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91.
The genome of the extremophile crucifer Thellungiella parvula 总被引:1,自引:0,他引:1
Dassanayake M Oh DH Haas JS Hernandez A Hong H Ali S Yun DJ Bressan RA Zhu JK Bohnert HJ Cheeseman JM 《Nature genetics》2011,43(9):913-918
Thellungiella parvula is related to Arabidopsis thaliana and is endemic to saline, resource-poor habitats, making it a model for the evolution of plant adaptation to extreme environments. Here we present the draft genome for this extremophile species. Exclusively by next generation sequencing, we obtained the de novo assembled genome in 1,496 gap-free contigs, closely approximating the estimated genome size of 140 Mb. We anchored these contigs to seven pseudo chromosomes without the use of maps. We show that short reads can be assembled to a near-complete chromosome level for a eukaryotic species lacking prior genetic information. The sequence identifies a number of tandem duplications that, by the nature of the duplicated genes, suggest a possible basis for T. parvula's extremophile lifestyle. Our results provide essential background for developing genomically influenced testable hypotheses for the evolution of environmental stress tolerance. 相似文献
92.
Giardine B Borg J Higgs DR Peterson KR Philipsen S Maglott D Singleton BK Anstee DJ Basak AN Clark B Costa FC Faustino P Fedosyuk H Felice AE Francina A Galanello R Gallivan MV Georgitsi M Gibbons RJ Giordano PC Harteveld CL Hoyer JD Jarvis M Joly P Kanavakis E Kollia P Menzel S Miller W Moradkhani K Old J Papachatzopoulou A Papadakis MN Papadopoulos P Pavlovic S Perseu L Radmilovic M Riemer C Satta S Schrijver I Stojiljkovic M Thein SL Traeger-Synodinos J Tully R Wada T Waye JS Wiemann C 《Nature genetics》2011,43(4):295-301
We developed a series of interrelated locus-specific databases to store all published and unpublished genetic variation related to hemoglobinopathies and thalassemia and implemented microattribution to encourage submission of unpublished observations of genetic variation to these public repositories. A total of 1,941 unique genetic variants in 37 genes, encoding globins and other erythroid proteins, are currently documented in these databases, with reciprocal attribution of microcitations to data contributors. Our project provides the first example of implementing microattribution to incentivise submission of all known genetic variation in a defined system. It has demonstrably increased the reporting of human variants, leading to a comprehensive online resource for systematically describing human genetic variation in the globin genes and other genes contributing to hemoglobinopathies and thalassemias. The principles established here will serve as a model for other systems and for the analysis of other common and/or complex human genetic diseases. 相似文献
93.
Common variants at MS4A4/MS4A6E, CD2AP, CD33 and EPHA1 are associated with late-onset Alzheimer's disease 总被引:1,自引:0,他引:1
Naj AC Jun G Beecham GW Wang LS Vardarajan BN Buros J Gallins PJ Buxbaum JD Jarvik GP Crane PK Larson EB Bird TD Boeve BF Graff-Radford NR De Jager PL Evans D Schneider JA Carrasquillo MM Ertekin-Taner N Younkin SG Cruchaga C Kauwe JS Nowotny P Kramer P Hardy J Huentelman MJ Myers AJ Barmada MM Demirci FY Baldwin CT Green RC Rogaeva E St George-Hyslop P Arnold SE Barber R Beach T Bigio EH Bowen JD Boxer A Burke JR Cairns NJ Carlson CS Carney RM Carroll SL Chui HC Clark DG Corneveaux J Cotman CW 《Nature genetics》2011,43(5):436-441
The Alzheimer Disease Genetics Consortium (ADGC) performed a genome-wide association study of late-onset Alzheimer disease using a three-stage design consisting of a discovery stage (stage 1) and two replication stages (stages 2 and 3). Both joint analysis and meta-analysis approaches were used. We obtained genome-wide significant results at MS4A4A (rs4938933; stages 1 and 2, meta-analysis P (P(M)) = 1.7 × 10(-9), joint analysis P (P(J)) = 1.7 × 10(-9); stages 1, 2 and 3, P(M) = 8.2 × 10(-12)), CD2AP (rs9349407; stages 1, 2 and 3, P(M) = 8.6 × 10(-9)), EPHA1 (rs11767557; stages 1, 2 and 3, P(M) = 6.0 × 10(-10)) and CD33 (rs3865444; stages 1, 2 and 3, P(M) = 1.6 × 10(-9)). We also replicated previous associations at CR1 (rs6701713; P(M) = 4.6 × 10(-10), P(J) = 5.2 × 10(-11)), CLU (rs1532278; P(M) = 8.3 × 10(-8), P(J) = 1.9 × 10(-8)), BIN1 (rs7561528; P(M) = 4.0 × 10(-14), P(J) = 5.2 × 10(-14)) and PICALM (rs561655; P(M) = 7.0 × 10(-11), P(J) = 1.0 × 10(-10)), but not at EXOC3L2, to late-onset Alzheimer's disease susceptibility. 相似文献
94.
Burdon KP Macgregor S Hewitt AW Sharma S Chidlow G Mills RA Danoy P Casson R Viswanathan AC Liu JZ Landers J Henders AK Wood J Souzeau E Crawford A Leo P Wang JJ Rochtchina E Nyholt DR Martin NG Montgomery GW Mitchell P Brown MA Mackey DA Craig JE 《Nature genetics》2011,43(6):574-578
We report a genome-wide association study for open-angle glaucoma (OAG) blindness using a discovery cohort of 590 individuals with severe visual field loss (cases) and 3,956 controls. We identified associated loci at TMCO1 (rs4656461[G] odds ratio (OR) = 1.68, P = 6.1 × 10(-10)) and CDKN2B-AS1 (rs4977756[A] OR = 1.50, P = 4.7 × 10(-9)). We replicated these associations in an independent cohort of cases with advanced OAG (rs4656461 P = 0.010; rs4977756 P = 0.042) and two additional cohorts of less severe OAG (rs4656461 combined discovery and replication P = 6.00 × 10(-14), OR = 1.51, 95% CI 1.35-1.68; rs4977756 combined P = 1.35 × 10(-14), OR = 1.39, 95% CI 1.28-1.51). We show retinal expression of genes at both loci in human ocular tissues. We also show that CDKN2A and CDKN2B are upregulated in the retina of a rat model of glaucoma. 相似文献
95.
Translation initiation is a critical step in protein synthesis. Previously, two major mechanisms of initiation were considered
as essential: prokaryotic, based on SD interaction; and eukaryotic, requiring cap structure and ribosomal scanning. Although
discovered decades ago, cap-independent translation has recently been acknowledged as a widely spread mechanism in viruses,
which may take place in some cellular mRNA translations. Moreover, it has become evident that translation can be initiated
on the leaderless mRNA in all three domains of life. New findings demonstrate that other distinguishable types of initiation
exist, including SD-independent in Bacteria and Archaea, and various modifications of 5′ end-dependent and internal initiation
mechanisms in Eukarya. Since translation initiation has developed through the loss, acquisition, and modification of functional
elements, all of which have been elevated by competition with viral translation in a large number of organisms of different
complexity, more variation in initiation mechanisms can be anticipated. 相似文献
96.
Oleksiewicz U Liloglou T Field JK Xinarianos G 《Cellular and molecular life sciences : CMLS》2011,68(23):3869-3883
Since the discovery of cytoglobin (Cygb) a decade ago, growing amounts of data have been gathered to characterise Cygb biochemistry,
functioning and implication in human pathologies. Its molecular roles remain under investigation, but nitric oxide dioxygenase
and lipid peroxidase activities have been demonstrated. Cygb expression increases in response to various stress conditions
including hypoxia, oxidative stress and fibrotic stimulation. When exogenously overexpressed, Cygb revealed cytoprotection
against these factors. Cygb was shown to be upregulated in fibrosis and neurodegenerative disorders and downregulated in multiple
cancer types. CYGB was also found within the minimal region of a hereditary tylosis with oesophageal cancer syndrome, and its expression was
reduced in tylotic samples. Recently, Cygb has been shown to inhibit cancer cell growth in vitro, thus confirming its suggested
tumour suppressor role. This article aims to review the biochemical and functional aspects of Cygb, its involvement in various
pathological conditions and potential clinical utility. 相似文献
97.
Stephen Richard Alfred John Timothy Lambert Jr 《Systemic Practice and Action Research》2012,25(4):323-354
This is an exploratory case study of a management issue that confronts filmmakers: how do they select locations for their films? The outcome of those decisions can have vast and immediate effects upon the profitability of a film. This is a sometimes shadowy, but significant industry with a major economic impact. For systems theory advocates, students, and explorers, this study demonstrates that investigative, immersive action research techniques can be used to explore what are otherwise hidden, somewhat cloistered business organizations and industry structures that are ordinarily closed to outsiders. The soft-system of this industry that is rooted upon trust, loyalty, alliances, relationships, and other non-financial bonds influence its decisions, and its institutional performance. While this research is focused upon a fragment of the overall film industry worldwide, and is thus limited in the universality of the propositions that subsequently emerge, this study can serve as a springboard for research into other soft systems, from which new knowledge of managerial perspectives can emerge. 相似文献
98.
我们以Morwell和Coolungoolun两种维多利亚褐煤进行实验,对铁和锡在煤的液化中的催化作用进行了比较,发现锡对低硫的Morwell煤较为有效,而铁则更适合于高硫的Coolungoolun煤。对液化余渣的穆斯堡尔分析的结果,使我们可以用低硫煤中元素态锡的形成以及在高硫煤中磁黄铁矿(Fe_(0.92)S)的形成来对观察到的现象作出解释。硫的损耗数据表明,磁黄铁矿的存在使得煤中的硫转化为气相的量增加了。 相似文献
99.
There is a powerful market-need for superfast disperse dyes in special use, e.g. for automotivefabrics. The photochemical fading reactions of dyes are often very complicated, and no singlphotodegradation pathway can be involved for all kinds of dyes. To enhance the photostability of the commonly used disperse dyes, a series of tests on the ef-fect of variable stabilizers on the photodegradation rate of nine representative disperse dyes werecarried out both in ethyl acetate solution and on cellulose acetate film. A moderate light sourceemitting above 300 nm was adopted in this study to simulate the photofading under practical appli-cations. The results show that, in solution, 2,2,6,6-tetramethyl-piperidine is the most effectivegeneral stabilizer for all the tested dyes, but on cellulose film, nickel diethyl-dithiocarbamateshows the greatest general protecting effect, and a synergistic effect is observed for special combina-tions of stabilizers. 相似文献
100.
N E Simpson K K Kidd P J Goodfellow H McDermid S Myers J R Kidd C E Jackson A M Duncan L A Farrer K Brasch 《Nature》1987,328(6130):528-530
Multiple endocrine neoplasis type 2A (MEN2A) is one of several kinds of cancers that appear to be inherited in an autosomally dominant fashion. We have assigned the MEN2A locus to chromosome 10 by linkage with a new DNA marker (D10S5). The linkage led us to investigate other chromosome 10 markers and demonstrate linkage between the disease locus and the interstitial retinol-binding protein (IRBP) gene. The D10S5 locus was sublocalized to 10q21.1 by hybridization in situ and the IRBP gene to p11.2----q11.2 with a secondary site at q24----q25. The linkages were established using 292 members of five families, three different restriction fragment length polymorphisms (RFLPs) at D10S5 and two RFLPs recognized by the IRBP probe. The recombination frequencies from pairwise linkage analysis between the disease and two marker loci D10S5 and IRBP were 0.19 and 0.11, with maximum lod scores of 3.6 and 8.0 respectively. Ordering of the three loci by multipoint analysis placed the IRBP gene approximately midway between the disease and D10S5 loci. 相似文献