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排序方式: 共有199条查询结果,搜索用时 15 毫秒
191.
Functional profiling of the Saccharomyces cerevisiae genome 总被引:1,自引:0,他引:1
Giaever G Chu AM Ni L Connelly C Riles L Véronneau S Dow S Lucau-Danila A Anderson K André B Arkin AP Astromoff A El-Bakkoury M Bangham R Benito R Brachat S Campanaro S Curtiss M Davis K Deutschbauer A Entian KD Flaherty P Foury F Garfinkel DJ Gerstein M Gotte D Güldener U Hegemann JH Hempel S Herman Z Jaramillo DF Kelly DE Kelly SL Kötter P LaBonte D Lamb DC Lan N Liang H Liao H Liu L Luo C Lussier M Mao R Menard P Ooi SL Revuelta JL Roberts CJ Rose M Ross-Macdonald P Scherens B Schimmack G 《Nature》2002,418(6896):387-391
Determining the effect of gene deletion is a fundamental approach to understanding gene function. Conventional genetic screens exhibit biases, and genes contributing to a phenotype are often missed. We systematically constructed a nearly complete collection of gene-deletion mutants (96% of annotated open reading frames, or ORFs) of the yeast Saccharomyces cerevisiae. DNA sequences dubbed 'molecular bar codes' uniquely identify each strain, enabling their growth to be analysed in parallel and the fitness contribution of each gene to be quantitatively assessed by hybridization to high-density oligonucleotide arrays. We show that previously known and new genes are necessary for optimal growth under six well-studied conditions: high salt, sorbitol, galactose, pH 8, minimal medium and nystatin treatment. Less than 7% of genes that exhibit a significant increase in messenger RNA expression are also required for optimal growth in four of the tested conditions. Our results validate the yeast gene-deletion collection as a valuable resource for functional genomics. 相似文献
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Horizontal gene transfer--the exchange of genes across mating barriers--is recognized as a major force in bacterial evolution. However, in eukaryotes it is prevalent only in certain phagotrophic protists and limited largely to the ancient acquisition of bacterial genes. Although the human genome was initially reported to contain over 100 genes acquired during vertebrate evolution from bacteria, this claim was immediately and repeatedly rebutted. Moreover, horizontal transfer is unknown within the evolution of animals, plants and fungi except in the special context of mobile genetic elements. Here we show, however, that standard mitochondrial genes, encoding ribosomal and respiratory proteins, are subject to evolutionarily frequent horizontal transfer between distantly related flowering plants. These transfers have created a variety of genomic outcomes, including gene duplication, recapture of genes lost through transfer to the nucleus, and chimaeric, half-monocot, half-dicot genes. These results imply the existence of mechanisms for the delivery of DNA between unrelated plants, indicate that horizontal transfer is also a force in plant nuclear genomes, and are discussed in the contexts of plant molecular phylogeny and genetically modified plants. 相似文献
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Atlas R Campbell P Cozzarelli NR Curfman G Enquist L Fink G Flanagin A Fletcher J George E Hammes G Heyman D Inglesby T Kaplan S Kennedy D Krug J Levinson R Marcus E Metzger H Morse SS O'Brien A Onderdonk A Poste G Renault B Rich R Rosengard A Salzberg S Scanlan M Shenk T Tabor H Varmus H Wimmer E Yamamoto K;Journal Editors Authors Group 《Nature》2003,421(6925):771
196.
Plankton effect on cod recruitment in the North Sea 总被引:2,自引:0,他引:2
The Atlantic cod (Gadus morhua L.) has been overexploited in the North Sea since the late 1960s and great concern has been expressed about the decline in cod biomass and recruitment. Here we show that, in addition to the effects of overfishing, fluctuations in plankton have resulted in long-term changes in cod recruitment in the North Sea (bottom-up control). Survival of larval cod is shown to depend on three key biological parameters of their prey: the mean size of prey, seasonal timing and abundance. We suggest a mechanism, involving the match/mismatch hypothesis, by which variability in temperature affects larval cod survival and conclude that rising temperature since the mid-1980s has modified the plankton ecosystem in a way that reduces the survival of young cod. 相似文献
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