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131.
Florian Villegas Daphné Lehalle Daniela Mayer Melanie Rittirsch Michael B. Stadler Marietta Zinner Daniel Olivieri Pierre Vabres Laurence Duplomb-Jego Eveline S.J.M. De Bont Yannis Duffourd Floor Duijkers Magali Avila David Geneviève Nada Houcinat Thibaud Jouan Paul Kuentz Klaske D. Lichtenbelt Joerg Betschinger 《Cell Stem Cell》2019,24(2):257-270.e8
132.
Obesity in Adolescence Predicts Lower Educational Attainment and Income in Adulthood: The Project EAT Longitudinal Study 下载免费PDF全文
Simone A. French Melanie Wall Thomas Corbeil Nancy E. Sherwood Jerica M. Berge Dianne Neumark‐Sztainer 《Obesity (Silver Spring, Md.)》2018,26(9):1467-1473
Objective
Prospective associations between obesity in adolescence and adult socioeconomic outcomes, and potential mediators, were examined in a contemporary cohort.Methods
Longitudinal data collected in 1998 to 1999 (Project EAT‐I) and 2015 to 2016 (EAT‐IV) were analyzed for 1,796 participants who provided data at both time points. Adolescents (mean age = 14.8 years) self‐reported demographic and psychosocial variables (EAT‐I) and follow‐up outcomes (EAT‐IV). Body weight and height were directly measured. Bachelor's degree or more education, income ≥ US $50,000, and partnered status at follow‐up were examined by baseline obesity (>95th BMI percentile) using logistic regression. Self‐esteem, depression, and weight‐related teasing were examined as mediators using multivariate probit regressions. All analyses were adjusted for race, baseline age, and parent socioeconomic status.Results
Girls with obesity were significantly less likely to have achieved a bachelor’s degree (OR 0.32, 95% CI [0.18, 0.58]; P < 0.001), earn ≥ $50,000 annually (OR 0.57, 95% CI [0.33, 0.99]; P < 0.04), or be partnered (OR 0.45, 95% CI [0.27, 0.75]; P < 0.002) in adulthood. No associations were observed among boys. Among girls, depression mediated 8.5% and 23.6% of the association between adolescent obesity and adult education and income, respectively.Conclusions
Adolescent girls with obesity have lower educational attainment and income and are less likely to be partnered in later adulthood. Depression may partly mediate the associations.133.
Susan Strome James Powers Melanie Dunn Kimberly Reese Christian J. Malone John White Geraldine Seydoux William Saxton 《Molecular biology of the cell》2001,12(6):1751-1764
gamma-Tubulin is a ubiquitous and highly conserved component of centrosomes in eukaryotic cells. Genetic and biochemical studies have demonstrated that gamma-tubulin functions as part of a complex to nucleate microtubule polymerization from centrosomes. We show that, as in other organisms, Caenorhabditis elegans gamma-tubulin is concentrated in centrosomes. To study centrosome dynamics in embryos, we generated transgenic worms that express GFP::gamma-tubulin or GFP::beta-tubulin in the maternal germ line and early embryos. Multiphoton microscopy of embryos produced by these worms revealed the time course of daughter centrosome appearance and growth and the differential behavior of centrosomes destined for germ line and somatic blastomeres. To study the role of gamma-tubulin in nucleation and organization of spindle microtubules, we used RNA interference (RNAi) to deplete C. elegans embryos of gamma-tubulin. gamma-Tubulin (RNAi) embryos failed in chromosome segregation, but surprisingly, they contained extensive microtubule arrays. Moderately affected embryos contained bipolar spindles with dense and long astral microtubule arrays but with poorly organized kinetochore and interpolar microtubules. Severely affected embryos contained collapsed spindles with numerous long astral microtubules. Our results suggest that gamma-tubulin is not absolutely required for microtubule nucleation in C. elegans but is required for the normal organization and function of kinetochore and interpolar microtubules. 相似文献
134.
Sze Chern Lim Katherine R. Smith David A. Stroud Alison G. Compton Elena J. Tucker Ayan Dasvarma Luke C. Gandolfo Justine E. Marum Matthew McKenzie Heidi L. Peters David Mowat Peter G. Procopis Bridget Wilcken John Christodoulou Garry K. Brown Michael T. Ryan Melanie Bahlo David R. Thorburn 《American journal of human genetics》2014
135.
136.
Nora M. Casey Dan Milbourne Susanne Barth Melanie Febrer Glyn Jenkins Michael T. Abberton Charlotte Jones Daniel Thorogood 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2010,121(3):567-576
White clover (Trifolium repens L.) is a forage legume of considerable economic importance in temperate agricultural systems. It has a strong self-incompatibility
system. The molecular basis of self-incompatibility in T. repens is unknown, but it is under the control of a single locus, which is expressed gametophytically. To locate the self-incompatibility
locus (S locus) in T. repens, we carried out cross-pollination experiments in an F1 mapping population and constructed a genetic linkage map using amplified fragment length polymorphism and simple sequence
repeat markers. As the first step in a map-based cloning strategy, we locate for the first time the S locus in T. repens on a genetic linkage map, on the homoeologous linkage group pair 1 (E), which is broadly syntenic to Medicago truncatula L. chromosome 1. On the basis of this syntenic relationship, the possibility that the S locus may or may not possess an S-RNase gene is discussed. 相似文献
137.
Abstract. The contribution of resprouts and seedling recruitment to post-fire regeneration of the South African fynbos conifer Widdringtonia nodiflora was compared eight months after wildfires in 1990. Stems on all trees were killed by fire but resprouting success was > 90 % at all but one site. A demographic study of burned skeletons revealed that prior to these fires, nearly all plants were multi-stemmed (4–9 stems/plant) and multi-aged, indicating continuous sprout production between fires. All stems were killed by these 1990 fires and at most sites > 90 % of the stems were burned to ground level. All diameter stems were susceptible to such incineration as, at most sites, there was no difference in average diameter of stems burned to ground level and those left standing. Individual genets usually had all ramets incinerated to ground level or all ramets charred, but intact, suggesting certain micro-sites burned hotter, whereas other sites were somewhat protected. Although not true of the 1990 fires, there was evidence that occasionally Widdring-tonia stems may survive fire. At one site, four of the 16 plants sampled had a burned stem twice as old as the oldest burned stem on the other 12 plants at the site, suggesting some stems had survived the previous fire (ca. 1970) and this conclusion was supported by fire-scars on these four stems that dated to ca. 1970. Based on the highly significant correlation between stem diameter and cone density left standing after the 1990 fires, we calculated that for most sites > 80 % of the initial cone crop was incinerated by fire. This is important because we observed a strong relationship between size of the canopy cone crop surviving fire and post-fire seedling recruitment. Under these conditions we hypothesize that sprouting confers a selective advantage to genets when fires cause heavy losses of seed. The infrequent occurrence of sprouting in the Cupressaceae suggests the hypothesis that resprouting is an apomorphic or derived trait in Widdringtonia. Data from this study suggests resprouting provides a selective advantage under severe fynbos fires, which are not only 'stand-replacing fires,’but also are intense enough to incinerate cone-bearing stems. 相似文献
138.
The N-terminal extension of cardiac troponin I (TnI) is bisphosphorylated by protein kinase A in response to beta-adrenergic stimulation. How this signal is transmitted between TnI and troponin C (TnC), resulting in accelerated Ca(2+) release, remains unclear. We recently proposed that the unphosphorylated extension interacts with the N-terminal domain of TnC stabilizing Ca(2+) binding and that phosphorylation prevents this interaction. We now use (1)H NMR to study the interactions between several N-terminal fragments of TnI, residues 1-18 (I1-18), residues 1-29 (I1-29), and residues 1-64 (I1-64), and TnC. The shorter fragments provide unambiguous information on the N-terminal regions of TnI that interact with TnC: I1-18 does not bind to TnC whereas the C-terminal region of unphosphorylated I1-29 does bind. Bisphosphorylation greatly weakens this interaction. I1-64 contains the phosphorylatable N-terminal extension and a region that anchors I1-64 to the C-terminal domain of TnC. I1-64 binding to TnC influences NMR signals arising from both domains of TnC, providing evidence that the N-terminal extension of TnI interacts with the N-terminal domain of TnC. TnC binding to I1-64 broadens NMR signals from the side chains of residues immediately C-terminal to the phosphorylation sites. Binding of TnC to bisphosphorylated I1-64 does not broaden these NMR signals to the same extent. Circular dichroism spectra of I1-64 indicate that bisphosphorylation does not produce major secondary structure changes in I1-64. We conclude that bisphosphorylation of cardiac TnI elicits its effects by weakening the interaction between the region of TnI immediately C-terminal to the phosphorylation sites and TnC either directly, due to electrostatic repulsion, or via localized conformational changes. 相似文献
139.
Mark Williams Melanie J. Leng Michael H. Stephenson Julian E. Andrews Ian P. Wilkinson David J. Siveter David J. Horne Jean M.C. Vannier 《Palaeogeography, Palaeoclimatology, Palaeoecology》2006,230(3-4):299-318
A study of the stable isotope composition (δ18O, δ13C) of biogenic (ostracod, mollusc) and authigenic carbonates in the Ballagan Formation, Lower Carboniferous of Scotland, coupled with evidence from sedimentology and associated fossil fauna and flora, supports the argument that this formation was deposited in a coastal flood plain setting, in brackish (0.5 < 30‰ NaCl) and hypersaline (> 40‰ NaCl) waters, but in the absence of persistent normal marine conditions. The oxygen isotope data from the Ballagan Formation divide into three clusters: a diagenetic field defined by low δ18O (< − 11‰ VPDB); an intermediary field (δ18O − 11‰ to − 9‰) composed of a mixture of known primary and secondary (diagenetic) carbonates; and samples within the range of − 9‰ to − 4‰ which, as far as we can ascertain, are largely unaltered. No samples give typical Early Carboniferous δ18O marine values. Average marine carbonates from Europe have δ18O between − 4‰ to − 3‰. The Ballagan Formation carbonates were probably deposited in evaporated freshwater and/or brackish water. This conclusion is supported by the presence of evaporites (gypsum, anhydrite, halite pseudomorphs) and common desiccation-cracked mudstone surfaces throughout the Ballagan Formation, suggesting conditions of fluctuating salinity in ephemeral bodies of water. The stable isotope data support the notion that the ostracod assemblages of the Ballagan Formation were colonising brackish water and hypersaline ecologies on a coastal flood plain during the Early Carboniferous, a stage of development that may have encouraged their colonisation of fully non-marine (limnetic) environments during the later Carboniferous. The ostracods include cytherellacean and kloedenellacean species known from marginal marine sites elsewhere, but probably tolerant of brackish water, podocopid species such as ‘Bythocypris’ aequalis that may have been adapted for brackish water settings on coastal flood plains (ephemeral lakes and lagoons), and paraparchitacean-dominated assemblages that may signal harsh (hypersaline or desiccating) environments. 相似文献
140.
Funes M Miller JK Lai C Carraway KL Sweeney C 《The Journal of biological chemistry》2006,281(28):19310-19319
Mucins provide a protective barrier for epithelial surfaces, and their overexpression in tumors has been implicated in malignancy. We have previously demonstrated that Muc4, a transmembrane mucin that promotes tumor growth and metastasis, physically interacts with the ErbB2 receptor tyrosine kinase and augments receptor tyrosine phosphorylation in response to the neuregulin-1beta (NRG1beta) growth factor. In the present study we demonstrate that Muc4 expression in A375 human melanoma cells, as well as MCF7 and T47D human breast cancer cells, enhances NRG1beta signaling through the phosphatidylinositol 3-kinase pathway. In examining the mechanism underlying Muc4-potentiated ErbB2 signaling, we found that Muc4 expression markedly augments NRG1beta binding to A375 cells without altering the total quantity of receptors expressed by the cells. Cell-surface protein biotinylation experiments and immunofluorescence studies suggest that Muc4 induces the relocalization of the ErbB2 and ErbB3 receptors from intracellular compartments to the plasma membrane. Moreover, Muc4 interferes with the accumulation of surface receptors within internal compartments following NRG1beta treatment by suppressing the efficiency of receptor internalization. These observations suggest that transmembrane mucins can modulate receptor tyrosine kinase signaling by influencing receptor localization and trafficking and contribute to our understanding of the mechanisms by which mucins contribute to tumor growth and progression. 相似文献