/κσ)^1/4, where κ is the bending modulus of the membrane, σ is the surface tension of the membrane, and τ characterizes the strength of capsid protein interaction. If τ is large enough such that α˜π, the budding is complete. Our model explained many features of retrovirus partial budding observed in experiments.

  6. Desiccation tolerance of dormant buds from selected Prunus species

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Dormant buds of woody plant species present a convenient material for backing-up of germplasm in liquid nitrogen. Routinely, this type of material is used in long-term preservation of only a few species (e.g. apple and sour cherry). Cryopreservation procedures of dormant buds are species dependent, ...

  7. Season of fire manipulates bud bank dynamics in northern mixed-grass prairie

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In perennial grassland dominated systems, belowground bud banks regulate plant community dynamics. Plant community responses to disturbance are largely driven by the ability to generate future aboveground growth originating from belowground axillary buds. This study examined bud bank dynamics for...

  8. Elevation and plan of east side entrance. San Bernardino Valley ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Elevation and plan of east side entrance. San Bernardino Valley Union Junior College, Library Building. Also includes sections II and SS of entrance hall; and a stress diagram of steel truss. Howard E. Jones, Architect, San Bernardino, California. Sheet 7, job no. 315. Scale 1/2 inch to the foot. No date given on sheet (probably March or April, 1927). - San Bernardino Valley College, Library, 701 South Mount Vernon Avenue, San Bernardino, San Bernardino County, CA

  9. Imaging Spectrometer Designs Utilizing Immersed Gratings With Accessible Entrance Slit

    DOEpatents

    Chrisp, Michael P.; Lerner, Scott A.

    2006-03-21

    A compact imaging spectrometer comprises an entrance slit, a catadioptric lens with a mirrored surface, a grating, and a detector array. The entrance slit directs light to the mirrored surface of the catadioptric lens; the mirrored surface reflects the light back through the lens to the grating. The grating receives the light from the catadioptric lens and diffracts the light to the lens away from the mirrored surface. The lens transmits the light and focuses it onto the detector array.

  10. Changing climate cues differentially alter zooplankton dormancy dynamics across latitudes.

    PubMed

    Jones, Natalie T; Gilbert, Benjamin

    2016-03-01

    In seasonal climates, dormancy is a common strategy that structures biodiversity and is necessary for the persistence of many species. Climate change will likely alter dormancy dynamics in zooplankton, the basis of aquatic food webs, by altering two important hatching cues: mean temperatures during the ice-free season, and mean day length when lakes become ice free. Theory suggests that these changes could alter diversity, hatchling abundances and phenology within lakes, and that these responses may diverge across latitudes due to differences in optimal hatching cues and strategies. To examine the role of temperature and day length on hatching dynamics, we collected sediment from 25 lakes across a 1800 km latitudinal gradient and exposed sediment samples to a factorial combination of two photoperiods (12 and 16 h) and two temperatures (8 and 12 °C) representative of historical southern (short photoperiod, warm) and northern (long photoperiod, cool) lake conditions. We tested whether sensitivity to these hatching cues varies by latitudinal origin and differs among taxa. Higher temperatures advanced phenology for all taxa, and these advances were greatest for cladocerans followed by copepods and rotifers. Although phenology differed among taxa, the effect of temperature did not vary with latitude. The latitudinal origin of the egg bank influenced egg abundance and hatchling abundance and diversity, with these latter effects varying with taxa, temperature and photoperiod. Copepod hatchling abundances peaked at mid-latitudes in the high temperature and long photoperiod treatments, whereas hatchling abundances of other zooplankton were greatest at low latitudes and high temperature. The overall diversity of crustacean zooplankton (copepods and cladocerans) also reflected distinct responses of each taxa to our treatments, with the greatest diversity occurring at mid-latitudes (~56 °N) in the shorter photoperiod treatment. Our results demonstrate that hatching cues differ for broad taxonomic groups that vary in developmental and life-history strategies. These differences are predicted to drive latitude-specific shifts in zooplankton emergence with climate change and could alter the base of aquatic food webs. PMID:26590065

  11. SMAD signaling and redox imbalance cooperate to induce prostate cancer cell dormancy.

    PubMed

    Bui, Anh Thu; Laurent, Fanny; Havard, Maryline; Dautry, François; Tchénio, Thierry

    2015-01-01

    Metastasis involves the dissemination of single or small clumps of cancer cells through blood or lymphatic vessels and their extravasation into distant organs. Despite the strong regulation of metastases development by a cell dormancy phenomenon, the dormant state of cancer cells remains poorly characterized due to the difficulty of in vivo studies. We have recently shown in vitro that clonogenicity of prostate cancer cells is regulated by a dormancy phenomenon that is strongly induced when cells are cultured both at low cell density and in a slightly hypertonic medium. Here, we characterized by RT-qPCR a genetic expression signature of this dormant state which combines the presence of both stemness and differentiation markers. We showed that both TFGβ/BMP signaling and redox imbalance are required for the full induction of this dormancy signature and cell quiescence. Moreover, reconstruction experiments showed that TFGβ/BMP signaling and redox imbalance are sufficient to generate a pattern of genetic expression displaying all characteristic features of the dormancy signature. Finally, we observed that low cell density was sufficient to activate TGFβ/BMP signaling and to generate a slight redox imbalance thus priming cells for dormancy that can be attained with a co-stimulus like hypertonicity, most likely through an increased redox imbalance. The identification of a dual regulation of dormancy provides a framework for the interpretation of previous reports showing a restricted ability of BMP signaling to regulate cancer cell dormancy in vivo and draws attention on the role of oxidative stress in the metastatic process. PMID:25706341

  12. Fluctuation of Arabidopsis seed dormancy with relative humidity and temperature during dry storage

    PubMed Central

    Basbouss-Serhal, Isabelle; Leymarie, Juliette; Bailly, Christophe

    2016-01-01

    The changes in germination potential of freshly harvested seeds of Arabidopsis thaliana stored in various combinations of temperature and relative humidity were investigated over 63 weeks of storage. Seeds of the wild type Col-0 and of two mutants displaying low and high levels of dormancy, cat2-1 and mtr4-1, respectively, were stored at harvest in 24 different environments including a combination of eight relative humidities, from 1 to 85%, and four temperatures (10, 15, 20, and 25 °C). These mutations did not influence behaviour of seeds during storage. Primary dormant seeds did not germinate in darkness at 25 °C but acquired the potential to germinate at this temperature within 7 weeks when stored in relative humidities close to 50% across all temperatures. Sorption isotherms and Arrhenius plots demonstrated that the seed moisture content of 0.06g H2O/g dry weight was a critical value below which dormancy release was associated with reactions of negative activation energy and above which dormancy release increased with temperature. Longer storage times when relative humidity did not exceed 75–85% led to decreased germination at 25 °C, corresponding to the induction of secondary dormancy. Dormancy release and induction of secondary dormancy in the dry state were associated with induction or repression of key genes related to abscisic acid and gibberellins biosynthesis and signalling pathways. In high relative humidity, prolonged storage of seeds induced ageing and progressive loss of viability, but this was not related to the initial level of dormancy. PMID:26428064

  13. Seed dormancy and germination in Jeffersonia dubia (Berberidaceae) as affected by temperature and gibberellic acid.

    PubMed

    Rhie, Y H; Lee, S Y; Kim, K S

    2015-03-01

    The genus Jeffersonia, which contains only two species, has a trans-Atlantic disjunct distribution. The aims of this study were to determine the requirements for breaking dormancy and germination of J. dubia seeds and to compare its dormancy characteristics with those of the congener in eastern North America. Ripe seeds of J. dubia contain an underdeveloped embryo and were permeable to water. In nature, seeds were dispersed in May, while embryos began to grow in September, and were fully elongated by late November. Germination started in March of the next year, and seeds emerged as seedlings soon after germination. In laboratory experiments, incubation at high temperatures (25 °C, 25/15 °C) for at least 8 weeks was required to initiate embryo growth, while a transfer to moderate temperatures (20/10 °C, 15/6 °C) was needed for the completion of embryo growth. At least 8 weeks at 5 °C was effective in overcoming physiological dormancy and for germination in seeds after the embryos had fully elongated. Thus, both high and low temperatures were essential to break dormancy. Gibberellic acid (GA3 ) treatment could substitute for the high temperature requirement, but not for the low temperature requirement. Based on the dormancy-breaking requirements, it is confirmed that the seeds have deep simple morphophysiological dormancy. This dormancy type is similar to that of seeds of the eastern North American species J. diphylla. Although seeds require 10-11 months from seed dispersal to germination in nature, under controlled conditions they required only 3 months after treatment with 1000 mg·l(-1) GA3 , followed by incubation at 15/6 °C. This represents practical knowledge for propagation of these plants from seed. PMID:25319374

  14. Temperature rather than photoperiod controls growth cessation and dormancy in Sorbus species

    PubMed Central

    Heide, Ola M.

    2011-01-01

    Environmental regulation of growth and dormancy of four Sorbus genotypes was studied in controlled environments. Emphasis was placed on assessment of the presence and nature of the deficient photoperiodic dormancy regulation system that has previously been reported for some woody Rosaceae species. Two genotypes of Sorbus aucuparia L. maintained indeterminate growth for 8 weeks and 9 weeks at temperatures of 15 °C and 21 °C in both 20 h and 10 h photoperiods, while at 9 °C, in the same photoperiodic conditions, they immediately ceased growing. At the higher temperatures, initiation of new leaves (nodes) was unaffected by photoperiod, while internode elongation was significantly enhanced by long days (LD). However, even after prolonged exposure to 9 °C, most plants resumed growth when moved to high temperature and LD, indicating a shallow state of dormancy. Seedlings of Sorbus intermedia (J. F. Ehrh.) Pers. and micro-propagated plantlets of S. commixta Hedl. ‘Dodong’ were also unaffected by photoperiod during primary growth, but failed to elongate and gradually became dormant regardless of temperature and day-length conditions. However, after chilling and breaking of dormancy, the plants elongated vigorously but changed to a determinate mode of growth. Furthermore, a temperature of 9 °C was found to be fully effective for breaking dormancy in S. intermedia plants. It is concluded that deficient photoperiodic dormancy control seems widespread in the Rosaceae and that, in such plants, both dormancy induction and release is brought about by low temperature. The potential impacts of climate change on such trees are discussed. PMID:21862485

  15. SMAD signaling and redox imbalance cooperate to induce prostate cancer cell dormancy

    PubMed Central

    Bui, Anh Thu; Laurent, Fanny; Havard, Maryline; Dautry, François; Tchénio, Thierry

    2015-01-01

    Metastasis involves the dissemination of single or small clumps of cancer cells through blood or lymphatic vessels and their extravasation into distant organs. Despite the strong regulation of metastases development by a cell dormancy phenomenon, the dormant state of cancer cells remains poorly characterized due to the difficulty of in vivo studies. We have recently shown in vitro that clonogenicity of prostate cancer cells is regulated by a dormancy phenomenon that is strongly induced when cells are cultured both at low cell density and in a slightly hypertonic medium. Here, we characterized by RT-qPCR a genetic expression signature of this dormant state which combines the presence of both stemness and differentiation markers. We showed that both TFGβ/BMP signaling and redox imbalance are required for the full induction of this dormancy signature and cell quiescence. Moreover, reconstruction experiments showed that TFGβ/BMP signaling and redox imbalance are sufficient to generate a pattern of genetic expression displaying all characteristic features of the dormancy signature. Finally, we observed that low cell density was sufficient to activate TGFβ/BMP signaling and to generate a slight redox imbalance thus priming cells for dormancy that can be attained with a co-stimulus like hypertonicity, most likely through an increased redox imbalance. The identification of a dual regulation of dormancy provides a framework for the interpretation of previous reports showing a restricted ability of BMP signaling to regulate cancer cell dormancy in vivo and draws attention on the role of oxidative stress in the metastatic process. PMID:25706341

  16. Budding Yeast for Budding Geneticists: A Primer on the Saccharomyces cerevisiae Model System

    PubMed Central

    Duina, Andrea A.; Miller, Mary E.; Keeney, Jill B.

    2014-01-01

    The budding yeast Saccharomyces cerevisiae is a powerful model organism for studying fundamental aspects of eukaryotic cell biology. This Primer article presents a brief historical perspective on the emergence of this organism as a premier experimental system over the course of the past century. An overview of the central features of the S. cerevisiae genome, including the nature of its genetic elements and general organization, is also provided. Some of the most common experimental tools and resources available to yeast geneticists are presented in a way designed to engage and challenge undergraduate and graduate students eager to learn more about the experimental amenability of budding yeast. Finally, a discussion of several major discoveries derived from yeast studies highlights the far-reaching impact that the yeast system has had and will continue to have on our understanding of a variety of cellular processes relevant to all eukaryotes, including humans. PMID:24807111

  17. Elucidation of novel budding yeast separase mutants.

    PubMed

    Shimizu, Yoshihito; Nagai, Masayoshi; Yeasmin, Akter Mst; Koike, Naoki; Talukdar, Muhammad Waliullah; Ushimaru, Takashi

    2016-03-01

    The mitotic separase cleaves Scc1 in cohesin to allow sister chromatids to separate from each other upon anaphase onset. Separase is also required for DNA damage repair. Here, we isolated and characterized 10 temperature-sensitive (ts) mutants of separase ESP1 in the budding yeast Saccharomyces cerevisiae. All mutants were defective in sister chromatid separation at the restricted temperature. Some esp1-ts mutants were hypersensitive to the microtubule poison benomyl and/or the DNA-damaging agent bleomycin. Overexpression of securin alleviated the growth defect in some esp1-ts mutants, whereas it rather exacerbated it in others. The Drosophila Pumilio homolog MPT5 was isolated as a high-dosage suppressor of esp1-ts cells. We discuss various features of separase based on these findings. PMID:26523765

  18. Lipid droplet dynamics in budding yeast.

    PubMed

    Wang, Chao-Wen

    2015-07-01

    Eukaryotic cells store excess fatty acids as neutral lipids, predominantly triacylglycerols and sterol esters, in organelles termed lipid droplets (LDs) that bulge out from the endoplasmic reticulum. LDs are highly dynamic and contribute to diverse cellular functions. The catabolism of the storage lipids within LDs is channeled to multiple metabolic pathways, providing molecules for energy production, membrane building blocks, and lipid signaling. LDs have been implicated in a number of protein degradation and pathogen infection processes. LDs may be linked to prevalent human metabolic diseases and have marked potential for biofuel production. The knowledge accumulated on LDs in recent years provides a foundation for diverse, and even unexpected, future research. This review focuses on recent advances in LD research, emphasizing the diverse physiological roles of LDs in the model system of budding yeast. PMID:25894691

  19. A statistical-thermodynamic model of viral budding.

    PubMed

    Tzlil, Shelly; Deserno, Markus; Gelbart, William M; Ben-Shaul, Avinoam

    2004-04-01

    We present a simple statistical thermodynamic model for budding of viral nucleocapsids at the cell membrane. The membrane is modeled as a flexible lipid bilayer embedding linker (spike) proteins, which serve to anchor and thus wrap the membrane around the viral capsids. The free energy of a single bud is expressed as a sum of the bending energy of its membrane coat, the spike-mediated capsid-membrane adhesion energy, and the line energy associated with the bud's rim, all depending on the extent of wrapping (i.e., bud size), and density of spikes in the curved membrane. This self-energy is incorporated into a simple free energy functional for the many-bud system, allowing for different spike densities, and hence entropy, in the curved (budding) and planar membrane regions, as well as for the configurational entropy of the polydisperse bud population. The equilibrium spike densities in the coexisting, curved and planar, membrane regions are calculated as a function of the membrane bending energy and the spike-mediated adhesion energy, for different spike and nucleocapsid concentrations in the membrane plane, as well as for several values of the bud's rim energy. We show that complete budding (full wrapping of nucleocapsids) can only take place if the adhesion energy exceeds a certain, critical, bending free energy. Whenever budding takes place, the spike density in the mature virions is saturated, i.e., all spike adhesion sites are occupied. The rim energy plays an important role in determining the size distribution of buds. The fraction of fully wrapped buds increases as this energy increases, resulting eventually in an all-or-nothing mechanism, whereby nucleocapsids at the plasma membrane are either fully enveloped or completely naked (just touching the membrane). We also find that at low concentrations all capsids arriving at the membrane get tightly and fully enveloped. Beyond a certain concentration, corresponding approximately to a stoichiometric spike/capsid ratio, newly arriving capsids cannot be fully wrapped; i.e., the budding yield decreases. PMID:15041646

  20. Enhanced vadose zone nitrogen removal by poplar during dormancy.

    PubMed

    Ausland, Hayden; Ward, Adam; Licht, Louis; Just, Craig

    2015-01-01

    A pilot-scale, engineered poplar tree vadose zone system was utilized to determine effluent nitrate (NO3(-)) and ammonium concentrations resulting from intermittent dosing of a synthetic wastewater onto sandy soils at 4.5°C. The synthetic wastewater replicated that of an industrial food processor that irrigates onto sandy soils even during dormancy which can leave groundwater vulnerable to NO3(-) contamination. Data from a 21-day experiment was used to assess various Hydrus model parameterizations that simulated the impact of dormant roots. Bromide tracer data indicated that roots impacted the hydraulic properties of the packed sand by increasing effective dispersion, water content and residence time. The simulated effluent NO3(-) concentration on day 21 was 1.2 mg-N L(-1) in the rooted treatments compared to a measured value of 1.0 ± 0.72 mg-N L(-1). For the non-rooted treatment, the simulated NO3(-) concentration was 4.7 mg-N L(-1) compared to 5.1 ± 3.5 mg-N L(-1) measured on day 21. The model predicted a substantial "root benefit" toward protecting groundwater through increased denitrification in rooted treatments during a 21-day simulation with 8% of dosed nitrogen converted to N2 compared to 3.3% converted in the non-rooted test cells. Simulations at the 90-day timescale provided similar results, indicating increased denitrification in rooted treatments. PMID:26030360

  1. Epoxyeicosanoids stimulate multiorgan metastasis and tumor dormancy escape in mice

    PubMed Central

    Panigrahy, Dipak; Edin, Matthew L.; Lee, Craig R.; Huang, Sui; Bielenberg, Diane R.; Butterfield, Catherine E.; Barnés, Carmen M.; Mammoto, Akiko; Mammoto, Tadanori; Luria, Ayala; Benny, Ofra; Chaponis, Deviney M.; Dudley, Andrew C.; Greene, Emily R.; Vergilio, Jo-Anne; Pietramaggiori, Giorgio; Scherer-Pietramaggiori, Sandra S.; Short, Sarah M.; Seth, Meetu; Lih, Fred B.; Tomer, Kenneth B.; Yang, Jun; Schwendener, Reto A.; Hammock, Bruce D.; Falck, John R.; Manthati, Vijaya L.; Ingber, Donald E.; Kaipainen, Arja; D’Amore, Patricia A.; Kieran, Mark W.; Zeldin, Darryl C.

    2011-01-01

    Epoxyeicosatrienoic acids (EETs) are small molecules produced by cytochrome P450 epoxygenases. They are lipid mediators that act as autocrine or paracrine factors to regulate inflammation and vascular tone. As a result, drugs that raise EET levels are in clinical trials for the treatment of hypertension and many other diseases. However, despite their pleiotropic effects on cells, little is known about the role of these epoxyeicosanoids in cancer. Here, using genetic and pharmacological manipulation of endogenous EET levels, we demonstrate that EETs are critical for primary tumor growth and metastasis in a variety of mouse models of cancer. Remarkably, we found that EETs stimulated extensive multiorgan metastasis and escape from tumor dormancy in several tumor models. This systemic metastasis was not caused by excessive primary tumor growth but depended on endothelium-derived EETs at the site of metastasis. Administration of synthetic EETs recapitulated these results, while EET antagonists suppressed tumor growth and metastasis, demonstrating in vivo that pharmacological modulation of EETs can affect cancer growth. Furthermore, inhibitors of soluble epoxide hydrolase (sEH), the enzyme that metabolizes EETs, elevated endogenous EET levels and promoted primary tumor growth and metastasis. Thus, our data indicate a central role for EETs in tumorigenesis, offering a mechanistic link between lipid signaling and cancer and emphasizing the critical importance of considering possible effects of EET-modulating drugs on cancer. PMID:22182838

  2. Virus-Induced Dormancy in the Archaeon Sulfolobus islandicus

    PubMed Central

    Bautista, Maria A.; Zhang, Changyi

    2015-01-01

    ABSTRACT We investigated the interaction between Sulfolobus spindle-shaped virus (SSV9) and its native archaeal host Sulfolobus islandicus. We show that upon exposure to SSV9, S. islandicus strain RJW002 has a significant growth delay where the majority of cells are dormant (viable but not growing) for 24 to 48 hours postinfection (hpi) compared to the growth of controls without virus. We demonstrate that in this system, dormancy (i) is induced by both active and inactive virus particles at a low multiplicity of infection (MOI), (ii) is reversible in strains with active CRISPR-Cas immunity that prevents the establishment of productive infections, and (iii) results in dramatic and rapid host death if virus persists in the culture even at low levels. Our results add a new dimension to evolutionary models of virus-host interactions, showing that the mere presence of a virus induces host cell stasis and death independent of infection. This novel, highly sensitive, and risky bet-hedging antiviral response must be integrated into models of virus-host interactions in this system so that the true ecological impact of viruses can be predicted and understood. PMID:25827422

  3. Influence of the Testa on Seed Dormancy, Germination, and Longevity in Arabidopsis1

    PubMed Central

    Debeaujon, Isabelle; Léon-Kloosterziel, Karen M.; Koornneef, Maarten

    2000-01-01

    The testa of higher plant seeds protects the embryo against adverse environmental conditions. Its role is assumed mainly by controlling germination through dormancy imposition and by limiting the detrimental activity of physical and biological agents during seed storage. To analyze the function of the testa in the model plant Arabidopsis, we compared mutants affected in testa pigmentation and/or structure for dormancy, germination, and storability. The seeds of most mutants exhibited reduced dormancy. Moreover, unlike wild-type testas, mutant testas were permeable to tetrazolium salts. These altered dormancy and tetrazolium uptake properties were related to defects in the pigmentation of the endothelium and its neighboring crushed parenchymatic layers, as determined by vanillin staining and microscopic observations. Structural aberrations such as missing layers or a modified epidermal layer in specific mutants also affected dormancy levels and permeability to tetrazolium. Both structural and pigmentation mutants deteriorated faster than the wild types during natural aging at room temperature, with structural mutants being the most strongly affected. PMID:10677433

  4. The Arabidopsis MYB96 transcription factor plays a role in seed dormancy.

    PubMed

    Lee, Hong Gil; Lee, Kyounghee; Seo, Pil Joon

    2015-03-01

    Seed dormancy facilitates to endure environmental disadvantages by confining embryonic growth until the seeds encounter favorable environmental conditions for germination. Abscisic acid (ABA) and gibberellic acid (GA) play a pivotal role in the determination of the seed dormancy state. ABA establishes seed dormancy, while GA triggers seed germination. Here, we demonstrate that MYB96 contributes to the fine-tuning of seed dormancy regulation through the coordination of ABA and GA metabolism. The MYB96-deficient myb96-1 seeds germinated earlier than wild-type seeds, whereas delayed germination was observed in the activation-tagging myb96-1D seeds. The differences in germination rate disappeared after stratification or after-ripening. The MYB96 transcription factor positively regulates ABA biosynthesis genes 9-CIS-EPOXYCAROTENOID DIOXYGENASE 2 (NCED2), NCED5, NCED6, and NCED9, and also affects GA biosynthetic genes GA3ox1 and GA20ox1. Notably, MYB96 directly binds to the promoters of NCED2 and NCED6, primarily modulating ABA biosynthesis, which subsequently influences GA metabolism. In agreement with this, hyperdormancy of myb96-1D seeds was recovered by an ABA biosynthesis inhibitor fluridone, while hypodormancy of myb96-1 seeds was suppressed by a GA biosynthesis inhibitor paclobutrazol (PAC). Taken together, the metabolic balance of ABA and GA underlies MYB96 control of primary seed dormancy. PMID:25616734

  5. Are fungi important for breaking seed dormancy in desert species? Experimental evidence in Opuntia streptacantha (Cactaceae).

    PubMed

    Delgado-Sánchez, P; Ortega-Amaro, M A; Jiménez-Bremont, J F; Flores, J

    2011-01-01

    Seeds of Opuntia spp. have physiological dormancy; they need a period of after-ripening to break dormancy, and the embryos have low growth potential. We evaluated the combined effects of seed age and presence of fungi on the testa on germination of Opuntia streptacantha, an abundant species in the Chihuahuan Desert (Mexico), assuming that older seeds have broken seed dormancy and fungi can reduce mechanical resistance to germination. In a preliminary experiment, we found no germination of 9-year-old (1998) and freshly collected (2007) seeds. However, we obtained 67% and 27% germination from 9-year-old and fresh non-sterilized seeds, respectively, and found fungi growing on the testa of all germinated seeds. Two fungal strains were isolated and identified using ribosomal internal transcribed spacer (ITS) sequence analysis: Penicillium chrysogenum and Phoma sp. In a second experiment, we inoculated seeds with strains of P. chrysogenum and Phoma sp., as well as Trichoderma koningii and binucleate Rhizoctonia (Gto17S2), to evaluate their ability to break seed dormancy. Seeds inoculated with P. chrysogenum, Phoma sp. and T. koningii had higher germination than controls for both seed ages, but germination was higher in older seeds. Scanning electron microscopy showed that these fungi eroded the funiculus, reducing its resistance. Binucleate Rhizoctonia did not lead to germination and controls had almost no germination. Our results strongly indicate that fungi are involved in breaking seed dormancy of O. streptacantha, and that the effect of fungi on seeds is species-specific. PMID:21143736

  6. A proposed mechanism for physical dormancy break in seeds of Ipomoea lacunosa (Convolvulaceae)

    PubMed Central

    Jayasuriya, K. M. G. Gehan; Baskin, Jerry M.; Geneve, Robert L.; Baskin, Carol C.

    2009-01-01

    Background and Aims The water-impermeable seeds of Ipomoea lacunosa undergo sensitivity cycling to dormancy breaking treatment, and slits are formed around bulges adjacent to the micropyle during dormancy break, i.e. the water gap opens. The primary aim of this research was to identify the mechanism of slit formation in seeds of this species. Methods Sensitive seeds were incubated at various combinations of relative humidity (RH) and temperature after blocking the hilar area in different places. Increase in seed mass was measured before and after incubation. Scanning electron microscopy (SEM) and staining of insensitive and sensitive seeds were carried out to characterize these states morphologically and anatomically. Water absorption was monitored at 35 and 25 °C at 100 % RH. Key Results There was a significant relationship between incubation temperature and RH with percentage seed dormancy break. Sensitive seeds absorbed water vapour, but insensitive seeds did not. Different amounts of water were absorbed by seeds with different blocking treatments. There was a significant relationship between dormancy break and the amount of water absorbed during incubation. Conclusions Water vapour seals openings that allow it to escape from seeds and causes pressure to develop below the bulge, thereby causing slits to form. A model for the mechanism of formation of slits (physical dormancy break) is proposed. PMID:19098068

  7. [Effects of photoperiod on photosynthesis and PSII performance in peach during dormancy induction].

    PubMed

    Li, Dong-Mei; Tan, Qiu-Ping; Gao, Dong-Sheng; Chen, Xiu-De; Li, Ling

    2014-07-01

    Long-day and short-day photoperiods were set artificially, with natural condition as the control, to examine photosynthetic parameters and chlorophyll fluorescence transient kinetics of 6-year-old 'Chunjie' peach cultivar (Prunus persica cv. Chunjie), and to investigate the effects of photoperiod on photosynthesis of the northern deciduous fruit trees. The tree advanced into the dormancy induction period under the short-day condition, and delayed under the long-day condition. In the dormancy induction period, the leaf net photosynthetic rate (Pn) and stomatal conductance (g(s)) decreased, and the intercellular CO2 concentration (Ci) increased, suggesting that the Pn decreased because of non-stomatal limitation. Maximum quantum yield for primary photochemistry (PhiPo, or Fv/Fm), potential activity (Fv/Fo), probability that a trapped exciton moved an electron into the electron transport chain beyond Q(A)-(Psi(o)) and performance index on absorption basis (Pl(ABS)) decreased in the dormancy induction period, suggesting that the electron transport capacity of photosynthetic electron transport chain was inhibited, possibly due to the damage to downstream electron transport chain (after Q(A)- acceptor) of PS II reaction center. Long-day photoperiod improved Pn in the dormancy induction period, and reduced the range of decline in PI(ABS) and the injured degree of photosystem. Short-day photoperiod deepened and accelerated the damage to photosynthetic apparatus significantly. The induced effect of photoperiod was associated with the dormancy processes. PMID:25345042

  8. Molecular and Pathogenetic Aspects of Tumor Budding in Colorectal Cancer

    PubMed Central

    Dawson, Heather; Lugli, Alessandro

    2015-01-01

    In recent years, tumor budding in colorectal cancer has gained much attention as an indicator of lymph node metastasis, distant metastatic disease, local recurrence, worse overall and disease-free survival, and as an independent prognostic factor. Tumor buds, defined as the presence of single tumor cells or small clusters of up to five tumor cells at the peritumoral invasive front (peritumoral buds) or within the main tumor body (intratumoral buds), are thought to represent the morphological correlate of cancer cells having undergone epithelial–mesenchymal transition (EMT), an important mechanism for the progression of epithelial cancers. In contrast to their undisputed prognostic power and potential to influence clinical management, our current understanding of the biological background of tumor buds is less established. Most studies examining tumor buds have attempted to recapitulate findings of mechanistic EMT studies using immunohistochemical markers. The aim of this review is to provide a comprehensive summary of studies examining protein expression profiles of tumor buds and to illustrate the molecular pathways and crosstalk involved in their formation and maintenance. PMID:25806371

  9. Taste Bud Homeostasis in Health, Disease, and Aging

    PubMed Central

    2014-01-01

    The mammalian taste bud is an onion-shaped epithelial structure with 50–100 tightly packed cells, including taste receptor cells, supporting cells, and basal cells. Taste receptor cells detect nutrients and toxins in the oral cavity and transmit the sensory information to gustatory nerve endings in the buds. Supporting cells may play a role in the clearance of excess neurotransmitters after their release from taste receptor cells. Basal cells are precursor cells that differentiate into mature taste cells. Similar to other epithelial cells, taste cells turn over continuously, with an average life span of about 8–12 days. To maintain structural homeostasis in taste buds, new cells are generated to replace dying cells. Several recent studies using genetic lineage tracing methods have identified populations of progenitor/stem cells for taste buds, although contributions of these progenitor/stem cell populations to taste bud homeostasis have yet to be fully determined. Some regulatory factors of taste cell differentiation and degeneration have been identified, but our understanding of these aspects of taste bud homoeostasis remains limited. Many patients with various diseases develop taste disorders, including taste loss and taste distortion. Decline in taste function also occurs during aging. Recent studies suggest that disruption or alteration of taste bud homeostasis may contribute to taste dysfunction associated with disease and aging. PMID:24287552

  10. Inflammation activates the interferon signaling pathways in taste bud cells.

    PubMed

    Wang, Hong; Zhou, Minliang; Brand, Joseph; Huang, Liquan

    2007-10-01

    Patients with viral and bacterial infections or other inflammatory illnesses often experience taste dysfunctions. The agents responsible for these taste disorders are thought to be related to infection-induced inflammation, but the mechanisms are not known. As a first step in characterizing the possible role of inflammation in taste disorders, we report here evidence for the presence of interferon (IFN)-mediated signaling pathways in taste bud cells. IFN receptors, particularly the IFN-gamma receptor IFNGR1, are coexpressed with the taste cell-type markers neuronal cell adhesion molecule and alpha-gustducin, suggesting that both the taste receptor cells and synapse-forming cells in the taste bud can be stimulated by IFN. Incubation of taste bud-containing lingual epithelia with recombinant IFN-alpha and IFN-gamma triggered the IFN-mediated signaling cascades, resulting in the phosphorylation of the downstream STAT1 (signal transducer and activator of transcription protein 1) transcription factor. Intraperitoneal injection of lipopolysaccharide or polyinosinic:polycytidylic acid into mice, mimicking bacterial and viral infections, respectively, altered gene expression patterns in taste bud cells. Furthermore, the systemic administration of either IFN-alpha or IFN-gamma significantly increased the number of taste bud cells undergoing programmed cell death. These findings suggest that bacterial and viral infection-induced IFNs can act directly on taste bud cells, affecting their cellular function in taste transduction, and that IFN-induced apoptosis in taste buds may cause abnormal cell turnover and skew the representation of different taste bud cell types, leading to the development of taste disorders. To our knowledge, this is the first study providing direct evidence that inflammation can affect taste buds through cytokine signaling pathways. PMID:17913904

  11. The qSD12 Underlying Gene Promotes Abscisic Acid Accumulation in Early Developing Seeds to Induce Primary Dormancy in Rice

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Seeds acquire primary dormancy during their development and the phytohormone abscisic acid (ABA) is considered to play a role in inducing the dormancy. qSD12 is a major seed dormancy QTL identified from weedy rice. This research was conducted to identify qSD12 candidate genes, isolate the candidat...

  12. Grain dormancy loss is associated with changes in ABA and GA sensitivity and hormone accumulation in bread wheat, Triticum aestivum (L.)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Knowledge about the hormonal control of seed dormancy and dormancy loss is essential in wheat, because low seed dormancy at maturity is associated with the problem of preharvest sprouting (PHS) when rain occurs before harvest. Low GA (gibberellin) hormone sensitivity and high ABA (abscisic acid) sen...

  13. Reduction of seed dormancy in Echinacea pallida (Nutt.) Nutt. by in-dark seed selection and breeding

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Strong seed dormancy has been an obstacle for field production of Echinacea species. Previous research on overcoming Echinacea seed dormancy has been extensive and focused on treatment methods, which involve time and expense, and are incompatible with organic production if synthetic chemicals are us...

  14. Increased ABA sensitivity results in higher seed dormancy in soft white spring wheat cultivar ‘Zak’

    Technology Transfer Automated Retrieval System (TEKTRAN)

    As a strategy to increase the seed dormancy of soft white wheat, mutants with increased sensitivity to the plant hormone abscisic acid (ABA) were identified in mutagenized grain of soft white spring wheat ‘Zak”. Lack of seed dormancy is correlated with increased susceptibility to preharvest sprouti...

  15. Studies in seed dormancy : VII. The abscisic acid content of the seeds and fruits of Corylus avellana L.

    PubMed

    Williams, P M; Ross, J D; Bradbeer, J W

    1973-12-01

    ABA has been identified by GLC-MS and routinely determined by GLC as one of several inhibitory substances in the testa and pericarp of hazel nuts. Its concentration in newly harvested nuts, which had not developed embryo dormancy, was 19.0 nmoles/g dry weight for the testa, 1.4 nmoles/g for the pericarp and 0.09 nmoles/g for the embryo. Dry storage of the nuts resulted in the development of embryo dormancy together with a slight loss of ABA. On imbibition of dormant nuts at 5° C and 20° C there was a 61% loss of ABA from the testa and pericarp in both cases. However the 5° C imbibition resulted in the breaking of seed dormancy while the 20° C imbibition had no effect on the dormancy. The ABA of the testa and pericarp seems to be concerned with the maintenance of seed dormancy prior to the onset of embryo dormancy. Subsequent to the onset of embryo dormancy, ABA seems to show little effect on either the maintenance or breaking of seed dormancy. PMID:24474459

  16. qSD7-1 is the first dormancy QTL cloned from weedy rice (Oryza sativa)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We developed weedy rice (SS-18-2) as a genetic system to investigate mechanisms regulating natural variation in seed dormancy. This included introduction of a set of quantitative trait loci (QTL) enhancing seed dormancy into the non-dormant genetic background of cultivated rice (EM93-1) to clone and...

  17. Positional Cloning of qSD7-1, a Dormancy Locus Associated with Red Pericarp Color in Weedy Rice

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Seed dormancy has been associated with red pericarp color in cereal crops for about a century. However, it remains unknown if the association arises from pleiotropy or linkage. We identified a dormancy locus (i.e., qSD7-1) in the genomic region containing the red pericarp color gene Rc in weedy rice...

  18. Characterization of Septin Ultrastructure in Budding Yeast Using Electron Tomography

    PubMed Central

    Bertin, Aurélie; Nogales, Eva

    2015-01-01

    Summary Septins are essential for the completion of cytokinesis. In budding yeast, Saccharomyces cerevisiae, septins are located at the bud neck during mitosis and are closely connected to the inner plasma membrane. In vitro, yeast septins have been shown to self-assemble into a variety of filamentous structures, including rods, paired filaments, bundles and rings [1–3]. Using electron tomography of freeze-substituted section and cryo-electron tomography of frozen sections, we determined the three dimensional organization of the septin cytoskeleton in dividing budding yeast with molecular resolution [4,5]. Here we describe the detailed procedures used for our characterization of the septin cellular ultrastructure. PMID:26519309

  19. Cell cycle regulation during development and dormancy in embryos of the annual killifish Austrofundulus limnaeus

    PubMed Central

    Podrabsky, Jason E.; Culpepper, Kristin M.

    2012-01-01

    Embryos of the annual killifish Austrofundulus limnaeus can enter into a state of metabolic dormancy, termed diapause, as a normal part of their development. In addition, these embryos can also survive for prolonged sojourns in the complete absence of oxygen. Dormant embryos support their metabolism using anaerobic metabolic pathways, regardless of oxygen availability. Dormancy in diapause is associated with high ATP and a positive cellular energy status, while anoxia causes a severe reduction in ATP content and large reductions in adenylate energy charge and ATP/ADP ratios. Most cells are arrested in the G1/G0 phase of the cell cycle during diapause and in response to oxygen deprivation. In this paper, we review what is known about the physiological and biochemical mechanisms that support metabolic dormancy in this species. We also highlight the great potential that this model holds for identifying novel therapies for human diseases such as heart attack, stroke and cancer. PMID:22531486

  20. Regulation of Arabidopsis thaliana seed dormancy and germination by 12-oxo-phytodienoic acid

    PubMed Central

    Dave, Anuja; Vaistij, Fabián E.; Gilday, Alison D.; Penfield, Steven D.; Graham, Ian A.

    2016-01-01

    We previously demonstrated that the oxylipin 12-oxo-phytodienoic acid (OPDA) acts along with abscisic acid to regulate seed germination in Arabidopsis thaliana, but the mechanistic details of this synergistic interaction remain to be elucidated. Here, we show that OPDA acts through the germination inhibition effects of abscisic acid, the abscisic acid-sensing ABI5 protein, and the gibberellin-sensing RGL2 DELLA protein. We further demonstrate that OPDA also acts through another dormancy-promoting factor, MOTHER-OF-FT-AND-TFL1 (MFT). Both abscisic acid and MFT positively feed back into the OPDA pathway by promoting its accumulation. These results confirm the central role of OPDA in regulating seed dormancy and germination in A. thaliana and underline the complexity of interactions between OPDA and other dormancy-promoting factors such as abscisic acid, RGL2, and MFT. PMID:26873978

  1. Regulation of Arabidopsis thaliana seed dormancy and germination by 12-oxo-phytodienoic acid.

    PubMed

    Dave, Anuja; Vaistij, Fabián E; Gilday, Alison D; Penfield, Steven D; Graham, Ian A

    2016-04-01

    We previously demonstrated that the oxylipin 12-oxo-phytodienoic acid (OPDA) acts along with abscisic acid to regulate seed germination inArabidopsis thaliana, but the mechanistic details of this synergistic interaction remain to be elucidated. Here, we show that OPDA acts through the germination inhibition effects of abscisic acid, the abscisic acid-sensing ABI5 protein, and the gibberellin-sensing RGL2 DELLA protein. We further demonstrate that OPDA also acts through another dormancy-promoting factor, MOTHER-OF-FT-AND-TFL1 (MFT). Both abscisic acid and MFT positively feed back into the OPDA pathway by promoting its accumulation. These results confirm the central role of OPDA in regulating seed dormancy and germination inA. thalianaand underline the complexity of interactions between OPDA and other dormancy-promoting factors such as abscisic acid, RGL2, and MFT. PMID:26873978

  2. The role of the testa during development and in establishment of dormancy of the legume seed

    PubMed Central

    Smýkal, Petr; Vernoud, Vanessa; Blair, Matthew W.; Soukup, Aleš; Thompson, Richard D.

    2014-01-01

    Timing of seed germination is one of the key steps in plant life cycles. It determines the beginning of plant growth in natural or agricultural ecosystems. In the wild, many seeds exhibit dormancy and will only germinate after exposure to certain environmental conditions. In contrast, crop seeds germinate as soon as they are imbibed usually at planting time. These domestication-triggered changes represent adaptations to cultivation and human harvesting. Germination is one of the common sets of traits recorded in different crops and termed the “domestication syndrome.” Moreover, legume seed imbibition has a crucial role in cooking properties. Different seed dormancy classes exist among plant species. Physical dormancy (often called hardseededness), as found in legumes, involves the development of a water-impermeable seed coat, caused by the presence of phenolics- and suberin-impregnated layers of palisade cells. The dormancy release mechanism primarily involves seed responses to temperature changes in the habitat, resulting in testa permeability to water. The underlying genetic controls in legumes have not been identified yet. However, positive correlation was shown between phenolics content (e.g., pigmentation), the requirement for oxidation and the activity of catechol oxidase in relation to pea seed dormancy, while epicatechin levels showed a significant positive correlation with soybean hardseededness. myeloblastosis family of transcription factors, WD40 proteins and enzymes of the anthocyanin biosynthesis pathway were involved in seed testa color in soybean, pea and Medicago, but were not tested directly in relation to seed dormancy. These phenolic compounds play important roles in defense against pathogens, as well as affecting the nutritional quality of products, and because of their health benefits, they are of industrial and medicinal interest. In this review, we discuss the role of the testa in mediating legume seed germination, with a focus on structural and chemical aspects. PMID:25101104

  3. Combining Drought Survival via Summer Dormancy and Annual Biomass Productivity in Dactylis glomerata L.

    PubMed Central

    Kallida, Rajae; Zhouri, Latifa; Volaire, Florence; Guerin, Adrien; Julier, Bernadette; Shaimi, Naima; Fakiri, Malika; Barre, Philippe

    2016-01-01

    Under Mediterranean climates, the best strategy to produce rain-fed fodder crops is to develop perennial drought resistant varieties. Summer dormancy present in native germplasm has been shown to confer a high level of survival under severe drought. Nevertheless it has also been shown to be negatively correlated with annual biomass productivity. The aim of this study was to analyze the correlations between summer dormancy and annual biomass productivity related traits and to identify quantitative trait loci (QTL) for these traits in a progeny of a summer dormant cocksfoot parent (Kasbah) and a summer active parent (Medly). A total of 283 offspring and the parents were phenotyped for summer dormancy, plant growth rate (PGR) and heading date in Morocco and for maximum leaf elongation rate (LERm) in France. The individuals were genotyped with a total of 325 markers including 59 AFLP, 64 SSR, and 202 DArT markers. The offspring exhibited a large quantitative variation for all measured traits. Summer dormancy showed a negative correlation with both PGR (-0.34 p < 0.005) and LERm (-0.27 p < 0.005). However, genotypes with both a high level of summer dormancy and a high level of PGR were detected in the progeny. One genetic map per parent was built with a total length of 377 and 423 cM for Kasbah and Medly, respectively. Both different and co-localized QTL for summer dormancy and PGR were identified. These results demonstrate that it should be possible to create summer dormant cocksfoot varieties with a high annual biomass productivity. PMID:26904054

  4. Physiological characteristics and related gene expression of after-ripening on seed dormancy release in rice.

    PubMed

    Du, W; Cheng, J; Cheng, Y; Wang, L; He, Y; Wang, Z; Zhang, H

    2015-11-01

    After-ripening is a common method used for dormancy release in rice. In this study, the rice variety Jiucaiqing (Oryza sativa L. subsp. japonica) was used to determine dormancy release following different after-ripening times (1, 2 and 3 months). Germination speed, germination percentage and seedling emergence increased with after-ripening; more than 95% germination and 85% seedling emergence were observed following 1 month of after-ripening within 10 days of imbibition, compared with <45% germination and 20% seedling emergence in freshly harvested seed. Hence, 3 months of after-ripening could be considered a suitable treatment period for rice dormancy release. Dormancy release by after-ripening is mainly correlated with a rapid decline in ABA content and increase in IAA content during imbibition. Subsequently, GA(1)/ABA, GA(7)/ABA, GA(12)/ABA, GA(20)/ABA and IAA/ABA ratios significantly increased, while GA(3)/ABA, GA(4)/ABA and GAs/IAA ratio significantly decreased in imbibed seeds following 3 months of after-ripening, thereby altering ?-amylase activity during seed germination. Peak ?-amylase activity occurred at an earlier germination stage in after-ripened seeds than in freshly harvested seeds. Expression of ABA, GA and IAA metabolism genes and dormancy-related genes was regulated by after-ripening time upon imbibition. Expression of OsCYP707A5, OsGA2ox1, OsGA2ox2, OsGA2ox3, OsILR1, OsGH3-2, qLTG3-1 and OsVP1 increased, while expression of Sdr4 decreased in imbibed seeds following 3 months of after-ripening. Dormancy release through after-ripening might be involved in weakening tissues covering the embryo via qLTG3-1 and decreased ABA signalling and sensitivity via Sdr4 and OsVP1. PMID:26205956

  5. The role of the testa during development and in establishment of dormancy of the legume seed.

    PubMed

    Smýkal, Petr; Vernoud, Vanessa; Blair, Matthew W; Soukup, Aleš; Thompson, Richard D

    2014-01-01

    Timing of seed germination is one of the key steps in plant life cycles. It determines the beginning of plant growth in natural or agricultural ecosystems. In the wild, many seeds exhibit dormancy and will only germinate after exposure to certain environmental conditions. In contrast, crop seeds germinate as soon as they are imbibed usually at planting time. These domestication-triggered changes represent adaptations to cultivation and human harvesting. Germination is one of the common sets of traits recorded in different crops and termed the "domestication syndrome." Moreover, legume seed imbibition has a crucial role in cooking properties. Different seed dormancy classes exist among plant species. Physical dormancy (often called hardseededness), as found in legumes, involves the development of a water-impermeable seed coat, caused by the presence of phenolics- and suberin-impregnated layers of palisade cells. The dormancy release mechanism primarily involves seed responses to temperature changes in the habitat, resulting in testa permeability to water. The underlying genetic controls in legumes have not been identified yet. However, positive correlation was shown between phenolics content (e.g., pigmentation), the requirement for oxidation and the activity of catechol oxidase in relation to pea seed dormancy, while epicatechin levels showed a significant positive correlation with soybean hardseededness. myeloblastosis family of transcription factors, WD40 proteins and enzymes of the anthocyanin biosynthesis pathway were involved in seed testa color in soybean, pea and Medicago, but were not tested directly in relation to seed dormancy. These phenolic compounds play important roles in defense against pathogens, as well as affecting the nutritional quality of products, and because of their health benefits, they are of industrial and medicinal interest. In this review, we discuss the role of the testa in mediating legume seed germination, with a focus on structural and chemical aspects. PMID:25101104

  6. ABA crosstalk with ethylene and nitric oxide in seed dormancy and germination

    PubMed Central

    Arc, Erwann; Sechet, Julien; Corbineau, Françoise; Rajjou, Loïc; Marion-Poll, Annie

    2013-01-01

    Dormancy is an adaptive trait that enables seed germination to coincide with favorable environmental conditions. It has been clearly demonstrated that dormancy is induced by abscisic acid (ABA) during seed development on the mother plant. After seed dispersal, germination is preceded by a decline in ABA in imbibed seeds, which results from ABA catabolism through 8′-hydroxylation. The hormonal balance between ABA and gibberellins (GAs) has been shown to act as an integrator of environmental cues to maintain dormancy or activate germination. The interplay of ABA with other endogenous signals is however less documented. In numerous species, ethylene counteracts ABA signaling pathways and induces germination. In Brassicaceae seeds, ethylene prevents the inhibitory effects of ABA on endosperm cap weakening, thereby facilitating endosperm rupture and radicle emergence. Moreover, enhanced seed dormancy in Arabidopsis ethylene-insensitive mutants results from greater ABA sensitivity. Conversely, ABA limits ethylene action by down-regulating its biosynthesis. Nitric oxide (NO) has been proposed as a common actor in the ABA and ethylene crosstalk in seed. Indeed, convergent evidence indicates that NO is produced rapidly after seed imbibition and promotes germination by inducing the expression of the ABA 8′-hydroxylase gene, CYP707A2, and stimulating ethylene production. The role of NO and other nitrogen-containing compounds, such as nitrate, in seed dormancy breakage and germination stimulation has been reported in several species. This review will describe our current knowledge of ABA crosstalk with ethylene and NO, both volatile compounds that have been shown to counteract ABA action in seeds and to improve dormancy release and germination. PMID:23531630

  7. Complex Combination of Seed Dormancy and Seedling Development Determine Emergence of Viburnum tinus (Caprifoliaceae)

    PubMed Central

    KARLSSON, LAILA M.; HIDAYATI, SITI N.; WALCK, JEFFREY L.; MILBERG, PER

    2004-01-01

    • Background and Aims The shrub Viburnum tinus is widely distributed in mattoral vegetation of the Mediterranean basin. The purpose of the present study was to classify the seed dormancy type and examine the requirements for embryo growth, root protrusion and shoot emergence. • Methods Overwintered fruits were collected in western Spain in April 2001 and prepared in three ways: entire pericarp was removed, exocarp and mesocarp were removed or fruits were left intact. Fruits treated in these three ways were subjected to artificial annual temperature cycles or to constant temperature regimes for 1·5 years. • Key Results Removal of exocarp and mesocarp was necessary for embryo growth and germination. High temperature favoured dormancy alleviation and embryo growth, intermediate to low temperatures favoured root protrusion, and intermediate temperature shoot emergence. There was substantial germination at constant temperature regimes, indicating an overlap between temperature intervals suitable for the different stages of embryo and seedling development. Functionally, V. tinus has the same root and shoot emergence pattern that is described for other Viburnum species considered to have epicotyl dormancy. However, the requirement for high and low temperatures for radicle protrusion and epicotyl emergence, respectively, was missing in V. tinus; these characters are the foundation for the epicotyl dormancy classification. • Conclusions It is concluded that V. tinus does not have epicotyl dormancy. Instead, there is a combination of a weak morphophysiological dormancy and a slow germination process, where different temperatures during an annual cycle favour different development stages. The present study suggests that the first complete seedlings would emerge in the field 1·5 years after fruit maturation in October, i.e. seed dispersal during winter, embryo growth during the first summer, root protrusion and establishment during the second autumn and winter, and cotyledon emergence during the second spring. PMID:15546926

  8. Seed Maturation Regulators Are Related to the Control of Seed Dormancy in Wheat (Triticum aestivum L.)

    PubMed Central

    Rikiishi, Kazuhide; Maekawa, Masahiko

    2014-01-01

    In Arabidopsis, the regulation network of the seed maturation program controls the induction of seed dormancy. Wheat EST sequences showing homology with the master regulators of seed maturation, LEAFY COTYLEDON1 (LEC1), LEC2 and FUSCA3 (FUS3), were searched from databases and designated respectively as TaL1L (LEC1-LIKE), TaL2L (LEC2-LIKE), and TaFUS3. TaL1LA, TaL2LA and TaFUS3 mainly expressed in seeds or embryos, with the expression limited to the early stages of seed development. Results show that tissue-specific and developmental-stage-dependent expressions are similar to those of seed maturation regulators in Arabidopsis. In wheat cultivars, the expression level of TaL1LA is correlated significantly with the germination index (GI) of whole seeds at 40 days after pollination (DAP) (r = –0.83**). Expression levels of TaFUS3 and TaL2LA are significantly correlated respectively with GIs at 40 DAP and 50 DAP, except for dormant cultivars. No correlation was found between the expression level of TaVP1, orthologue of ABA INSENSITIVE3 (ABI3), and seed dormancy. DELAY OF GERMINATION1 (DOG1) was identified as a quantitative trait locus (QTL) for the regulation of seed dormancy in Arabidopsis. Its promoter has RY motif, which is a target sequence of LEC2. Significant correlation was found between the expression of TaDOG1 and seed dormancy except for dormant cultivars. These results indicate that TaL1LA, TaL2LA, and TaFUS3 are wheat orthologues of seed maturation regulators. The expressions of these genes affect the level of seed dormancy. Furthermore, the pathways, which involve seed maturation regulators and TaDOG1, are important for regulating seed dormancy in wheat. PMID:25211528

  9. Progressive activation of paratrigeminal nucleus during entrance to hibernation

    SciTech Connect

    Kilduff, T.S.; Sharp, F.R.; Heller, H.C. Univ. of California, San Francisco Veterans Administration Medical Center, San Francisco, CA )

    1988-07-01

    The paratrigeminal nucleus (Pa5) undergoes a progressive increase in its uptake of 2-({sup 14}C)deoxyglucose (2DG) relative to other brain structures during entrance to hibernation in the ground squirrel. This highly significant increase results in the Pa5 becoming the most highly labeled brain region during hibernation, even though it exhibits one of the lowest levels of 2DG uptake in the brain during the nonhibernating state. The progressive activation of the Pa5 observed during entrance is reversed during arousal from hibernation. These observations and the neuroanatomical projections of the Pa5 implicate this nucleus as playing a role in the entrance and maintenance of the hibernating state.

  10. The University Entrance Exam that Diversified and the Problem

    NASA Astrophysics Data System (ADS)

    Kondo, Osamu

    The percentage of students who go on to universities or junior colleges is over fifty percent which is more than half of high school students. However the nation's birthrate is in decline and the total number of university-age children shows a declining tendency. Hence we cannot expect an increase in the number of applicants in the future. On the other hand, the number of universities has been increasing year by year. The competition among universities to survive is very fierce. The diversification of entrance examination is a symbol of this competition. By diversifying entrance exams, universities aimed at the quality of excellent students in the beginning. However, they have changed their direction to pursue the quantity of students. As of Today the entrance examination is losing its original starting function which means most or all applicants can enter universities. It is time all of the universities return to its starting line.

  11. Seed dormancy cycling in Arabidopsis: chromatin remodelling and regulation of DOG1 in response to seasonal environmental signals

    PubMed Central

    Footitt, Steven; Müller, Kerstin; Kermode, Allison R; Finch-Savage, William E

    2015-01-01

    The involvement of chromatin remodelling in dormancy cycling in the soil seed bank (SSB) is poorly understood. Natural variation between the winter and summer annual Arabidopsis ecotypes Cvi and Bur was exploited to investigate the expression of genes involved in chromatin remodelling via histone 2B (H2B) ubiquitination/de-ubiquitination and histone acetylation/deacetylation, the repressive histone methyl transferases CURLY LEAF (CLF) and SWINGER (SWN), and the gene silencing repressor ROS1 (REPRESSOR OF SILENCING1) and promoter of silencing KYP/SUVH4 (KRYPTONITE), during dormancy cycling in the SSB. ROS1 expression was positively correlated with dormancy while the reverse was observed for CLF and KYP/SUVH4. We propose ROS1 dependent repression of silencing and a sequential requirement of CLF and KYP/SUVH4 dependent gene repression and silencing for the maintenance and suppression of dormancy during dormancy cycling. Seasonal expression of H2B modifying genes was correlated negatively with temperature and positively with DOG1 expression, as were histone acetyltransferase genes, with histone deacetylases positively correlated with temperature. Changes in the histone marks H3K4me3 and H3K27me3 were seen on DOG1 (DELAY OF GERMINATION1) in Cvi during dormancy cycling. H3K4me3 activating marks remained stable along DOG1. During relief of dormancy, H3K27me3 repressive marks slowly accumulated and accelerated on exposure to light completing dormancy loss. We propose that these marks on DOG1 serve as a thermal sensing mechanism during dormancy cycling in preparation for light repression of dormancy. Overall, chromatin remodelling plays a vital role in temporal sensing through regulation of gene expression. PMID:25439058

  12. Seed dormancy cycling in Arabidopsis: chromatin remodelling and regulation of DOG1 in response to seasonal environmental signals.

    PubMed

    Footitt, Steven; Müller, Kerstin; Kermode, Allison R; Finch-Savage, William E

    2015-02-01

    The involvement of chromatin remodelling in dormancy cycling in the soil seed bank (SSB) is poorly understood. Natural variation between the winter and summer annual Arabidopsis ecotypes Cvi and Bur was exploited to investigate the expression of genes involved in chromatin remodelling via histone 2B (H2B) ubiquitination/de-ubiquitination and histone acetylation/deacetylation, the repressive histone methyl transferases CURLY LEAF (CLF) and SWINGER (SWN), and the gene silencing repressor ROS1 (REPRESSOR OF SILENCING1) and promoter of silencing KYP/SUVH4 (KRYPTONITE), during dormancy cycling in the SSB. ROS1 expression was positively correlated with dormancy while the reverse was observed for CLF and KYP/SUVH4. We propose ROS1 dependent repression of silencing and a sequential requirement of CLF and KYP/SUVH4 dependent gene repression and silencing for the maintenance and suppression of dormancy during dormancy cycling. Seasonal expression of H2B modifying genes was correlated negatively with temperature and positively with DOG1 expression, as were histone acetyltransferase genes, with histone deacetylases positively correlated with temperature. Changes in the histone marks H3K4me3 and H3K27me3 were seen on DOG1 (DELAY OF GERMINATION1) in Cvi during dormancy cycling. H3K4me3 activating marks remained stable along DOG1. During relief of dormancy, H3K27me3 repressive marks slowly accumulated and accelerated on exposure to light completing dormancy loss. We propose that these marks on DOG1 serve as a thermal sensing mechanism during dormancy cycling in preparation for light repression of dormancy. Overall, chromatin remodelling plays a vital role in temporal sensing through regulation of gene expression. PMID:25439058

  13. Blood chemistry of black bears from Pennsylvania during winter dormancy.

    PubMed

    Storm, G L; Alt, G L; Matula, G J; Nelson, R A

    1988-07-01

    Twenty-four serum chemistries were measured in blood samples collected from 20 adult female black bears (Ursus americanus) and their offspring, including 14 yearlings and 37 cubs, in northeastern Pennsylvania during winter 1984. Four other captive adult females were bled before, during, and after they were subjected to unseasonably warm temperatures during February. Levels of serum urea nitrogen (SUN) and creatinine were lower (P less than 0.05), and iron was higher (P less than 0.05) in male cubs compared to female cubs; serum chemistries were similar (P greater than or equal to 0.05) between sexes for yearlings. Total protein, albumin and creatinine levels increased with age of bears, whereas chloride, alkaline phosphatase, potassium, inorganic phosphorus and SUN/creatinine were higher (P less than 0.05) in cubs than in yearlings and adults. The relatively high serum calcium in cubs was probably related to rapid bone development and dietary intake of calcium during winter dormancy in cubs. Low serum calcium in adults was attributed to lactation and a lack of dietary intake. Urea/creatinine ratios averaged 5.5 and 4.6 for yearling females and males, respectively, 6.3 for adult females, and 29.0 and 22.8 for female and male cubs, respectively. Levels of serum chemistries of black bears apparently are relatively stable during winter denning, when bears are without food or water and do not urinate or defecate for several months. This stability indicates that black bears are resistant to the extremes in extrinsic environmental conditions. Abnormal blood chemistry values may indicate metabolic stresses that are not being controlled by bears.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:3411708

  14. Poliovirus infection transiently increases COPII vesicle budding.

    PubMed

    Trahey, Meg; Oh, Hyung Suk; Cameron, Craig E; Hay, Jesse C

    2012-09-01

    Poliovirus (PV) requires membranes of the host cell's secretory pathway to generate replication complexes (RCs) for viral RNA synthesis. Recent work identified the intermediate compartment and the Golgi apparatus as the precursors of the replication "organelles" of PV (N. Y. Hsu et al., Cell 141:799-811, 2010). In this study, we examined the effect of PV on COPII vesicles, the secretory cargo carriers that bud from the endoplasmic reticulum and homotypically fuse to form the intermediate compartment that matures into the Golgi apparatus. We found that infection by PV results in a biphasic change in functional COPII vesicle biogenesis in cells, with an early enhancement and subsequent inhibition. Concomitant with the early increase in COPII vesicle formation, we found an increase in the membrane fraction of Sec16A, a key regulator of COPII vesicle formation. We suggest that the early burst in COPII vesicle formation detected benefits PV by increasing the precursor pool required for the formation of its RCs. PMID:22740409

  15. Mechanical feedback stabilizes budding yeast morphogenesis

    NASA Astrophysics Data System (ADS)

    Banavar, Samhita; Trogdon, Michael; Petzold, Linda; Campas, Otger

    Walled cells have the ability to remodel their shape while sustaining an internal turgor pressure that can reach values up to 10 atmospheres. This requires a tight and simultaneous regulation of cell wall assembly and mechanochemistry, but the underlying mechanisms by which this is achieved remain unclear. Using the growth of mating projections in budding yeast (S. cerevisiae) as a motivating example, we have developed a theoretical description that couples the mechanics of cell wall expansion and assembly via a mechanical feedback. In the absence of a mechanical feedback, cell morphogenesis is inherently unstable. The presence of a mechanical feedback stabilizes changes in cell shape and growth, and provides a mechanism to prevent cell lysis in a wide range of conditions. We solve for the dynamics of the system and obtain the different dynamical regimes. In particular, we show that several parameters affect the stability of growth, including the strength of mechanical feedback in the system. Finally, we compare our results to existing experimental data.

  16. Tumor Budding in Upper Gastrointestinal Carcinomas

    PubMed Central

    Koelzer, Viktor H.; Langer, Rupert; Zlobec, Inti; Lugli, Alessandro

    2014-01-01

    The basis of personalized medicine in oncology is the prediction of an individual’s risk of relapse and death from disease. The presence of tumor budding (TB) at the tumor–host interface of gastrointestinal cancers has been recognized as a hallmark of unfavorable disease biology. TB is defined as the presence of dedifferentiated cells or small clusters of up to five cells at the tumor invasive front and can be observed in aggressive carcinomas of the esophagus, stomach, pancreas, ampulla, colon, and rectum. Presence of TB reproducibly correlates with advanced tumor stage, frequent lymphovascular invasion, nodal, and distant metastasis. The UICC has officially recognized TB as additional independent prognostic factor in cancers of the colon and rectum. Recent studies have also characterized TB as a promising prognostic indicator for clinical management of esophageal squamous cell carcinoma, adenocarcinoma of the gastro-esophageal junction, and gastric adenocarcinoma. However, several important issues have to be addressed for application in daily diagnostic practice: (1) validation of prognostic scoring systems for TB in large, multi-center studies, (2) consensus on the optimal assessment method, and (3) inter-observer reproducibility. This review provides a comprehensive analysis of TB in cancers of the upper gastrointestinal tract including critical appraisal of perspectives for further study. PMID:25177546

  17. Micropropagation of Helleborus through axillary budding.

    PubMed

    Beruto, Margherita; Viglione, Serena; Bisignano, Alessandro

    2013-01-01

    Helleborus genus, belonging to the Ranunculaceae family, has 20 species of herbaceous perennial flowering plants. The commercial exploitation of this plant is dependent on the selection and propagation of appropriate lines. High propagation rate could be accomplished by using a suitable tissue culture method enabling the rapid introduction of valuable selections in the market. However, in vitro cultivation of Helleborus is still very difficult. Thereby the development of reliable in vitro propagation procedures is crucial for future production systems. Axillary buds cultured on agar-solidified Murashige and Skoog medium supplemented with 1 mg/L benzyladenine, 0.1 mg/L β-naphthoxyacetic acid, and 2 mg/L isopentenyl adenine develop shoots after 16 weeks of culture under 16 h light regime, 50-60 μmol/s/m(2), and 19 ± 1°C. The multiplication rate ranges from 1.4 to 2.1. However, the genotype and the number of subcultures affect the efficiency of the micropropagation process. The rooting of shoots is about 80% in solidified MS medium containing 1 mg/L 1-naphthaleneacetic acid and 3 mg/L indole-3-butyric acid. The described protocol provides information which can contribute to the commercial production of Helleborus plants. PMID:23179705

  18. Studies on Cytokinin-Controlled Bud Formation in Moss Protonemata

    PubMed Central

    Brandes, H.; Kende, H.

    1968-01-01

    Application of cytokinins to moss protonemata of the proper physiological age causes bud formation on specific cells (caulonema). During the early stages of their development, buds revert to protonemal filaments if the cytokinin has been removed by washing the protonemata. This indicates that the hormone is not acting as a “trigger” but has to be present during a critical period of time until differentiation is stabilized. Autoradiographs of protonemata treated with a labeled cytokinin, benzyladenine-benzyl-7-14C, show a striking accumulation of the radioactivity in caulonema cells which are in the stage of bud formation, and in the buds themselves. Cells which did not react to the hormone contained very little radioactivity. The accumulation of benzyladenine in the “target cells” may be due to the presence of binding sites which, in turn, may distinguish responding cells from non-responding ones. Images PMID:16656847

  19. Oriented cell motility and division underlie early limb bud morphogenesis

    PubMed Central

    Wyngaarden, Laurie A.; Vogeli, Kevin M.; Ciruna, Brian G.; Wells, Mathew; Hadjantonakis, Anna-Katerina; Hopyan, Sevan

    2010-01-01

    The vertebrate limb bud arises from lateral plate mesoderm and its overlying ectoderm. Despite progress regarding the genetic requirements for limb development, morphogenetic mechanisms that generate early outgrowth remain relatively undefined. We show by live imaging and lineage tracing in different vertebrate models that the lateral plate contributes mesoderm to the early limb bud through directional cell movement. The direction of cell motion, longitudinal cell axes and bias in cell division planes lie largely parallel to one another along the rostrocaudal (head-tail) axis in lateral plate mesoderm. Transition of these parameters from a rostrocaudal to a mediolateral (outward from the body wall) orientation accompanies early limb bud outgrowth. Furthermore, we provide evidence that Wnt5a acts as a chemoattractant in the emerging limb bud where it contributes to the establishment of cell polarity that is likely to underlie the oriented cell behaviours. PMID:20554720

  20. Grapevine bud break prediction for cool winter climates

    NASA Astrophysics Data System (ADS)

    Nendel, Claas

    2010-05-01

    Statistical analysis of bud break data for grapevine ( Vitis vinifera L. cvs. Riesling and Müller-Thurgau) at 13 sites along the northern boundary of commercial grapevine production in Europe revealed that, for all investigated sites, the heat summation method for bud break prediction can be improved if the starting date for the accumulation of heat units is specifically determined. Using the coefficient of variance as a criterion, a global minimum for each site can be identified, marking the optimum starting date. Furthermore, it was shown that the application of a threshold temperature for the heat summation method does not lead to an improved prediction of bud break. Using site-specific parameters, bud break of grapevine can be predicted with an accuracy of ± 2.5 days. Using average parameters, the prediction accuracy is reduced to ± 4.5 days, highlighting the sensitivity of the heat summation method to the quality and the representativeness of the driving temperature data.