Coordination mechanisms of stress response with cell cycle regulation by the yeast Pho85 kinase

当酵母细胞遇到环境压力时，细胞周期的进展被延迟，为适应压力条件提供了时间。我们发现CLN 2在碱性条件下下调，并且需要Pho 85-Pho 80复合物来维持CLN 2在碱性条件下的表达。我们还发现，Pho 4是必要的适应碱性条件，可能通过激活Ptk 2。碱性胁迫信号通过Pho 81 CKI传递以抑制Pho 85-Pho 80活性，这导致转录因子Pho 4、Rim 101和Crz 1的激活，所有这些转录因子在过量产生时抑制CLN 2表达。Whi 5抑制CLN 2表达，并且当Whi 5活性被过量产生的Pho 85-Pcl 9抑制时，pho 85 pho 4 rim 101 crz 1四重缺失突变体中的CLN 2表达水平被刺激。Rpd 3参与这些因子对CLN 2的抑制。

When yeast cells encounter environmental stress, progression through the cell cycle is delayed, providing time for adaptation to the stress conditions. We found that CLN2 was downregulated under alkaline conditions, and that the Pho85-Pho80 complex was required to sustain CLN2 expression under alkaline conditions. We also found that Pho4 is necessary for adaptation to alkaline conditions, possibly by activating Ptk2. The alkaline stress signal was transmitted through Pho81 CKI to repress the Pho85-Pho80 activity, which leads to activation of transcription factors Pho4, Rim101, and Crz1, all of which inhibited CLN2 expression when overproduced. Whi5 represses CLN2 expression, and CLN2 expression level in a pho85 pho4 rim101 crz1 quadruple deletion mutant was stimulated when the Whi5 activity was repressed by overproduction of Pho85-Pcl9. Rpd3 is involved in CLN2 repression by these factors.