Stephen D W, Rivers S L, Jamieson D J
Biomedical Research Centre, Ninewells Hospital, Dundee, UK.
Mol Microbiol. 1995 May;16(3):415-23. doi: 10.1111/j.1365-2958.1995.tb02407.x.
The YAP1 and YAP2 genes encode yeast transcription factors of the c-jun family. We show that yeast mutants deleted for either the YAP1 or the YAP2 genes are hypersensitive to oxidants, particularly H2O2, and that these genes play a role in regulating the induction of the H2O2 adaptive stress response in Saccharomyces cerevisiae. They do not significantly affect the regulation of the superoxide adaptive stress response. The intrinsic resistance of stationary-phase and respiring yeast cells towards superoxide anions is unaffected by deletion of the YAP1 and YAP2 genes. However, resistance towards H2O2 under these conditions is significantly reduced. We show that expression of the yeast GSH1 gene (encoding gamma-glutamylcysteine synthetase) and the SSA1 gene (encoding an HSP70 isoform) are induced by oxidants. Unlike the SSA1 and thioredoxin (TRX2) genes, expression of the GSH1 gene is more strongly induced by superoxide anions than by H2O2. In the absence of added oxidants, transcription of the GSH1 gene is reduced in strains carrying the yap1 deletion. However, we show that Yap1 is not required for the superoxide anion-mediated induction of GSH1 gene expression. Furthermore, while the H2O2-mediated induction of SSA1 expression is shown to by YAP1 dependent, the heat-shock-mediated induction of the SSA1 gene does not require YAP1. We also present evidence to show that the YAP2 gene does not regulate the expression of the TRX2, SSA1 or GSH1 genes.
YAP1和YAP2基因编码c-jun家族的酵母转录因子。我们发现，缺失YAP1或YAP2基因的酵母突变体对氧化剂，尤其是H2O2高度敏感，并且这些基因在调节酿酒酵母中H2O2适应性应激反应的诱导中发挥作用。它们对超氧化物适应性应激反应的调节没有显著影响。静止期和呼吸型酵母细胞对超氧阴离子的固有抗性不受YAP1和YAP2基因缺失的影响。然而，在这些条件下对H2O2的抗性显著降低。我们发现，酵母GSH1基因（编码γ-谷氨酰半胱氨酸合成酶）和SSA1基因（编码一种HSP70亚型）的表达受氧化剂诱导。与SSA1和硫氧还蛋白（TRX2）基因不同，GSH1基因的表达受超氧阴离子诱导的程度比受H2O2诱导的程度更强。在没有添加氧化剂的情况下，携带yap1缺失的菌株中GSH1基因的转录减少。然而，我们发现Yap1不是超氧阴离子介导的GSH1基因表达诱导所必需的。此外，虽然H2O2介导的SSA1表达诱导显示依赖于YAP1，但热休克介导的SSA1基因诱导不需要YAP1。我们还提供证据表明，YAP2基因不调节TRX2、SSA1或GSH1基因的表达。
