Mutagenesis of a functional chimeric gene in yeast identifies mutations in the simian virus 40 large T antigen J domain
Mutagenesis of a functional chimeric gene in yeast identifies mutations in the simian virus 40 large T antigen J domain
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DOI：
10.1073/pnas.042670999
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发表时间：
2002-02-19
影响因子：
11.1
通讯作者：
Brodsky, JL
中科院分区：
文献类型：
--
作者：
Fewell, SW;Pipas, JM;Brodsky, JL
Simian virus 40 large T antigen contains an amino terminal J domain that catalyzes T antigen-mediated viral DNA replication and cellular transformation. To dissect the role of the J domain in these processes, we exploited the genetic tools available only in the yeast Saccharomyces cerevisiae to isolate 14 loss-of-function point mutations in the T antigen J domain. This screen also identified mutations that, when engineered into simian virus 40, resulted in T antigen mutants that were defective for the ability to support viral growth, to transform mammalian cells in culture, to dissociate the p130-E2F4 transcription factor complex, and to stimulate ATP hydrolysis by hsc70, a hallmark of J domain-containing molecular chaperones. These data correlate the chaperone activity of the T antigen J domain with its roles in viral infection and cellular transformation and support a model by which the viral J domain recruits the cytoplasmic hsc70 molecular chaperone in the host to rearrange multiprotein complexes implicated in replication and transformation. More generally, this study presents the use of a yeast screen to identify loss-of-function mutations in a mammalian virus and can serve as a widely applicable method to uncover domain functions of mammalian proteins for which there are yeast homologues with selectable mutant phenotypes.
