An essential function of a phosphoinositide-specific phospholipase C is relieved by inhibition of a cyclin-dependent protein kinase in the yeast Saccharomyces cerevisiae.
An essential function of a phosphoinositide-specific phospholipase C is relieved by inhibition of a cyclin-dependent protein kinase in the yeast Saccharomyces cerevisiae.
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通过抑制酿酒酵母中的细胞周期蛋白依赖性蛋白激酶，可以减轻磷酸肌醇特异性磷脂酶 C 的基本功能。
DOI：
10.1093/genetics/148.1.33
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发表时间：
1998
期刊：
影响因子：
3.3
通讯作者：
Thorner,J
中科院分区：
文献类型：
--
作者：
Flick,JS;Thorner,J
酿酒酵母的 PLC1 基因产物是哺乳动物磷酸肌醇特异性磷脂酶 C (PI-PLC) δ 亚型的同源物。我们发现两个基因（SPL1 和 SPL2）在过度表达时可以绕过 plc1Δ 细胞的温度敏感生长缺陷。 SPL1 与 PHO81 基因相同，后者编码细胞周期蛋白 (Pho80p) 依赖性蛋白激酶 (Pho85p) 复合物 (Cdk) 的抑制剂。除了 Pho81p 的过量产生之外，使该 Cdk 失活的另外两个条件，即细胞周期蛋白 (pho80Δ) 突变和在低磷酸盐培养基上的生长，也允许 plc1Δ 细胞在限制温度下生长。 pho80Δ 对 plc1Δ 细胞温度敏感性的抑制不依赖于 Pho4p 转录调节因子，Pho4p 是 Pho80p/Pho85p Cdk 唯一已知的底物。第二个抑制因子 SPL2 编码一种小 (17 kD) 蛋白质，该蛋白质与 Pho81p 和其他已知 Cdk 抑制剂中存在的锚蛋白重复区域相似。 pho81Δ 和 spl2Δ 均显示出与 plc1Δ 组合的合成表型。与单突变体不同，plc1Δ pho81Δ 和 plc1Δ spl2Δ 双突变体无法在合成完全培养基上生长，但能够在丰富培养基上生长。
The PLC1 gene product of Saccharomyces cerevisiae is a homolog of the δ isoform of mammalian phosphoinositide-specific phospholipase C (PI-PLC). We found that two genes (SPL1 and SPL2), when overexpressed, can bypass the temperature-sensitive growth defect of a plc1Δ cell. SPL1 is identical to the PHO81 gene, which encodes an inhibitor of a cyclin (Pho80p)-dependent protein kinase (Pho85p) complex (Cdk). In addition to overproduction of Pho81p, two other conditions that inactivate this Cdk, a cyclin (pho80Δ) mutation and growth on low-phosphate medium, also permitted growth of plc1Δ cells at the restrictive temperature. Suppression of the temperature sensitivity of plc1Δ cells by pho80Δ does not depend upon the Pho4p transcriptional regulator, the only known substrate of the Pho80p/Pho85p Cdk. The second suppressor, SPL2, encodes a small (17-kD) protein that bears similarity to the ankyrin repeat regions present in Pho81p and in other known Cdk inhibitors. Both pho81Δ and spl2Δ show a synthetic phenotype in combination with plc1Δ. Unlike single mutants, plc1Δ pho81Δ and plc1Δ spl2Δ double mutants were unable to grow on synthetic complete medium, but were able to grow on rich medium.