These are representative sample records from Science.gov related to your search topic.
For comprehensive and current results, perform a real-time search at Science.gov.
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

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...

3

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 ...

4

Epigenetic regulation of bud dormancy events in perennial plants  

PubMed Central

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

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

2014-01-01

5

Polyamine levels in buds and twigs of Tilia cordata from dormancy onset to bud break  

Microsoft Academic Search

The fluctuations of free and bound polyamines (PAs) were studied in vegetative buds and underlying twigs of linden (Tilia cordata L.) from August to May, to assess the connection between PA levels and seasonal cycles of growth and dormancy. Outer and inner\\u000a bud scales and shoot tips (short shoot tips with leaf initials in contiguous short internodes) were analyzed separately,

Arja Santanen; Liisa Kaarina Simola

2007-01-01

6

Dormancy in Reproductive Vegetative Buds in Creeping Perennials  

E-print Network

. Emergence was impaired in Cirsium arvense, Equisetum arvense, Sonchus arvensis and Tussilago farfara during a period in September-October. This seasonality was, however, not preserved in C. arvense root buds after temperature. None of the 12 combinations of photoperiods and temperatures used induced dormancy in C. arvense

7

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...

8

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...

9

[Relationship between breaking of dormancy and reactive oxygen species metabolism in flower buds of pear].  

PubMed

The metabolism of reactive oxygen species in pear (Pyrus bretschneideri Rehd.) flower buds changes greatly during their natural dormancy in winter. The O(-.)(2) production rate increases rapidly during the period of dormancy, but decreases when dormancy finishes (Fig. 5). H(2)O(2) content goes up significantly at the early stage of dormancy, but afterwards falls gradually (Fig. 5). However, ascorbic acid (AsA) and reduced glutathione (GSH) contents show a different changing trend: descending at first and keeping at relatively low levels during the process of dormancy, but rising during breaking of dormancy (Fig. 4). The activities of superoxide dismutase (SOD), ascorbic peroxidase (APX) and glutathione reductase (GR) descend during the process of dormancy, but rise during breaking of dormancy, although at different rates for different enzymes (Figs. 1, 3). On the contrary, the activity of catalase (CAT) increases sharply at the beginning of dormancy, keeps at a stable high level during dormancy, and gradually decreases at the end of dormancy period (Fig. 2). The activity of peroxidase (POD) even keeps increasing during dormancy and breaking of dormancy (Fig. 1). The results show that the metabolism of reactive oxygen species has certain strong correlation with the natural dormancy of pear flower buds in winter. PMID:15643086

Shao, Hao; Ma, Feng-Wang

2004-12-01

10

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

PubMed

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

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

2015-03-01

11

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

PubMed Central

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

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

2015-01-01

12

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...

13

Light and temperature sensing and signaling in induction of bud dormancy in woody plants  

Microsoft Academic Search

In woody species cycling between growth and dormancy must be precisely synchronized with the seasonal climatic variations.\\u000a Cessation of apical growth, resulting from exposure to short photoperiod (SD) and altered light quality, is gating the chain\\u000a of events resulting in bud dormancy and cold hardiness. The relative importance of these light parameters, sensed by phytochromes\\u000a and possibly a blue light

Jorunn E. Olsen

2010-01-01

14

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

PubMed Central

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

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

2012-01-01

15

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

PubMed

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

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

2011-02-01

16

Effects of "near-lethal" stress on bud dormancy and stem cold hardiness in red-osier dogwood.  

PubMed

We studied the effects of "near-lethal" (NL, 47 degrees C for 1 h) heat stress, applied to intact shoots of red-osier dogwood (Cornus sericea L.) during early (October), deep (November) or late (December) dormancy, on bud dormancy release and development of stem tissue cold hardiness under natural conditions and at a constant temperature of 0 or 23 degrees C in the dark. The NL heat-stress treatment overcame bud dormancy when applied during the early and late stages of dormancy. During October and December, all plants in the 23 degrees C + dark post-stress environment broke bud within 35 and 12 days, respectively, whereas the corresponding values for days to bud break in the control plants were more than 150 and 110 days, respectively. Application of NL heat stress during deep dormancy caused only slightly earlier bud break compared to the control plants. In the 0 degrees C + dark post-stress environment, all NL heat-treated plants died within 9 weeks. Under natural post-stress conditions, bud break in plants receiving NL heat stress during early and deep dormancy occurred at the same time as in control plants, whereas bud break of plants receiving NL heat stress during late dormancy occurred 55 days earlier than in control plants. Under both natural and 23 degrees C + dark post-stress conditions, cold hardiness of plants receiving NL heat stress during early dormancy was similar to that of controls. Application of NL heat stress during deep dormancy hastened the rate of deacclimation under the 23 degrees C + dark post-stress conditions but had no effect on deacclimation under natural post-stress conditions. Application of NL heat stress during late dormancy enhanced deacclimation of plants in both the 23 degrees C + dark and natural post-stress environments. PMID:14965968

Shirazi, A M; Fuchigami, L H

1995-04-01

17

Dormancy in Peach (Prunus persica L.) Flower Buds 1  

PubMed Central

Flower buds of peach (Prunus persica L.) trees, cv Novedad de Cordoba (Argentina), were collected near the end of the dormant period and immediately before anthesis. After removal of scale leaves, morphological observations of representative buds, made on transverse and longitudinal microtome sections, showed that all verticils making up the flower are present in an undifferentiated form during the dormant period (June). Flower buds collected at the end of dormant period (August) showed additional growth and differentiation, at which time formation of two ovules was beginning in the unicarpelar gynoecium. Dehiscence of anthers had not yet occurred 10 days before full bloom, and the ovules were still developing. Free endogenous gibberellin (GA)-like substances were quantified by bioassay (Tan-ginbozu dwarf rice microdrop) after SiO2 partition column chromatography, reversed phase C18-high performance liquid chromatography, and finally Nucleosil [N(CH3)2]high performance liquid chromatography. Bioactive fractions were then subjected to capillary gas chromatography-mass spectrometry-selected ion monitoring (GC-MS-SIM). Gibberellins A1, A3, and A8 were tentatively identified in peach flower buds using GC-SIM and Kovat's retention indices, and relative amounts approximated by GC-SIM (2:8:6 for GA1, GA3, and GA8, respectively). The highest concentration (330 nanograms per gram dry weight) of free GA1/GA3 was found in dormant buds (June) and diminished thereafter. The concentration free of GA1/GA3 did not increase immediately prior to bud break. However, high GA1/GA3 concentrations occurred during stages where rate of growth and cellular differentiation of (mainly fertile) verticils can be influenced. Images Figure 1 PMID:16667435

Luna, Virginia; Lorenzo, Eugenia; Reinoso, Herminda; Tordable, Maria C.; Abdala, Guillermina; Pharis, Richard P.; Bottini, Ruben

1990-01-01

18

Bud dormancy release in elm (Ulmus spp.) clones--a case study of photoperiod and temperature responses.  

PubMed

Dormancy release as influenced by duration of outdoor winter chilling in Florence (Italy) was studied under different photoperiodic and temperature treatments in collected twigs of two European (Ulmus glabra Huds. and Ulmus minor Mill.) and four Asian (Ulmus pumila L., Ulmus parvifolia Jacq., Ulmus macrocarpa Hance and Ulmus villosa Brandis) elm clones. Photoperiod had no effect on dormancy release, and there was no evidence that photoperiod affected bud burst during quiescence in the studied elm clones. Thermal time (day degrees >0 degrees C) to bud burst decreased in all the clones with increasing outdoor chilling. Although all the clones exhibited a rather weak dormancy, they significantly differed from each other. Dormancy was released earlier in the Asian than in the European clones, and the clones could be ranked from the U. pumila clone (very weak and short dormancy) to the U. minor clone (relatively stronger and longer dormancy), the other clones being intermediate. In all the clones except U. minor, the observed decrement in thermal time to bud burst was efficiently explained as an inverse exponential function of the number of chill days < or =5 degrees C received outdoor in autumn and winter. Endodormancy, as measured by the single-node cuttings test, was weak and short in all the clones. The latter result suggests that correlative inhibitions were largely responsible for preventing bud burst during winter in these elm clones. PMID:20022864

Ghelardini, Luisa; Santini, Alberto; Black-Samuelsson, Sanna; Myking, Tor; Falusi, Mauro

2010-02-01

19

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

PubMed Central

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

2013-01-01

20

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

PubMed

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

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

2014-07-01

21

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

PubMed Central

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

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

2014-01-01

22

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

PubMed Central

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 oxidation–reduction showed significant changes after GA4 treatment, which might promote dormancy release. We observed that genes at the mRNA level associated with energy metabolism and oxidation–reduction 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

Zhuang, Weibing; Gao, Zhihong; Zhang, Zhen

2013-01-01

23

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

PubMed

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 oxidation-reduction showed significant changes after GA4 treatment, which might promote dormancy release. We observed that genes at the mRNA level associated with energy metabolism and oxidation-reduction 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

Zhuang, Weibing; Gao, Zhihong; Wang, Liangju; Zhong, Wenjun; Ni, Zhaojun; Zhang, Zhen

2013-11-01

24

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...

25

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

PubMed Central

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

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

2015-01-01

26

Vernalization and the chilling requirement to exit bud dormancy: shared or separate regulation?  

PubMed Central

Similarities have long been recognized between vernalization, the prolonged exposure to cold temperatures that promotes the floral transition in many plants, and the chilling requirement to release bud dormancy in woody plants of temperate climates. In both cases the extended chilling period occurring during winter is used to coordinate developmental events to the appropriate seasonal time. However, whether or not these processes share common regulatory components and molecular mechanisms remain largely unknown. Both gene function and association genetics studies in Populus are beginning to answer this question. In Populus, studies have revealed that orthologs of the antagonistic flowering time genes FT and CEN/TFL1 might have central roles in both processes. We review Populus seasonal shoot development related to dormancy release and the floral transition and evidence for FT/TFL1-mediated regulation of these processes to consider the question of regulatory overlap. In addition, we discuss the potential for and challenges to integrating functional and population genomics studies to uncover the regulatory mechanisms underpinning these processes in woody plant systems. PMID:25566302

Brunner, Amy M.; Evans, Luke M.; Hsu, Chuan-Yu; Sheng, Xiaoyan

2014-01-01

27

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

PubMed

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

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

2014-10-01

28

Gene-expression profiling of grape bud response to two alternative dormancy-release stimuli expose possible links between impaired mitochondrial activity, hypoxia, ethylene-ABA interplay and cell enlargement  

Microsoft Academic Search

A grape-bud-oriented genomic platform was produced for a large-scale comparative analysis of bud responses to two stimuli\\u000a of grape-bud dormancy release, hydrogen cyanamide (HC) and heat shock (HS). The results suggested considerable similarity\\u000a in bud response to the stimuli, both in the repertoire of responding genes and in the temporary nature of the transcriptome\\u000a reprogramming. Nevertheless, the bud response to

Ron Ophir; Xuequn Pang; Tamar Halaly; Jaganatha Venkateswari; Shimon Lavee; David Galbraith; Etti

2009-01-01

29

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

SciTech Connect

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.

Potkar, Rewati; Recla, Jill [School of Forest Resources and Environmental Science, Michigan Technological University, 1400 Townsend Drive, Houghton, MI 49931 (United States)] [School of Forest Resources and Environmental Science, Michigan Technological University, 1400 Townsend Drive, Houghton, MI 49931 (United States); Busov, Victor, E-mail: vbusov@mtu.edu [School of Forest Resources and Environmental Science, Michigan Technological University, 1400 Townsend Drive, Houghton, MI 49931 (United States)] [School of Forest Resources and Environmental Science, Michigan Technological University, 1400 Townsend Drive, Houghton, MI 49931 (United States)

2013-02-15

30

BRANCHED1 Promotes Axillary Bud Dormancy in Response to Shade in Arabidopsis[C][W  

PubMed Central

Plants interpret a decrease in the red to far-red light ratio (R:FR) as a sign of impending shading by neighboring vegetation. This triggers a set of developmental responses known as shade avoidance syndrome. One of these responses is reduced branching through suppression of axillary bud outgrowth. The Arabidopsis thaliana gene BRANCHED1 (BRC1), expressed in axillary buds, is required for branch suppression in response to shade. Unlike wild-type plants, brc1 mutants develop several branches after a shade treatment. BRC1 transcription is positively regulated 4 h after exposure to low R:FR. Consistently, BRC1 is negatively regulated by phytochrome B. Transcriptional profiling of wild-type and brc1 buds of plants treated with simulated shade has revealed groups of genes whose mRNA levels are dependent on BRC1, among them a set of upregulated abscisic acid response genes and two networks of cell cycle– and ribosome-related downregulated genes. The downregulated genes have promoters enriched in TEOSINTE BRANCHED1, CYCLOIDEA, and PCF (TCP) binding sites, suggesting that they could be transcriptionally regulated by TCP factors. Some of these genes respond to BRC1 in seedlings and buds, supporting their close relationship with BRC1 activity. This response may allow the rapid adaptation of plants to fluctuations in the ratio of R:FR light. PMID:23524661

González-Grandío, Eduardo; Poza-Carrión, César; Sorzano, Carlos Oscar S.; Cubas, Pilar

2013-01-01

31

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...

32

BRANCHED1 promotes axillary bud dormancy in response to shade in Arabidopsis.  

PubMed

Plants interpret a decrease in the red to far-red light ratio (R:FR) as a sign of impending shading by neighboring vegetation. This triggers a set of developmental responses known as shade avoidance syndrome. One of these responses is reduced branching through suppression of axillary bud outgrowth. The Arabidopsis thaliana gene BRANCHED1 (BRC1), expressed in axillary buds, is required for branch suppression in response to shade. Unlike wild-type plants, brc1 mutants develop several branches after a shade treatment. BRC1 transcription is positively regulated 4 h after exposure to low R:FR. Consistently, BRC1 is negatively regulated by phytochrome B. Transcriptional profiling of wild-type and brc1 buds of plants treated with simulated shade has revealed groups of genes whose mRNA levels are dependent on BRC1, among them a set of upregulated abscisic acid response genes and two networks of cell cycle- and ribosome-related downregulated genes. The downregulated genes have promoters enriched in TEOSINTE BRANCHED1, CYCLOIDEA, and PCF (TCP) binding sites, suggesting that they could be transcriptionally regulated by TCP factors. Some of these genes respond to BRC1 in seedlings and buds, supporting their close relationship with BRC1 activity. This response may allow the rapid adaptation of plants to fluctuations in the ratio of R:FR light. PMID:23524661

González-Grandío, Eduardo; Poza-Carrión, César; Sorzano, Carlos Oscar S; Cubas, Pilar

2013-03-01

33

Variation in cold hardiness and carbohydrate concentration from dormancy induction to bud burst among provenances of three European oak species.  

PubMed

Although cold hardiness is known to be a major determinant of tree species distribution, its dynamics and the factors that regulate it remain poorly understood. Variation in cold hardiness and carbohydrate concentration, from dormancy induction until bud burst, were investigated in populations of two deciduous (Quercus robur L. and Quercus pubescens Willd.) and one evergreen (Quercus ilex L.) European oak. Mean cold hardiness values in January were -56, -45 and -27 degrees C for Q. robur, Q. pubescens and Q. ilex, respectively. Soluble carbohydrate concentrations were closely related to instantaneous cold hardiness, estimated by the electrolyte leakage method, whereas total carbohydrate concentration was related to maximum cold hardiness. Both cold hardiness and carbohydrate concentration showed a close linear relationship with temperatures at the location of the sampled population. Our results show that temporal variation in both the inter- and intraspecific cold hardiness in European oaks can be related to variations in the concentrations of soluble carbohydrates and that these relationships appear to be driven by temperature. PMID:17331900

Morin, Xavier; Améglio, Thierry; Ahas, Rein; Kurz-Besson, Cathy; Lanta, Vojtech; Lebourgeois, François; Miglietta, Franco; Chuine, Isabelle

2007-06-01

34

The dormancy-breaking stimuli "chilling, hypoxia and cyanamide exposure" up-regulate the expression of ?-amylase genes in grapevine buds.  

PubMed

It has been suggested that respiratory stress is involved in the mechanism underlying the dormancy-breaking effect of hydrogen cyanamide (H2CN2) and sodium azide in grapevine buds; indeed, reductions in oxygen levels (hypoxia) and inhibitors of respiration promote bud-break in grapevines. In this study, we showed that, hypoxia increased starch hydrolysis soluble sugar consumption and up-regulated the expression of ?-amylase genes (Vv?-AMYs) in grapevine buds, suggesting that these biochemical changes induced by hypoxia, may play a relevant role in the release of buds from endodormancy (ED). Three of the four Vv?-AMY genes that are expressed in grapevine buds were up-regulated by hypoxia and a correlation between changes in sugar content and level of Vv?-AMY gene expression during the hypoxia treatment was found, suggesting that soluble sugars mediate the effect of hypoxia on Vv?-AMY gene expression. Exogenous applications of soluble sugars and sugar analogs confirmed this finding and revealed that osmotic stress induces the expression of Vv?-AMY1 and Vv?-AMY3 and that soluble sugars induces Vv?-AMY2 and Vv?-AMY4 gene expression. Interestingly, the plant hormone gibberellic acid (GA3) induced the expression of Vv?-AMY3 and Vv?-AMY4 genes, while dormancy breaking stimuli, chilling and cyanamide exposure, mainly induced the expression of Vv?-AMY1 and Vv?-AMY2 genes, suggesting that these two ?-amylase genes might be involved in the release of grapevine buds from the ED. PMID:24594388

Rubio, Sebastián; Donoso, Amanda; Pérez, Francisco J

2014-03-15

35

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...

36

Extended Low Temperature Impacts Dormancy Status, Flowering Competence, and Transcript Profiles in Crown Buds of Leafy Spurge  

Technology Transfer Automated Retrieval System (TEKTRAN)

Leafy spurge (Euphorbia esula) is an herbaceous perennial weed that reproduces vegetatively from an abundance of underground adventitious buds. In this study we report the effects of different growth conditions on vegetative reproduction and flowering competence, and determine molecular mechanisms a...

37

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

PubMed Central

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

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

38

SEED DORMANCY IN LEAFY SPURGE  

Technology Transfer Automated Retrieval System (TEKTRAN)

Leafy spurge reproduces asexually via crown and root buds and sexually by seeds. Our unit has largely focused on dormancy in buds and vegetative reproduction. However, dormant seeds in the soil play a key role in the persistence of weeds. For example, leafy spurge seeds can remain dormant and viable...

39

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

PubMed Central

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-?-glucanase genes (glucan hydrolase family 17 [GH17]) in Populus that could turn over 1,3-?-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

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

2011-01-01

40

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...

41

Phylogenetic analysis and molecular evolution of the dormancy associated MADS-box genes from peach  

Microsoft Academic Search

BACKGROUND: Dormancy associated MADS-box (DAM) genes are candidates for the regulation of growth cessation and terminal bud formation in peach. These genes are not expressed in the peach mutant evergrowing, which fails to cease growth and enter dormancy under dormancy-inducing conditions. We analyzed the phylogenetic relationships among and the rates and patterns of molecular evolution within DAM genes in the

Sergio Jiménez; Amy L Lawton-Rauh; Gregory L Reighard; Albert G Abbott; Douglas G Bielenberg

2009-01-01

42

The expression of VvPHYA and VvPHYB transcripts is differently regulated by photoperiod in leaves and buds of grapevines  

PubMed Central

Light signals perceived by phytochromes (Phys) and cryptochromes (Crys) play key roles in plant growth and development and in photoperiod dependant process such as flowering, tuberization, seasonal growth cessation and dormancy. The integration of the light signals with the endogenous circadian oscillator provides plants with a mechanism to monitor changes in photo-period or day-length. In a recent report, we established that in Vitis vinifera L. cv Thompson Seedless, photoperiod drives the entrance of buds into endodormancy (ED) and modifies the expression of VvPHYA and VvPHYB transcripts in grapevine leaves, suggesting that both VvPHYs could play crucial roles in SD-induced transition of bud into ED. Here, we aimed to establish whether the transition of grapevine buds into ED is a mere consequence of a decision taken in the leaf or whether the bud responds by itself to photoperiod. Results show that in defoliated grapevine canes, bud-ED development is delayed compared with non-defoliated control canes, and that under LD-photoperiod both VvPHYA and VvPHYB transcripts are highly expressed in grapevine buds, whilst under SD-photoperiod both VvPHYs are downregulated and expression can not be detected. Overall, the results suggest that grapevine bud behaves as semi-autonomous organ in sensing the photoperiod signal, and that VvPHYA and VvPHYB gene expression is differently regulated by photoperiod in leaf and bud of grapevines. PMID:19820336

Kühn, Nathalie; Ormeño-Nuñez, Juan; Rubio, Sebastián

2009-01-01

43

IDENTIFICATION OF DIFFERENTIALLY-EXPRESSED GENES IN DORMANT AND GROWING BUDS OF LEAFY SPURGE (EUPHORBIA ESULA L.)  

Technology Transfer Automated Retrieval System (TEKTRAN)

Leafy spurge is an invasive perennial weed that proliferates from an abundance of underground adventitious buds. Dormancy in these buds contributes to persistence of leafy spurge and makes current control methods difficult. To identify genetic mechanisms regulating dormancy status, we developed two ...

44

Temperature efficiency for dormancy release in apricot varies when applied at different amounts of chill accumulation.  

PubMed

Our aim was to assess the possible differential effect of increasing temperatures due to global warming on dormancy progression in apricot. The effect of a range of chilling temperatures on vegetative and reproductive bud dormancy progression in excised shoots was examined during two seasons. Temperature treatments were applied in different dormant stages to evaluate the possible interaction of date?×?temperature for dormancy release in apricot. During sampling, chill accumulated in the field ranged from 0 to 49 chill portions (CPs), corresponding to 0-100% of the chilling requirement (CR) of the apricot selection Z505-2. Forcing conditions were applied after a 60-day chill treatment on each sampling date, and rate to budbreak (1/mean time to bud break: MTB(-1) ) was established in vegetative (terminal and lateral) and reproductive buds to determine depth of dormancy. Results showed that the stage of dormancy has a strong influence on the effect of different temperatures on dormancy progression in apricot. For the first time, a non-linear effect of different chilling temperatures during the dormancy cycle in apricot was obtained, especially in the superior range of temperatures traditionally considered to release dormancy. Thus, introduction of this differential effect could help to improve the models to estimate dormancy release in the context of climate change. PMID:22845025

Campoy, J A; Ruiz, D; Nortes, M D; Egea, J

2013-01-01

45

Gibberellins and Subapical Cell Divisions in Relation to Bud Set and Bud Break in Salix pentandra  

Microsoft Academic Search

.   In young plants of Salix pentandra, a temperate zone deciduous woody species, elongation growth ceases and a terminal bud is formed at day lengths shorter than\\u000a a critical length. This is the first step in dormancy development, making survival under harsh winter conditions possible.\\u000a Early studies strongly indicate that gibberellin is involved in the photoperiodic control of bud set

E. Hansen; J. E. Olsen; O. Junttila

1999-01-01

46

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...

47

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...

48

Seed dormancy and germination  

Microsoft Academic Search

Seed dormancy and germination are complex adaptive traits of higher plants that are influenced by a large number of genes and environmental factors. Studies of genetics and physiology have shown the important roles of the plant hormones abscisic acid and gibberellin in the regulation of dormancy and germination. More recently, the use of quantitative genetics and mutant approaches has allowed

Maarten Koornneef; Leónie Bentsink; Henk Hilhorst

2002-01-01

49

Effects of elevated CO2, nutrition and climatic warming on bud phenology in Sitka spruce (Picea sitchensis) and their impact on the risk of frost damage  

Microsoft Academic Search

Summary Effects of elevated COa, clone and plant nutrition on bud dormancy of Sitka spruce (Picea sitchensis (Bong.) Carr.) were examined. Sitka spruce seedlings were fumigated with ambient or elevated (ambient + 350 pmol mol-') concentrations of CO2 in open-top chambers for three growing seasons. In 1991 and 1992, elevated CO2 delayed bud burst in the spring and advanced bud

M. B. MURRAY; R. I. SMITH; I. D. LEITH; D. FOWLER; H. S. J. LEE; A. D. FRIEND; P. G. JARVIS

50

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...

51

Seed dormancy in alpine species  

PubMed Central

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

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

2011-01-01

52

Gibberellins and Subapical Cell Divisions in Relation to Bud Set and Bud Break in Salix pentandra.  

PubMed

In young plants of Salix pentandra, a temperate zone deciduous woody species, elongation growth ceases and a terminal bud is formed at day lengths shorter than a critical length. This is the first step in dormancy development, making survival under harsh winter conditions possible. Early studies strongly indicate that gibberellin is involved in the photoperiodic control of bud set and bud break. GA(1) action was studied by application under short days to plants where cessation of shoot elongation had occurred, followed by subsequent anatomic investigations of shoot tips. Under short days the frequency of cell division decreased rapidly along with the earlier observed decrease in GA(1) levels. Application of GA(1) to short-day-induced terminal buds rapidly stimulated cell division in apices several days before visible shoot elongation in response to this treatment was observed. One day after GA(1) application a fourfold increase in cell division frequency in apices was observed, increasing to a maximum of sevenfold 2 days after application. Long-day treatment leading to induction of bud break after about 4-6 days was followed by slowly increasing frequency of cell divisions. In earlier studies of this species, short days and gibberellins had no effect on cell elongation. These data show that increased GA(1) content, by application or long-day treatment, results in increased frequency of mitosis. This strongly indicates that GA(1) affects stem elongation in connection with bud set and bud break primarily by affecting cell divisions in subapical tissues. PMID:10688705

Hansen; Olsen; Junttila

1999-12-01

53

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:...

54

Dormancy in breast cancer  

PubMed Central

Tumor dormancy describes a prolonged quiescent state in which tumor cells are present, but disease progression is not yet clinically apparent. Breast cancer is especially known for long asymptomatic periods, up to 25 years, with no evidence of the disease, followed by a relapse. Factors that determine the cell’s decision to enter a dormant state and that control its duration remain unclear. In recent years, considerable progress has been made in understanding how tumor cells circulating in the blood interact and extravasate into secondary sites and which factors might determine whether these cells survive, remain dormant, or become macrometastases. The mechanisms of tumor cell dormancy are still not clear. Two different hypotheses are currently discussed: tumor cells persist either by completely withdrawing from the cell cycle or by continuing to proliferate at a slow rate that is counterbalanced by cell death. Because dormant disseminated tumor cells may be the founders of metastasis, one hypothesis is that dormant tumor cells, or at least a fraction of them, share stem cell-like characteristics that may be responsible for their long half-lives and their suggested resistance to standard chemotherapy. Therefore, knowledge of the biology of tumor cell dormancy may be the basis from which to develop innovative targeted therapies to control or eliminate this tumor cell fraction. In this review, we discuss biological mechanisms and clinical implications of tumor dormancy in breast cancer patients. PMID:24367205

Banys, Malgorzata; Hartkopf, Andreas D; Krawczyk, Natalia; Kaiser, Tatjana; Meier-Stiegen, Franziska; Fehm, Tanja; Neubauer, Hans

2012-01-01

55

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...

56

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...

57

Dormancy studies in blackberry seed  

E-print Network

been extensive, very little dealt with dormancy of blackberry seeds. Indeed, all the avail? able literature is limited to the practical side of the problem. As early as 1919 Rose (62) suggested that dormancy in Rubus idaeus was probably due... acid treatment was inadvisable. Hottes (39) stated that when raspberry and blackberry seeds are soaked in vinegar their germination will be hastened. Afanasiev (l), in suggesting means to overcome dormancy in blackberry (Rubus spp.),reported the seed...

Lasheen, Abdel Moty

1954-01-01

58

Release of apical dominance in potato tuber is accompanied by programmed cell death in the apical bud meristem.  

PubMed

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

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

2012-04-01

59

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

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

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

2014-01-01

60

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

PubMed Central

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

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

2014-01-01

61

GuestEntrance ASPAVEPARKINGFACILITY  

E-print Network

Entrance Stadium is a non-smoking facility (Designated smoking areas: Gates 1,5,7,11) Updated: 5. Public H. Nursing Medicine Pharmacy Architecture Business Education Fine Arts 25 Wheelchair Special-32 * * * * Programs - available at all gates open for public entranceP P P P P P P P Lost and Found (Gate 5 ticket

Oklahoma, University of

62

Sequencing and annotation of the evergrowing locus in peach [ Prunus persica (L.) Batsch] reveals a cluster of six MADS-box transcription factors as candidate genes for regulation of terminal bud formation  

Microsoft Academic Search

Buds are specialized structures that protect fragile meristematic regions during dormancy and are part of the mechanism that\\u000a plants use to survive unfavorable environmental conditions such as low temperature or dessication stress. The evergrowing (evg) mutant of peach [Prunus persica (L.) Batsch] does not form terminal vegetative buds in response to dormancy-inducing conditions such as short days and low\\u000a temperatures,

Douglas Gary Bielenberg; Zhigang Li; Tetyana Zhebentyayeva; Shenghua Fan; Gregory Lynn Reighard; Ralph Scorza; Albert Glenn Abbott

2008-01-01

63

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...

64

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...

65

Physiological processes during winter dormancy and their ecological significance  

SciTech Connect

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.

Havranek, W.M.; Tranquillini, W.

1995-07-01

66

Catalase inhibition accelerates dormancy release and sprouting in potato (Solanum tuberosum L.) tubers  

Microsoft Academic Search

The involvement of hydrogen peroxide (H2O2) metabolism in dormancy release and sprouting of potato (Solanum tuberosum L.) tubers has been investigated using three complementary approaches. In the fi rst approach, the evolution of the sprouting kinetics, H2O2 content and antioxidant enzyme activities were examined during tuber storage. The most important changes occurred at the « bud\\/sprout » level. In particular,

Mohammed Bajji; Frédéric Gastiny

2007-01-01

67

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

PubMed Central

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

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

68

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

PubMed

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

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

2014-01-01

69

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

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

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

2014-01-01

70

Differential expression of dehydrin in flower buds of two Japanese apricot cultivars requiring different chilling requirements for bud break.  

PubMed

In this study, we investigated seasonal changes in protein profiles in dormant flower buds of Japanese apricot (Prunus mume Siebold Zucc.) cultivars 'Ellching', from subtropical Taiwan, and 'Nanko', from temperate Japan. One protein, isolated by two-dimensional polyacrylamide gel electrophoresis of flower bud extracts, was shown by peptide sequencing to be a dehydrin (the group of D-11 LEA (late embryogenesis-abundant) proteins). Patterns of dehydrin protein and transcript accumulation differed between the cultivars, with greater accumulations and longer persistence in 'Nanko' than in 'Ellching'. These differences correspond with the greater requirement for chilling to break flower bud dormancy in 'Nanko' than in 'Ellching'. Our study supports the findings of earlier work comparing dehydrin expression in the bark tissue of the evergreen and deciduous peach (Prunus persica (L.) Batsch) genotypes, and suggests that the role of dehydrin during the dormant season is common to all Prunus species. PMID:17169895

Yamane, Hisayo; Kashiwa, Yukinobu; Kakehi, Eiko; Yonemori, Keizo; Mori, Hitoshi; Hayashi, Kyohei; Iwamoto, Kazuya; Tao, Ryutaro; Kataoka, Ikuo

2006-12-01

71

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

PubMed

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

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

2015-01-25

72

Interior, view of main entrance hall with main entrance door, ...  

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

Interior, view of main entrance hall with main entrance door, camera facing northeast - Naval Training Station, Senior Officers' Quarters District, Quarters No. 1, Naval Station Treasure Island, 1 Whiting Way, Yerba Buena Island, San Francisco, San Francisco County, CA

73

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

74

Bud development and hydraulics  

PubMed Central

The distal zone of one-year-old apple (Malus domestica) shoots was studied on five cultivars for bud size and composition (number of appendages) and hydraulic conductance before bud burst. Our hypothesis was that bud development was related to hydraulic conductance of the sap pathway to the bud independent of an acrotonic (proximal vs. distal) effect. Bud size and composition, and hydraulic conductance, were highly variable for all cultivars. A positive correlation was demonstrated between both the number of cataphylls and green-leaf primordia and hydraulic conductance. Cultivar and bud size affected the intercept of these relationships more than the slope suggesting similar scaling between these variables but different hydraulic efficiencies. A great proportion of small buds were also characterized by null values of hydraulic conductance. Our study suggests that hydraulically mediated competitions exist between adjacent buds within a same branching zone prefiguring the variability of lateral types in the following growing season. It is hypothesized that this developmental patterning is driven by hydraulic characteristics of the whole-metamer, including the subtending leaf, during bud development. PMID:19704779

Cochard, Hervé

2008-01-01

75

SUBTRACTIVE CDNA LIBRARIES IDENTIFY DIFFERENTIALLY EXPRESSED GENES IN DORMANT AND GROWING BUDS OF LEAFY SPURGE (EUPHORBIA ESULA)  

Technology Transfer Automated Retrieval System (TEKTRAN)

Two subtractive cDNA libraries were developed to study genes associated with bud dormancy (reverse library) and initiation of shoot growth (forward library) in leafy spurge. To identify unique sequences represented in each library, 15744 clones were screened to reduce the level of redundancy within ...

76

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 ...

77

Mitchell Entrance Open 24 Hours  

E-print Network

Comer Children's Hospital Future Parking Garage A P T Physical Therapy Level 1 Levels 1, 7Level 1 EW Accessible Entrance Entrance Valet Parking Elevator Pay on Foot Pharmacy Taxi Stand Stairs Bike Rack Under appointments at DCAM may use the main building entrance. · Comer Children's Hospital patients will be directed

Scherer, Norbert F.

78

Face recognition security entrance  

NASA Astrophysics Data System (ADS)

This paper describes an automatic face recognition algorithm for security entrances. There are two major steps in this procedure to make the automatic recognition possible: (1) We combined the two-phase face detection method and back propagation neural networks to detect human faces when people are walking in the region of entrances. The combination allows the strength of both methods activated to accommodate the size and head-orientation variations and to eliminate the false detection. (2) Novel face recognition: we extract the facial feature measurements to form the multi-variable normal distribution for each person. These multi-variable normal distributions separate the decision space well and the probability for good index for face recognition. This face recognition algorithm is very efficient on computing time and taking little storage space.

Ni, Catherine W.

2000-06-01

79

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...

80

Summer Dormancy in Perennial Temperate Grasses  

PubMed Central

• Background and Aims Dormancy has been extensively studied in plants which experience severe winter conditions but much less so in perennial herbaceous plants that must survive summer drought. This paper reviews the current knowledge on summer dormancy in both native and cultivated perennial temperate grasses originating from the Mediterranean Basin, and presents a unified terminology to describe this trait. • Scope Under severe drought, it is difficult to separate the responses by which plants avoid and tolerate dehydration from those associated with the expression of summer dormancy. Consequently, this type of endogenous (endo-) dormancy can be tested only in plants that are not subjected to moisture deficit. Summer dormancy can be defined by four criteria, one of which is considered optional: (1) reduction or cessation of leaf production and expansion; (2) senescence of mature foliage; (3) dehydration of surviving organs; and (4, optional) formation of resting organs. The proposed terminology recognizes two levels of summer dormancy: (a) complete dormancy, when cessation of growth is associated with full senescence of foliage and induced dehydration of leaf bases; and (b) incomplete dormancy, when leaf growth is partially inhibited and is associated with moderate levels of foliage senescence. Summer dormancy is expressed under increasing photoperiod and temperature. It is under hormonal control and usually associated with flowering and a reduction in metabolic activity in meristematic tissues. Dehydration tolerance and dormancy are independent phenomena and differ from the adaptations of resurrection plants. • Conclusions Summer dormancy has been correlated with superior survival after severe and repeated summer drought in a large range of perennial grasses. In the face of increasing aridity, this trait could be used in the development of cultivars that are able to meet agronomic and environmental goals. It is therefore important to have a better understanding of the genetic and environmental control of summer dormancy. PMID:17028299

VOLAIRE, FLORENCE; NORTON, MARK

2006-01-01

81

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

PubMed

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

Yoshie, Fumio

2014-05-01

82

Modelling Kiwifruit Budbreak as a Function of Temperature and Bud Interactions  

PubMed Central

This paper presents two models of budbreak on canes of ‘Hayward’ kiwifruit (Actinidia deliciosa). A conventional ‘chill unit’ (CU) type model is compared with an alternative ‘loss of potential’ (LOP) approach, which assumes that the number of buds developing in spring depends on climate and node position?dependent bud?to?bud interactions that vary in duration and intensity. Both models describe how temperature, and application of a dormancy?breaking chemical, determine the overall amount of budbreak for whole canes. However, the LOP model does so by describing patterns of budbreak along canes. To do this, the cumulative influence of distal neighbours is assumed to cause a progressive fall in the capacity for bud development over the autumn–winter period, an influence that gets stronger as temperature rises. The LOP model also assumes that the rate of decline varies along the cane, as a function of some inherent bud property. These two factors mean that buds towards the base of the cane break less often under the suppressive influence of distal neighbours, while low temperature (‘chilling’) increases budbreak by diminishing the intensity of suppression relative to bud development rate. Under this scenario, dormancy?breaking chemicals (such as hydrogen cyanamide, HC) enhance budbreak by diminishing the duration of suppression. Models were calibrated using daily temperature series and budbreak proportion data from a multi?year regional survey, and were then tested against independent data sets. Both models were run from a fixed start date until the time budbreak was almost complete, or until a standard date. The fitted models described 87 % of variation in amount of budbreak due to site, year, HC and node position effects in the original data set. Results suggest that the correlation between chilling and the amount of budbreak can be interpreted as a population?based phenomenon based on interaction among buds. PMID:12102525

AUSTIN, P. T.; HALL, A. J.; SNELGAR, W. P.; CURRIE, M. J.

2002-01-01

83

Project BudBurst  

NSDL National Science Digital Library

Project BudBurst is an interactive website that has people recording their observations of growing plants. You monitor the plants progress and record it on the website. there is a section for teachers about how to implement BudBurst in the classroom, and it includes classroom activities for grades Kindergarten to 12th grade. This section includes activities on how to observe plants, climate affect on plants, and an activity on ecosystems and biomes.

2007-01-01

84

Virus Maturation by Budding  

PubMed Central

Enveloped viruses mature by budding at cellular membranes. It has been generally thought that this process is driven by interactions between the viral transmembrane proteins and the internal virion components (core, capsid, or nucleocapsid). This model was particularly applicable to alphaviruses, which require both spike proteins and a nucleocapsid for budding. However, genetic studies have clearly shown that the retrovirus core protein, i.e., the Gag protein, is able to form enveloped particles by itself. Also, budding of negative-strand RNA viruses (rhabdoviruses, orthomyxoviruses, and paramyxoviruses) seems to be accomplished mainly by internal components, most probably the matrix protein, since the spike proteins are not absolutely required for budding of these viruses either. In contrast, budding of coronavirus particles can occur in the absence of the nucleocapsid and appears to require two membrane proteins only. Biochemical and structural data suggest that the proteins, which play a key role in budding, drive this process by forming a three-dimensional (cage-like) protein lattice at the surface of or within the membrane. Similarly, recent electron microscopic studies revealed that the alphavirus spike proteins are also engaged in extensive lateral interactions, forming a dense protein shell at the outer surface of the viral envelope. On the basis of these data, we propose that the budding of enveloped viruses in general is governed by lateral interactions between peripheral or integral membrane proteins. This new concept also provides answers to the question of how viral and cellular membrane proteins are sorted during budding. In addition, it has implications for the mechanism by which the virion is uncoated during virus entry. PMID:9841669

Garoff, Henrik; Hewson, Roger; Opstelten, Dirk-Jan E.

1998-01-01

85

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...

86

GENETICS OF SEED DORMANCY IN WEEDY RICE  

Technology Transfer Automated Retrieval System (TEKTRAN)

We have developed weedy rice as an experimental system to investigate genetic and evolutionary mechanisms underlying seed dormancy, a key adaptive or domestication-related trait. Dormancy is very strong for most weedy accessions, strong for some traditional cultivars, and weak for modern cultivars, ...

87

Development of dormancy in different lily genotypes regenerated in vitro  

Microsoft Academic Search

Dormancy development in four Lilium genotypes,L. speciosum, Star Gazer, C. King and Snow Queenregenerated in vitro was compared. Major factorsinfluencing dormancy development were the same for different genotypes andespecially L. speciosum and Star Gazer, that are closelyrelated, reacted similarly. Temperature was the main factor in dormancyinduction and breaking. The range of temperatures that induced dormancy and thelevel of dormancy that

M. M. Langens-Gerrits; S. Nashimoto; A. F. Croes; G. J. De Klerk

2001-01-01

88

EARLY ENTRANCE COPRODUCTION PLANT  

SciTech Connect

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.

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

89

EARLY ENTRANCE COPRODUCTION PLANT  

SciTech Connect

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.

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

90

EARLY ENTRANCE COPRODUCTION PLANT  

SciTech Connect

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.

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

91

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

PubMed

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

Wisniewski, Michael; Norelli, John; Artlip, Timothy

2015-01-01

92

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

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

Wisniewski, Michael; Norelli, John; Artlip, Timothy

2015-01-01

93

Mycobacterium tuberculosis: Success through dormancy  

PubMed Central

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

Gengenbacher, Martin; Kaufmann, Stefan H. E.

2012-01-01

94

EARLY ENTRANCE COPRODUCTION PLANT  

SciTech Connect

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.

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

2001-03-21

95

Mechanisms Governing Metastatic Dormancy and Reactivation  

PubMed Central

Summary Many cancer patients suffer from metastatic relapse several years after they have undergone radical surgery. Early cancer cell dissemination followed by a protracted period of dormancy potentially explains this prevalent clinical behavior. Increasing evidence suggests that the metastasis-initiating cells are cancer stem cells or functionally equivalent to cancer stem cells. Here, I discuss newly uncovered mechanisms governing metastatic dormancy and reactivation, placing emphasis on tumor evolution, stem cell signaling, and micro-environmental niches. In spite of significant remaining uncertainties, these findings provide a framework to understand the logic of metastatic dormancy and reactivation and open new avenues for therapeutic intervention. PMID:24209616

Giancotti, Filippo G.

2015-01-01

96

"Bud, Not Buddy."  

ERIC Educational Resources Information Center

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…

Brodie, Carolyn S.

2002-01-01

97

EARLY ENTRANCE COPRODUCTION PLANT  

SciTech Connect

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.

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

98

EARLY ENTRANCE COPRODUCTION PLANT  

SciTech Connect

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.

John Anderson; Charles Schrader

2004-01-26

99

EARLY ENTRANCE COPRODUCTION PLANT  

SciTech Connect

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.

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

100

Studies in Wild Oat Seed Dormancy  

PubMed Central

A selected strain of wild oat (Avena fatua L.) seed has been shown to lose dormancy rapidly during moist soil incubation at 25 C, whereas seed kept similarly at 5 C maintained a high level of dormancy. The activities of cytosolic dehydrogenase enzymes of the pentose phosphate pathway were assayed throughout a period of moist soil incubation at these two temperatures. A distinction was made between extractable dehydrogenases from the embryo and the endosperm regions of the caryopsis. Dehydrogenase activities monitored in seeds incubated at 25 C gradually increased over the course of the investigation. The largest increases in activity occurred during incubation at 5 C, the situation in which dormancy is maintained. No obvious connection could be found between dormancy breakage and increased activity of the pentose phosphate pathway dehydrogenases. PMID:16661860

Adkins, Stephen W.; Ross, James D.

1981-01-01

101

Differential floral development and gene expression in grapevines during long and short photoperiods suggests a role for floral genes in dormancy transitioning.  

PubMed

Daylength is an important environmental cue for synchronizing growth, flowering, and dormancy with seasonality. As many floral development genes are photoperiod regulated, it has been suggested that they could have a regulatory role in bud endodormancy. Therefore, the influence of photoperiod was studied on inflorescence primordia differentiation and floral pathway related gene expression during the development of overwintering buds in Vitis riparia and V. spp. 'Seyval'. Photoperiod treatments were imposed 35 days after budbreak, and histological and transcriptomic analyses were conducted during the subsequent 42 days of bud development. Long day (LD, 15 h) and short day (SD, 13 h) buds were floral competent by 21 days of photoperiod treatment (56 days after budbreak); however, the floral meristem developed faster in LD than in SD buds. Analysis of 132 floral pathway related genes represented on the Affymetrix Grape Genome array indicated 60 were significantly differentially expressed between photoperiod treatments. Genes predominantly related to floral transition or floral meristem development were identified by their association with distinct grape floral meristem development and an expression pattern in LD consistent with their previously identified roles in flowering literature. Genes with a potential dual role in floral development and dormancy transitioning were identified using photoperiod induced differences in floral development between LD and SD buds and uncharacteristic gene expression trends in relation to floral development. Candidate genes with the potential to play a dual role in SD dormancy induction include circadian rhythm or flowering transition related genes: AP2, BT1, COL-13, EIN3, ELF4, DDTR, GAI and HY5. PMID:20151315

Sreekantan, Lekha; Mathiason, Kathy; Grimplet, Jérôme; Schlauch, Karen; Dickerson, Julie A; Fennell, Anne Y

2010-05-01

102

Seed dormancy distribution: explanatory ecological factors  

PubMed Central

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

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

2012-01-01

103

Making an Entrance. Teaching Art with Art.  

ERIC Educational Resources Information Center

Provides a discussion on entrance designs to interest students in the history of architecture. Focuses on reasons why studying entrances is important. Includes pictures of four different entrances to show students the diversity of entrances and offer examples to give student ideas for their work. (CMK)

Hubbard, Guy

2001-01-01

104

Genetic analysis of embryo dormancy. Final report  

SciTech Connect

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.

Galau, G.

1998-09-01

105

EARLY ENTRANCE COPRODUCTION PLANT  

SciTech Connect

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.

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

2003-04-16

106

EARLY ENTRANCE COPRODUCTION PLANT  

SciTech Connect

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.

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

2003-09-15

107

EARLY ENTRANCE COPRODUCTION PLANT  

SciTech Connect

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.

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

108

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

PubMed Central

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

2011-01-01

109

EARLY ENTRANCE COPRODUCTION PLANT  

SciTech Connect

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

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

2004-01-12

110

14 CFR 204.7 - Revocation for dormancy.  

Code of Federal Regulations, 2010 CFR

... 2010-01-01 2010-01-01 false Revocation for dormancy. 204.7 Section 204.7 Aeronautics and Space ...DETERMINATIONS Filing Requirements § 204.7 Revocation for dormancy. (a) An air carrier that has not commenced...

2010-01-01

111

Hormonal and molecular events during seed dormancy release and germination  

E-print Network

Hormonal and molecular events during seed dormancy release and germination Gerhard Leubner on Seeds, Salamanca, Spain, 12-16 May 2002 Symposium Seed Dormancy and Germination #12;Leubner-Metzger (2003) - page 2 Introduction Seed germination of species with 'coat-imposed' dormancy is determined

Leubner, Gerhard

112

ISOLATION OF THREE DORMANCY QTLS AS MENDELIAN FACTORS IN RICE  

Technology Transfer Automated Retrieval System (TEKTRAN)

Seed dormancy is a key adaptive trait under polygenic control in many plants. We introduced dormancy genes from the weedy rice accession SS18-2 into the non-dormant genetic background of EM93-1 rice to examine component genes and afterripening effects of individual QTLs on dormancy and germination. ...

113

Transcript profiling in Vitis riparia during chilling requirement fulfillment reveals coordination of gene expression patterns with optimized bud break.  

PubMed

Endodormant grapevine buds require a period of chilling before they break and begin to grow. Custom Vitis bud cDNA microarrays (9,216 features) were used to examine gene expression patterns in overwintering Vitis riparia buds during 2,000 h of 4 degrees C chilling. Three-node cuttings collected concurrently with buds were monitored to determine dormancy status. Chilling requirement was fulfilled after 1,500 h of chilling; however, 2,000 h of chilling significantly increased the rate of bud break. Microarray analysis identified 1,469 significantly differentially expressed (p value < 0.05) array features when 1,000, 1,500, and 2,000 h of chilling were compared to 500 h of chilling. Functional classification revealed that the majority of genes were involved in metabolism, cell defense/stress response, and genetic information processing. The number of significantly differentially expressed genes increased with chilling hour accumulation. The expression of a group of 130 genes constantly decreased during the chilling period. Up-regulated genes were not detected until the later stages of chilling accumulation. Hierarchical clustering of non-redundant expressed sequence tags revealed inhibition of genes involved in carbohydrate and energy metabolism and activation of genes involved in signaling and cell growth. Clusters with expression patterns associated with increased chilling and bud break were identified, indicating several candidate genes that may serve as indicators of bud chilling requirement fulfillment. PMID:18633655

Mathiason, Kathy; He, Dong; Grimplet, Jérôme; Venkateswari, J; Galbraith, David W; Or, Etti; Fennell, Anne

2009-02-01

114

Colon Cryptogenesis: Asymmetric Budding  

PubMed Central

The process of crypt formation and the roles of Wnt and cell-cell adhesion signaling in cryptogenesis are not well described; but are important to the understanding of both normal and cancer colon crypt biology. A quantitative 3D-microscopy and image analysis technique is used to study the frequency, morphology and molecular topography associated with crypt formation. Measurements along the colon reveal the details of crypt formation and some key underlying biochemical signals regulating normal colon biology. Our measurements revealed an asymmetrical crypt budding process, contrary to the previously reported symmetrical fission of crypts. 3D immunofluorescence analyses reveals heterogeneity in the subcellular distribution of E-cadherin and ?-catenin in distinct crypt populations. This heterogeneity was also found in asymmetrical budding crypts. Singular crypt formation (i.e. no multiple new crypts forming from one parent crypt) were observed in crypts isolated from the normal colon mucosa, suggestive of a singular constraint mechanism to prevent aberrant crypt production. The technique presented improves our understanding of cryptogenesis and suggests that excess colon crypt formation occurs when Wnt signaling is perturbed (e.g. by truncation of adenomatous polyposis coli, APC protein) in most colon cancers. PMID:24205248

Tan, Chin Wee; Hirokawa, Yumiko; Gardiner, Bruce S.; Smith, David W.; Burgess, Antony W.

2013-01-01

115

Colon cryptogenesis: asymmetric budding.  

PubMed

The process of crypt formation and the roles of Wnt and cell-cell adhesion signaling in cryptogenesis are not well described; but are important to the understanding of both normal and cancer colon crypt biology. A quantitative 3D-microscopy and image analysis technique is used to study the frequency, morphology and molecular topography associated with crypt formation. Measurements along the colon reveal the details of crypt formation and some key underlying biochemical signals regulating normal colon biology. Our measurements revealed an asymmetrical crypt budding process, contrary to the previously reported symmetrical fission of crypts. 3D immunofluorescence analyses reveals heterogeneity in the subcellular distribution of E-cadherin and ?-catenin in distinct crypt populations. This heterogeneity was also found in asymmetrical budding crypts. Singular crypt formation (i.e. no multiple new crypts forming from one parent crypt) were observed in crypts isolated from the normal colon mucosa, suggestive of a singular constraint mechanism to prevent aberrant crypt production. The technique presented improves our understanding of cryptogenesis and suggests that excess colon crypt formation occurs when Wnt signaling is perturbed (e.g. by truncation of adenomatous polyposis coli, APC protein) in most colon cancers. PMID:24205248

Tan, Chin Wee; Hirokawa, Yumiko; Gardiner, Bruce S; Smith, David W; Burgess, Antony W

2013-01-01

116

PtABI3 Impinges on the Growth and Differentiation of Embryonic Leaves during Bud Set in Poplar  

PubMed Central

The Arabidopsis ABSCISIC ACID–INSENSITIVE3 (ABI3) protein plays a crucial role during late seed development and has an additional function at the vegetative meristem, particularly during periods of growth-arresting conditions and quiescence. Here, we show that the ABI3 homolog of poplar (PtABI3) is expressed in buds during natural bud set. Expression occurs clearly after perception of the critical daylength that initiates bud set and dormancy in poplar. In short-day conditions mimicking natural bud set, the expression of a chimeric PtABI3::?-glucuronidase (GUS) gene occurred in those organs and cells of the apex that grow actively but will undergo arrest: the young embryonic leaves, the subapical meristem, and the procambial strands. If PtABI3 is overexpressed or downregulated, bud development in short-day conditions is altered. Constitutive overexpression of PtABI3 resulted in apical buds with large embryonic leaves and small stipules, whereas in antisense lines, bud scales were large and leaves were small. Thus, PtABI3 influences the size and ratio of embryonic leaves and bud scales/stipules that differentiate from the primordia under short-day conditions. These observations, together with the expression of PtABI3::GUS in embryonic leaves but not in bud scales/stipules, support the idea that wild-type PtABI3 is required for the relative growth rate and differentiation of embryonic leaves inside the bud. These experiments reveal that ABI3 plays a role in the cellular differentiation of vegetative tissues, in addition to its function in seeds. PMID:12172029

Rohde, Antje; Prinsen, Els; De Rycke, Riet; Engler, Gilbert; Van Montagu, Marc; Boerjan, Wout

2002-01-01

117

Expression analysis of phytochromes A, B and floral integrator genes during the entry and exit of grapevine-buds from endodormancy.  

PubMed

A common molecular regulatory pathway that involves PHYA, PHYB and floral integrator genes CONSTANS (CO), FLOWERING LOCUS T (FT) and SUPRESSOR OF OVEREXPRESSION OF CO1 (SOC1) has been suggested to participate in the regulation of photoperiod dependent processes such as flowering and dormancy. In grapevines (Vitis vinifera L.), decreasing photoperiod and low temperatures trigger the transition of buds into endodormancy (ED), a process that is accompanied by drastic changes in gene expression of VvPHYA and B in leaves. To analyse the relationship of VvPHYA, VvPHYB, and grape homologues of Arabidopsis floral integrator genes VvCO, VvFT, VvMADS8, with ED, a comparative expression analysis of these genes was performed in grapevine-leaves and buds before, during and after the transition of buds into ED. The expression of all the above genes in the bud-tissue, and the fact that photoperiod regulates differently the expression of VvPHYA and B in buds than in leaves, suggests that the bud might be an autonomous or semi-autonomous organ in perceiving and transducing the photoperiod signal. On the other hand, the coordinated down-regulation of VvFT in leaves and buds during the transition of buds into ED, and its subsequent up-regulation following the application of dormancy-breaking compounds, hydrogen cyanamide (HC) and sodium azide, suggests that VvFT could play a key role in stimulating bud-growth by repressing their entry into ED. PMID:21453983

Pérez, Francisco J; Kühn, N; Vergara, R

2011-09-15

118

Coat Proteins and Vesicle Budding  

Microsoft Academic Search

The trafficking of proteins within eukaryotic cells is achieved by the capture of cargo and targeting molecules into vesicles that bud from a donor membrane and deliver their contents to a receiving compartment. This process is bidirectional and may involve multiple organelles within a cell. Distinct coat proteins mediate each budding event, serving both to shape the transport vesicle and

Randy Schekman; Lelio Orci

1996-01-01

119

On dormancy strategies in tardigrades.  

PubMed

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

Guidetti, Roberto; Altiero, Tiziana; Rebecchi, Lorena

2011-05-01

120

Circadian Clock Components Regulate Entry and Affect Exit of Seasonal Dormancy as Well as Winter Hardiness in Populus Trees1[W][OA  

PubMed Central

This study addresses the role of the circadian clock in the seasonal growth cycle of trees: growth cessation, bud set, freezing tolerance, and bud burst. Populus tremula × Populus tremuloides (Ptt) LATE ELONGATED HYPOCOTYL1 (PttLHY1), PttLHY2, and TIMING OF CAB EXPRESSION1 constitute regulatory clock components because down-regulation by RNA interference of these genes leads to altered phase and period of clock-controlled gene expression as compared to the wild type. Also, both RNA interference lines show about 1-h-shorter critical daylength for growth cessation as compared to the wild type, extending their period of growth. During winter dormancy, when the diurnal variation in clock gene expression stops altogether, down-regulation of PttLHY1 and PttLHY2 expression compromises freezing tolerance and the expression of C-REPEAT BINDING FACTOR1, suggesting a role of these genes in cold hardiness. Moreover, down-regulation of PttLHY1 and PttLHY2 causes a delay in bud burst. This evidence shows that in addition to a role in daylength-controlled processes, PttLHY plays a role in the temperature-dependent processes of dormancy in Populus such as cold hardiness and bud burst. PMID:20530613

Ibáñez, Cristian; Kozarewa, Iwanka; Johansson, Mikael; Ögren, Erling; Rohde, Antje; Eriksson, Maria E.

2010-01-01

121

Seed Dormancy in Red Rice 1  

PubMed Central

The weak acid character of many previously identified, but otherwise chemically dissimilar, dormancy-breaking compounds may contribute to their physiological activity. To test this idea, short chain monocarboxylic acids of one to six carbons, for which no previous reports of such activity exist, were incubated with dormant, dehulled red rice (Oryza sativa) seeds. Greater than 90% germination was observed after 24 hours of imbibition with 19 millimolar formic, 53 millimolar acetic, 20 millimolar propionic, 28 millimolar butyric, 20 millimolar valeric, or 16 millimolar caproic acid followed by 7 to 14 days incubation on water at 30°C. Dormancy-breaking activity was pH-dependent. Incubation medium pH values that favored formation of the protonated species resulted in the highest germination percentages. There was no promotive effect of medium pH itself in the range of 3 to 7. In contrast, germination of intact seeds was less than 40% in the presence of 55 millimolar monocarboxylic acids at pH 3, unless seeds were partially dry-afterripened. The pH-dependent activity of these acids was maintained during afterripening of intact seeds. The results are consistent with the idea that the dissociable proton of weak acids is responsible for their dormancy-breaking activity. Many other weak acids may break seed dormancy but have been over-looked due to the rigid pH dependence necessary for activity. PMID:16665509

Cohn, Marc Alan; Chiles, Lisa A.; Hughes, John A.; Boullion, Karen J.

1987-01-01

122

ESCRT requirements for EIAV budding  

PubMed Central

Background Retroviruses and many other enveloped viruses usurp the cellular ESCRT pathway to bud from cells. However, the stepwise process of ESCRT-mediated virus budding can be challenging to analyze in retroviruses like HIV-1 that recruit multiple different ESCRT factors to initiate budding. Results In this study, we characterized the ESCRT factor requirements for budding of Equine Infectious Anemia Virus (EIAV), whose only known direct ESCRT protein interaction is with ALIX. siRNA depletion of endogenous ESCRT proteins and “rescue” experiments with exogenous siRNA-resistant wild type and mutant constructs revealed budding requirements for the following ESCRT proteins: ALIX, CHMP4B, CHMP2A and VPS4A or VPS4B. EIAV budding was inhibited by point mutations that abrogate the direct interactions between ALIX:CHMP4B, CHMP4B:CHMP2A, and CHMP2A:VPS4A/B, indicating that each of these interactions is required for EIAV budding. Unexpectedly, CHMP4B depletion led to formation of multi-lobed and long tubular EIAV virions. Conclusions We conclude that EIAV budding requires an ESCRT protein network that comprises EIAV Gag-ALIX-CHMP4B-CHMP2A-VPS4 interactions. Our experiments also suggest that CHMP4B recruitment/polymerization helps control Gag polymerization and/or processing to ensure that ESCRT factor assembly and membrane fission occur at the proper stage of virion assembly. These studies help establish EIAV as a streamlined model system for dissecting the stepwise processes of lentivirus assembly and ESCRT-mediated budding. PMID:24107264

2013-01-01

123

Differential dormancy of co-occurring copepods  

NASA Astrophysics Data System (ADS)

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.

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

1998-08-01

124

Proteomic approach to analyze dormancy breaking of tree seeds.  

PubMed

In forest broadleaves from the temperate zone, a large number of species exhibit seed dormancy phenomena. Tree seeds show some of the most pronounced and complicated forms of dormancy in the plant kingdom. Many seeds are deeply physiologically dormant whatever their moisture level and age. However, dormancy can usually be overcome by a cold or warm stratification for several months. The transition from seed dormancy to germination is a multi-step process. In combination with the availability of genome sequence data, proteomics has opened up enormous possibilities for identifying the total set of expressed proteins as well as expression changes during dormancy breaking. The proteomic approach used for analysis of dormancy breaking of tree seeds offers new data allowing better understanding of the mechanism of deep physiological dormancy. The results of proteomic studies on dormancy breaking and the presence of abscisic and gibberellic acids in tree seeds (beech Fagus sylvatica L., Norway maple Acer platanoides L. and sycamore Acer pseudoplatanus L.), help to explain this process better. Most of the changes in protein expression were observed at the end of stratification and in the germinated seeds. This is the most active period of dormancy breaking when seeds pass from the quiescent state to germination. The analysis of the proteins' function showed that the mechanism of seed dormancy breaking involves many processes. Energy metabolism, proteasome, transcription, protein synthesis, signal transduction and methionine metabolism proteins have a special importance. PMID:20306286

Paw?owski, Tomasz Andrzej

2010-05-01

125

Internal tides in Dixon Entrance  

NASA Astrophysics Data System (ADS)

Semidiurnal (M2) internal tides are studied in and near Dixon Entrance. Two complementary approaches are presented: a data analysis and a numerical study. the data consist of current records as well as hydrographic profiles. The derived baroclinic velocities represent a considerable portion of the total signal. The baroclinic velocities change little in time and variations in the vertical suggest the presence of a vertical mode. A nonlinear, frictionless, two-layer, finite-difference numerical model forced by a barotropic tidal wave was applied over an idealized topography representing Dixon Entrance. Specifically, Dixon Entrance was modelled as a coastal east-west oriented, shallow channel connected to a deep flat open ocean through a very steep continental slope. Several numerical experiments are presented. The main result the model offers is a possible explanation, in terms of waves, of the generation of internal tides. The passage of long barotropic Kelvin waves travelling north on the the open ocean triggers a baroclinic diffraction process which gives rise to cylindrical Poincare waves travelling towards the deep ocean, westward, Kelvin waves propagating along the coast, northward, and Kelvin waves propagating inside the channel, eastward. This wave pattern was described by Buchwald (1971). The Kelvin wave pattern always seems to be present inside the channel; however, internal waves are very sensitive to variations in the topography, and waves of short wavelengths are also generated. It was possible from the numerical experiments to explain some of the features found in the data analysis. The velocity magnitudes and main generation regions were comparable. The results of the model were unable to explain the detail of the quasi-steady pattern of baroclinic currents.

Carrasco, Ana Consuelo

1998-11-01

126

Un-“ESCRT”-ed Budding  

PubMed Central

In their recent publication, Rossman et al. [1] describe how the inherent budding capability of its M2 protein allows influenza A virus to bypass recruitment of the cellular ESCRT machinery enlisted by several other enveloped RNA and DNA viruses, including HIV, Ebola, rabies, herpes simplex type 1 and hepatitis B. Studies from the same laboratory [2] and other laboratories [3–6] indicate that budding of plasmid-derived virus-like particles can be mediated by the influenza virus hemagglutinin and neuraminidase proteins in the absence of M2. These events are also independent of canonical ESCRT components [2,7]. Understanding how intrinsic properties of these influenza virus proteins permit ESCRT-independent budding expands our understanding of the budding process itself. PMID:21666754

Yondola, Mark; Carter, Carol

2011-01-01

127

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

PubMed

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

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

2007-03-01

128

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

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 18°C. Bud4 overexpression also affected septin organization during bud growth in shs1? cells at 30°C. 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

Wu, Huan; Guo, Jia; Zhou, Ya-Ting; Gao, Xiang-Dong

2015-03-01

129

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

PubMed Central

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

2014-01-01

130

Ecological mechanisms involved in dormancy breakage in Ulex parviflorus seeds  

Microsoft Academic Search

Dormancy in the hard seed coats of Mediterranean species is considered a strategy that enables persistent seed banks to be\\u000a formed in the soil. An important factor related to seed coat fracture and dormancy breakage in Mediterranean ecosystems is\\u000a heat. Nevertheless, the effect of factors other than heat on dormancy breakage in these species has hardly been studied. To\\u000a investigate

M. J. Baeza; V. R. Vallejo

2006-01-01

131

CARBOHYDRATES AFFECT DORMANCY AND GROWTH IN UNDERGROUND BUDS OF LEAFY SPURGE  

Technology Transfer Automated Retrieval System (TEKTRAN)

The term “low-carb diet” is frequently mentioned by a health conscious society interested in reducing carbohydrate intake. What are carbohydrates? In general, carbohydrates are either simple sugars like glucose, fructose, and sucrose (table sugar) or complexes of sugars like starch. Carbohydrates ar...

132

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 ...

133

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...

134

Dynamic thermal time model of cold hardiness for dormant grapevine buds  

PubMed Central

Background and Aims Grapevine (Vitis spp.) cold hardiness varies dynamically throughout the dormant season, primarily in response to changes in temperature. The development and possible uses of a discrete-dynamic model of bud cold hardiness for three Vitis genotypes are described. Methods Iterative methods were used to optimize and evaluate model parameters by minimizing the root mean square error between observed and predicted bud hardiness, using up to 22 years of low-temperature exotherm data. Three grape cultivars were studied: Cabernet Sauvignon, Chardonnay (both V. vinifera) and Concord (V. labruscana). The model uses time steps of 1 d along with the measured daily mean air temperature to calculate the change in bud hardiness, which is then added to the hardiness from the previous day. Cultivar-dependent thermal time thresholds determine whether buds acclimate (gain hardiness) or deacclimate (lose hardiness). Key Results The parameterized model predicted bud hardiness for Cabernet Sauvignon and Chardonnay with an r2 = 0·89 and for Concord with an r2 = 0·82. Thermal time thresholds and (de-)acclimation rates changed between the early and late dormant season and were cultivar dependent but independent of each other. The timing of these changes was also unique for each cultivar. Concord achieved the greatest mid-winter hardiness but had the highest deacclimation rate, which resulted in rapid loss of hardiness in spring. Cabernet Sauvignon was least hardy, yet maintained its hardiness latest as a result of late transition to eco-dormancy, a high threshold temperature required to induce deacclimation and a low deacclimation rate. Conclusions A robust model of grapevine bud cold hardiness was developed that will aid in the anticipation of and response to potential injury from fluctuations in winter temperature and from extreme cold events. The model parameters that produce the best fit also permit insight into dynamic differences in hardiness among genotypes. PMID:21212090

Ferguson, John C.; Tarara, Julie M.; Mills, Lynn J.; Grove, Gary G.; Keller, Markus

2011-01-01

135

School of Law Entrance Scholarships SCHOOL OF LAW ENTRANC E SCHOLARSHIP REGULATI ONS FOR 2009  

E-print Network

School of Law Entrance Scholarships SCHOOL OF LAW ENTRANC E SCHOLARSHIP REGULATI ONS FOR 2009 BACKGROUND The School of Law Entrance Scholarships were established by the School of Law to assist students with the cost of studying in their first year of law at the University of Waikato. Up to five Scholarships

Waikato, University of

136

ORIGINAL PAPER Environmental control of ovarian dormancy in natural  

E-print Network

and North America enter an adult ovarian dormancy in response to short days and low temperatures. The inde of ovarian dormancy in D. mela- nogaster from two natural populations representing latitu- dinal extremes in eastern North America (Florida at 27°N and Maine at 44°N). In both natural populations, tempera- ture

Oregon, University of

137

Seed dormancy and germination—emerging mechanisms and new hypotheses  

PubMed Central

Seed dormancy has played a significant role in adaptation and evolution of seed plants. While its biological significance is clear, molecular mechanisms underlying seed dormancy induction, maintenance and alleviation still remain elusive. Intensive efforts have been made to investigate gibberellin and abscisic acid metabolism in seeds, which greatly contributed to the current understanding of seed dormancy mechanisms. Other mechanisms, which might be independent of hormones, or specific to the seed dormancy pathway, are also emerging from genetic analysis of “seed dormancy mutants.” These studies suggest that chromatin remodeling through histone ubiquitination, methylation and acetylation, which could lead to transcription elongation or gene silencing, may play a significant role in seed dormancy regulation. Small interfering RNA and/or long non-coding RNA might be a trigger of epigenetic changes at the seed dormancy or germination loci, such as DELAY OF GERMINATION1. While new mechanisms are emerging from genetic studies of seed dormancy, novel hypotheses are also generated from seed germination studies with high throughput gene expression analysis. Recent studies on tissue-specific gene expression in tomato and Arabidopsis seeds, which suggested possible “mechanosensing” in the regulatory mechanisms, advanced our understanding of embryo-endosperm interaction and have potential to re-draw the traditional hypotheses or integrate them into a comprehensive scheme. The progress in basic seed science will enable knowledge translation, another frontier of research to be expanded for food and fuel production. PMID:24904627

Nonogaki, Hiroyuki

2014-01-01

138

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...

139

Tansley review Seed dormancy and the control of germination  

E-print Network

(GA), scarification, and various technologies for seed enhancement like priming (Benech-Arnold, 2004; Halmer, 2004). However, while seed enhancements like priming may overcome dormancy to improveTansley review Seed dormancy and the control of germination William E. Finch-Savage1 and Gerhard

Leubner, Gerhard

140

Candidate Cave Entrances on Mars  

NASA Astrophysics Data System (ADS)

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.

Cushing, Glen

2012-04-01

141

Candidate cave entrances on Mars  

USGS Publications Warehouse

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.

Cushing, Glen E.

2012-01-01

142

Foamy Virus Budding and Release  

PubMed Central

Like all other viruses, a successful egress of functional particles from infected cells is a prerequisite for foamy virus (FV) spread within the host. The budding process of FVs involves steps, which are shared by other retroviruses, such as interaction of the capsid protein with components of cellular vacuolar protein sorting (Vps) machinery via late domains identified in some FV capsid proteins. Additionally, there are features of the FV budding strategy quite unique to the spumaretroviruses. This includes secretion of non-infectious subviral particles and a strict dependence on capsid-glycoprotein interaction for release of infectious virions from the cells. Virus-like particle release is not possible since FV capsid proteins lack a membrane-targeting signal. It is noteworthy that in experimental systems, the important capsid-glycoprotein interaction could be bypassed by fusing heterologous membrane-targeting signals to the capsid protein, thus enabling glycoprotein-independent egress. Aside from that, other systems have been developed to enable envelopment of FV capsids by heterologous Env proteins. In this review article, we will summarize the current knowledge on FV budding, the viral components and their domains involved as well as alternative and artificial ways to promote budding of FV particle structures, a feature important for alteration of target tissue tropism of FV-based gene transfer systems. PMID:23575110

Hütter, Sylvia; Zurnic, Irena; Lindemann, Dirk

2013-01-01

143

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...

144

Entrance to Yosemite Valley in Fog  

USGS Multimedia Gallery

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....

145

Pend Oreille Entrance Improvements Swift Company Team  

E-print Network

and confusion. · Transform the entrance/gateway to the University in a scale and character appropriate campus #12;Project Zone: campus entry zone #12;#12;Project Zone: Pend Oreille Road #12;#12;Landscape

Van Volkenburgh, Elizabeth

146

Myogenic determination occurs independently in somites and limb buds.  

PubMed

Gene targeting has indicated that the bHLH transcription factors Myf-5 and MyoD are required for myogenic determination because skeletal myoblasts and myofibers are entirely ablated in mouse embryos lacking both Myf-5 and MyoD. Entrance into the skeletal myogenic program during development occurs following the independent transcriptional induction of either Myf-5 or MyoD. To identify sequences required for the de novo induction of MyoD transcription during development, we investigated the expression patterns of MyoD-lacZ transgenes in embryos deficient in both Myf-5 and MyoD. We observed that a 258-bp fragment containing the core of the -20-kb MyoD enhancer activated expression in newly formed somites and limb buds in compound mutant embryos lacking both Myf-5 and MyoD. Importantly, Myf-5- and MyoD-deficient presumptive muscle precursor cells expressing beta-galactosidase were observed to assume nonmuscle fates primarily as precartilage primordia in the trunk and the limbs, suggesting that these cells were multipotential. Therefore, cells are recruited into the MyoD-dependent myogenic lineage through activation of the -20-kb MyoD enhancer and this occurs independently in somites and limb buds. PMID:9986734

Kablar, B; Krastel, K; Ying, C; Tapscott, S J; Goldhamer, D J; Rudnicki, M A

1999-02-15

147

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

PubMed

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

Gao, Feng; Ayele, Belay T

2014-01-01

148

Functional genomics of seed dormancy in wheat: advances and prospects  

PubMed Central

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

Gao, Feng; Ayele, Belay T.

2014-01-01

149

Stratification requirements for seed dormancy alleviation in a wetland weed.  

PubMed

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 (?) and oxygen levels. We also determined how stratification temperatures, moisture levels and durations contributed to dormancy release. Stratification released dormancy by decreasing base ? 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 ??=?0 MPa increased GR compared to stratification at lower water potentials, demonstrating that ? 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

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

2013-01-01

150

Stratification Requirements for Seed Dormancy Alleviation in a Wetland Weed  

PubMed Central

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 (?) and oxygen levels. We also determined how stratification temperatures, moisture levels and durations contributed to dormancy release. Stratification released dormancy by decreasing base ? 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 ??=?0 MPa increased GR compared to stratification at lower water potentials, demonstrating that ? 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

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

2013-01-01

151

CHEMICALLY FORCED DORMANCY TERMINATION MIMICS NATURAL DORMANCY PROGRESSION IN POTATO TUBER MERISTEMS BY REDUCING ABA LEVELS AND MODIFYING EXPRESSION OF GENES INVOLVED IN REGULATING ABA CONTENT.  

Technology Transfer Automated Retrieval System (TEKTRAN)

The length of potato tuber dormancy depends on both the genotype and environmental conditions during growth and storage. Abscisic acid (ABA) has been shown to play a critical role in tuber dormancy control but the mechanisms regulating ABA content during dormancy as well as the sites of ABA synthesi...

152

Eyeing emergence: modified treatments for terminating dormancy of conifer seeds.  

PubMed

Many seeds of coniferous species display a deep primary dormancy at maturity and require several weeks of pretreatment to produce seed populations that germinate in a vigorous and timely manner. Facilitating an efficient transition from dormancy to germination by devising improved protocols for dormancy breakage is not only important to conifer seed research, aiding in the study of the dormancy process itself, but is also of interest and applicability to commercial forest nursery operations. In the forests of British Columbia, Canada, several conifer species are well-adapted to their environment, with seeds needing to experience long durations in the moist state at cool or fluctuating temperatures. These include yellow-cedar (Callitropsis nootkatensis), western white pine (Pinus monticola), and true fir species, such as Pacific silver fir and subalpine fir (Abies amabilis and A. lasiocarpa, respectively). In this chapter, we discuss the development of new dormancy-breaking protocols for the aforementioned species that centre on the balance of several key aspects: (1) reducing the time needed to terminate dormancy in the seed population; (2) synchronicity of germination; (3) ease of use; (4) cost-effectiveness; and (5) repeatability. Where possible, any new or modified protocol should be further tested in relationship to promoting rapid seedling growth in a forest nursery greenhouse setting and after planting at natural stands. Based on the five criteria listed above, very significant improvements compared to traditional dormancy-breaking methods have been achieved for the targeted conifer species. Where tested (e.g. yellow-cedar), the modified dormancy-breaking treatments result in vigorous growth in the greenhouse and after planting at natural stands. PMID:21898249

Feurtado, J Allan; Kermode, Allison R

2011-01-01

153

Metabolic Dormancy and Responses to Environmental Desiccation in Fish Embryos  

Microsoft Academic Search

\\u000a Metabolic depression is relatively uncommon among the fishes with the greatest number of species exhibiting dormancy as embryos.\\u000a Dormancy in fish embryos is largely associated with deposition of embryos into terrestrial habitats to avoid embryo predation\\u000a or to survive intermittent drying of aquatic habitats. Killifish embryos in general, and especially the embryos of annual\\u000a killifish, are highly adapted for life

Jason E. Podrabsky; Angèle Tingaud-Sequeira; Joan Cerdà

154

Oxidative signaling in seed germination and dormancy  

PubMed Central

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

El-Maarouf-Bouteau, Hayat

2008-01-01

155

The perivascular niche regulates breast tumor dormancy  

PubMed Central

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-?1 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

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

156

Seed Dormancy in Red Rice 1  

PubMed Central

Sodium nitrite at 10 millimolar breaks dormancy of dehulled red rice (Oryza sativa). While germination is light independent, low pH conditions (pH 3) are required for maximum response. Water and buffer controls at pH 3 remain dormant. The response to nitrite occurs at 25 and 30°C but is reduced at 20°C, although nondormant seeds germinate readily at this temperature. The contact time for response to nitrite is less than 2 h at the start of imbibition. Seeds imbibed first in water show reduced germination when subsequently transferred to nitrite. Dehulled seeds show little or no response to nitrate and ammonium ions. Intact seeds remain dormant in the presence of nitrite or nitrate unless partially dry-afterripened. The pH dependence of nitrite sensitivity is reduced in intact, afterripening seeds. In highly dormant seeds, vacuum infiltration experiments suggest that the hull restricts uptake of nitrite. PMID:16663224

Cohn, Marc Alan; Butera, Denise L.; Hughes, John A.

1983-01-01

157

Dormancy in the stem cell niche  

PubMed Central

Tissues characterized by constant turnover contain post-mitotic, terminally differentiated cells originating from highly proliferative progenitors, which in turn derive from a relatively small population of stem cells. At the population level, self-renewal and differentiation are the possible outcomes of stem cell proliferation; overall, however, stem cells are quiescent if compared with their direct progeny. The recent discovery of a particularly quiescent, or dormant, subpopulation of hematopoietic stem cells (HSCs) raises a number of fundamental questions. As stem cell fate is influenced by the signals integrated by the stem cell niche, will dormant HSCs reside in specific dormant niches? Is the mechanism of dormancy common to multiple regenerating tissues or specific to the hematopoietic system? If cancer is maintained by a few cancer stem cells, do they also contain a subpopulation of dormant cells, and could this be exploited for therapeutic purposes? PMID:22429750

2012-01-01

158

Dormancy in the stem cell niche.  

PubMed

Tissues characterized by constant turnover contain post-mitotic, terminally differentiated cells originating from highly proliferative progenitors, which in turn derive from a relatively small population of stem cells. At the population level, self-renewal and differentiation are the possible outcomes of stem cell proliferation; overall, however, stem cells are quiescent if compared with their direct progeny. The recent discovery of a particularly quiescent, or dormant, subpopulation of hematopoietic stem cells (HSCs) raises a number of fundamental questions. As stem cell fate is influenced by the signals integrated by the stem cell niche, will dormant HSCs reside in specific dormant niches? Is the mechanism of dormancy common to multiple regenerating tissues or specific to the hematopoietic system? If cancer is maintained by a few cancer stem cells, do they also contain a subpopulation of dormant cells, and could this be exploited for therapeutic purposes? PMID:22429750

Sottocornola, Roberta; Lo Celso, Cristina

2012-01-01

159

Bacterial Persister Cell Formation and Dormancy  

PubMed Central

Bacterial cells may escape the effects of antibiotics without undergoing genetic change; these cells are known as persisters. Unlike resistant cells that grow in the presence of antibiotics, persister cells do not grow in the presence of antibiotics. These persister cells are a small fraction of exponentially growing cells (due to carryover from the inoculum) but become a significant fraction in the stationary phase and in biofilms (up to 1%). Critically, persister cells may be a major cause of chronic infections. The mechanism of persister cell formation is not well understood, and even the metabolic state of these cells is debated. Here, we review studies relevant to the formation of persister cells and their metabolic state and conclude that the best model for persister cells is still dormancy, with the latest mechanistic studies shedding light on how cells reach this dormant state. PMID:24038684

Knabel, Stephen J.; Kwan, Brian W.

2013-01-01

160

Bacterial persister cell formation and dormancy.  

PubMed

Bacterial cells may escape the effects of antibiotics without undergoing genetic change; these cells are known as persisters. Unlike resistant cells that grow in the presence of antibiotics, persister cells do not grow in the presence of antibiotics. These persister cells are a small fraction of exponentially growing cells (due to carryover from the inoculum) but become a significant fraction in the stationary phase and in biofilms (up to 1%). Critically, persister cells may be a major cause of chronic infections. The mechanism of persister cell formation is not well understood, and even the metabolic state of these cells is debated. Here, we review studies relevant to the formation of persister cells and their metabolic state and conclude that the best model for persister cells is still dormancy, with the latest mechanistic studies shedding light on how cells reach this dormant state. PMID:24038684

Wood, Thomas K; Knabel, Stephen J; Kwan, Brian W

2013-12-01

161

Using Generic Data to Establish Dormancy Failure Rates  

NASA Technical Reports Server (NTRS)

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.

Reistle, Bruce

2014-01-01

162

Effects of Dormancy Regulating Chemicals on Innate and Salinity Induced Dormancy in the Invasive Prosopis juliflora (Sw.) DC. Shrub  

Microsoft Academic Search

The effect of different types and concentrations of dormancy regulating chemicals (DRCs) on innate and induced dormancy was evaluated under optimal germination conditions in the invasive Prosopis juliflora shrub. Lower concentrations of gibberellic acid (0.3 mM) and kinetin (0.05 mM) were more effective in enhancing germination % and rate at higher concentrations of NaCl, but the reverse was true for thiourea. None

Ali-El-Keblawy; Fatima Al-Ansari; Awatif Al-Rawai

2005-01-01

163

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

PubMed

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

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

164

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

PubMed

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

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

2014-11-01

165

Experimental evolution in budding yeast  

NASA Astrophysics Data System (ADS)

I will discuss our progress in analyzing evolution in the budding yeast, Saccharomyces cerevisiae. We take two basic approaches. The first is to try and examine quantitative aspects of evolution, for example by determining how the rate of evolution depends on the mutation rate and the population size or asking whether the rate of mutation is uniform throughout the genome. The second is to try to evolve qualitatively novel, cell biologically interesting phenotypes and track the mutations that are responsible for the phenotype. Our efforts include trying to alter cell morphology, evolve multicellularity, and produce a biological oscillator.

Murray, Andrew

2012-02-01

166

Review of Tumor Dormancy Therapy Using Traditional Oriental Herbal Medicine  

PubMed Central

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.

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

2013-01-01

167

Cellular Factors Required for Lassa Virus Budding  

Microsoft Academic Search

It is known that Lassa virus Z protein is sufficient for the release of virus-like particles (VLPs) and that it has two L domains, PTAP and PPPY, in its C terminus. However, little is known about the cellular factor for Lassa virus budding. We examined which cellular factors are used in Lassa virus Z budding. We demonstrated that Lassa Z

S. Urata; T. Noda; Yoshihiro Kawaoka; Hideyoshi Yokosawa; Jiro Yasuda

2006-01-01

168

The University Entrance Examination System in China  

ERIC Educational Resources Information Center

Every year, millions of high school students sit the Chinese national university entrance exam, and their results determine entry into universities or alternatives such as employment. Limited information about the exam is available in the Western literature even though it determines the future of millions of young people, and is increasingly of…

Davey, Gareth; De Lian, Chuan; Higgins, Louise

2007-01-01

169

The Power and Magic of Entrances.  

ERIC Educational Resources Information Center

Explores the theme of "entrances" in children's literature and film from the physical, emotional, and symbolic perspectives. Materials containing each type of theme are suggested. Programming ideas for developing the theme using art, storytelling, dramatic play, and creative writing activities are provided. A resource list including 91 books and…

Zingher, Gary

1994-01-01

170

An Entrance Region Mass Transfer Experiment.  

ERIC Educational Resources Information Center

This paper describes an experiment designed to reveal the consequences of the development of a concentration boundary layer. The rate of a mass transfer limited electrochemical reaction is measured and used to obtain the dependence of average Sherwood number on Reynolds number and entrance length. (Author/BB)

Youngquist, G. R.

1979-01-01

171

A novel preclinical murine model of immune-mediated metastatic dormancy  

PubMed Central

The mechanisms underlying cancer dormancy are poorly understood. We have developed a preclinical murine model in which immunosurveillance restrains spontaneous metastases in permanent dormancy. The model faithfully recapitulates human metastatic dormancy and may be useful to decipher the immune mechanisms constraining disease progression, thereby facilitating the development of novel immunotherapeutic approaches to control metastatic disease. PMID:25083338

Romero, Irene; Garrido, Federico; Garcia-Lora, Angel M

2014-01-01

172

Rapid and Effective Germination Methods for Overcoming Seed Dormancy in Annual Canarygrass  

Microsoft Academic Search

Mediterranean climates (P. aquatica) (Carlson et al., 1996). Dormancy in pedigreed Phalaris seed can lead to unsatisfactory Seed dormancy, thetemporary failure of aviable seed germination in seed testing. The objective was to determine the effec- to germinate (Simpson, 1990), reduces germination per- tiveness of recommended germination methods in overcoming seed dormancy in annual canarygrass (P. canariensis L.). In 2003, 'CDC

M. A. Matus-Cádiz; P. Hucl

2005-01-01

173

Hydrothermal time analysis of seed dormancy in true (botanical) potato seeds  

E-print Network

the hydrothermal time model to analyse the effects of dormancy- breaking treatments on germination of dormant trueHydrothermal time analysis of seed dormancy in true (botanical) potato seeds Veria Alvarado thresholds as dormancy is alleviated. In particular, hydrothermal time analysis of germination sensitivity

Bradford, Kent

174

The Mechanisms Involved in Seed Dormancy Alleviation by Hydrogen Cyanide Unravel the Role of Reactive  

E-print Network

of the ethylene signaling pathway. We propose that ROS play a key role in the control of sunflower seed in the alleviation of embryo dormancy in sunflower seeds. Interestingly, this dormancy breaking effect of cyanideThe Mechanisms Involved in Seed Dormancy Alleviation by Hydrogen Cyanide Unravel the Role

Leubner, Gerhard

175

A simulation model for seasonal changes in dormancy and germination of weed seeds  

Microsoft Academic Search

A model has been developed to simulate the annual dormancy cycle of seeds of light-requiring species in the seed bank and the germination of exhumed seeds after irradiation. Simulation of dormancy and germination is based on a physiological model concerning the action of phytochrome in the seed. Dormancy is related to the amount of a hypothetical phytochrome receptor, which fluctuates

L. M. Vleeshouwers; H. J. Bouwmeester

2001-01-01

176

Physiology of Induction and Relaxation of Summer Dormancy in Perennial Grasses  

Microsoft Academic Search

The involvement of main environmental factors, such as day-length, temperature and water availability, in the imposition and relaxation of the summer dormancy stage in perennial grasses is reviewed. Adaptive value of variation in summer dormancy and differences between summer quiescence and summer dormancy are discussed. The role of high temperature in the inhibition of leaf growth and in the maintenance

J. Kigel; M. Ofir; A. Kon; D. P. Malinowski; W. E. Pinchak

177

Heterogeneity of dormancy in apple embryos. [Pyrus malus  

SciTech Connect

This study concerns the heterogeneity of embryo dormancy with the aim of investigating a possible relationship between chlorophyllogenesis and dormancy. Dormant embryos of Pyrus malus L. cv. Golden delicious were cultivated on water-agar (agar 6 g/l). They were placed flat with one cotyledon in contact with the medium. After 6 days of culture at 23/sup 0/C under fluorescent light the non-germinated embryos (99% of the total) were classified in three main categories on the basis of the state of greening of their cotyledons. By application of partial dormancy releasing treatments (chilling, anaerobiosis, GA/sub 7/), it was shown that the three categories of embryos were characterized by different depths of dormancy. Germination was most difficult for the embryos which were non pigmented after the initial culture, whereas high germination percentages were rapidly reached by embryos exhibiting high degree of greening. Evaluation of ABA by radioimmunoassay shows that the three categories of embryos also differ in their ABA and ABA-GE levels. A good correlation was thus observed between depth of dormancy and levels of ABA and ABA-GE.

Christine, B.; Camille, B.

1986-04-01

178

Breaking seed dormancy of three orthodox Mediterranean Rosaceae species.  

PubMed

Biodiversity levels could be enhanced when regenerating a site by seed-derived seedlings. However, seed dormancy poses limitations for many species. As a result, nurseries either produce seedlings from species where dormancy is not an obstacle, or they propagate through cuttings with the risk of decreasing the genetic diversity within and among species at the regenerated sites. In the present study, breaking of seed dormancy was investigated in valuable Mediterranean species of Prunus avium, Prunus spinosa and Rosa canina Specifically, in order to break dormancy, seeds of those species were warm-, cold-stratified and chemically treated. Based on the results, maximum germination for P. avium was 12% when seeds were warm stratified for four weeks altered with eight weeks of cold stratification. For P. spinosa, maximum percent germination was 26% when seeds were warm stratified for two weeks and continuously altered for eight weeks of cold stratification. Finally, for R. canina maximum percent germination was 40% under four weeks of warm stratification altered with twenty weeks of cold stratification, when seeds were pretreated with H2SO4 for 15 min. A maximum of twelve weeks of cold stratification for P. avium, P. spinosa and 20 weeks for R. canina provided almost zero percent germination. The results indicated that all three species experienced intense dormancy levels suggesting that those species need to be treated properly prior to sowing. Nonetheless, additional experiments are needed to achieve greater germination percentage of highly valuable species in orderto encourage seed derived seedling production. PMID:25895254

Iakovoglou, Valasia; Radoglou, Kalliopi

2015-03-01

179

Informed Consent for PGP Entrance Exam [Version #1  

E-print Network

Informed Consent for PGP Entrance Exam [Version #1] Title: Personal Genome Project Entrance Exam and therefore am providing informed consent for this questionnaire. Name: Email: HMS/HSDM Committee on Human

Church, George M.

180

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

181

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

182

Genetic analysis of two weak dormancy mutants derived from strong seed dormancy wild type rice N22 (Oryza sativa).  

PubMed

Two weak dormancy mutants, designated Q4359 and Q4646, were obtained from the rice cultivar N22 after treatment with 400 Gy (60) Co gamma-radiation. Compared to the N22 cultivar, the dormancy of the mutant seeds was more readily broken when exposed to a period of room temperature storage. The mutants also showed a reduced level of sensitivity to abscisic acid compared to the N22 cultivar, although Q4359 was more insensitive than Q4646. A genetic analysis indicated that in both mutants, the reduced dormancy trait was caused by a single recessive allele of a nuclear gene, but that the mutated locus was different in each case. The results of quantitative trait locus (QTL) mapping, based on the F(2) population from Q4359 x Nanjing35, suggested that Q4359 lacks the QTL?qSdn-1 and carries a novel allele at QTL?qSdn-9, while a similar analysis of the Q4646 x Nanjing35 F(2) population suggested that Q4646 lacks QTL?qSdn-5, both qSdn-1 and?qSdn-5?are major effect seed dormancy QTL in N22. Therefore, these two mutants were helpful to understand the mechanism of seed dormancy in N22. PMID:21418523

Lu, Bingyue; Xie, Kun; Yang, Chunyan; Zhang, Long; Wu, Tao; Liu, Xi; Jiang, Ling; Wan, Jianmin

2011-05-01

183

Studies in seed dormancy : IV. The role of endogenous inhibitors and gibberellin in the dormancy and germination of Corylus avellana L. seeds.  

PubMed

The dormancy of freshly harvested hazel seeds appears to be induced by inhibitors occuring mainly in the testa and pericarp. Although d abscisic acid may not be one of the natural inhibitors involved, d,l abscisic acid has been shown to strongly inhibit the germination of hazel seeds, probably through its antagonism towards the action of gibberellin. Dry storage of hazel nuts causes a deeper state of dormancy (secondary dormancy) to be superimposed on the primary dormancy. It is suggested that secondary dormancy consists of a block to gibberellin synthesis. The essential effect of chilling intact hazel seeds, which is the natural means of breaking their dormancy, may be to activate the mechanism for gibberellin synthesis, the subsequent synthesis of gibberellin being thought to occur at the germination temperature (20°C) and not at the chilling temperature (5°C). PMID:24522735

Bradbeer, J W

1968-09-01

184

Profile of State College Entrance Exam Policies. Maine  

ERIC Educational Resources Information Center

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…

Center on Education Policy, 2011

2011-01-01

185

Profile of State College Entrance Exam Policies. Idaho  

ERIC Educational Resources Information Center

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…

Center on Education Policy, 2011

2011-01-01

186

Profile of State College Entrance Exam Policies. North Dakota  

ERIC Educational Resources Information Center

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…

Center on Education Policy, 2011

2011-01-01

187

Are dormant plants hedging their bets? Demographic consequences of prolonged dormancy in variable environments.  

PubMed

During the growing season, some individuals in perennial plant populations may remain alive belowground while others emerge. This phenomenon, known as prolonged dormancy, seems maladaptive, because prolonged dormancy delays growth and reproduction. However, prolonged dormancy may offer the benefit of safety while belowground, leading to the hypothesis that prolonged dormancy is a bet-hedging strategy. We evaluated this hypothesis using a 25-year demographic study of Astragalus scaphoides, an iteroparous perennial plant. First, we determined the relationship between prolonged dormancy and fitness using data from individuals in our population. This analysis showed that prolonged dormancy decreased arithmetic mean fitness and reduced variance in fitness. Geometric mean fitness was maximized at intermediate levels of prolonged dormancy. Empirical patterns of lifetime reproductive success confirm this relationship. We also compared fitness of plants in our population to hypothetical plants without prolonged dormancy, which generally revealed benefits of prolonged dormancy, even if plants could forgo prolonged dormancy without costs to other vital rates. Therefore, prolonged dormancy may indeed function as a bet-hedging strategy, but the benefits of remaining belowground outweigh the costs only for a subset of individuals. Bet hedging has been demonstrated in plants with simple life histories, such as annuals and monocarpic perennials; we present evidence that bet hedging may be important for plants with more complex life histories. PMID:22322220

Gremer, Jennifer R; Crone, Elizabeth E; Lesica, Peter

2012-03-01

188

Dormancy-associated MADS genes from the EVG locus of peach [Prunus persica (L.) Batsch] have distinct seasonal and photoperiodic expression patterns.  

PubMed

Mapping and sequencing of the non-dormant evg mutant in peach [Prunus persica (L.) Batsch] identified six tandem-arrayed DAM (dormancy-associated MADS-box) genes as candidates for regulating growth cessation and terminal bud formation. To narrow the list of candidate genes, an attempt was made to associate bud phenology with the seasonal and environmental patterns of expression of the candidates in wild-type trees. The expression of the six peach DAM genes at the EVG locus of peach was characterized throughout an annual growing cycle in the field, and under controlled conditions in response to a long day-short day photoperiod transition. DAM1, 2, 4, 5, and 6 were responsive to a reduction in photoperiod in controlled conditions and the direction of response correlated with the seasonal timing of expression in field-grown trees. DAM3 did not respond to photoperiod and may be regulated by chilling temperatures. The DAM genes in peach appear to have at least four distinct patterns of expression. DAM1, 2, and 4 are temporally associated with seasonal elongation cessation and bud formation and are the most likely candidates for control of the evg phenotype. PMID:19553369

Li, Zhigang; Reighard, Gregory Lynn; Abbott, Albert Glenn; Bielenberg, Douglas Gary

2009-01-01

189

Dormancy and quiescence of skeletal muscle stem cells.  

PubMed

The skeletal muscle of vertebrates has a huge regenerative capacity. When destroyed after different types of injury, this organ can regenerate very quickly (less than 20 days following myotoxin injection in the mouse) ad integrum and repeatedly. The cell responsible for this regeneration is the so-called satellite cell, the muscle stem cell that lies on top of the muscle fibre, a giant, multinucleated cell that contains the contractile material. When injected in the muscle, satellite cells can efficiently differentiate into contractile muscle fibres. The satellite cell shows great therapeutic potential; and its regenerative capacity has triggered particular interest in the field of muscular degeneration. In this review we will focus on one particular property of the satellite cell: its quiescence and dormancy. Indeed adult satellite cells are quiescent; they lie between the basal lamina and the basement membrane of the muscle fibre, ready to proliferate, and fuse in order to regenerate myofibers upon injury. It has recently been shown that a subpopulation of satellite cells is able to enter dormancy in human and mice cadavers. Dormancy is defined by a low metabolic state, low mobility, and a long lag before division when plated in vitro, compared to quiescent cells. This definition is also based on current knowledge about long-term hematopoietic stem cells, a subpopulation of stem cells that are described as dormant based on the same criteria (rare division and low metabolism when compared to progeny which are dividing more often). In the first part of this review, we will provide a description of satellite cells which addresses their quiescent state. We will then focus on the uneven distribution of satellite cells in the muscle and describe evidence that suggests that their dormancy differs from one muscle to the next and that one should be cautious when making generalisations regarding this cellular state. In a second part, we will discuss the transition between active dividing cells in developing animals to quiescence. This mechanism could be used or amplified in the switch from quiescence to dormancy. In a third part, we will review the signals and dynamics that actively maintain the satellite cell quiescent. The in-depth understanding of these mechanisms is key to describing how dormancy relies on quiescent state of the cells. In a fourth part, we will deal with dormancy per se: how dormant satellite cells can be obtained, their characteristics, their metabolic profile, and their molecular signature as compared to quiescent cells. Here, we will highlight one of the most important recent findings: that quiescence is a prerequisite for the entry of the satellite cell into dormancy. Since dormancy is a newly discovered phenomenon, we will review the mechanisms responsible for quiescence and activation, as these two cellular states are better known and key to understanding satellite cell dormancy. This will allow us to describe dormancy and its prerequisites. PMID:25344673

Rocheteau, Pierre; Vinet, Mathilde; Chretien, Fabrice

2015-01-01

190

Supercooling in Overwintering Azalea Flower Buds 1  

PubMed Central

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

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

1974-01-01

191

RECENT PROGRESS IN DORMANCY/SPROUT CONTROL RESEARCH  

Technology Transfer Automated Retrieval System (TEKTRAN)

Plant hormones play an essential role in the regulation of potato (Solanum tuberosum L.) tuber dormancy. However, the internal processes that control tuber hormone levels and activities are poorly understood and this ignorance precludes the systematic development of improved methods to control post...

192

Perspectives of biotechnologies based on dormancy phenomenon for space researches  

NASA Astrophysics Data System (ADS)

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

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

193

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...

194

BREAKING SEED DORMANCY IN ECHINACEA ANGUSTIFOLIA AND ARROWLEAF BALSAMROOT  

Microsoft Academic Search

Echinacea angustifolia and arrowleaf ba1samroot are valuable native plants that are difficult to germinate. Three hormones (kinetin, gibberelic acid, and ethylene) were tested along with a potassium nitrate treatment to evaluate their effect on breaking seed dormancy. Germination of E. angustifolia responded very strongly to treatment with ethephon (a source of ethylene), though field emergence was poorer than one would

Peter Sexton

195

Transcriptional Analysis of Dormancy and Sprout Control in Potato  

Technology Transfer Automated Retrieval System (TEKTRAN)

The utility of potato as a major world crop is predicated on its nutritional value as well as its ability to be stored postharvest. Short-term commercial storage of potato tubers may rely on innate tuber dormancy but maintenance of market quality during long-term storage requires the application of ...

196

INVITED REVIEW Plant hormone interactions during seed dormancy release  

E-print Network

- mation and growth of different plant organs. The plant hormones abscisic acid (ABA), gibberellins (GAINVITED REVIEW Plant hormone interactions during seed dormancy release and germination Birgit Kucera1 , Marc Alan Cohn2 and Gerhard Leubner-Metzger1 * 1 Institute of Biology II, Botany/Plant

Leubner, Gerhard

197

Observed limit of Solanum jamesii tuber dormancy at 14 years  

Technology Transfer Automated Retrieval System (TEKTRAN)

Control of tuber dormancy is of interest for commercial potato production and for germplasm preservation in the genebank. We previously reported (AJPR 87:226-228) that tubers of greenhouse-grown Solanum jamesii from 1999 sprouted after 8+ years of storage in a continuous 40F (5C) cooler. One populat...

198

Ethylene, a key factor in the regulation of seed dormancy  

PubMed Central

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 ?L 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

Corbineau, Françoise; Xia, Qiong; Bailly, Christophe

2014-01-01

199

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...

200

Ubiquitin depletion and dominant-negative VPS4 inhibit rhabdovirus budding without affecting alphavirus budding.  

PubMed

The budding reactions of a number of enveloped viruses use the cellular machinery involved in the formation of the luminal vesicles of endosomal multivesicular bodies (MVB). Budding of these viruses is dependent on the presence of specific late-domain motifs in membrane-associated viral proteins. Such budding reactions usually involve ubiquitin and are blocked by expression of an ATPase-deficient form of VPS4, a cellular AAA+ ATPase believed to be required late in the MVB pathway for the disassembly/release of the MVB machinery. Here we examined the role of the MVB pathway in the budding of the late-domain-containing rhabdovirus vesicular stomatitis virus (VSV) and the alphavirus Semliki Forest virus (SFV). We tested early and late steps in the MVB pathway by depleting ubiquitin with the proteasome inhibitor MG-132 and by using cell lines inducibly expressing VPS4A or VPS4B protein. As previously shown, VSV budding was strongly dependent on ubiquitin. In contrast to the findings of previous studies with VPS4A, expression of ATPase-deficient mutants of either VPS4A or VPS4B inhibited VSV budding. Inhibition by VPS4 required the presence of the PPPY late domain on the VSV matrix protein and resulted in the accumulation of nonreleased VSV particles at the plasma membrane. In contrast, SFV budding was independent of both ubiquitin and the activity of VPS4, perhaps reflecting the important role of the highly organized envelope protein lattice during alphavirus budding. PMID:17913808

Taylor, Gwen M; Hanson, Phyllis I; Kielian, Margaret

2007-12-01

201

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

PubMed Central

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

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

2009-01-01

202

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

203

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

204

OBLIQUE PERSPECTIVE OF MAIN ENTRANCE LOOKING NORTHEAST New York ...  

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

OBLIQUE PERSPECTIVE OF MAIN ENTRANCE LOOKING NORTHEAST - New York State Soldiers & Sailors Home, Dining Hall, Department of Veterans Affairs Medical Center, 76 Veterans Avenue, Bath, Steuben County, NY

205

PERSPECTIVE SOUTHWEST OF MAIN ENTRANCE AND NORTH FACADE New ...  

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

PERSPECTIVE SOUTHWEST OF MAIN ENTRANCE AND NORTH FACADE - New York State Soldiers & Sailors Home, Personnel, Department of Veterans Affairs Medical Center, 76 Veterans Avenue, Bath, Steuben County, NY

206

16. ENTRANCE HALL, VIEW OF HALLWAY LOOKING TOWARD STAIR, NOTE ...  

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

16. ENTRANCE HALL, VIEW OF HALLWAY LOOKING TOWARD STAIR, NOTE PEDIMENTED DOORWAYS, CHINESE WALLPAPER, DENTICULATED CORNICE, PANELED DADO - Mt. Harmon Plantation at World's End, Earleville, Cecil County, MD

207

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

208

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

209

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

210

?Cat FACE? SCAR ON LONGLEAF PINE TREE, OVERHILLS HISTORIC ENTRANCE ...  

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

?Cat FACE? SCAR ON LONGLEAF PINE TREE, OVERHILLS HISTORIC ENTRANCE ROAD, FACING NORTHEAST - Overhills, Fort Bragg Military Reservation, Approximately 15 miles NW of Fayetteville, Overhills, Harnett County, NC

211

Virus Budding and the ESCRT Pathway  

PubMed Central

Enveloped viruses escape infected cells by budding through limiting membranes. In the decade since the discovery that the Human Immunodeficiency Virus (HIV) recruits cellular ESCRT (endosomal sorting complexes required for transport) machinery to facilitate viral budding, this pathway has emerged as the major escape route for enveloped viruses. In cells, the ESCRT pathway catalyzes the analogous membrane fission events required for the abscission stage of cytokinesis and for a series of “reverse topology” vesiculation events. Studies of enveloped virus budding are therefore providing insights into the complex cellular mechanisms of cell division and membrane protein trafficking (and vice versa). Here, we review how viruses mimic cellular recruiting signals to usurp the ESCRT pathway, discuss mechanistic models for ESCRT pathway functions, and highlight important research frontiers. PMID:24034610

Votteler, Jörg; Sundquist, Wesley I.

2013-01-01

212

Genetic and environmental control of dormancy in white-grained wheat ( Triticum aestivum L.)  

Microsoft Academic Search

Grain dormancy in wheat is an important component of resistance to preharvest sprouting and hence an important trait for wheat\\u000a breeders. The significant influence of environment on the dormancy phenotype makes this trait an obvious target for marker-assisted-selection.\\u000a Closely related breeding lines, SUN325B and QT7475, containing a major dormancy QTL derived from AUS1408 located on chromosome\\u000a 4A, but substantially different

Daryl Mares; Judith Rathjen; Kolumbina Mrva; Judy Cheong

2009-01-01

213

Variation in dormancy and germination in three co-occurring perennial forest herbs  

Microsoft Academic Search

Mesic deciduous forest herbs often disperse seed with morphophysiological dormancy (MPD) that prevents germination during\\u000a unfavorable periods for seedling survival. However, for seeds of some species with MPD, seasonal separation of root and shoot\\u000a emergence and variation in dormancy levels can complicate interpretation of seedling emergence timing in the field. We tested\\u000a whether dormancy-break and germination requirements differed among co-occurring

Matthew A. Albrecht; Brian C. McCarthy

214

A genetic model and molecular markers for wild oat (Avena fatua L.) seed dormancy  

Microsoft Academic Search

Seed dormancy allows weed seeds to persist in agricultural soils. Wild oat (Avena fatua L.) is a major weed of cereal grains and expresses a range of seed dormancy phenotypes. Genetic analysis of wild oat dormancy\\u000a has been complicated by the difficulty of phenotypic classification in segregating populations. Therefore, little is known\\u000a about the nature of the genes that regulate

S. A. Fennimore; W. E. Nyquist; G. E. Shaner; R. W. Doerge; M. E. Foley

1999-01-01

215

Habitat preferences as related to the prolonged dormancy of perennial herbs and ferns  

Microsoft Academic Search

Prolonged dormancy (hereafter dormancy), a phenomenon in which a perennial herbaceous plant does not sprout for one or more\\u000a years, is examined. The phenomenon may be more frequent than stated so far and discovery of its role in plant life history\\u000a and performance is still underway. Data from published papers was reviewed and all known species exhibiting dormancy were\\u000a analysed

Margit Reintal; Kadri Tali; Marina Haldna; Tiiu Kull

2010-01-01

216

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

PubMed Central

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

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

2013-01-01

217

Interaction between bud-site selection and polarity-establishment machineries in budding yeast  

PubMed Central

Saccharomyces cerevisiae yeast cells polarize in order to form a single bud in each cell cycle. Distinct patterns of bud-site selection are observed in haploid and diploid cells. Genetic approaches have identified the molecular machinery responsible for positioning the bud site: during bud formation, specific locations are marked with immobile landmark proteins. In the next cell cycle, landmarks act through the Ras-family GTPase Rsr1 to promote local activation of the conserved Rho-family GTPase, Cdc42. Additional Cdc42 accumulates by positive feedback, creating a concentrated patch of GTP-Cdc42, which polarizes the cytoskeleton to promote bud emergence. Using time-lapse imaging and mathematical modelling, we examined the process of bud-site establishment. Imaging reveals unexpected effects of the bud-site-selection system on the dynamics of polarity establishment, raising new questions about how that system may operate. We found that polarity factors sometimes accumulate at more than one site among the landmark-specified locations, and we suggest that competition between clusters of polarity factors determines the final location of the Cdc42 cluster. Modelling indicated that temporally constant landmark-localized Rsr1 would weaken or block competition, yielding more than one polarity site. Instead, we suggest that polarity factors recruit Rsr1, effectively sequestering it from other locations and thereby terminating landmark activity. PMID:24062579

Wu, Chi-Fang; Savage, Natasha S.; Lew, Daniel J.

2013-01-01

218

[Further investigations on correlative bud inhibition].  

PubMed

By paper chromatographic analysis with isopropanol-water-ammonia two fractions which inhibit growth and germination and two fractions which promote straight growth but have no effect on germination were isolated from ether extracts of green pea shoots. The four fractions have the following properties:Rf 0.35; acid; promotes Avena straight growth; has no effect on germination of Lepidium;Rf 0.6; acid; inhibits straight growth and germination;Rf 0.75; acid; behaves like fraction Rf 0.35 but is less active;Rf 0.85; neutral or alkaline; acts similarly to fraction Rf 0.6.The activity of the two inhibiting fractions Rf 0.6 and 0.85 in inhibiting Avena straight growth and Lepidium germination is not changed when a neutral solvent (isopropanol-water) is used instead of the alkaline solvent isopropanol-water-ammonia.There is no evidence for an alkaline germination-inhibiting substance with a Rf-value of 0.55, the so-called correlation inhibitor reported by LIBBERT and LIEBENOW (1964).The behavior of the four fractions was investigated especially in two different bud growth tests. 1. Lateral buds from decapitated pea seedlings are prevented from outgrowth by application of lanolin pastes containing the two straight growth and germination inhibitors. The fraction Rf 0.6 is more active in this test than the fraction Rf 0.85. The inhibition is partly cancelled by the simultaneous addition of gibberellic acid. The fractions Rf 0.35 and 0.75 are inactive in this test. 2. In a second bud growth test isolated nodes with a single bud were used. These test organs are placed horizontally with the buds upward into aqueous solutions containing the chromatographic fractions. Bud growth is inhibited by fraction Rf 0.35 and (to a lesser extent) by fraction Rf 0.75; the fractions Rf 0.6 and 0.85 are inactive. The different action of these growth regulators in the described bud growth tests and their possible role in correlative bud inhibition in vivo is discussed. PMID:24557985

Dörffling, K

1966-09-01

219

Maternal environment affects the genetic basis of seed dormancy in Arabidopsis thaliana.  

PubMed

The genetic basis of seed dormancy, a key life history trait important for adaptive evolution in plant populations, has yet been studied only using seeds produced under controlled conditions in greenhouse environments. However, dormancy is strongly affected by maternal environmental conditions, and interactions between seed genotype and maternal environment have been reported. Consequently, the genetic basis of dormancy of seeds produced under natural field conditions remains unclear. We examined the effect of maternal environment on the genetic architecture of seed dormancy using a recombinant inbred line (RIL) population derived from a cross between two locally adapted populations of Arabidopsis thaliana from Italy and Sweden. We mapped quantitative trait loci (QTL) for dormancy of seeds produced in the greenhouse and at the native field sites of the parental genotypes. The Italian genotype produced seeds with stronger dormancy at fruit maturation than did the Swedish genotype in all three environments, and the maternal field environments induced higher dormancy levels compared to the greenhouse environment in both genotypes. Across the three maternal environments, a total of nine dormancy QTL were detected, three of which were only detected among seeds matured in the field, and six of which showed significant QTL × maternal environment interactions. One QTL had a large effect on dormancy across all three environments and colocalized with the candidate gene DOG1. Our results demonstrate the importance of studying the genetic basis of putatively adaptive traits under relevant conditions. PMID:25640699

Postma, Froukje M; Ågren, Jon

2015-02-01

220

Mechanisms of disseminated cancer cell dormancy: an awakening field  

PubMed Central

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

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

2014-01-01

221

Tube entrance heat transfer with deposit formation  

NASA Technical Reports Server (NTRS)

A two-peak wall temperature profile was observed while flowing a kerosene-type gas turbine fuel through a direct-resistance heated tube at an entrance Reynolds number of about 1500. The downstream peak gradually diminished as deposits formed inside the tube, and only one peak remained after seven hours. The observation is explained qualitatively on the basis of analytical and experimental results reported in the literature. It is shown that the temperature profile can be divided into five regions: development of the thermal boundary layer, appearance of the secondary flows, fully developed thermal boundary layer, transition to turbulent flow, and turbulent flow. Deposits increase the tube roughness and reduce the length required for laminar-turbulent transition.

Szetela, E. J.; Sobel, D. R.

1982-01-01

222

Dormancy phases in seeds of Verbascum thapsus L  

Microsoft Academic Search

Summary Seeds ofVerbascum thapsus were imbibed on filter papers in Petri dishes and were exposed to a series of temperatures of 4°C?10°C?20°C?10°C?4°C in darkness. After each temperature treatment lasting one month, samples were removed and tested in light and darkness over a range of alternating temperatures. The results showed us that the dormancy state changes gradually according to the imbibition

Koen A. Vanlerberghe; Jozef A. Van Assche

1986-01-01

223

QTL analysis of seed dormancy in rice ( Oryza sativa L.)  

Microsoft Academic Search

Effective cumulative temperature (ECT) after heading would be a more reasonable parameter for seed sampling of pre-harvest sprouting\\/seed dormancy (SD) tests in segregating populations than the days after flowering. SD is an important agronomic trait associated with grain yielding, eating quality and seed quality. To identify genomic regions affecting SD at different grain-filling temperatures, and to further examine the association

Longbiao Guo; Lihuang Zhu; Yunbi Xu; Dali Zeng; Ping Wu; Qian Qian

2004-01-01

224

Dormancy cues alter insect temperature-size relationships.  

PubMed

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

Clemmensen, Sharon F; Hahn, Daniel A

2015-01-01

225

Concept of common bud and related phenomena in Bryozoa  

E-print Network

THE UNIVERSITY OF KANSAS PALEONTOLOGICAL CONTRIBUTIONS March 1, 1971 Paper 52 CONCEPT OF COMMON BUD AND RELATED PHENOMENA IN BRYOZOA MAXIM K. ELIAS University of Oklahoma, Norman, Oklahoma ABSTRACT The common bud of Stenolaemata (Cyclostomata... of authors), as understood by BORG (1926), is analogous to the buds of higher plants in its terminal position on branches of the Bryozoa and in its vital activities. The common bud is truly common to all developing zooecia in a branch of a zoarium in a sense...

Elias, M. K.

1971-05-01

226

Innervation of Single Fungiform Taste Buds During Development in Rat  

E-print Network

Innervation of Single Fungiform Taste Buds During Development in Rat ROBIN F. KRIMM1 AND DAVID L ganglion cells that innervated single fungiform taste buds were quantified in the tip- and midregions bud, the more geniculate ganglion cells that innervated it. The relationship between ganglion cell

Hill, David L.

227

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

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

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

2008-01-01

228

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

229

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

230

DETAIL OF MAIN ENTRANCE ON NORTH SIDE; NOTE GOTHIC DETAILING ...  

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

DETAIL OF MAIN ENTRANCE ON NORTH SIDE; NOTE GOTHIC DETAILING ON ENTRANCE PAVILION, PARAPET: ORIGINAL, PORTION OF THIS BUILDING WAS DESIGNED BY RATH PLANT ENGINEER J.S. BARTLEY IN 1925 - Rath Packing Company, Administration Building, Sycamore Street between Elm & Eighteenth Streets, Waterloo, Black Hawk County, IA

231

Photo 1. A `Jersey' shoot at the beginning of bud burst. Note the large plump flower  

E-print Network

Photo 1. A `Jersey' shoot at the beginning of bud burst. Note the large plump flower buds located at the ends of last year's growth. The smaller leaf buds, located below the flower buds, are also growing to see flower buds die. At colder temperatures, we will see winter injury to leaf buds and shoots. Woody

Isaacs, Rufus

232

Radiation effects on bovine taste bud membranes  

SciTech Connect

In order to investigate the mechanisms of radiation-induced taste loss, the effects of radiation on preparations of enriched bovine taste bud membranes were studied. Taste buds containing circumvallate papilae, and surrounding control epithelial tissues devoid of taste buds, were obtained from steers and given radiation doses of 0-7000 cGy (rad). Tissue fractions were isolated into membrane-enriched and heterogeneous components using differential and sucrose gradient centrifugation of tissue homogenates. The yield of membranes, as measured by protein content in the buoyant membrane-enriched fractions, was reduced in quantity with increasing radiation dose. The relation between radiation dose and membrane quantity in membrane-enriched fractions could be fit by a simple exponential model with taste bud-derived membranes twice as radiosensitive as membranes from control epithelial tissue. Binding of sucrose, sodium, and acetate and fluoride stimulation of adenylate cyclase were nearly identical in both irradiated and nonirradiated intact membranes. Radiation had no effect on fractions of heterogeneous components. While it is not clear what changes are occurring in enriched taste cell membranes, damage to membranes may play an important role in the taste loss observed in patients following radiotherapy.

Shatzman, A.R.; Mossman, K.L.

1982-11-01

233

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

PubMed Central

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

Ofir, Micha; Kigel, Jaime

2010-01-01

234

Regulation of Summer Dormancy by Water Deficit and ABA in Poa bulbosa Ecotypes  

PubMed Central

Background and Aims Survival of many herbaceous species in Mediterranean habitats during the dry, hot summer depends on the induction of summer dormancy by changes in environmental conditions during the transition between the winter (growth) season to the summer (resting) season, i.e. longer days, increasing temperature and drought. In Poa bulbosa, a perennial geophytic grass, summer dormancy is induced by long days, and the induction is enhanced by high temperature. Here the induction of summer dormancy in a Mediterranean perennial grass by water deficit under non-inductive photoperiodic conditions is reported for the first time. Methods Plants grown under 22/16 °C and non-inductive short-day (9 h, SD) were subjected to water deficit (WD), applied as cycles of reduced irrigation, or sprayed with ABA solutions. They were compared with plants in which dormancy was induced by transfer from SD to inductive long-day (16 h, LD). Responses of two contrasting ecotypes, from arid and mesic habitats were compared. Dormancy relaxation in bulbs from these ecotypes and treatments was studied by comparing sprouting capacity in a wet substrate at 10 °C of freshly harvested bulbs to that of dry-stored bulbs at 40 °C. Endogenous ABA in the bulbs was determined by monoclonal immunoassay analysis. Key Results Dormancy was induced by WD and by ABA application in plants growing under non-inductive SD. Dormancy induction by WD was associated with increased levels of ABA. Bulbs were initially deeply dormant and their sprouting capacity was very low, as in plants in which dormancy was induced by LD. Dormancy was released after 2 months dry storage at 40 °C in all treatments. ABA levels were not affected by dormancy relaxation. Conclusions Summer dormancy in P. bulbosa can be induced by two alternative and probably additive pathways: (1) photoperiodic induction by long-days, and (2) water deficit. Increased levels of endogenous ABA are involved in both pathways. PMID:17202183

Ofir, Micha; Kigel, Jaime

2007-01-01

235

Respiration and hemoglobin function in the giant African bullfrog Pyxicephalus adspersus Tschudi (Anura: Pyxicephalidae) during rest, exercise and dormancy  

Microsoft Academic Search

The survival strategies of frogs exposed to harsh conditions include various forms of dormancy. Giant bullfrogs Pyxicephalus adspersus subjected to slow desiccation without access to moist substrata over winter in cocoons during dormancy. We found that Pyxicephalus can survive long periods of dormancy in soil without forming cocoons. With virtually no information available on the associated respiratory adaptations, we measured

W. J. van Aardt; Roy E. Weber

2010-01-01

236

The role of temperature in the regulation of dormancy and germination of two related summer-annual mudflat species  

Microsoft Academic Search

Dormancy and germination requirements were investigated in seeds (achenes) of the closely-related annuals Bidens cernua and Bidens tripartita (Asteraceae). They showed clear differences in their temperature requirements for germination, their dormancy and seed longevity in soil. In B. cernua seeds, primary dormancy was relieved when stratified at 3, 8, and 12°C, as seeds germinated to a maximum of more than

Markus Brändel

2004-01-01

237

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...

238

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...

239

DEVELOPING WEEDY RICE FOR MAP-BASED CLONING OF SEED DORMANCY GENES.  

Technology Transfer Automated Retrieval System (TEKTRAN)

Seed dormancy in selected O. sativa weedy and cultivated strains and O. glaberrima cultivars was imposed by the seed coverings, i.e., hull and pericarp/testa. Genotypes with a higher level or a much longer duration of seed covering-imposed dormancy were present in weedy rice strains. To investigate ...

240

Genetic Variation of Seed Dormancy in Synthetic Hexaploid Wheat-Derived Populations  

Technology Transfer Automated Retrieval System (TEKTRAN)

Aegilops tauschii, the D-genome donor of wheat (Triticum aestivum), has very strong seed dormancy and genes controlling the trait may be used in breeding programs to manipulate germinability of improved cultivars. Thus, this research was conducted to initiate a project to identify dormancy genes fro...

241

IDENTIFICATION OF QUANTITATIVE TRAIT LOCI (QTLS) FOR DORMANCY IN WILD OAT (AVENA FATUA).  

Technology Transfer Automated Retrieval System (TEKTRAN)

Wild oat is a wide spread weed causing substantial yield losses in small grain crops. Variable germination of seeds due to dormancy makes the control of wild oat difficult. Dormancy is a complex polygenic character with large influences of the environment on its expression. We are investigating gene...

242

ROS production and protein oxidation as a novel mechanism for seed dormancy alleviation  

E-print Network

At harvest, sunflower (Helianthus annuus L.) seeds are dormant and unable to germinate at temperatures below analysis, carbonylation, sunflower. Introduction Seed dormancy, defined as the failure of viable matureROS production and protein oxidation as a novel mechanism for seed dormancy alleviation Krystyna

Leubner, Gerhard

243

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

PubMed

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

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

2014-08-01

244

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...

245

ROS production and protein oxidation as a novel mechanism for seed dormancy alleviation  

Microsoft Academic Search

Summary At harvest, sunflower (Helianthus annuus L.) seeds are dormant and unable to germinate at temperatures below 15? C. Seed storage in the dry state, known as after-ripening, is associated with an alleviation of embryonic dormancy allowing subsequent germination at suboptimal temperatures. To identify the process by which dormancy is broken during after-ripening, we focused on the role of reactive

Krystyna Oracz; Hayat El-Maarouf Bouteau; Jill M. Farrant; Keren Cooper; Maya Belghazi; Claudette Job; Dominique Job; Francoise Corbineau; Christophe Bailly

2007-01-01

246

Identification of seed dormancy for four populations derived from synthetic hexaploid wheat  

Technology Transfer Automated Retrieval System (TEKTRAN)

Seed dormancy is a key adaptive trait for wild species and is also a major domestication-related trait for crop species. Cereal cultivars have been selected for rapid, uniform germination during domestication and breeding and consequently, they generally have an insufficient degree of seed dormancy ...

247

Opposite Effects of Daylength and Temperature on Flowering and Summer Dormancy of Poa bulbosa  

Microsoft Academic Search

? Background and Aims The timing of flowering and summer dormancy induction plays a central role in the adaptation of Mediterranean geophytes to changes in the length of the growth season along rainfall gradients. Our aim was to analyse the role of the variation in the responses of flowering and summer dormancy to vernalization, daylength and growth temperature for the

MICHA O FIR; J AIME K IGEL

248

Opposite Effects of Daylength and Temperature on Flowering and Summer Dormancy of Poa bulbosa  

Microsoft Academic Search

? Background and Aims The timing of flowering and summer dormancy induction plays a central role in the adaptation of Mediterranean geophytes to changes in the length of the growth season along rainfall gradients. Our aim was to analyse the role of the variation in the responses of flowering and summer dormancy to vernalization, daylength and growth temperature for the

MICHA OFIR; JAIME KIGEL

2006-01-01

249

DORMANCY GENES FROM WEEDY RICE RESPOND DIVERGENTLY TO SEED DEVELOPMENT ENVIRONMENTS  

Technology Transfer Automated Retrieval System (TEKTRAN)

Genes interacting with seed developmental environments control primary dormancy. To understand how a multigenic system evolved to adapt to the changing environments in weedy rice, we evaluated genetic components of three dormancy QTLs in a synchronized non-dormant genetic background. Two identical p...

250

Photoperiod Effect on Phytochrome and Abscisic Acid in Alfalfa Varieties Differing in Fall Dormancy  

Microsoft Academic Search

Short daylength (SD) is the main environment-induced factor leading to fall dormancy (FD) in alfalfa (Medicago sativa L.). However, the physiological mechanisms causing varietal differences in shoot growth and fall dormancy of alfalfa crop are not fully understood. The objective of this research was to explore the physiological principles regulating FD in alfalfa by examining phytochrome B (PhyB) and abscisic

Chengzhang Wang; B. L. Ma; Jinfeng Han; Yanhua Wang; Yongge Gao; Xifeng Hu; Chunmei Zhang

2008-01-01

251

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

PubMed

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

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

2015-01-01

252

Environmental regulation of dormancy loss in seeds of Lomatium dissectum (Apiaceae)  

PubMed Central

Background and Aims Lomatium dissectum (Apiaceae) is a perennial, herbaceous plant of wide distribution in Western North America. At the time of dispersal, L. dissectum seeds are dormant and have under-developed embryos. The aims of this work were to determine the requirements for dormancy break and germination, to characterize the type of seed dormancy, and to determine the effect of dehydration after embryo growth on seed viability and secondary dormancy. Methods The temperature requirements for embryo growth and germination were investigated under growth chamber and field conditions. The effect of GA3 on embryo growth was also analysed to determine the specific type of seed dormancy. The effect of dehydration on seed viability and induction of secondary dormancy were tested in seeds where embryos had elongated about 4-fold their initial length. Most experiments examining the nature of seed dormancy were conducted with seeds collected at one site in two different years. To characterize the degree of variation in dormancy-breaking requirements among seed populations, the stratification requirements of seeds collected at eight different sites were compared. Key Results Embryo growth prior to and during germination occurred at temperatures between 3 and 6 °C and was negligible at stratification temperatures of 0·5 and 9·1 °C. Seeds buried in the field and exposed to natural winter conditions showed similar trends. Interruption of the cold stratification period by 8 weeks of dehydration decreased seed viability by about 30 % and induced secondary dormancy in the remaining viable seeds. Comparison of the cold stratification requirements of different seed populations indicates that seeds collected from moist habitats have longer cold stratification requirements that those from semiarid environments. Conclusions Seeds of L. dissectum have deep complex morphophysiological dormancy. The requirements for dormancy break and germination reflect an adaptation to trigger germination in late winter. PMID:19233890

Scholten, Melissa; Donahue, Jacklyn; Shaw, Nancy L.; Serpe, Marcelo D.

2009-01-01

253

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

PubMed Central

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

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

2015-01-01

254

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

PubMed Central

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

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

2014-01-01

255

[What's going on post-budding?].  

PubMed

In general, the retrovirus particles become infectious on post-budding with cleavages of structural protein Gag by viral protease. Protease defective mutants bud particles normally, but the particles are non-infectious and called donuts-like particle because of their morphology. The viral genomes inside the donuts-like particles form very fragile dimer, which are far different from those in wild-type particles. The ordered particle maturation process is essential for infectivity of virus, but its mechanism largely remains unclear. We have constructed HIV-1 Gag cleavage site mutants to enable the steady state observation of virion maturation steps, and precisely study Gag processing, RNA dimerization, virion morphology and infectivity. As results, we found that these process progressed synchronously, but each transition point did not coincide completely. The mutual relationship between viral protein and RNA maturation is discussed for a further understanding of the retroviral life cycle. PMID:21972560

Sakuragi, Jun-ichi

2011-06-01

256

HIV-1 Assembly, Budding, and Maturation  

PubMed Central

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

Sundquist, Wesley I.; Kräusslich, Hans-Georg

2012-01-01

257

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

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

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

2014-09-01

258

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

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

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

2014-01-01

259

Wheat ABA-insensitive mutants result in reduced grain dormancy  

PubMed Central

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 to ABA gradually decreases with dry after-ripening. Scarlet grain normally fails to germinate when fully dormant, shows ABA sensitive germination when partially after-ripened, and becomes ABA insensitive when after-ripened for 8–12 months. Scarlet ABA-insensitive (ScABI) mutants were isolated based on the ability to germinate on 5 µM ABA after only 3 weeks of after-ripening, a condition under which Scarlet would fail to germinate. Six independent seed-specific mutants were recovered. ScABI 1, ScABI2, ScABI3 and ScABI4 are able to germinate more efficiently than Scarlet at up to 25 µM ABA. The two strongest ABA insensitive lines, ScABI3 and ScABI4, both proved to be partly dominant suggesting that they result from gain-of-function mutations. The ScABI1, ScABI2, ScABI3, ScABI4, and ScABI5 mutants after-ripen more rapidly than Scarlet. Thus, ABA insensi-tivity is associated with decreased grain dormancy in Scarlet wheat. This suggests that ABA sensitivity is an important factor controlling grain dormancy in wheat, a trait that impacts seedling emergence and pre-harvest sprouting resistance. PMID:25431501

Schramm, Elizabeth C.; Nelson, Sven K.

2014-01-01

260

The fatty acids of dormant tung buds  

Microsoft Academic Search

Conclusions and Summary  The methyl esters of the fatty acids in the wax of dormant tung buds were prepared and fractionated in a column packed with\\u000a a spiral screen. Myristic, palmitic, linoleic, oleic, and stearic acids were identified in some of the fractions by the saponification\\u000a equivalents and by the melting points of the p-bromophenacyl derivatives of the saturated acids and

Harold M. Sell; Seymour G. Gilbert

1947-01-01

261

Bud3 activates Cdc42 to establish a proper growth site in budding yeast  

PubMed Central

Cell polarization occurs along a single axis that is generally determined by a spatial cue, yet the underlying mechanism is poorly understood. Using biochemical assays and live-cell imaging, we show that cell polarization to a proper growth site requires activation of Cdc42 by Bud3 in haploid budding yeast. Bud3 catalyzes the release of guanosine diphosphate (GDP) from Cdc42 and elevates intracellular Cdc42–guanosine triphosphate (GTP) levels in cells with inactive Cdc24, which has as of yet been the sole GDP–GTP exchange factor for Cdc42. Cdc42 is activated in two temporal steps in the G1 phase: the first depends on Bud3, whereas subsequent activation depends on Cdc24. Mutational analyses suggest that biphasic activation of Cdc42 in G1 is necessary for assembly of a proper bud site. Biphasic activation of Cdc42 or Rac GTPases may be a general mechanism for spatial cue–directed cell polarization in eukaryotes. PMID:25002677

Kang, Pil Jung; Lee, Mid Eum

2014-01-01

262

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

263

South side (red cross office entrance). Fitzsimons General Hospital, ...  

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

South side (red cross office entrance). - Fitzsimons General Hospital, Red Cross Building, South Eighth Street Bounded by West McAfee Avenue on South & West Harlow Avenue on North, Aurora, Adams County, CO

264

12. Cades Cove Road, view toward entrance with ruts in ...  

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

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

265

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

266

Detail of main entrance, camera facing southwest Naval Training ...  

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

Detail of main entrance, camera facing southwest - Naval Training Station, Senior Officers' Quarters District, Quarters No. 1, Naval Station Treasure Island, 1 Whiting Way, Yerba Buena Island, San Francisco, San Francisco County, CA

267

View of two story bay, showing rear entrance, camera facing ...  

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

View of two story bay, showing rear entrance, camera facing northeast - Naval Training Station, Senior Officers' Quarters District, Quarters No. 1, Naval Station Treasure Island, 1 Whiting Way, Yerba Buena Island, San Francisco, San Francisco County, CA

268

Detail of the main entrance and entry porch, camera facing ...  

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

Detail of the main entrance and entry porch, camera facing southwest - Naval Training Station, Senior Officers' Quarters District, Quarters No. 6, Naval Station Treasure Island, 6 Whiting Way, Yerba Buena Island, San Francisco, San Francisco County, CA

269

14. Main entrance to Gwing from Apollo Drive, looking north ...  

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

14. Main entrance to G-wing from Apollo Drive, looking north - Offutt Air Force Base, Strategic Air Command Headquarters & Command Center, Headquarters Building, 901 SAC Boulevard, Bellevue, Sarpy County, NE

270

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

271

PERSPECTIVE LOOKING SOUTH EAST AT ENTRANCE FACADE OF BLDG 92 ...  

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

PERSPECTIVE LOOKING SOUTH EAST AT ENTRANCE FACADE OF BLDG 92 - New York State Soldiers & Sailors Home, Building No. 92, Department of Veterans Affairs Medical Center, 76 Veterans Avenue, Bath, Steuben County, NY

272

PERSPECTIVE LOOKING NORTHEAST SHOWING GARAGE ADDITION AND MODIFIED GARAGE ENTRANCES ...  

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

PERSPECTIVE LOOKING NORTHEAST SHOWING GARAGE ADDITION AND MODIFIED GARAGE ENTRANCES - New York State Soldiers & Sailors Home, Building No. 3, Department of Veterans Affairs Medical Center, 76 Veterans Avenue, Bath, Steuben County, NY

273

PERSPECTIVE LOOKING NORTHWEST SHOWING SOUTH FACADE AND EASTERN ENTRANCE ...  

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

PERSPECTIVE LOOKING NORTHWEST SHOWING SOUTH FACADE AND EASTERN ENTRANCE - New York State Soldiers & Sailors Home, Building No. 9, Department of Veterans Affairs Medical Center, 76 Veterans Avenue, Bath, Steuben County, NY

274

PERSPECTIVE NE FAÇADE. NOTE ADDITIONS AND MODIFICATIONS OF VARIOUS ENTRANCES ...  

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

PERSPECTIVE NE FAÇADE. NOTE ADDITIONS AND MODIFICATIONS OF VARIOUS ENTRANCES FROM ORIGINAL CONSTRUCTION - New York State Soldiers & Sailors Home, Building No. 76, Department of Veterans Affairs Medical Center, 76 Veterans Avenue, Bath, Steuben County, NY

275

PERSPECTIVE LOOKING NE AT SOUTH FAÇADE AND UTILITY ENTRANCES ...  

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

PERSPECTIVE LOOKING NE AT SOUTH FAÇADE AND UTILITY ENTRANCES - New York State Soldiers & Sailors Home, Building No. 76, Department of Veterans Affairs Medical Center, 76 Veterans Avenue, Bath, Steuben County, NY

276

PERSPECTIVE LOOKING NORTH WEST OF ENTRANCE PORCH AND EAST SIDE ...  

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

PERSPECTIVE LOOKING NORTH WEST OF ENTRANCE PORCH AND EAST SIDE OF BUILDING - New York State Soldiers & Sailors Home, Building No. 52, Department of Veterans Affairs Medical Center, 76 Veterans Avenue, Bath, Steuben County, NY

277

PERSPECTIVE LOOKING WEST OF EASTERN ENTRANCE FACADE New York ...  

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

PERSPECTIVE LOOKING WEST OF EASTERN ENTRANCE FACADE - New York State Soldiers & Sailors Home, Police and Voluntary Service, Department of Veterans Affairs Medical Center, 76 Veterans Avenue, Bath, Steuben County, NY

278

PERSPECTIVE OF SOUTH PORCH ENTRANCE AND EAST SIDE OF BUILDING ...  

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

PERSPECTIVE OF SOUTH PORCH ENTRANCE AND EAST SIDE OF BUILDING - New York State Soldiers & Sailors Home, Building No. 33, Department of Veterans Affairs Medical Center, 76 Veterans Avenue, Bath, Steuben County, NY

279

PERSPECTIVE VIEW OF QUARTERS 50 ALONG EAST ENTRANCE ROAD LOOKING ...  

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

PERSPECTIVE VIEW OF QUARTERS 50 ALONG EAST ENTRANCE ROAD LOOKING EAST - New York State Soldiers & Sailors Home, Residential Quarters, Department of Veterans Affairs Medical Center, 76 Veterans Avenue, Bath, Steuben County, NY

280

Perspective view of main entrance, north façade with two story ...  

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

Perspective view of main entrance, north façade with two story square tower, Note medical cross made of wood on tower, originally there were four. - Richmond Field Hospital, 1330 Cutting Boulevard, Richmond, Contra Costa County, CA

281

PERSPECTIVE VIEW QUARTERS 54 SHOWING PORCH AND MAIN ENTRANCE ...  

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

PERSPECTIVE VIEW QUARTERS 54 SHOWING PORCH AND MAIN ENTRANCE - New York State Soldiers & Sailors Home, Residential Quarters, Department of Veterans Affairs Medical Center, 76 Veterans Avenue, Bath, Steuben County, NY

282

17. DETAILED VIEW OF THE ENTRANCE OF THE COTTON WOOD ...  

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

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

283

1. Entrance to Heintooga Round Bottom Road and sign looking ...  

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

1. Entrance to Heintooga Round Bottom Road and sign looking N. - Great Smoky Mountains National Park Roads & Bridges, Heintooga Round Bottom Road & Balsam Mountain Road, Between Blue Ridge Parkway & Big Cove Road, Gatlinburg, Sevier County, TN

284

1. LYLENEWMAN HOUSES (in center, with stoops and side entrances). ...  

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

1. LYLE-NEWMAN HOUSES (in center, with stoops and side entrances). Photocopy of December 1957 photo on file at Philadelphia Historical Commission - Lyle-Newman Houses, 905-907 South Front Street, Philadelphia, Philadelphia County, PA

285

1. GENERAL VIEW OF SOUTH SIDE ELEVATION FROM ENTRANCE GATE, ...  

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

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

286

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

287

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

288

1. BUILDING 324, SOUTH SIDE, FROM F STREET OPPOSITE ENTRANCE, ...  

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

1. BUILDING 324, SOUTH SIDE, FROM F STREET OPPOSITE ENTRANCE, LOOKING NORTH. - Oakland Naval Supply Center, Commanding Officers Residences, Between E & F Streets, West of Fourth Street, Oakland, Alameda County, CA

289

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

290

72. SECOND FLOOR, HEATER ROOM ENTRANCE (UPPER RIGHT) AND STEEL, ...  

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

72. SECOND FLOOR, HEATER ROOM ENTRANCE (UPPER RIGHT) AND STEEL, CONCRETE, BRICK, AND SPRING AIR CONDITIONER BASE, BAY 31-32/4 SOUTH, TO WEST - Ford Motor Company Edgewater Assembly Plant, Assembly Building, 309 River Road, Edgewater, Bergen County, NJ

291

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

292

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

293

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

294

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

295

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

296

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

297

50. POWDER MAGAZINE, VIEW THROUGH DOORWAY ENTRANCE FROM NORTHEAST TO ...  

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

50. POWDER MAGAZINE, VIEW THROUGH DOORWAY ENTRANCE FROM NORTHEAST TO SOUTHWEST REAR. NOTE RUBBLE STONE WALL IN AIR VENTILATION PASSAGE THROUGH ACCESS IN REAR OF MAGAZINE. - Fort Monroe, Fortress, Hampton, Hampton, VA

298

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

299

View looking West into East entrance of New York State ...  

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

View looking West into East entrance of New York State Soldiers &Sailors Home complex - New York State Soldiers & Sailors Home, Department of Veterans Affairs Medical Center, 76 Veterans Avenue, Bath, Steuben County, NY

300

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

301

8. LOOKING SOUTHWEST, SHOWING DETAIL OF PORCHED ENTRANCE TO STORAGE ...  

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

8. LOOKING SOUTHWEST, SHOWING DETAIL OF PORCHED ENTRANCE TO STORAGE AREA, AND NORTHEAST CORNER OF DINING ROOM IN BACKGROUND - Camp Cleawox Organizational Tract, Lodge Building, Oregon Dunes National Recreation Area, Siuslaw National Forest, Florence, Lane County, OR

302

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

303

3. Perspective view of west entrance to Gas House. ...  

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

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

304

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

305

INTERIOR TOWER ENTRANCE, LOOKING NORTH. Oregon Inlet Coast Guard ...  

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

INTERIOR TOWER ENTRANCE, LOOKING NORTH. - Oregon Inlet Coast Guard Station, Northern end of Pea Island, East side of State Road 1257, 0.3 mile North of North Carolina Highway 12, Rodanthe, Dare County, NC

306

14. Inner double blast door entrance to perimeter acquisition radar ...  

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

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

307

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

308

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

309

Wil Wheaton and the Grand Entrance - Duration: 4:07.  

NASA Video Gallery

As NASA prepares for Curiosity rover landing on Mars, Wil Wheaton shares this thrilling story of NASA's hardest planetary science mission to date. The video titled, "Grand Entrance," guides viewers...

310

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

311

15. ROOMS 48 AND 49, LOOKING SOUTH FROM ENTRANCE TO ...  

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

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

312

1. Roaring Fork Motor Nature Trail, entrance sign. Great ...  

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

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

313

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

314

6. MAIN ENTRANCE, LOOKING SOUTH FROM SYCAMORE STREET; CORNER OF ...  

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

6. MAIN ENTRANCE, LOOKING SOUTH FROM SYCAMORE STREET; CORNER OF BUILDING 88 IS VISIBLE AT RIGHT, BUILDING 93 IS AT CENTER, BUILDING 145 AT LEFT - Rath Packing Company, Sycamore Street between Elm & Eighteenth Streets, Waterloo, Black Hawk County, IA

315

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

316

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

317

7. Southwest elevation. Detail of main entrance showing three arched ...  

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

7. Southwest elevation. Detail of main entrance showing three arched doorways and engraved scroll sign. - Union Township School, East side of State Route 4033, North of State Route 4037, Ringtown, Schuylkill County, PA

318

Imaging Spectrometer Designs Utilizing Immersed Gratings With Accessible Entrance Slit  

DOEpatents

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.

Chrisp, Michael P. (Danville, CA); Lerner, Scott A. (Corvallis, OR)

2006-03-21

319

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

320

Phenotypic Selection for Dormancy Introduced a Set of Adaptive Haplotypes From Weedy Into Cultivated Rice  

PubMed Central

Association of seed dormancy with shattering, awn, and black hull and red pericarp colors enhances survival of wild and weedy species, but challenges the use of dormancy genes in breeding varieties resistant to preharvest sprouting. A phenotypic selection and recurrent backcrossing technique was used to introduce dormancy genes from a wild-like weedy rice to a breeding line to determine their effects and linkage with the other traits. Five generations of phenotypic selection alone for low germination extremes simultaneously retained dormancy alleles at five independent QTL, including qSD12 (R2 > 50%), as determined by genome-wide scanning for their main and/or epistatic effects in two BC4F2 populations. Four dormancy loci with moderate to small effects colocated with QTL/genes for one to three of the associated traits. Multilocus response to the selection suggests that these dormancy genes are cumulative in effect, as well as networked by epistases, and that the network may have played a “sheltering” role in maintaining intact adaptive haplotypes during the evolution of weeds. Tight linkage may prevent the dormancy genes from being used in breeding programs. The major effect of qSD12 makes it an ideal target for map-based cloning and the best candidate for imparting resistance to preharvest sprouting. PMID:15972459

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

2005-01-01

321

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

PubMed

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

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

2015-06-01

322

A Cellular Automaton Model for Tumor Dormancy: Emergence of a Proliferative Switch  

PubMed Central

Malignant cancers that lead to fatal outcomes for patients may remain dormant for very long periods of time. Although individual mechanisms such as cellular dormancy, angiogenic dormancy and immunosurveillance have been proposed, a comprehensive understanding of cancer dormancy and the “switch” from a dormant to a proliferative state still needs to be strengthened from both a basic and clinical point of view. Computational modeling enables one to explore a variety of scenarios for possible but realistic microscopic dormancy mechanisms and their predicted outcomes. The aim of this paper is to devise such a predictive computational model of dormancy with an emergent “switch” behavior. Specifically, we generalize a previous cellular automaton (CA) model for proliferative growth of solid tumor that now incorporates a variety of cell-level tumor-host interactions and different mechanisms for tumor dormancy, for example the effects of the immune system. Our new CA rules induce a natural “competition” between the tumor and tumor suppression factors in the microenvironment. This competition either results in a “stalemate” for a period of time in which the tumor either eventually wins (spontaneously emerges) or is eradicated; or it leads to a situation in which the tumor is eradicated before such a “stalemate” could ever develop. We also predict that if the number of actively dividing cells within the proliferative rim of the tumor reaches a critical, yet low level, the dormant tumor has a high probability to resume rapid growth. Our findings may shed light on the fundamental understanding of cancer dormancy. PMID:25329892

Chen, Duyu; Jiao, Yang; Torquato, Salvatore

2014-01-01

323

Mapping of QTL for seed dormancy in a winter oilseed rape doubled haploid population.  

PubMed

Following winter oilseed rape cultivation, considerable numbers of volunteer oilseed rape plants may occur in subsequent years in following crops. The appearance of volunteer oilseed rape plants is based on the capability of the seeds to become secondary dormant and to survive in this stage for many years in the soil. Genetic reduction of secondary seed dormancy in oilseed rape could provide a means to reduce the frequency of volunteer plants and especially the dispersal of transgenic oilseed rape. The objective of the present study was to analyse the inheritance of primary and secondary seed dormancy in a winter oilseed rape doubled haploid population derived from the cross Express 617 × R53 and to study correlations to other seed traits. Field experiments were performed in Germany for 2 years at two locations with two replicates. Seeds harvested from open pollinated plants were used for all analyses, including a laboratory test for seed dormancy. A previously developed molecular marker map of the doubled haploid population was used to map QTL of the relevant traits. For primary, secondary and total seed dormancy, the results showed significant effects of the genotypes and their interactions, with years and locations. Two, four and five QTL were detected for primary, secondary and total seed dormancy which explained 19, 35 and 42 % of the phenotypic variance, respectively. Results show that secondary seed dormancy is a heritable trait and that selection for low secondary seed dormancy is possible. PMID:23783224

Schatzki, Jörg; Schoo, Burkhard; Ecke, Wolfgang; Herrfurth, Cornelia; Feussner, Ivo; Becker, Heiko C; Möllers, Christian

2013-09-01

324

Dormancy Is Not Necessary or Sufficient for Bacterial Persistence  

PubMed Central

The antibiotic tolerances of bacterial persisters have been attributed to transient dormancy. While persisters have been observed to be growth inhibited prior to antibiotic exposure, we sought to determine whether such a trait was essential to the phenotype. Furthermore, we sought to provide direct experimental evidence of the persister metabolic state so as to determine whether the common assumption of metabolic inactivity was valid. Using fluorescence-activated cell sorting (FACS), a fluorescent indicator of cell division, a fluorescent measure of metabolic activity, and persistence assays, we found that bacteria that are rapidly growing prior to antibiotic exposure can give rise to persisters and that a lack of replication or low metabolic activity prior to antibiotic treatment simply increases the likelihood that a cell is a persister. Interestingly, a lack of significant growth or metabolic activity does not guarantee persistence, as the majority of even “dormant” subpopulations (>99%) were not persisters. These data suggest that persistence is far more complex than dormancy and point to additional characteristics needed to define the persister phenotype. PMID:23629720

Orman, Mehmet A.

2013-01-01

325

Estimation of population effects in synchronized budding yeast experiments  

NASA Astrophysics Data System (ADS)

An approach for estimating the distribution of a synchronized budding yeast (Saccharomyces cerevisiae) cell population is discussed. This involves estimation of the phase of the cell cycle for each cell. The approach is based on counting the number of buds of different sizes in budding yeast images. An image processing procedure is presented for the bud-counting task. The procedure employs clustering of the local mean-variance space for segmentation of the images. The subsequent bud-detection step is based on an object separation method which utilizes the chain code representation of objects as well as labeling of connected components. The procedure is tested with microscopic images that were obtained in a time-series experiment of a synchronized budding yeast cell population. The use of the distribution estimate of the cell population for inverse filtering of signals that are obtained in time-series microarray measurements is discussed as well.

Niemistoe, Antti; Aho, Tommi; Thesleff, Henna; Tiainen, Mikko; Marjanen, Kalle; Linne, Marja-Leena; Yli-Harja, Olli P.

2003-05-01

326

Opposite Effects of Daylength and Temperature on Flowering and Summer Dormancy of Poa bulbosa  

PubMed Central

• Background and Aims The timing of flowering and summer dormancy induction plays a central role in the adaptation of Mediterranean geophytes to changes in the length of the growth season along rainfall gradients. Our aim was to analyse the role of the variation in the responses of flowering and summer dormancy to vernalization, daylength and growth temperature for the adaptation of Poa bulbosa, a perennial geophytic grass, to increasing aridity. • Methods Flowering and dormancy were studied under controlled daylengths [9?h short day (SD) vs. 16?h long day (LD)] and temperatures (16/10, 22/16 and 28/22?°C day/night) in four ecotypes originating in arid, semi-arid and mesic habitats (110, 276 and 810?mm rain year?1, respectively) and differing in flowering capacity under natural conditions: arid–flowering, semi-arid–flowering, semi-arid–non-flowering and mesic–non-flowering. • Key Results Flowering and dormancy were affected in opposite ways by daylength and growth temperature. Flowering occurred almost exclusively under SD. In contrast, plants became dormant much earlier under LD than under SD. In both daylengths, high temperature and pre-chilling (6 weeks at 5?°C) enhanced dormancy imposition, but inhibited or postponed flowering, respectively. Induction of flowering and dormancy in the different ecotypes showed differential responsiveness to daylength and temperature. Arid and semi-arid ecotypes had a higher proportion of flowering plants and flowering tillers as well as more panicles per plant than mesic ecotypes. ‘Flowering’ ecotypes entered dormancy earlier than ‘non-flowering’ ecotypes, while the more arid the site of ecotype origin, the earlier the ecotype entered dormancy. • Conclusions Variation in the flowering capacity of ecotypes differing in drought tolerance was interpreted as the result of balanced opposite effects of daylength and temperature on the flowering and dormancy processes. PMID:16467351

OFIR, MICHA; KIGEL, JAIME

2006-01-01

327

Bud and Yvonne, still imageSite: DNA Interactive (www.dnai.org)  

NSDL National Science Digital Library

Bud and Yvonne are delighted by Bud's recovery thanks to Gleevec. Diagnosed with chronic myeloid leukemia (CML), Bud noticed an article in the newspaper on Brian Druker's research. Bud and his wife Yvonne contacted Druker in 1996, and Bud was the first patient to receive the drug STI-571 (Gleevec) in clinical trials.

2008-10-06

328

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

PubMed

The yeast KEOPS protein complex comprising Kae1, Bud32, Cgi121, Pcc1 and Gon7 is responsible for the essential tRNA threonylcarbamoyladenosine (t(6)A) 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

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

2015-03-31

329

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

PubMed Central

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

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

2015-01-01

330

Overexpression of CONSTANS homologs CO1 and CO2 fails to alter normal reproductive onset and fall bud set in woody perennial poplar.  

PubMed

CONSTANS (CO) is an important flowering-time gene in the photoperiodic flowering pathway of annual Arabidopsis thaliana in which overexpression of CO induces early flowering, whereas mutations in CO cause delayed flowering. The closest homologs of CO in woody perennial poplar (Populus spp.) are CO1 and CO2. A previous report showed that the CO2/FLOWERING LOCUS T1 (FT1) regulon controls the onset of reproduction in poplar, similar to what is seen with the CO/FLOWERING LOCUS T (FT) regulon in Arabidopsis. The CO2/FT1 regulon was also reported to control fall bud set. Our long-term field observations show that overexpression of CO1 and CO2 individually or together did not alter normal reproductive onset, spring bud break, or fall dormancy in poplar, but did result in smaller trees when compared with controls. Transcripts of CO1 and CO2 were normally most abundant in the growing season and rhythmic within a day, peaking at dawn. Our manipulative experiments did not provide evidence for transcriptional regulation being affected by photoperiod, light intensity, temperature, or water stress when transcripts of CO1 and CO2 were consistently measured in the morning. A genetic network analysis using overexpressing trees, microarrays, and computation demonstrated that a majority of functionally known genes downstream of CO1 and CO2 are associated with metabolic processes, which could explain their effect on tree size. In conclusion, the function of CO1 and CO2 in poplar does not appear to overlap with that of CO from Arabidopsis, nor do our data support the involvement of CO1 and CO2 in spring bud break or fall bud set. PMID:23029015

Hsu, Chuan-Yu; Adams, Joshua P; No, Kyoungok; Liang, Haiying; Meilan, Richard; Pechanova, Olga; Barakat, Abdelali; Carlson, John E; Page, Grier P; Yuceer, Cetin

2012-01-01

331

The Bud14p–Glc7p complex functions as a cortical regulator of dynein in budding yeast  

Microsoft Academic Search

Regulated interactions between microtubules (MTs) and the cell cortex control MT dynamics and position the mitotic spindle. In eukaryotic cells, the adenomatous polyposis coli\\/Kar9p and dynein\\/dynactin pathways are involved in guiding MT plus ends and MT sliding along the cortex, respectively. Here we identify Bud14p as a novel cortical activator of the dynein\\/dynactin complex in bud- ding yeast. Bud14p accumulates

Michèle Knaus; Elisabetta Cameroni; Ivo Pedruzzi; Kelly Tatchell; Claudio De Virgilio; Matthias Peter

2005-01-01

332

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

PubMed

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

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

2013-09-17

333

Essential Oil of Betula pendula Roth. Buds  

PubMed Central

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 ?-copaene (12% and 10%), germacrene D (11% and 18%) and ?-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

2004-01-01

334

Cell Polarization and Cytokinesis in Budding Yeast  

PubMed Central

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

Bi, Erfei; Park, Hay-Oak

2012-01-01

335

Germination responses to temperature and water potential in Jatropha curcas seeds: a hydrotime model explains the difference between dormancy expression and dormancy induction at different incubation temperatures  

PubMed Central

Background and Aims Jatropha curcas is a drought-resistant tree whose seeds are a good source of oil that can be used for producing biodiesel. A successful crop establishment depends on a rapid and uniform germination of the seed. In this work we aimed to characterize the responses of J. curcas seeds to temperature and water availability, using thermal time and hydrotime analysis, Methods Thermal and hydrotime analysis was performed on germination data obtained from the incubation of seeds at different temperatures and at different water potentials. Key Results Base and optimum temperatures were 14·4 and 30 °C, respectively. Approximately 20 % of the seed population displayed absolute dormancy and part of it displayed relative dormancy which was progressively expressed in further fractions when incubation temperatures departed from 25 °C. The thermal time model, but not the hydrotime model, failed to describe adequately final germination percentages at temperatures other than 25 °C. The hydrotime constant, ?H, was reduced when the incubation temperature was increased up to 30 °C, the base water potential for 50 % germination,?b(50), was less negative at 20 and 30 °C than at 25 °C, indicating either expression or induction of dormancy. At 20 °C this less negative ?b(50) explained satisfactorily the germination curves obtained at all water potentials, while at 30 °C it had to be corrected towards even less negative values to match observed curves at water potentials below 0. Hence, ?b(50) appeared to have been further displaced to less negative values as exposure to 30 °C was prolonged by osmoticum. These results suggest expression of dormancy at 20 °C and induction of secondary dormancy above 25 °C. This was confirmed by an experiment showing that inhibition of germination imposed by temperatures higher than 30 °C, but not that imposed at 20 °C, is a permanent effect. Conclusions This study revealed (a) the extremely narrow thermal range within which dormancy problems (either through expression or induction of dormancy) may not be encountered; and (b) the high sensitivity displayed by these seeds to water shortage. In addition, this work is the first one in which temperature effects on dormancy expression could be discriminated from those on dormancy induction using a hydrotime analysis. PMID:21917817

Windauer, Liliana B.; Martinez, J.; Rapoport, D.; Wassner, D.; Benech-Arnold, Roberto

2012-01-01

336

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

SciTech Connect

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.

Kitchen, S.G.; Meyer, S.E. (Dept of Agriculture, Provo, UT (United States))

1992-03-01

337

Molecular Mechanism of Arenavirus Assembly and Budding  

PubMed Central

Arenaviruses have a bisegmented negative-strand RNA genome, which encodes four viral proteins: GP and NP by the S segment and L and Z by the L segment. These four viral proteins possess multiple functions in infection, replication and release of progeny viruses from infected cells. The small RING finger protein, Z protein is a matrix protein that plays a central role in viral assembly and budding. Although all arenaviruses encode Z protein, amino acid sequence alignment showed a huge variety among the species, especially at the C-terminus where the L-domain is located. Recent publications have demonstrated the interactions between viral protein and viral protein, and viral protein and host cellular protein, which facilitate transportation and assembly of viral components to sites of virus egress. This review presents a summary of current knowledge regarding arenavirus assembly and budding, in comparison with other enveloped viruses. We also refer to the restriction of arenavirus production by the antiviral cellular factor, Tetherin/BST-2. PMID:23202453

Urata, Shuzo; Yasuda, Jiro

2012-01-01

338

Electrochemical Regulation of Budding Yeast Polarity  

PubMed Central

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

Piel, Matthieu; Chang, Fred; Minc, Nicolas

2014-01-01

339

Stochastic exit from mitosis in budding yeast  

PubMed Central

Unlike many mutants that are completely viable or inviable, the CLB2-db? clb5? mutant of Saccharomyces cerevisiae is inviable in glucose but partially viable on slower growth media such as raffinose. On raffinose, the mutant cells can bud and divide but in each cycle there is a chance that a cell will fail to divide (telophase arrest), causing it to exit the cell cycle. This effect gives rise to a stochastic phenotype that cannot be explained by a deterministic model. We measure the interbud times of wild-type and mutant cells growing on raffinose and compute statistics and distributions to characterize the mutant's behavior. We convert a detailed deterministic model of the budding yeast cell cycle to a stochastic model and determine the extent to which it captures the stochastic phenotype of the mutant strain. Predictions of the mathematical model are in reasonable agreement with our experimental data and suggest directions for improving the model. Ultimately, the ability to accurately model stochastic phenotypes may prove critical to understanding disease and therapeutic interventions in higher eukaryotes. PMID:21350333

Ball, David A; Ahn, Tae-Hyuk; Wang, Pengyuan; Chen, Katherine C; Cao, Yang; Tyson, John J; Peccoud, Jean

2011-01-01

340

Dormancy patterns, germination ecology, and seed-bank types of twenty temperate fen grassland species  

Microsoft Academic Search

The germination ecology, including primary and secondary dormancy, mortality of seeds, and seed-bank type, of 20 fen grassland\\u000a species from Northern Germany was investigated using a combination of burial and germination experiments. To analyze primary\\u000a dormancy and effects of after-ripening (dry storage for 28 days) on freshly matured seeds, germination was measured at two\\u000a fluctuating temperature regimes (15\\/25°C and 5\\/15°C)

Kai Jensen

2004-01-01

341

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

PubMed Central

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

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

2013-01-01

342

Identification of genomic regions associated with seed dormancy in white-grained wheat  

Microsoft Academic Search

Pre-harvest sprouting (PHS) in developing wheat (Triticum aestivum L.) spikes is stimulated by cool and wet weather and leads to a decline in grain quality. A low level of harvest-time seed\\u000a dormancy is a major factor for PHS, which generally is a larger problem in white-grained as compared to red-grained wheat.\\u000a We have in this study analyzed seed dormancy levels

Rajender Singh; Maria Matus-Cádiz; Monica Båga; Pierre Hucl; Ravindra N. Chibbar

2010-01-01

343

Prognostic value of tumor “budding” in patients with colorectal cancer  

Microsoft Academic Search

From 1970 to 1985, 663 patients underwent curative resection of colon and rectal adenocarcinomas. All surgical specimens were examined for tumor “budding,” defined as small clusters of undifferentiated cancer cells ahead of the invasive front of the lesion. Patients were divided into two groups according to degree of budding: none or mild (BD-1) and moderate or severe (BD-2). BD-1 occurred

Kazuo Hase; Clayton Shatney; Denise Johnson; Michael Trollope; Mark Vierra

1993-01-01

344

Encapsulation of micropropagated buds of six woody species  

Microsoft Academic Search

Regrowth after encapsulation in a sodium alginate matrix of micropropagated buds from six different in vitro proliferated woody species was evaluated. Actinidia deliciosa Liang & Ferguson (kiwifruit), Betula pendula Roth (birch), Crataegus oxyacantha L. (hawthorn), Malus spp. (apple), Rubus spp. (blackberry) and Rubus idaeus L. (raspberry) propagated in vitro were used as bud sources. Encapsulation with sodium alginate and subsequent

Emanuele Piccioni; Alvaro Standardi

1995-01-01

345

Control of bud activation by an auxin transport switch  

E-print Network

Control of bud activation by an auxin transport switch Przemyslaw Prusinkiewicza,1 , Scott buds. This process is termed apical dominance and is dependent on the plant hormone auxin moving down the main stem in the polar auxin transport stream. We use a computational model and math- ematical analysis

Prusinkiewicz, Przemyslaw

346

Stimulation of Bud Production in Eucalyptus globulus by Paclobutrazol Application  

Microsoft Academic Search

Trunk injection of paclobutrazol (Clipper) significantly increased the bud crop on 7-year-old Eucalyptus globulus (Labill.) seed orchard trees, within one year of application. This is the first reported stimulation of reproduction to occur, with eucalypts, in the season of application. Ethephon (Ethrel), daminozide (Alar) and daminozide combined with ethephon, had no significant effect on bud production. Paclobutrazol combined with ethephon

S. Hetherington; K. M. Jones; T. B. Koen

1992-01-01

347

Photocontrol of bud burst involves gibberellin biosynthesis in Rosa sp.  

PubMed

Light is a critical determinant of plant shape by controlling branching patterns and bud burst in many species. To gain insight into how light induces bud burst, we investigated whether its inductive effect in rose was related to gibberellin (GA) biosynthesis. In axillary buds of beheaded plants subject to light, the expression of two GA biosynthesis genes (RoGA20ox and RoGA3ox) was promptly and strongly induced, while that of a GA-catabolism genes (RoGA2ox) was reduced. By contrast, lower expression levels of these two GA biosynthesis genes were found in darkness, and correlated with a total inhibition of bud burst. This effect was dependent on both light intensity and quality. In in vitro cultured buds, the inductive effect of light on the growth of preformed leaves and SAM organogenic activity was inhibited by ancymidol and paclobutrazol, two effectors of GA biosynthesis. This effect was concentration-dependent, and negated by GA(3). However, GA(3) alone could not rescue bud burst in the dark. GA biosynthesis was also required for the expression and activity of a vacuolar invertase, and therefore for light-induced sugar metabolism within buds. These findings are evidence that GA biosynthesis contributes to the light effect on bud burst and lay the foundations of a better understanding of its exact role in plant branching. PMID:22749285

Choubane, Djillali; Rabot, Amélie; Mortreau, Eric; Legourrierec, Jose; Péron, Thomas; Foucher, Fabrice; Ahcène, Youyou; Pelleschi-Travier, Sandrine; Leduc, Nathalie; Hamama, Latifa; Sakr, Soulaiman

2012-09-01

348

Cytokinin effect on branching and bud formation in Funaria.  

PubMed

Cytokinins have two different effects on protonemata of Funaria hygrometrica. They induce branching of unbranched caulonemata and bud formation. Branching occurs after treatment with pico-molar concentrations of cytokinins whereas bud formation requires micro-molar concentrations. Both processes are therefore independently stimulated by cytokinins. PMID:24232661

Bopp, M; Jacob, H J

1986-11-01

349

RNA-Seq transcriptome analysis of Spirodela dormancy without reproduction  

PubMed Central

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

2014-01-01

350

An Experimental Investigation of NACA Submerged-Duct Entrances  

NASA Technical Reports Server (NTRS)

The results of a preliminary investigation of submerged duct entrances are presented. It is shown that an entrance of this type possess desirable critical speed and pressure recovery characteristics when used on a fuselage or nacelle in a region of low incremental velocity and thin boundary layer. The data obtained indicate that submerged entrances are most suitable for use with internal-flow systems which diffuse the air only a small amount: for example, those used with jet motors which have axial-flow compressors. Where complete diffusion of the air is required, fuselage-nose or wing leading edge inlets may prove to be superior. The results of the investigation have been prepared in such a form as to permit their use by a designer and the application of these data to a specific design is discussed.

Frick, Charles W.; Davis, Wallace F.; Randall, Lauros M.; Mossman, Emmet A.

1945-01-01

351

Progressive activation of paratrigeminal nucleus during entrance to hibernation  

SciTech Connect

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.

Kilduff, T.S.; Sharp, F.R.; Heller, H.C. (Stanford Univ., CA (USA) Univ. of California, San Francisco (USA) Veterans Administration Medical Center, San Francisco, CA (USA))

1988-07-01

352

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

PubMed Central

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

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

2003-01-01

353

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

PubMed Central

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

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

2008-01-01

354

The relationship between seed dormancy, seed size and weediness, in Crepis tectorum (Asteraceae).  

PubMed

I examined the germination characteristics of weed and outcrop populations of Crepis tectorum to test the hypothesis that the presumably more ephemeral weed habitat favors the highest levels of seed dormancy. The winter annual habit characterizing most plants of this species was reflected in a rapid germination of seeds sown in late summer. A slightly higher fraction of surface-sown seeds of weed plants delayed germination. Buried seeds of weed plants also survived better than seeds produced by plants in most outcrop populations, supporting the idea that weediness favors seed dormancy and a persistent seed bank. However, the differences in seed dormancy between the two ecotypes were small and not entirely consistent. Furthermore, high levels of seed dormancy were induced during burial in the outcrop group, suggesting that there is a potential for a dormant seed population in this habitat as well. Demographic data from one of the outcrop populations verified the presence of a large between-year seed bank. Possible environmental factors favoring seed dormancy in outcrop populations are discussed. The unusually large seeds of weedy Crepis contrasts with the relatively small difference in seed dormancy between the two ecotypes. PMID:22160124

Anderson, S

1990-06-01

355

Taste buds of the fungiform papillae in Cynomolgus monkey.  

PubMed Central

A study of the number of taste buds borne on 145 fungiform papillae from 20 Cynomolgus monkeys showed that, in contrast to the situation in man, most papillae are bud-bearing. The fine structure of taste buds on fungiform papillae of these monkeys was also examined. The cells contained clear apical vesicles, mitochondria, filament bundles and stacks of Golgi cisternae. Nerve fibres containing mitochondria, as well as clear and dense-cored vesicles, were scattered throughout the whole bud, but were more numerous near the base. It was, however, not possible to distinguish different cell types in these taste buds as a function of cell shape, electron density of the ground cytoplasm, presence of different organelles or relation to nerve processes. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 PMID:6277839

Arvidson, K; Cottler-Fox, M; Friberg, U

1981-01-01

356

An Experimental Investigation of NACA Submerged-Duct Entrances  

NASA Technical Reports Server (NTRS)

The results of an investigation of submerged-duct entrances are presented. It is shown that this type of entrance possesses the following characteristics: 1) very high-critical-compressibility speeds throughout the range of high-speed inlet velocity ratios; 2) very low pressure losses for the air entering the duct at all inlet-velocity ratios; and, 3) low external drag. These characteristics are obtained by the proper shaping of the contour of the upstream approach to the submerged inlets and by proper alignment of the duct lip. Design data are presented and the application of these data to a specific high-speed fighter-airplane design is discussed.

Frick, Charles W.; Davis, Wallace F.; Randall, Lauros; Mossman, Emmet A.

1945-01-01

357

Foyer and entrance details. San Bernardino Valley Union Junior College, ...  

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

Foyer and entrance details. San Bernardino Valley Union Junior College, Auditorium Building. Section through foyer showing ticket window; detail front entrance with tiling; rear of ticket window. G. Stanley Wilson, Architect, A.I.A., Riverside, California. Sheet 13, job no. 692. Scale 3/4 inch to the foot. March 27, 1936. Application no. 1446, approved by the State of California, Department of Public Works, Division of Architecture, April 22, 1936. - San Bernardino Valley College, Auditorium, 701 South Mount Vernon Avenue, San Bernardino, San Bernardino County, CA

358

Fatty acid composition of black bear ( Ursus americanus ) milk during and after the period of winter dormancy  

Microsoft Academic Search

Black bears give birth and lactate during the 2–3-mon fast of winter dormancy. Thereafter the female emerges from the den\\u000a with her cubs and begins to feed. We investigated fatty acid patterns of milk from native Pennsylvania black bears during\\u000a the period of winter dormancy, as well as after den emergence. Throughout winter dormancy, milk fatty acid composition remained\\u000a relatively

Sara J. Iversona; Olav T. Oftedal

1992-01-01

359

High tumor budding stratifies breast cancer with metastatic properties.  

PubMed

Tumor budding refers to single or small cluster of tumor cells detached from the main tumor mass. In colon cancer high tumor budding is associated with positive lymph nodes and worse prognosis. Therefore, we investigated the value of tumor budding as a predictive feature of lymph node status in breast cancer (BC). Whole tissue sections from 148 surgical resection specimens (SRS) and 99 matched preoperative core biopsies (CB) with invasive BC of no special type were analyzed on one slide stained with pan-cytokeratin. In SRS, the total number of intratumoral (ITB) and peripheral tumor buds (PTB) in ten high-power fields (HPF) were counted. A bud was defined as a single tumor cell or a cluster of up to five tumor cells. High tumor budding equated to scores averaging >4 tumor buds across 10HPFs. In CB high tumor budding was defined as ?10 buds/HPF. The results were correlated with pathological parameters. In SRS high PTB stratified BC with lymph node metastases (p ? 0.03) and lymphatic invasion (p ? 0.015). In CB high tumor budding was significantly (p = 0.0063) associated with venous invasion. Pathologists are able, based on morphology, to categorize BC into a high and low risk groups based in part on lymph node status. This risk assessment can be easily performed during routine diagnostics and it is time and cost effective. These results suggest that high PTB is associated with loco-regional metastasis, highlighting the possibility that this tumor feature may help in therapeutic decision-making. PMID:25779101

Salhia, Bodour; Trippel, Mafalda; Pfaltz, Katrin; Cihoric, Nikola; Grogg, André; Lädrach, Claudia; Zlobec, Inti; Tapia, Coya

2015-04-01

360

NAP1 Acts with Clb2 to Perform Mitotic Functions and to Suppress Polar Bud Growth in Budding Yeast  

E-print Network

NAP1 Acts with Clb2 to Perform Mitotic Functions and to Suppress Polar Bud Growth in Budding Yeast, California 94143-0444 Abstract. NAP1 is a 60-kD protein that interacts spe- cificallywith mitotic cyclins in cells that lack NAP1. Our results demonstrate that Clb2 is unable to carry out its full range

Murray, Andrew W.

361

Budding and Fission of a multiphase vesicle  

E-print Network

We present a model of bi-phasic vesicle in the limit of large surface tension. In this regime, the vesicle is completely stretched and well described by two spherical caps with a fold which concentrates the membrane stress. The conservation laws and geometric constraints restrict the space of possible shapes to a pair of solutions labeled by a parameter $\\tau$ given by {\\it line tension/pressure}. For a given $\\tau$ value, the two solutions differ by the length of the interface between domains. For a critical value $\\tau\\_c$, the two vesicle shapes become identical and no solution exists above this critical value. This model sheds new light on two proposed mechanisms (osmotic shocks and molecule absorption) to explain the budding and the fission in recent experiments.

Jean-Marc Allain; Martine Ben Amar

2005-04-08

362

Measuring mitotic spindle dynamics in budding yeast  

NASA Astrophysics Data System (ADS)

In order to carry out its life cycle and produce viable progeny through cell division, a cell must successfully coordinate and execute a number of complex processes with high fidelity, in an environment dominated by thermal noise. One important example of such a process is the assembly and positioning of the mitotic spindle prior to chromosome segregation. The mitotic spindle is a modular structure composed of two spindle pole bodies, separated in space and spanned by filamentous proteins called microtubules, along which the genetic material of the cell is held. The spindle is responsible for alignment and subsequent segregation of chromosomes into two equal parts; proper spindle positioning and timing ensure that genetic material is appropriately divided amongst mother and daughter cells. In this thesis, I describe fluorescence confocal microscopy and automated image analysis algorithms, which I have used to observe and analyze the real space dynamics of the mitotic spindle in budding yeast. The software can locate structures in three spatial dimensions and track their movement in time. By selecting fluorescent proteins which specifically label the spindle poles and cell periphery, mitotic spindle dynamics have been measured in a coordinate system relevant to the cell division. I describe how I have characterised the accuracy and precision of the algorithms by simulating fluorescence data for both spindle poles and the budding yeast cell surface. In this thesis I also describe the construction of a microfluidic apparatus that allows for the measurement of long time-scale dynamics of individual cells and the development of a cell population. The tools developed in this thesis work will facilitate in-depth quantitative analysis of the non-equilibrium processes in living cells.

Plumb, Kemp

363

Molecular characterization of feline immunodeficiency virus budding.  

PubMed

Infection of domestic cats with feline immunodeficiency virus (FIV) is an important model system for studying human immunodeficiency virus type 1 (HIV-1) infection due to numerous similarities in pathogenesis induced by these two lentiviruses. However, many molecular aspects of FIV replication remain poorly understood. It is well established that retroviruses use short peptide motifs in Gag, known as late domains, to usurp cellular endosomal sorting machinery and promote virus release from infected cells. For example, the Pro-Thr/Ser-Ala-Pro [P(T/S)AP] motif of HIV-1 Gag interacts directly with Tsg101, a component of the endosomal sorting complex required for transport I (ESCRT-I). A Tyr-Pro-Asp-Leu (YPDL) motif in equine infectious anemia virus (EIAV), and a related sequence in HIV-1, bind the endosomal sorting factor Alix. In this study we sought to identify and characterize FIV late domain(s) and elucidate cellular machinery involved in FIV release. We determined that mutagenesis of a PSAP motif in FIV Gag, small interfering RNA-mediated knockdown of Tsg101 expression, and overexpression of a P(T/S)AP-binding fragment of Tsg101 (TSG-5') each inhibited FIV release. We also observed direct binding of FIV Gag peptides to Tsg101. In contrast, mutagenesis of a potential Alix-binding motif in FIV Gag did not affect FIV release. Similarly, expression of the HIV-1/EIAV Gag-binding domain of Alix (Alix-V) did not disrupt FIV budding, and FIV Gag peptides showed no affinity for Alix-V. Our data demonstrate that FIV relies predominantly on a Tsg101-binding PSAP motif in the C terminus of Gag to promote virus release in HeLa cells, and this budding mechanism is highly conserved in feline cells. PMID:18094166

Luttge, Benjamin G; Shehu-Xhilaga, Miranda; Demirov, Dimiter G; Adamson, Catherine S; Soheilian, Ferri; Nagashima, Kunio; Stephen, Andrew G; Fisher, Robert J; Freed, Eric O

2008-03-01

364

Elevations, plan and section PP of main entrance. San Bernardino ...  

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

Elevations, plan and section PP of main entrance. San Bernardino Valley Union Junior College, Library Building. Howard E. Jones, Architect, San Bernardino, California. Sheet 9, 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

365

1. EXTERIOR VIEW, LOOKING WEST WITH FRONT FACADE AND ENTRANCE ...  

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

1. EXTERIOR VIEW, LOOKING WEST WITH FRONT FACADE AND ENTRANCE TO FORMER TCI-US STEEL COMPANY BATHHOUSE FOR WHITE ORE MINERS. - Tennessee Coal & Iron-U.S. Steel Surface Plant, Company Bathhouse for White Ore Miners, East of State Route 150 on South slope of Red Mountain, Bessemer, Jefferson County, AL

366

1. EXTERIOR VIEW, LOOKING SOUTH, WITH SIDE FACADE AND ENTRANCE ...  

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

1. EXTERIOR VIEW, LOOKING SOUTH, WITH SIDE FACADE AND ENTRANCE TO THE FORMER TCI-US STEEL COMPANY BATHHOUSE FOR COLORED ORE MINERS. - Tennessee Coal & Iron-U.S. Steel Surface Plant, Company Bathhouse for Black Ore Miners, East of State Route 150 on South slope of Red Mountain, Bessemer, Jefferson County, AL

367

2. WEST FRONT ENTRANCE, WITH OWNERS MR. & MRS. ISACC ...  

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

2. WEST FRONT ENTRANCE, WITH OWNERS MR. & MRS. ISACC N. HAGAN (WHO CONTRACTED WITH FRANK LLOYD WRIGHT FOR THE DESIGN OF THIS HOUSE) - Isaac N. Hagan House, Kentuck Knob, U.S. Route 40 vicinity (Stewart Township), Chalkhill, Fayette County, PA

368

4. VIEW OF THE FRONT ENTRANCE OF BUILDING 220. THROUGH ...  

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

4. VIEW OF THE FRONT ENTRANCE OF BUILDING 220. THROUGH THE SWINGING HARDWOOD DOUBLE DOORS AND SLIDING EXPANDED METAL/WOOD FRAMED DOORS IS THE CONTROL CENTER (LOCATED ON THE LEFT) AND BULL PEN (STRAIGHT AHEAD). - U.S. Naval Base, Pearl Harbor, Brig, Neville Way near Ninth Street at Marine Barracks, Pearl City, Honolulu County, HI

369

42. VIEW OF MARISCAL QUICKSILVER MINE ENTRANCE TWENTY YARDS SOUTHWEST ...  

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

42. VIEW OF MARISCAL QUICKSILVER MINE ENTRANCE TWENTY YARDS SOUTHWEST OF MAIN SHAFT LOOKING NORTHWEST. MINE CLOSURE BY PARK SERVICE, 1995. NOTE CONCRETE FOUNDATIONS IN THE CENTER OF IMAGE BEHIND OPENING FOR MAIN-SHAFT HOIST. - Mariscal Quicksilver Mine & Reduction Works, Terlingua, Brewster County, TX

370

ENTRANCE TO GOLD AREA SECURITY ROOM IN BASEMENT, LOCATED IN ...  

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

ENTRANCE TO GOLD AREA SECURITY ROOM IN BASEMENT, LOCATED IN BOTTOM OF ORIGINAL WET-BUCKET ELEVATOR SHAFT, ADJACENT TO DIESTER TABLE ROOM. NOTE BOARD WITH INDIVIDUAL TAGS FOR GOLD AREA EMPLOYEES. - Shenandoah-Dives Mill, 135 County Road 2, Silverton, San Juan County, CO

371

18. Dry Dock No. 4. Entrance Details (Frederic R. Harris, ...  

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

18. Dry Dock No. 4. Entrance Details (Frederic R. Harris, Inc., January 10, 1941). In Files of Cushman & Wakefield, Building No. 501, Philadelphia Naval Business Center. - Naval Base Philadelphia-Philadelphia Naval Shipyard, Dry Dock No. 4, Broad Street south of Government Avenue, Philadelphia, Philadelphia County, PA

372

8. INTERIOR, CONTROL AND INSTRUMENTATION ROOM. Looking southwest toward entrance ...  

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

8. INTERIOR, CONTROL AND INSTRUMENTATION ROOM. Looking southwest toward entrance and inner blast door. - Edwards Air Force Base, South Base Sled Track, Firing & Control Blockhouse for 10,000-foot Track, South of Sled Track at midpoint of 20,000-foot track, Lancaster, Los Angeles County, CA

373

West wing. Sidewalk streetscape shows art deco entrance door to ...  

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

West wing. Sidewalk streetscape shows art deco entrance door to service yard and access ramp (added ca. 1985) along the south façade of the west wing. - Jewish Community Center of San Francisco, 3200 California Street, San Francisco, San Francisco County, CA

374

3. Interior. Looking from balance room to the front entrance. ...  

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

3. Interior. Looking from balance room to the front entrance. Chemicals related to Edison's experiments on the extraction of latex for rubber from the goldenrod plant. Room is set up based on reconstruction research done in 1972. - Thomas A. Edison Laboratories, Building No. 2, West Orange, Essex County, NJ

375

The Martin Entrance Boundary of the Galton-Watson Process  

E-print Network

classifications. 60J80, 60J45. Keywords and phrases. Galton-Watson process, quasi-invariant measure, Martin1 The Martin Entrance Boundary of the Galton-Watson Process Gerold Alsmeyer Institut f¨ur Mathematische Statistik Fachbereich Mathematik Westf¨alische Wilhelms-Universit¨at M¨unster Einsteinstraße 62 D

Alsmeyer, Gerold

376

12. HISTORICAL VIEW OF FRONT ENTRANCE, BEFORE ADDITION OF SHELTERED ...  

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

12. HISTORICAL VIEW OF FRONT ENTRANCE, BEFORE ADDITION OF SHELTERED PORCH, SOUTH ELEVATION, 1907. Photocopied from Henry Pleasants's book, History of Old St. David's Church, published in 1915 by John C. Winston Co. - St. David's Church (Episcopal), Valley Forge Road (Newtown Township), Wayne, Delaware County, PA

377

IST for Industrial Engineering (ISTIE) Entrance to Minor Form  

E-print Network

IST for Industrial Engineering (ISTIE) Entrance to Minor Form Student Name Kumara, Professor of Industrial and Manufacturing Engineering,skumara@psu.edu, (310 Leonard Building, 863's major adviser and IST minor adviser, a copy of the approved minor application is given to Dr. Soundar

Petrick, Irene J.

378

21. VIEW OF THE ENTRANCE TO THE TUNNEL CONNECTING BUILDINGS ...  

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

21. VIEW OF THE ENTRANCE TO THE TUNNEL CONNECTING BUILDINGS 881 AND 883. THE TUNNEL WAS CONSTRUCTED IN 1957 TO TRANSPORT ENRICHED URANIUM COMPONENTS BETWEEN THE BUILDINGS. (1/98) - Rocky Flats Plant, General Manufacturing, Support, Records-Central Computing, Southern portion of Plant, Golden, Jefferson County, CO

379

5. PERSPECTIVE VIEW TO THE NORTHWEST SHOWING ENTRANCE TO CREW ...  

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

5. PERSPECTIVE VIEW TO THE NORTHWEST SHOWING ENTRANCE TO CREW SHELTER AND THE TAPERING SHAPE OF THE SOUTHEAST END WALL OF AR-8. - Edwards Air Force Base, South Base, Rammed Earth Aircraft Dispersal Revetments, Western Shore of Rogers Dry Lake, Boron, Kern County, CA

380

163. GENERAL VIEW OF MAIN ENTRANCE. VIEW EAST DOWN ROGER ...  

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

163. GENERAL VIEW OF MAIN ENTRANCE. VIEW EAST DOWN ROGER WILLIAMS WAY SHOWING, FROM LEFT TO RIGHT, THE DAVISVILLE PERIMETER FENCE, MAIN GATE COMPLEX, AND THE MAIN RAIL SPUR LEADING INTO THE BASE. - Quonset Point Naval Air Station, Roger Williams Way, North Kingstown, Washington County, RI

381

103. CANAL AT THE ENTRANCE TO THE POMPTON FEEDER NEAR ...  

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

103. CANAL AT THE ENTRANCE TO THE POMPTON FEEDER NEAR MOUNTAIN VIEW, NEW JERSEY. THE POMPTON FEEDER BOATS TO TRAVEL NORTH 4.26 MILES TO TO POMPTON AS WELL AS PROVIDING THE MAIN CANAL WITH WATER FROM GREENWOOD LAKE. A MODIFIED QUEEN POST TRUSS BRIDGE SPANS THE CANAL IN THE FOREGROUND. - Morris Canal, Phillipsburg, Warren County, NJ

382

View of the main entrance with basrelief limestone panel designed ...  

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

View of the main entrance with bas-relief limestone panel designed by C. Paul Jennwein upon which is inscribed "Lege Atque Ordine Omnia Fiunt" (translated as by law and order all is accomplished) - United States Department of Justice, Constitution Avenue between Ninth & Tenth Streets, Northwest, Washington, District of Columbia, DC

383

Service Building No. 620. Detail of north elevation and entrance ...  

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

Service Building No. 620. Detail of north elevation and entrance to substation & windowns in top of elevator shafts no. 2 & stair no. 1 & section thru substation (dry dock associates, June 12, 1941). In files of Cushman & Wakefield, building 501, Philadelphia Naval Business Center. - Naval Base Philadelphia-Philadelphia Naval Shipyard, Service Building, Dry Docks No. 4 & 5, League Island, Philadelphia, Philadelphia County, PA

384

34. EXTERIOR, VIEW OF QUARTERROUND ENCLOSURE AND ENTRANCE TO THE ...  

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

34. EXTERIOR, VIEW OF QUARTER-ROUND ENCLOSURE AND ENTRANCE TO THE BUTLER'S PANTRY ON THE WEST (REAR) ELEVATION FROM THE SOUTH, WITH SCALE - Mark Twain House, 351 Farmington Avenue (corrected from original address of 531 Farmington Avenue), Hartford, Hartford County, CT

385

35. EXTERIOR, VIEW OF QUARTERROUND ENCLOSURE AND ENTRANCE TO THE ...  

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

35. EXTERIOR, VIEW OF QUARTER-ROUND ENCLOSURE AND ENTRANCE TO THE BUTLER'S PANTRY ON THE WEST (REAR) ELEVATION FROM THE SOUTH, WITHOUT SCALE - Mark Twain House, 351 Farmington Avenue (corrected from original address of 531 Farmington Avenue), Hartford, Hartford County, CT

386

2. VIEW OF WEST WALL SHOWING MAIN ENTRANCE INTO SOUTH ...  

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

2. VIEW OF WEST WALL SHOWING MAIN ENTRANCE INTO SOUTH LOBBY AND ALUMINUM VESTIBULE ADDED IN RECENT YEARS. ELEVATOR WILL BE CONSTRUCTED TO THE RIGHT OF THE DOORWAY IN THE NORTHWEST CORNER OF THE LOBBY. - Tillamook County Courthouse, 201 Laurel Avenue, Tillamook, Tillamook County, OR

387

56. View of street level entrance to parking garage elevators ...  

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

56. View of street level entrance to parking garage elevators and detail of aluminum and glass connection to brick from east side of 1946/1948 store for homes and parking garage. - Rich's Downtown Department Store, 45 Broad Street, Atlanta, Fulton County, GA

388

View of Arcade interior at entrance to Snack House Restaurant. ...  

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

View of Arcade interior at entrance to Snack House Restaurant. Note scored plaster detail replicating stone construction joints on brick rearing walls, and detailed plaster relief panels. Various color schemed from panels and cornice details are visible throughout the building and in historic photographs - Post Office Arcade, 2118 First Street, Fort Myers, Lee County, FL

389

Entrance of hot pyroclastic flows into the sea: experimental observations  

Microsoft Academic Search

The entrance of hot pyroclastic flows into water has been observed in a series of experiments in which shooting granular flows of hot ignimbrite ash (𙟓 °C), of bulk density near that of water, run down a smooth chute and enter a water-filled tank at an angle of 26°. Flows of relatively cool ash (250 °C. Mixing across the water

Armin Freundt

2003-01-01

390

3. ONTARIO MINE. ADIT ENTRANCE WITH TIN ROOF. TIP TOP ...  

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

3. ONTARIO MINE. ADIT ENTRANCE WITH TIN ROOF. TIP TOP IS LOCATED IN LINE WITH 'Y' BRANCH AND THE TAILING PILE FOR TIP TOP IS VISIBLE JUST TO RIGHT OF IT. CAMERA POINTED SOUTH-SOUTHEAST. - Florida Mountain Mining Sites, Ontario Mine, Northwest side of Florida Mountain, Silver City, Owyhee County, ID

391

South entrance, plan, section, & detail. San Bernardino Valley Union ...  

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

South entrance, plan, section, & detail. San Bernardino Valley Union Junior College, Science Building. Detailed drawings of tile work, wrought iron, and art stone, Howard E. Jones, Architect, San Bernardino, California. Sheet 6, job no. 311. Scale 1.2 inch to the foot. February 15, 1927. - San Bernardino Valley College, Life Science Building, 701 South Mount Vernon Avenue, San Bernardino, San Bernardino County, CA

392

1. Credit PSR. This view captures the main entrance to ...  

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

1. Credit PSR. This view captures the main entrance to the Administration/Shops Building, constructed in 1963, looking north northeast (30°). The plaque at the base of the flagpole commemorates the first firing of a liquid-fueled rocket engine at Test Stand "A" in 1945. - Jet Propulsion Laboratory Edwards Facility, Administration & Shops Building, Edwards Air Force Base, Boron, Kern County, CA

393

Detail, view, underside of halfthrough girder span over entrance to ...  

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

Detail, view, underside of half-through girder span over entrance to scrap yard at western end of trestle. Note that abutment is slightly skewed. - Pennsylvania Railroad, French Creek Trestle, Spanning French Creek, north of Paradise Street, Phoenixville, Chester County, PA

394

DETAIL VIEW, MAIN ENTRANCE GATES, SHOWING A WINGED HOURGLASS MOTIF, ...  

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

DETAIL VIEW, MAIN ENTRANCE GATES, SHOWING A WINGED HOURGLASS MOTIF, WHICH REFERS TO THE QUICK PASSAGE OF TIME AND THE SHORTNESS OF HUMAN LIFE. USE OF THIS MOTIF WAS A CARRYOVER FROM THE MCARTHUR GATES. - Woodlands Cemetery, 4000 Woodlands Avenue, Philadelphia, Philadelphia County, PA

395

4. VIEW LOOKING WEST FROM ELM STREET AT THE ENTRANCE ...  

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

4. VIEW LOOKING WEST FROM ELM STREET AT THE ENTRANCE TO THE ELM CITY PLANT. NOTE TILE ROOF AND COLONIAL REVIVAL DESIGN MOTIFS. THE BOILER STACK IS VISIBLE ON THE LEFT. - Elm City Cotton Mill, 1000 Elm Street, La Grange, Troup County, GA

396

22. View of vehicle entrance to passageway link system taken ...  

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

22. View of vehicle entrance to passageway link system taken from looking west. Note DR 3 antenna in background left. - Clear Air Force Station, Ballistic Missile Early Warning System Site II, One mile west of mile marker 293.5 on Parks Highway, 5 miles southwest of Anderson, Anderson, Denali Borough, AK

397

"Dog House" or vestibule at the secondstory entrance located at ...  

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

"Dog House" or vestibule at the second-story entrance located at the intersection of the west Verandah of the south wing and the south Verandah of the rotunda extension. - U. S. Naval Asylum, Biddle Hall, Gray's Ferry Avenue, Philadelphia, Philadelphia County, PA

398

PRIMARY ENTRANCE INTO THE JENNE FARM, WEST FAÇADE. (The Jenne ...  

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

PRIMARY ENTRANCE INTO THE JENNE FARM, WEST FAÇADE. (The Jenne Barn has board and batten exterior cladding and sits above-grade on a poured concrete foundation. The barn is painted red with white trim. This door is painted green.) - Jenne Farm, Barn, 538 Engle Road, Coupeville, Island County, WA

399

School entrance recommendation: a question of age or development?  

Microsoft Academic Search

Fixed cutoff dates regulating school entry create disadvantages for children who are young relative to their classmates. Early and late school enrollment, though, might mitigate these disadvantages. In this paper, we analyze in a first step which factors determine school entry, if entrance screenings allow for early and late enrollment. Second, we study whether children benefit from a delayed school

Julia Horstschräer; Grit Muehler

2012-01-01

400

School Entrance Recommendation: A Question of Age or Development?  

ERIC Educational Resources Information Center

Fixed cutoff dates regulating school entry create disadvantages for children who are young relative to their classmates. Early and late school enrollment, though, might mitigate these disadvantages. In this paper, we analyze in a first step which factors determine school entry, if entrance screenings allow for early and late enrollment. Second, we…

Horstschräer, Julia; Muehler, Grit

2014-01-01

401

Environmental Science and Engineering Entrance examination, 95.3.11  

E-print Network

with each other. (10 %) 2. Draw a figure and describe the basic components of a fuel cell system includingEnvironmental Science and Engineering Entrance examination, 95.3.11 1. Waste management includes cycle reprocessing for nuclear reactor. (10 %) 4. Draw a figure and explain the dose-response curves

Huang, Haimei

402

UW China Hong Kong Entrance Scholarship University of Waterloo ID#  

E-print Network

UW ­ China Hong Kong Entrance Scholarship Name: University of Waterloo ID#: Program Applied of Waterloo who currently lives in or who previously lived in Hong Kong or mainland China. Candidates must also intend to return to Hong Kong or China after graduation. Selection will be based on academic

Le Roy, Robert J.

403

A permeability barrier surrounds taste buds in lingual epithelia.  

PubMed

Epithelial tissues are characterized by specialized cell-cell junctions, typically localized to the apical regions of cells. These junctions are formed by interacting membrane proteins and by cytoskeletal and extracellular matrix components. Within the lingual epithelium, tight junctions join the apical tips of the gustatory sensory cells in taste buds. These junctions constitute a selective barrier that limits penetration of chemosensory stimuli into taste buds (Michlig et al. J Comp Neurol 502: 1003-1011, 2007). We tested the ability of chemical compounds to permeate into sensory end organs in the lingual epithelium. Our findings reveal a robust barrier that surrounds the entire body of taste buds, not limited to the apical tight junctions. This barrier prevents penetration of many, but not all, compounds, whether they are applied topically, injected into the parenchyma of the tongue, or circulating in the blood supply, into taste buds. Enzymatic treatments indicate that this barrier likely includes glycosaminoglycans, as it was disrupted by chondroitinase but, less effectively, by proteases. The barrier surrounding taste buds could also be disrupted by brief treatment of lingual tissue samples with DMSO. Brief exposure of lingual slices to DMSO did not affect the ability of taste buds within the slice to respond to chemical stimulation. The existence of a highly impermeable barrier surrounding taste buds and methods to break through this barrier may be relevant to basic research and to clinical treatments of taste. PMID:25209263

Dando, Robin; Pereira, Elizabeth; Kurian, Mani; Barro-Soria, Rene; Chaudhari, Nirupa; Roper, Stephen D

2015-01-01

404

Molecular and Pathogenetic Aspects of Tumor Budding in Colorectal Cancer  

PubMed Central

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.

Dawson, Heather; Lugli, Alessandro

2015-01-01

405

Dormancy cycling and persistence of seeds in soil of a cold desert halophyte shrub  

PubMed Central

Background and Aims Formation of seed banks and dormancy cycling are well known in annual species, but not in woody species. In this study it was hypothesized that the long-lived halophytic cold desert shrub Kalidium gracile has a seed bank and dormancy cycling, which help restrict germination to a favourable time for seedling survival. Methods Fresh seeds were buried in November 2009 and exhumed and tested for germination monthly from May 2010 to December 2011 over a range of temperatures and salinities. Germination recovery and viability were determined after exposure to salinity and water stress. Seedling emergence and dynamics of the soil seed bank were investigated in the field. Key Results Seeds of K. gracile had a soil seed bank of 7030 seeds m?2 at the beginning of the growing season. About 72 % of the seeds were depleted from the soil seed bank during a growing season, and only 1·4 % of them gave rise to seedlings that germinated early enough to reach a stage of growth at which they could survive to overwinter. About 28 % of the seeds became part of a persistent soil seed bank. Buried seeds exhibited an annual non-dormancy/conditional dormancy (ND/CD) cycle, and germination varied in sensitivity to salinity during the cycle. Dormancy cycling is coordinated with seasonal environmental conditions in such a way that the seeds germinate in summer, when there is sufficient precipitation for seedling establishment. Conclusions Kalidium gracile has three life history traits that help ensure persistence at a site: a polycarpic perennial life cycle, a persistent seed bank and dormancy cycling. The annual ND/CD cycle in seeds of K. gracile contributes to seedling establishment of this species in the unpredictable desert environment and to maintenance of a persistent soil seed bank. This is the first report of a seed dormancy cycle in a cold desert shrub. PMID:24249808

Cao, Dechang; Baskin, Carol C.; Baskin, Jerry M.; Yang, Fan; Huang, Zhenying

2014-01-01

406

Water deficit and induction of summer dormancy in perennial Mediterranean grasses  

PubMed Central

Background and Aims Summer dormancy is a trait conferring superior drought survival in Mediterranean perennial grasses. As the respective roles of environmental factors and water deficit on induction of summer dormancy are unclear, the effect of intense drought were tested under contrasting day lengths in a range of forage and native grasses. Methods Plants of Poa bulbosa, Dactylis glomerata ‘Kasbah’ and Lolium arundinaceum ‘Flecha’ were grown in pots (a) from winter to summer in a glasshouse and subjected to either an early or a late-spring drought period followed by a summer water deficit and (b) in controlled conditions, with long days (LD, 16 h) or short days (SD, 9 h) and either full irrigation or water deficit followed by rehydration. Leaf elongation, senescence of aerial tissues and dehydration of basal tissues were measured to assess dormancy. Endogenous abscisic acid (ABA) in basal tissues was determined by monoclonal immunoassay analysis. Key Results Even under irrigation, cessation of leaf elongation, senescence of lamina and relative dehydration of basal tissues were triggered only by a day length longer than 13 h 30 min (late spring and LD) in plants of Poa bulbosa and Dactylis glomerata ‘Kasbah’ which exhibit complete dormancy. Plants of Lolium arundinaceum ‘Flecha’ maintained leaf growth under irrigation irrespective of the day length since its dormancy is incomplete. ABA concentrations were not higher during late-spring drought than early, and could not be associated with spring dormancy induction. In summer, ABA concentration in bulbs of the desiccation-tolerant Poa were greater than in basal tissues of other species. Conclusions The results of both experiments tend to invalidate the hypothesis that water deficit has a role in early summer-dormancy induction in the range of tested grasses. However, a late-spring drought tends to increase plant senescence and ABA accumulation in basal tissues of forage grasses which could enhance summer drought survival. PMID:19369219

Volaire, Florence; Seddaiu, Giovanna; Ledda, Luigi; Lelievre, François

2009-01-01

407

Seed dormancy and germination in Jeffersonia dubia (Berberidaceae) as affected by temperature and gibberellic acid.  

PubMed

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

Rhie, Y H; Lee, S Y; Kim, K S

2015-03-01

408

SMAD signaling and redox imbalance cooperate to induce prostate cancer cell dormancy.  

PubMed

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 TFG?/BMP signaling and redox imbalance are required for the full induction of this dormancy signature and cell quiescence. Moreover, reconstruction experiments showed that TFG?/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 TGF?/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

Bui, Anh Thu; Laurent, Fanny; Havard, Maryline; Dautry, François; Tchénio, Thierry

2015-04-18

409

Genetic analysis of adaptive syndromes interrelated with seed dormancy in weedy rice (Oryza sativa).  

PubMed

Seed dormancy in rice interrelates to the weedy characteristics shattering, awn, black hull color, and red pericarp color. A cross between the weedy strain SS18-2 and the breeding line EM93-1 was developed to investigate the genetic basis and adaptive significance of these interrelationships. These characteristics or their components differed in average degree of dominance from -0.8 to 1.5, in heritability from 0.5 to 0.96, and in their contribution to phenotypic or genotypic variation in dormancy by up to 25%. Five dormancy, four shattering, and three awn-length quantitative trait loci (QTLs) were detected in the BC1 population replicated in 2 years. Two QTLs for hull color were identified, and the SS18-2-derived and EM93-1-derived alleles increased the intensity of black, and red or yellow pigmentations, respectively. The only QTL for pericarp color co-located with the red pericarp gene Rc, with the SS18-2-derived allele increasing the intensity of black and red pigmentations. Four of the five dormancy QTLs were flanked or bracketed by one to four QTLs for the interrelated characteristics. The QTL organization pattern indicates the central role of seed dormancy in adaptive syndromes for non-domesticated plants, implies that the elimination of dormancy from cultivars could arise from the selections against multiple interrelated characteristics, and challenges the use of dormancy genes at these loci in breeding varieties for resistance to pre-harvest sprouting (PHS). However, another QTL (qSD12) provides candidate gene(s) for PHS resistance because it has a large effect in the population and it is independent of the loci for interrelated characteristics. PMID:15782297

Gu, Xing-You; Kianian, Shahryar F; Hareland, Gary A; Hoffer, Barry L; Foley, Michael E

2005-04-01

410

Inflammation Activates the Interferon Signaling Pathways in Taste Bud Cells  

PubMed Central

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-? receptor IFNGR1, are co-expressed with the taste cell-type markers neuronal cell adhesion molecule and ?-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-? and IFN-? triggered the IFN-mediated signaling cascades, resulting in the phosphorylation of the downstream STAT1 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-? or IFN-? 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

Wang, Hong; Zhou, Minliang; Brand, Joseph; Huang, Liquan

2007-01-01

411

The Storage and Seasoning of Pecan Bud Wood.  

E-print Network

general. J. A. Evans (7) in 1920 demonstrated that patch buds could be successfully inserted in rough thick bark of limbs three or more inches in diameter. This possibility renders it especially valuable for top-working poor- or non-producing trees.... * * * The patch bud, or modified ring bud,'has become the most important method of top- working native pecan trees, and is rapidly replacing the whip graft: in the propagation of nursery trees." Though other methods, notably the bark graft, may be used...

Brison, Fred R. (Fred Robert)

1933-01-01

412

Role of relative humidity, temperature, and water status in dormancy alleviation of sunflower seeds during dry after-ripening  

PubMed Central

The effect of various combinations of temperature and relative humidity on dormancy alleviation of sunflower seeds during dry after-ripening was investigated. The rate of dormancy alleviation depended on both temperature and embryo moisture content (MC). Below an embryo MC of 0.1 g H2O g?1 dw, dormancy release was faster at 15 °C than at higher temperatures. This suggests that dormancy release at low MC was associated with negative activation energy, supported by Arrhenius plots, and low Q10 values. At higher MC, the rate of dormancy alleviation increased with temperature, correlating well with the temperature dependence of biochemical processes. These findings suggests the involvement of two distinct cellular mechanisms in dormancy release; non-enzymatic below 0.1 g H2O g?1 dw and associated with active metabolism above this value. The effects of temperature on seed dormancy release above the threshold MC were analysed using a population-based thermal time approach and a model predicting the rate of dormancy alleviation is provided. Sunflower embryo dormancy release was effective at temperatures above 8 °C (the base temperature for after-ripening, TbAR, was 8.17 °C), and the higher the after-ripening temperature above this threshold value, the higher was the rate of dormancy loss. Thermodynamic analyses of water sorption isotherms revealed that dormancy release was associated with less bound water and increased molecular mobility within the embryonic axes but not the cotyledons. It is proposed that the changes in water binding properties result from oxidative processes and can, in turn, allow metabolic activities. PMID:20978143

Bazin, J.; Batlla, D.; Dussert, S.; El-Maarouf-Bouteau, H.; Bailly, C.

2011-01-01

413

Salamander and Mouse How are the positions of the limb buds determined?  

E-print Network

. Fgf10 expression stabilized in lateral mesoderm by Wnt2b in forelimb bud 3. Fgf10 expression stabilized in hindlimb bud by Wnt8c #12;Fig. 13.5 Fgf10 expression where limb buds form An extra (ectopic mesoderm 2. Fgf10 expression stabilized in lateral mesoderm by Wnt2b in forelimb bud 3. Fgf10 expression

414

Budding and fruitfulness of seedless grape in the São Francisco River Valley, northeast Brazil  

Microsoft Academic Search

th 2002, and Apr 8 th to 12 th 2002. The bud burst percentage was calculated by the ratio number of pushed buds and the total number of buds. The fertility index was obtained by dividing the total number of bunches by the total number of buds per plant. The results were statistically analyzed by the SAS computer program, and

Patrícia Coelho de S. Leão; Emanuel E. G da Silva

415

Taste Bud Cell Dynamics during Normal and Sodium-Restricted Development  

E-print Network

also had profound influences on taste bud growth kinetics, including an increased latency for cells bud cells. Examination of taste bud cell kinetics with 3 H-thymidine auto- radiography revealedTaste Bud Cell Dynamics during Normal and Sodium-Restricted Development SUSAN J. HENDRICKS,1 PETER

Hill, David L.

416

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...

417

33 CFR 334.390 - Atlantic Ocean south of entrance to Chesapeake Bay; firing range.  

Code of Federal Regulations, 2011 CFR

...Waters 3 2011-07-01 2011-07-01 false Atlantic Ocean south of entrance to Chesapeake Bay; firing range. 334...ZONE AND RESTRICTED AREA REGULATIONS § 334.390 Atlantic Ocean south of entrance to Chesapeake Bay; firing range....

2011-07-01

418

33 CFR 334.390 - Atlantic Ocean south of entrance to Chesapeake Bay; firing range.  

Code of Federal Regulations, 2014 CFR

...Waters 3 2014-07-01 2014-07-01 false Atlantic Ocean south of entrance to Chesapeake Bay; firing range. 334...ZONE AND RESTRICTED AREA REGULATIONS § 334.390 Atlantic Ocean south of entrance to Chesapeake Bay; firing range....

2014-07-01

419

33 CFR 334.390 - Atlantic Ocean south of entrance to Chesapeake Bay; firing range.  

Code of Federal Regulations, 2010 CFR

...Waters 3 2010-07-01 2010-07-01 false Atlantic Ocean south of entrance to Chesapeake Bay; firing range. 334...ZONE AND RESTRICTED AREA REGULATIONS § 334.390 Atlantic Ocean south of entrance to Chesapeake Bay; firing range....

2010-07-01

420

33 CFR 334.390 - Atlantic Ocean south of entrance to Chesapeake Bay; firing range.  

Code of Federal Regulations, 2013 CFR

...Waters 3 2013-07-01 2013-07-01 false Atlantic Ocean south of entrance to Chesapeake Bay; firing range. 334...ZONE AND RESTRICTED AREA REGULATIONS § 334.390 Atlantic Ocean south of entrance to Chesapeake Bay; firing range....

2013-07-01

421

33 CFR 334.390 - Atlantic Ocean south of entrance to Chesapeake Bay; firing range.  

Code of Federal Regulations, 2012 CFR

...Waters 3 2012-07-01 2012-07-01 false Atlantic Ocean south of entrance to Chesapeake Bay; firing range. 334...ZONE AND RESTRICTED AREA REGULATIONS § 334.390 Atlantic Ocean south of entrance to Chesapeake Bay; firing range....

2012-07-01

422

36 CFR 71.7 - Entrance fees for single-visit permits.  

Code of Federal Regulations, 2012 CFR

...of single-visit entrance fees charged at Designated Entrance Fee Areas for those persons not covered by either Golden Eagle or Golden Age Passports. (1) The fee for a single-visit permit applicable to those persons entering by...

2012-07-01

423

36 CFR 71.7 - Entrance fees for single-visit permits.  

Code of Federal Regulations, 2014 CFR

...of single-visit entrance fees charged at Designated Entrance Fee Areas for those persons not covered by either Golden Eagle or Golden Age Passports. (1) The fee for a single-visit permit applicable to those persons entering by...

2014-07-01

424

36 CFR 71.7 - Entrance fees for single-visit permits.  

Code of Federal Regulations, 2011 CFR

...of single-visit entrance fees charged at Designated Entrance Fee Areas for those persons not covered by either Golden Eagle or Golden Age Passports. (1) The fee for a single-visit permit applicable to those persons entering by...

2011-07-01

425

36 CFR 71.7 - Entrance fees for single-visit permits.  

Code of Federal Regulations, 2010 CFR

...of single-visit entrance fees charged at Designated Entrance Fee Areas for those persons not covered by either Golden Eagle or Golden Age Passports. (1) The fee for a single-visit permit applicable to those persons entering by...

2010-07-01

426

36 CFR 71.7 - Entrance fees for single-visit permits.  

Code of Federal Regulations, 2013 CFR

...of single-visit entrance fees charged at Designated Entrance Fee Areas for those persons not covered by either Golden Eagle or Golden Age Passports. (1) The fee for a single-visit permit applicable to those persons entering by...

2013-07-01

427

The Arabidopsis MYB96 transcription factor plays a role in seed dormancy.  

PubMed

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

Lee, Hong Gil; Lee, Kyounghee; Seo, Pil Joon

2015-03-01

428

An investigation of the production of rosebushes by the budding of understocks prior to rooting  

E-print Network

-112 Z. ) at least $0 minutes prior to budding. This was to encour- age slippage of the bark to make budd. ing easier. Each treatment of six cuttings in each' replicate was budded, stuck, firmed. in, and watered before the same treatment of the next... under the elastic bud-tie. Llhe, . the experiment was terminated, bud-ties were removed and tne buds were examined for signs of bud-take. None showed signs of union with the stock. In each case the bark could be peeled. back quite easily, and the bud...

Jordan, Jack Morgan

1966-01-01

429

Global Dormancy of Metastases Due to Systemic Inhibition of Angiogenesis  

PubMed Central

Autopsy studies of adults dying of non-cancer causes have shown that virtually all of us possess occult, cancerous lesions. This suggests that, for most individuals, cancer will become dormant and not progress, while only in some will it become symptomatic disease. Meanwhile, it was recently shown in animal models that a tumor can produce both stimulators and inhibitors of its own blood supply. To explain the autopsy findings in light of the preclinical research data, we propose a mathematical model of cancer development at the organism scale describing a growing population of metastases, which, together with the primary tumor, can exert a progressively greater level of systemic angiogenesis-inhibitory influence that eventually overcomes local angiogenesis stimulation to suppress the growth of all lesions. As a departure from modeling efforts to date, we look not just at signaling from and effects on the primary tumor, but integrate over this increasingly negative global signaling from all sources to track the development of total tumor burden. This in silico study of the dynamics of the tumor/metastasis system identifies ranges of parameter values where mutual angio-inhibitory interactions within a population of tumor lesions could yield global dormancy, i.e., an organism-level homeostatic steady state in total tumor burden. Given that mortality arises most often from metastatic disease rather than growth of the primary per se, this finding may have important therapeutic implications. PMID:24465399

Benzekry, Sébastien; Gandolfi, Alberto; Hahnfeldt, Philip

2014-01-01

430

Global dormancy of metastases due to systemic inhibition of angiogenesis.  

PubMed

Autopsy studies of adults dying of non-cancer causes have shown that virtually all of us possess occult, cancerous lesions. This suggests that, for most individuals, cancer will become dormant and not progress, while only in some will it become symptomatic disease. Meanwhile, it was recently shown in animal models that a tumor can produce both stimulators and inhibitors of its own blood supply. To explain the autopsy findings in light of the preclinical research data, we propose a mathematical model of cancer development at the organism scale describing a growing population of metastases, which, together with the primary tumor, can exert a progressively greater level of systemic angiogenesis-inhibitory influence that eventually overcomes local angiogenesis stimulation to suppress the growth of all lesions. As a departure from modeling efforts to date, we look not just at signaling from and effects on the primary tumor, but integrate over this increasingly negative global signaling from all sources to track the development of total tumor burden. This in silico study of the dynamics of the tumor/metastasis system identifies ranges of parameter values where mutual angio-inhibitory interactions within a population of tumor lesions could yield global dormancy, i.e., an organism-level homeostatic steady state in total tumor burden. Given that mortality arises most often from metastatic disease rather than growth of the primary per se, this finding may have important therapeutic implications. PMID:24465399

Benzekry, Sébastien; Gandolfi, Alberto; Hahnfeldt, Philip

2014-01-01

431

Studies on Cytokinin-Controlled Bud Formation in Moss Protonemata  

PubMed Central

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

Brandes, H.; Kende, H.

1968-01-01

432

Control of bud activation by an auxin transport switch.  

PubMed

In many plant species only a small proportion of buds yield branches. Both the timing and extent of bud activation are tightly regulated to produce specific branching architectures. For example, the primary shoot apex can inhibit the activation of lateral buds. This process is termed apical dominance and is dependent on the plant hormone auxin moving down the main stem in the polar auxin transport stream. We use a computational model and mathematical analysis to show that apical dominance can be explained in terms of an auxin transport switch established by the temporal precedence between competing auxin sources. Our model suggests a mechanistic basis for the indirect action of auxin in bud inhibition and captures the effects of diverse genetic and physiological manipulations. In particular, the model explains the surprising observation that highly branched Arabidopsis phenotypes can exhibit either high or low auxin transport. PMID:19805140

Prusinkiewicz, Przemyslaw; Crawford, Scott; Smith, Richard S; Ljung, Karin; Bennett, Tom; Ongaro, Veronica; Leyser, Ottoline

2009-10-13

433

Grapevine bud break prediction for cool winter climates  

NASA Astrophysics Data System (ADS)

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.

Nendel, Claas

2010-05-01

434

Dissecting the spatial structure of overlapping transcription in budding yeast  

E-print Network

This thesis presents a computational and algorithmic method for the analysis of high-resolution transcription data in the budding yeast Saccharomyces cerevisiae. We begin by describing a computational system for storing ...

Danford, Timothy W. (Timothy William), 1979-

2010-01-01

435

Innervation of the undifferentiated limb bud in rabbit embryo.  

PubMed Central

The concept that there are no nerves in the limb bud of mammalian embryos prior to differentiation has been re-examined. Rabbit embryos were collected at 260 and 290 hours gestation, which is prior to cartilage formation in the forelimb at 320 hours. Forelimb buds and adjacent neural tube were excised, fixed and embedded for light and electron microscopy. The limb buds were sectioned in two planes by serial 1 micrometer sections and inspected by light microscopy. Bundles of nerve fibres were seen within the proximal third of the limb bud, with distal ramification into adjacent zones of condensing mesenchyme. Electron microscopy confirmed the presence of axons and associated immature Schwann cells. These results demonstrate the existence of an anatomical framework through which a neurotrophic influence might be brought to bear upon mesenchyme prior to early differentiation. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 Fig. 6 Fig. 7 Fig. 8 Fig. 9 Fig. 10 PMID:7130041

Cameron, J; McCredie, J

1982-01-01

436

Tolerance of budding yeast Saccharomyces cerevisiae to ultra high pressure  

NASA Astrophysics Data System (ADS)

Our studies on the tolerance of plants and animals against very high pressure of several GPa have been extended to a smaller sized fungus, the budding yeast Saccharomyces cerevisiae. Several pieces of budding yeast (dry yeast) were sealed in a small teflon capsule with a liquid pressure medium fluorinate, and exposed to 7.5 GPa by using a cubic anvil press. The pressure was kept constant for various duration of time from 2 to 24 h. After the pressure was released, the specimens were brought out from the teflon capsule, and they were cultivated on a potato dextrose agar. It was found that the budding yeast exposed to 7.5 GPa for up to 6 h showed multiplication. However, those exposed to 7.5 GPa for longer than 12 h were found dead. The high pressure tolerance of budding yeast is a little weaker than that of tardigrades.

Shibata, M.; Torigoe, M.; Matsumoto, Y.; Yamamoto, M.; Takizawa, N.; Hada, Y.; Mori, Y.; Takarabe, K.; Ono, F.

2014-05-01

437

The hormonal regulation of bud outgrowth in Phaseolus vulgaris L.  

PubMed

Aqueous solutions of indole acetic acid, kinetin, gibberellic acid and abscisic acid were applied singly and in combination to the decapitated stem stump of Phaseolus seedlings. Application of indole acetic acid will not completely replace the intact stem apex with regard to the inhibition of lateral bud extension. The greatest inhibition of bud growth is obtained when indole acetic acid is applied in combination with both kinetin and abscisic acid. Treatment with gibberellic acid causes massive bud growth even in the presence of indole acetic acid, kinetin and abscisic acid. Although both abscisic acid and kinetin have only a slight promoting effect on bud outgrowth when applied singly, these hormones will modify the effects of indole acetic acid and gibberellic acid. PMID:24499834

Hillman, J

1970-09-01

438

Proteome analysis of Norway maple (Acer platanoides L.) seeds dormancy breaking and germination: influence of abscisic and gibberellic acids  

Microsoft Academic Search

BACKGROUND: Seed dormancy is controlled by the physiological or structural properties of a seed and the external conditions. It is induced as part of the genetic program of seed development and maturation. Seeds with deep physiological embryo dormancy can be stimulated to germinate by a variety of treatments including cold stratification. Hormonal imbalance between germination inhibitors (e.g. abscisic acid) and

Tomasz A Paw?owski

2009-01-01

439

DEVELOPMENT AND STANDARDIZATION OF A SIMPLE TECHNIQUE FOR BREAKING SEED DORMANCY IN SUNFLOWER (HELIANTHUS ANNUUS L.) GENOTYPES  

Technology Transfer Automated Retrieval System (TEKTRAN)

Seed dormancy causes a great problem in efficient seed production of sunflower. Attempts have been made to develop simple techniques for breaking seed dormancy. In the first experiment, different techniques were evaluated using treatments such as a growth regulator, Ethrel, priming (water soaking fo...

440

Studies in seed dormancy : VII. The abscisic acid content of the seeds and fruits of Corylus avellana L.  

PubMed

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

Williams, P M; Ross, J D; Bradbeer, J W

1973-12-01

441

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...

442

Effect of low temperature on dormancy breaking and growth after planting in lily bulblets regenerated in vitro  

Microsoft Academic Search

Lilies regenerating on scale segments may develop dormancy in vitro depending on the culture conditions. The dormancy is broken by storage for several weeks at a low temperature (5 °C). The effect of the low temperature on sprouting, time of leaf emergence and further bulb growth was studied. Dormant and non-dormant bulblets were regenerated in vitro on bulb scale segments

Merel M. Langens-Gerrits; William B. M. Miller; Anton F. Croes; Klerk de G. J. M

2003-01-01

443

Bioengineered Teeth from Cultured Rat Tooth Bud Cells  

Microsoft Academic Search

The recent bioengineering of complex tooth structures from pig tooth bud tissues suggests the potential for the regeneration of mammalian dental tissues. We have improved tooth bioengineering methods by comparing the utility of cultured rat tooth bud cells obtained from three-to seven-day post-natal (dpn) rats for tooth-tissue-engineering applications. Cell-seeded biodegradable scaffolds were grown in the omenta of adult rat hosts

M. T. Duailibi; S. E. Duailibi; C. S. Young; J. D. Bartlett; J. P. Vacanti; P. C. Yelick

2004-01-01

444

Notch signalling defines critical boundary during budding in Hydra.  

PubMed

Boundary formation is an important mechanism of development and has been studied in a number of bilaterian model organisms where it is often controlled by Notch, FGF and Wnt signalling. Tissue boundaries are also formed in simple pre-bilaterian animals. The boundary between parent and bud during asexual reproduction in the fresh water polyp Hydra vulgaris is an example. The Hydra homolog of the FGF-receptor FGFR (kringelchen) and some components of the Wnt signalling pathway are expressed at this boundary, but their precise functions are unknown. In this work we have discovered an important role for Notch signalling at this boundary. Notch signalling is needed to sharpen the kringelchen expression zone during the final budding stages from an initially broad band into a clear line demarcating the boundary between bud and parent. Expression of the Notch target gene HyHes and the putative matrix metalloprotease MMP-A3 was observed at the boundary shortly before the bud began to constrict and differentiate foot cells. When Notch signalling was inhibited with the presenilin inhibitor DAPT the expression pattern for kringelchen changed dramatically into a diffused pattern. The expression of both HyHes and MMP-A3 was abolished. Moreover, morphogenesis of the bud was not completed and buds did not constrict, failed to form a foot and never detached from the parent. This resulted in the formation of two-headed animals. We suggest that the function of Notch signalling during budding in Hydra is in promoting the formation of two stripes of differing gene expression, which are needed to differentiate the foot of the bud and a progressing narrowing of the mesoglea on the side of the parent. PMID:20534380

Münder, Sandra; Käsbauer, Tina; Prexl, Andrea; Aufschnaiter, Roland; Zhang, Xiaoming; Towb, Par; Böttger, Angelika

2010-08-01

445

Brian Smith Memorial Entrance Scholarship This Scholarship is not currently open for  

E-print Network

Brian Smith Memorial Entrance Scholarship This Scholarship is not currently open for applications update scholarships@waikato.ac.nz for other funding opportunities. #12;Brian Smith Memorial Entrance Scholarship REGULATIONS FOR THE BRIAN SMITH MEMORIAL ENTRANCE SCHOLARSHIP BACKGROUND The Brian Smith Memorial

Waikato, University of

446

Micropropagation of Helleborus through axillary budding.  

PubMed

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 ?-naphthoxyacetic acid, and 2 mg/L isopentenyl adenine develop shoots after 16 weeks of culture under 16 h light regime, 50-60 ?mol/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

Beruto, Margherita; Viglione, Serena; Bisignano, Alessandro

2013-01-01

447

Heterochromatin structure: lessons from the budding yeast.  

PubMed

The eukaryotic genome can be roughly divided into euchromatin and heterochromatin domains that are structurally and functionally distinct. Heterochromatin is characterized by its high compactness and its inhibitory effect on DNA transactions such as gene expression. Formation of heterochromatin involves special histone modifications and the recruitment and spread of silencing complexes and causes changes in the primary and higher order structures of chromatin. The past two decades have seen dramatic advances in dissecting the molecular aspects of heterochromatin because of the identification of the histone code for heterochromatin as well as its writers and erasers (histone-modifying enzymes) and readers (silencing factors recognizing histone modifications). How heterochromatic histone modifications and silencing factors contribute to the special primary and higher order structures of heterochromatin has begun to be understood. The budding yeast Saccharomyces cerevisiae has long been used as a model organism for heterochromatin studies. Results from these studies have contributed significantly to the elucidation of the general principles governing the formation, maintenance, and function of heterochromatin. This review is focused on investigations into the structural aspects of heterochromatin in S. cerevisiae. Current understanding of other aspects of heterochromatin including how it promotes gene silencing and its epigenetic inheritance is briefly summarized. PMID:25355678

Bi, Xin

2014-10-01

448

19. PRIVATE SIDE ENTRANCE ADDED IN 1921 TO GIVE BARRIERFREE ...  

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

19. PRIVATE SIDE ENTRANCE ADDED IN 1921 TO GIVE BARRIER-FREE ACCESS FROM THE DRIVEWAY TO THE ELEVATOR. Wrought iron railings, extended upper step of stoop (indicated by the darker concrete between the two vertical posts), and wooden ramp added by the National Trust to meet modern barrier-free access codes, circa 1980. - Woodrow Wilson House, 2340 South S Street, Northwest, Washington, District of Columbia, DC

449

Section AA through main entrance gates & west stairs. San ...  

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

Section AA through main entrance gates & west stairs. San Bernardino Valley Union Junior College, Science Building. Also includes plans and sections of boys' and girls' toilets. Howard E. Jones, Architect, San Bernardino, California. Sheet 5, job no. 311. Scales 1/4 inch to the foot (section AA) and 1/2 inch to the foot (toilet rooms). February 15, 1927. - San Bernardino Valley College, Life Science Building, 701 South Mount Vernon Avenue, San Bernardino, San Bernardino County, CA

450

2. View from the mansion formal entrance driveway toward the ...  

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

2. View from the mansion formal entrance driveway toward the big meadow at the Billings Farm & Museum. The driveway is flanked by granite gateposts surmounted by wrought iron urn lamps. The view includes a manicured hemlock hedge (Tsuga canadensis) retained by a stone wall at left, and white birch (Betula species) under-planted with ferns at center. - Marsh-Billings-Rockefeller National Historical Park, 54 Elm Street, Woodstock, Windsor County, VT

451

Elevation and plan of main entrance. San Bernardino Valley Union ...  

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

Elevation and plan of main entrance. San Bernardino Valley Union Junior College, Library Building. Also includes full size detail of mullion for iron gates. Howard E. Jones, Architect, San Bernardino, California. Sheet 5, 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

452

A study of driver behavior on freeway entrance ramps  

E-print Network

25 San Antonio Study Driver Classification. . Freeway Evaluation Area. Vehicle Entry Paths Entry Speeds Ramp Stoppages . Houston Study Driver Classification. F reeway Eva lu at i on Area . Vehicle Entry Paths Entry Speeds Ramp Stoppages... CAMERA (B) 20 The determination of the vehicle characteristics (paths of entry and entry speeds) was made possible by positioning reference markers at pre- determined locations on the entrance ramp and the acceleration lane. These reference markers...

Edwards, Fred Huntley

1961-01-01

453

Seed dormancy cycling in Arabidopsis: chromatin remodelling and regulation of DOG1 in response to seasonal environmental signals.  

PubMed

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

Footitt, Steven; Müller, Kerstin; Kermode, Allison R; Finch-Savage, William E

2015-02-01

454

The role of the testa during development and in establishment of dormancy of the legume seed.  

PubMed

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

Smýkal, Petr; Vernoud, Vanessa; Blair, Matthew W; Soukup, Aleš; Thompson, Richard D

2014-01-01

455

The role of the testa during development and in establishment of dormancy of the legume seed  

PubMed Central

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

Smýkal, Petr; Vernoud, Vanessa; Blair, Matthew W.; Soukup, Aleš; Thompson, Richard D.

2014-01-01

456

Seed Maturation Regulators Are Related to the Control of Seed Dormancy in Wheat (Triticum aestivum L.)  

PubMed Central

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

Rikiishi, Kazuhide; Maekawa, Masahiko

2014-01-01

457

ABA crosstalk with ethylene and nitric oxide in seed dormancy and germination  

PubMed Central

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

Arc, Erwann; Sechet, Julien; Corbineau, Françoise; Rajjou, Loïc; Marion-Poll, Annie

2013-01-01

458

Arabidopsis histone demethylases LDL1 and LDL2 control primary seed dormancy by regulating DELAY OF GERMINATION 1 and ABA signaling-related genes  

PubMed Central

Seed dormancy controls germination and plays a critical role in regulating the beginning of the life cycle of plants. Seed dormancy is established and maintained during seed maturation and is gradually broken during dry storage (after-ripening). The plant hormone abscisic acid (ABA) and DELAY OF GERMINATION1 (DOG1) protein are essential regulators of seed dormancy. Recent studies revealed that chromatin modifications are also involved in the transcription regulation of seed dormancy. Here, we showed that two Arabidopsis histone demethylases, LYSINESPECIFIC DEMETHYLASE LIKE 1 and 2 (LDL1 and LDL2) act redundantly in repressing of seed dormancy. LDL1 and LDL2 are highly expressed in the early silique developing stage. The ldl1 ldl2 double mutant displays increased seed dormancy, whereas overexpression of LDL1 or LDL2 in Arabidopsis causes reduced dormancy. Furthermore, we showed that LDL1 and LDL2 repress the expression of seed dormancy-related genes, including DOG1, ABA2 and ABI3 during seed dormancy establishment. Furthermore, genetic analysis revealed that the repression of seed dormancy by LDL1 and LDL2 requires DOG1, ABA2, and ABI3. Taken together, our findings revealed that LDL1 and LDL2 play an essential role in seed dormancy. PMID:25852712

Zhao, Minglei; Yang, Songguang; Liu, Xuncheng; Wu, Keqiang

2015-01-01

459

The Mode of Origin of Root Buds and Root Sprouts in the Clonal Tree Sassafras albidum (Lauraceae)  

Microsoft Academic Search

The developmental anatomy of root buds and root sprouts was examined in the clonal tree Sassafras albidum. Root samples from 13 clones that varied widely in age and vigor were sectioned and two types of buds were found, ''additional'' buds and ''reparative'' buds. Additional buds form during the early growth of uninjured roots and they perennate by growing outwards in

Michael J. Bosela; Frank W. Ewers

1997-01-01

460

A QTL located on chromosome 4A associated with dormancy in white- and red-grained wheats of diverse origin.  

PubMed

Improved resistance to preharvest sprouting in modern bread wheat (Triticum aestivum. L.) can be achieved via the introgression of grain dormancy and would reduce both the incidence and severity of damage due to unfavourable weather at harvest. The dormancy phenotype is strongly influenced by environmental factors making selection difficult and time consuming and this trait an obvious candidate for marker assisted selection. A highly significant Quantitative Trait Locus (QTL) associated with grain dormancy and located on chromosome 4A was identified in three bread wheat genotypes, two white- and one red-grained, of diverse origin. Flanking SSR markers on either side of the putative dormancy gene were identified and validated in an additional population involving one of the dormant genotypes. Genotypes containing the 4A QTL varied in dormancy phenotype from dormant to intermediate dormant. Based on a comparison between dormant red- and white-grained genotypes, together with a white-grained mutant derived from the red-grained genotype, it is concluded that the 4A QTL is a critical component of dormancy; associated with at least an intermediate dormancy on its own and a dormant phenotype when combined with the R gene in the red-grained genotype and as yet unidentified gene(s) in the white-grained genotypes. These additional genes appeared to be different in AUS1408 and SW95-50213. PMID:16133305

Mares, D; Mrva, K; Cheong, J; Williams, K; Watson, B; Storlie, E; Sutherland, M; Zou, Y

2005-11-01

461

GABA, its receptors, and GABAergic inhibition in mouse taste buds  

PubMed Central

Taste buds consist of at least three principal cell types that have different functions in processing gustatory signals — glial-like Type I cells, Receptor (Type II) cells, and Presynaptic (Type III) cells. Using a combination of Ca2+ imaging, single cell RT-PCR, and immunostaining, we show that ?-amino butyric acid (GABA) is an inhibitory transmitter in mouse taste buds, acting on GABA-A and GABA-B receptors to suppress transmitter (ATP) secretion from Receptor cells during taste stimulation. Specifically, Receptor cells express GABA-A receptor subunits ?2, ?, ?, as well as GABA-B receptors. In contrast, Presynaptic cells express the GABA-A?3 subunit and only occasionally GABA-B receptors. In keeping with the distinct expression pattern of GABA receptors in Presynaptic cells, we detected no GABAergic suppression of transmitter release from Presynaptic cells. We suggest that GABA may serve function(s) in taste buds in addition to synaptic inhibition. Finally, we also defined the source of GABA in taste buds: GABA is synthesized by GAD65 in Type I taste cells as well as by GAD67 in Presynaptic (Type III) taste cells and is stored in both those two cell types. We conclude that GABA is released during taste stimulation and possibly also during growth and differentiation of taste buds. PMID:21490220

Dvoryanchikov, Gennady; Huang, Yijen A; Barro-Soria, Rene; Chaudhari, Nirupa; Roper, Stephen D.

2012-01-01

462

Neurotrophin receptors in taste buds of adult zebrafish (Danio rerio).  

PubMed

TrkB plays crucial roles in the development and maintenance of taste buds in mammals. In this study we investigated the presence and cell localization of Trks (TrkA, TrkB and TrkC) in taste buds of the zebrafish (Danio rerio) using Western blot and immunohistochemistry. Proteins of 140 and 145 kDa, identified as full-length TrkA and TrkB, were detected. Conversely, the anti-TrkC antibody recognized a protein lower than expected (100 kDa). In agreement with these results the sensory cells of taste buds, displayed TrkA- and TrkB-like, but not TrkC-like, immunoreactivity. TrkA and TrkB co-existed in the same taste buds, but remains to be clarified whether or not they are co-expressed in the same cells. Present results demonstrate that as for mammals neurotrophins might play a role in sensory cells of the teleostean taste buds. PMID:14700728

Germana, A; González-Martínez, T; Catania, S; Laura, R; Cobo, J; Ciriaco, E; Vega, J A

2004-01-16

463

Are there efferent synapses in fish taste buds?  

PubMed

In fish, nerve fibers of taste buds are organized within the bud's nerve fiber plexus. It is located between the sensory epithelium consisting of light and dark elongated cells and the basal cells. It comprises the basal parts and processes of light and dark cells that intermingle with nerve fibers, which are the dendritic endings of the taste sensory neurons belonging to the cranial nerves VII, IX or X. Most of the synapses at the plexus are afferent; they have synaptic vesicles on the light (or dark) cells side, which is presynaptic. In contrast, the presumed efferent synapses may be rich in synaptic vesicles on the nerve fibers (presynaptic) side, whereas the cells (postsynaptic) side may contain a subsynaptic cistern; a flat compartment of the smooth endoplasmic reticulum. This structure is regarded as a prerequisite of a typical efferent synapse, as occurring in cochlear and vestibular hair cells. In fish taste buds, efferent synapses are rare and were found only in a few species that belong to different taxa. The significance of efferent synapses in fish taste buds is not well understood, because efferent connections between the gustatory nuclei of the medulla with taste buds are not yet proved. PMID:16217620

Reutter, Klaus; Witt, Martin

2004-12-01

464

Repellence of the red bud borer Resseliella oculiperda from grafted apple trees by impregnation of rubber budding strips with essential oils.  

PubMed

The red bud borer Resseliella oculiperda (Rübs.) is a pest insect of apple trees when rootstocks are grafted with scion buds by 'shield budding'. The female midges are attracted to the wounds of the grafted buds where they lay their eggs. The larvae feed on the cambium and destroy the buds completely or partially, leading to bad union of the buds with the rootstocks. Budding strips are used very often by growers to bind scion buds to rootstocks. These strips cannot prevent midges from reaching the damaged tissue. Chemical treatments applied to the grafts and other types of strip do not provide better protection against the pest and may cause other risks for growers. In orchard experiments in 2000 and 2001, the authors evaluated the repellent action provided by three essential oils and five compounds of plant origin against the midges by impregnating budding strips with them. The essential oils of lavender, Lavandula angustifolia (P. Mill.), and alpha-terpineol decreased the infestation of buds by more than 95 and 80% respectively. The other potential repellents tested [the essential oil of Juniperus virginiana (L.), citronellal, the essential oil of Cinnamomum camphora (L.) J. Presl, R-carvone, linalool and R-fenchone] decreased infestation by 67, 66, 51, 45, 37 and 25% respectively. The formulation and commercial development of budding strips impregnated with lavender oil is discussed. PMID:17421054

van Tol, Rob W H M; Swarts, Henk J; van der Linden, Anton; Visser, J H

2007-05-01

465

Physiology, morphology and phenology of seed dormancy break and germination in the endemic Iberian species Narcissus hispanicus (Amaryllidaceae)  

PubMed Central

Background and Aims Only very few studies have been carried out on seed dormancy/germination in the large monocot genus Narcissus. A primary aim of this study was to determine the kind of seed dormancy in Narcissus hispanicus and relate the dormancy breaking and germination requirements to the field situation. Methods Embryo growth, radicle emergence and shoot growth were studied by subjecting seeds with and without an emerged radicle to different periods of warm, cold or warm plus cold in natural temperatures outdoors and under controlled laboratory conditions. Key Results Mean embryo length in fresh seeds was approx. 1·31 mm, and embryos had to grow to 2·21 mm before radicle emergence. Embryos grew to full size and seeds germinated (radicles emerged) when they were warm stratified for 90 d and then incubated at cool temperatures for 30 d. However, the embryos grew only a little and no seeds germinated when they were incubated at 9/5, 10 or 15/4 °C for 30 d following a moist cold pre-treatment at 5, 9/5 or 10 °C. In the natural habitat of N. hispanicus, seeds are dispersed in late May, the embryo elongates in autumn and radicles emerge (seeds germinate) in early November; however, if the seeds are exposed to low temperatures before embryo growth is completed, they re-enter dormancy (secondary dormancy). The shoot does not emerge until March, after germinated seeds are cold stratified in winter. Conclusion Seeds of N. hispanicus have deep simple epicotyl morphophysiological dormancy (MPD), with the dormancy formula C1bB(root) – C3(epicotyl). This is the first study on seeds with simple MPD to show that embryos in advanced stages of growth can re-enter dormancy (secondary dormancy). PMID:21335326

Copete, Elena; Herranz, José M.; Ferrandis, Pablo; Baskin, Carol C.; Baskin, Jerry M.

2011-01-01

466

Cloning, Characterization, Regulation, and Function of DORMANCY-ASSOCIATED MADS-BOX Genes from Leafy Spurge  

Technology Transfer Automated Retrieval System (TEKTRAN)

DORMANCY-ASSOCIATED MADS-BOX (DAM) genes are transcription factors that have been linked to endodormancy induction. The evergrowing mutation in peach, which renders it incapable of entering endodormancy, resulted from a deletion in a series of DAM genes (Bielenberg et al. 2008). Likewise, DAM genes ...

467

TBK1 Regulates Prostate Cancer Dormancy through mTOR Inhibition12  

PubMed Central

The mechanisms that regulate hematopoietic stem cell (HSC) dormancy and self-renewal are well established and are largely dependent on signals emanating from the HSC niche. Recently, we found that prostate cancer (PCa) cells target the HSC niche in mouse bone marrow (BM) during metastasis. Little is known, however, as to how the HSC niche may regulate dormancy in cancer cells. In this study, we investigated the effects of TANK binding kinase 1 (TBK1) on PCa dormancy in the BM niche. We found that binding with niche osteoblasts induces the expression of TBK1 in PCa cells PC3 and C4-2B. Interestingly, TBK1 interacts with mammalian target of rapamycin (mTOR) and inhibits its function. Rapamycin, an mTOR inhibitor, induces cell cycle arrest of PCa cells and enhances chemotherapeutic resistance of PCa cells. As a result, the knockdown of TBK1 decreases PCa stem-like cells and drug resistance in vitro and in vivo. Taken together, these results strongly indicate that TBK1 plays an important role in the dormancy and drug resistance of PCa. PMID:24027431

Kim, Jin Koo; Jung, Younghun; Wang, Jingcheng; Joseph, Jeena; Mishra, Anjali; Hill, Elliott E; Krebsbach, Paul H; Pienta, Kenneth J; Shiozawa, Yusuke; Taichman, Russell S

2013-01-01

468

Tuber Dormancy Lasting Eight Years in the Wild Potato Solanum Jamesii  

Technology Transfer Automated Retrieval System (TEKTRAN)

The physiology of tuber dormancy is of practical interest for commercial potato as it is related to efficient storage of the crop, and vigorous and uniform sprouting of planted seed tubers. It is also of interest for germplasm preservation at the genebank. Since research is often advanced by study...

469

Tuber Dormancy Lasting Eight Years in the Wild Potato Solanum Jamesii  

Technology Transfer Automated Retrieval System (TEKTRAN)

Control of tuber dormancy is of interest for commercial potato production and for germplasm preservation in the genebank. Solanum jamesii plants were collected by the author from the wild in New Mexico and Arizona, USA in 1998 and grown in the greenhouse. Tubers harvested in 1999 were placed in pape...

470

Cell cycle activity and beta-tubulin accumulation during dormancy breaking of Acer platanoides L. seeds  

Microsoft Academic Search

Cell cycle events in embryo axes of Norway maple (Acer platanoides L.) seeds were studied during dormancy breaking by flow cytometric analyses of the nuclear DNA content and by immunodetection of ?-tubulin. Most embryonic nuclei of dry, fully matured seeds were arrested i