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101.
Yann Aubert Louis-Jérome Leba Cécilia Cheval Benoit Ranty Alain Vavasseur Didier Aldon Jean-Philippe Galaud 《Plant signaling & behavior》2011,6(4):538-540
The RD20 gene encodes a member of the caleosin family, which is primarily known to function in the mobilization of seed storage lipids during germination. In contrast to other caleosins, RD20 expression is early-induced by water deficit conditions and we recently provided genetic evidence for its positive role in drought tolerance in Arabidopsis. RD20 is also responsive to pathogen infection and is constitutively expressed in diverse tissues and organs during development suggesting additional roles for this caleosin. This addendum describes further exploration of phenotypic alterations in T-DNA insertional rd20 mutant and knock-out complemented transgenic plants in the context of early development and susceptibility to a phytopathogenic bacteria. We show that the RD20 gene is involved in ABA-mediated inhibition of germination and does not play a significant role in plant defense against Pseudomonas syringae.Key words: ABA, Arabidopsis thaliana, biotic stress, caleosin, germination, RD20 相似文献
102.
Makowsky R Pajewski NM Klimentidis YC Vazquez AI Duarte CW Allison DB de los Campos G 《PLoS genetics》2011,7(4):e1002051
Despite rapid advances in genomic technology, our ability to account for phenotypic variation using genetic information remains limited for many traits. This has unfortunately resulted in limited application of genetic data towards preventive and personalized medicine, one of the primary impetuses of genome-wide association studies. Recently, a large proportion of the "missing heritability" for human height was statistically explained by modeling thousands of single nucleotide polymorphisms concurrently. However, it is currently unclear how gains in explained genetic variance will translate to the prediction of yet-to-be observed phenotypes. Using data from the Framingham Heart Study, we explore the genomic prediction of human height in training and validation samples while varying the statistical approach used, the number of SNPs included in the model, the validation scheme, and the number of subjects used to train the model. In our training datasets, we are able to explain a large proportion of the variation in height (h(2) up to 0.83, R(2) up to 0.96). However, the proportion of variance accounted for in validation samples is much smaller (ranging from 0.15 to 0.36 depending on the degree of familial information used in the training dataset). While such R(2) values vastly exceed what has been previously reported using a reduced number of pre-selected markers (<0.10), given the heritability of the trait (~ 0.80), substantial room for improvement remains. 相似文献
103.
We present a single-molecule instrument that combines a time-shared ultrahigh-resolution dual optical trap interlaced with a confocal fluorescence microscope. In a demonstration experiment, we observed individual single fluorophore-labeled DNA oligonucleotides to bind and unbind complementary DNA suspended between two trapped beads. Simultaneous with the single-fluorophore detection, we clearly observed coincident angstrom-scale changes in tether extension. Fluorescence readout allowed us to determine the duplex melting rate as a function of force. The new instrument will enable the simultaneous measurement of angstrom-scale mechanical motion of individual DNA-binding proteins (for example, single-base-pair stepping of DNA translocases) along with the detection of properties of fluorescently labeled protein (for example, internal configuration). 相似文献
104.
Firn J Moore JL MacDougall AS Borer ET Seabloom EW HilleRisLambers J Harpole WS Cleland EE Brown CS Knops JM Prober SM Pyke DA Farrell KA Bakker JD O'Halloran LR Adler PB Collins SL D'Antonio CM Crawley MJ Wolkovich EM La Pierre KJ Melbourne BA Hautier Y Morgan JW Leakey AD Kay A McCulley R Davies KF Stevens CJ Chu CJ Holl KD Klein JA Fay PA Hagenah N Kirkman KP Buckley YM 《Ecology letters》2011,14(3):274-281
Many ecosystems worldwide are dominated by introduced plant species, leading to loss of biodiversity and ecosystem function. A common but rarely tested assumption is that these plants are more abundant in introduced vs. native communities, because ecological or evolutionary-based shifts in populations underlie invasion success. Here, data for 26 herbaceous species at 39 sites, within eight countries, revealed that species abundances were similar at native (home) and introduced (away) sites - grass species were generally abundant home and away, while forbs were low in abundance, but more abundant at home. Sites with six or more of these species had similar community abundance hierarchies, suggesting that suites of introduced species are assembling similarly on different continents. Overall, we found that substantial changes to populations are not necessarily a pre-condition for invasion success and that increases in species abundance are unusual. Instead, abundance at home predicts abundance away, a potentially useful additional criterion for biosecurity programmes. 相似文献
105.
Yann Gibert Sana Sassi-Messai Jean-Baptiste Fini Laure Bernard Daniel Zalko Jean-Pierre Cravedi Patrick Balaguer Monika Andersson-Lendahl Barbara Demeneix Vincent Laudet 《BMC developmental biology》2011,11(1):4
Background
The plastic monomer and plasticizer bisphenol A (BPA), used for manufacturing polycarbonate plastic and epoxy resins, is produced at over 2.5 million metric tons per year. Concerns have been raised that BPA acts as an endocrine disruptor on both developmental and reproductive processes and a large body of evidence suggests that BPA interferes with estrogen and thyroid hormone signaling. Here, we investigated BPA effects during embryonic development using the zebrafish and Xenopus models. 相似文献106.
Hajage D de Rycke Y Bollet M Savignoni A Caly M Pierga JY Horlings HM Van de Vijver MJ Vincent-Salomon A Sigal-Zafrani B Senechal C Asselain B Sastre X Reyal F 《PloS one》2011,6(11):e27446
Background
Adjuvant! Online is a web-based application designed to provide 10 years survival probability of patients with breast cancer. Several predictors have not been assessed in the original Adjuvant! Online study. We provide the validation of Adjuvant! Online algorithm on two breast cancer datasets, and we determined whether the accuracy of Adjuvant! Online is improved with other well-known prognostic factors.Patients and Methods
The French data set is composed of 456 women with early breast cancer. The Dutch data set is composed of 295 women less than 52 years of age. Agreement between observation and Adjuvant! Online prediction was checked, and logistic models were performed to estimate the prognostic information added by risk factors to Adjuvant! Online prediction.Results
Adjuvant! Online prediction was overall well-calibrated in the French data set but failed in some subgroups of such high grade and HER2 positive patients. HER2 status, Mitotic Index and Ki67 added significant information to Adjuvant! Online prediction. In the Dutch data set, the overall 10-year survival was overestimated by Adjuvant! Online, particularly in patients less than 40 years old.Conclusion
Adjuvant! Online needs to be updated to adjust overoptimistic results in young and high grade patients, and should consider new predictors such as Ki67, HER2 and Mitotic Index. 相似文献107.
108.
Choquet H Labrune Y De Graeve F Hinney A Hebebrand J Scherag A Lecoeur C Tauber M Balkau B Elliot P Jarvelin MR Walley AJ Besnard P Froguel P Meyre D 《Obesity (Silver Spring, Md.)》2011,19(4):833-839
A recent study suggested that four CD36 polymorphisms (namely rs3211867, rs3211883, rs3211908, and rs1527483) were associated with an increased risk of obesity, an increased BMI and percentage of body fat in European adolescents. We first attempted to confirm these results in three independent case-control genome-wide association studies (GWAS) data totaling 3,509 subjects of French and German origin, but we were unable to find any association of these variants with early onset obesity risk. We then genotyped the four CD36 single-nucleotide polymorphisms (SNPs) in a large population-based study of 4,667 Finnish subjects and we did not replicate any of the recently reported associations with BMI. By combining all available data in a meta-analysis (N = 9,973), we found no evidence for an association of the reported four variants in CD36 with increased obesity risk or increased BMI (0.07 ≤ P values ≤ 0.93). Finally, we assessed the contribution of the full CD36 locus gene variation to obesity risk in 3,509 subjects and we did not detect any significant association with obesity after correction for multiple testing. In summary, we were unable to confirm the recently reported association of variants in CD36 with early onset obesity in populations of European ancestry. 相似文献
109.
Voituron Y Joly P Eugène M Barré H 《American journal of physiology. Regulatory, integrative and comparative physiology》2005,288(6):R1563-R1570
Survival and some physiological responses to freezing were investigated in three European water frogs (Rana lessonae, Rana ridibunda, and their hybridogen Rana esculenta). The three species exhibited different survival times during freezing (from 10 h for R. lessonae to 20 h for R. ridibunda). The time courses of percent water frozen were similar; however, because of the huge differences in body mass among species (from 10 g for Rana lessonae to nearly 100 g for Rana ridibunda), the ice mass accumulation rate varied markedly (from 0.75 +/- 0.12 to 1.43 +/- 0.11 g ice/h, respectively) and was lowest in the terrestrial hibernator Rana lessonae. The hybrid Rana esculenta exhibited an intermediate response between the two parental species; furthermore, within-species correlation existed between body mass and ice mass accumulation rates, suggesting the occurrence of subpopulations in this species (0.84 +/- 0.08 g ice/h for small R. esculenta and 1.78 +/- 0.09 g ice/h for large ones). Biochemical analyses showed accumulation of blood glucose and lactate, liver glucose (originating from glycogen), and liver alanine in Rana lessonae and Rana esculenta but not in Rana ridibunda in response to freezing. The variation of freeze tolerance between these three closely related species could bring understanding to the physiological processes involved in the evolution of freeze tolerance in vertebrates. 相似文献