دورية أكاديمية

Genome-wide RNAi screening identifies protein damage as a regulator of osmoprotective gene expression.

التفاصيل البيبلوغرافية
العنوان: Genome-wide RNAi screening identifies protein damage as a regulator of osmoprotective gene expression.
المؤلفون: Lamitina, Todd1,2,3, Huang, Chunyi George4, Strange, Kevin1 kevin.strange@vanderbilt.edu
المصدر: Proceedings of the National Academy of Sciences of the United States of America. 8/8/2006, Vol. 103 Issue 32, p12173-12178. 6p. 1 Diagram, 1 Chart, 3 Graphs.
مصطلحات موضوعية: *RNA, *PROTEIN folding, *GENE expression, *GENETIC regulation, *PROTEIN conformation, *PHYSIOLOGICAL control systems, *HEREDITY
مستخلص: The detection, stabilization, and repair of stress-induced damage are essential requirements for cellular life. All cells respond to osmotic stress-induced water loss with increased expression of genes that mediate accumulation of organic osmolytes, solutes that function as chemical chaperones and restore osmotic homeostasis. The signals and signaling mechanisms that regulate osmoprotective gene expression in animal cells are poorly understood. Here, we show that gpdh-1 and gpdh-2, genes that mediate the accumulation of the organic osmolyte glycerol, are essential for survival of the nematode Caenorhabditis elegans during osmotic stress. Expression of GFP driven by the gpdh-1 promoter (Pgpdh-1::GFP) is detected only during hypertonic stress but is not induced by other stressors. Using Pgpdh-1:GFP expression as a phenotype, we screened ≈16,000 genes by RNAi feeding and identified 122 that cause constitutive activation of gpdh-1 expression and glycerol accumulation. Many of these genes function to regulate protein translation and cotranslational protein folding and to target and degrade denatured proteins, suggesting that the accumulation of misfolded proteins functions as a signal to activate osmoprotective gene expression and organic osmolyte accumulation in animal cells. Consistent with this hypothesis, 73% of these protein-homeostasis genes have been shown to slow age-dependent protein aggregation in C. elegans. Because diverse environmental stressors and numerous disease states result in protein misfolding, mechanisms must exist that discriminate between osmotically induced and other forms of stress-induced protein damage. Our findings provide a foundation for understanding how these damage-selectivity mechanisms function. [ABSTRACT FROM AUTHOR]
قاعدة البيانات: Academic Search Index
الوصف
تدمد:00278424
DOI:10.1073/pnas.0602987103