Paravicini G, Cooper M, Friedli L, Smith D J, Carpentier J L, Klig L S, Payton M A
GLAXO Institute for Molecular Biology, Geneva, Switzerland.
Mol Cell Biol. 1992 Nov;12(11):4896-905. doi: 10.1128/mcb.12.11.4896-4905.1992.
Seven temperature-sensitive cell lysis (cly) mutant strains of Saccharomyces cerevisiae were isolated which lyse at the restrictive temperature on hypotonic but not on osmotically supported medium. The seven mutants fell into four complementation groups, CLY12 to CLY15. The wild-type CLY15 gene was isolated by complementation of the cly15 temperature-sensitive growth defect. Sequence analysis revealed that the complementing DNA fragment encoded a partial PKC1 gene, which has previously been isolated as an S. cerevisiae homolog of mammalian protein kinase C genes (D. E. Levin, F. O. Fields, R. Kunisawa, J. M. Bishop, and J. Thorner, Cell 62:213-224, 1990). Subsequent genetic analysis showed that CLY15 and PKC1 represent identical loci in the yeast genome. A truncated PKC1 gene encoding only the predicted catalytic domain of Pkc1p was able to complement pkc1 mutant strains. Similar to what has been reported recently (D. E. Levin and E. Bartlett-Heubusch, J. Cell Biol. 116:1221-1229, 1992), we observed that cells deleted for the PKC1 gene are viable when grown on osmotically stabilized medium but are osmotically fragile and lyse rapidly after a shift to hypotonic medium. As shown by light and electron microscopic examinations, the delta pkc1 strain exhibits many cells with a strongly elongated bud or chains of incompletely budded cells when grown on solid medium.
分离出了酿酒酵母的7个温度敏感型细胞裂解（cly）突变菌株，这些菌株在限制温度下于低渗培养基上裂解，但在渗透压支持的培养基上不裂解。这7个突变体分为4个互补群，即CLY12至CLY15。通过互补cly15温度敏感型生长缺陷分离出了野生型CLY15基因。序列分析表明，互补DNA片段编码部分PKC1基因，该基因先前已作为哺乳动物蛋白激酶C基因的酿酒酵母同源物被分离出来（D.E.莱文、F.O.菲尔兹、R.邦泽瓦、J.M.毕晓普和J.索纳，《细胞》62:213 - 224，1990）。随后的遗传分析表明，CLY15和PKC1在酵母基因组中代表相同的基因座。仅编码预测的Pkc1p催化结构域的截短PKC1基因能够互补pkc1突变菌株。与最近报道的情况类似（D.E.莱文和E.巴特利特 - 霍伊布施，《细胞生物学杂志》116:1221 - 1229，1992），我们观察到，缺失PKC1基因的细胞在渗透压稳定的培养基上生长时是存活的，但渗透压敏感且在转移至低渗培养基后迅速裂解。如光镜和电镜检查所示，Δpkc1菌株在固体培养基上生长时，许多细胞具有强烈伸长的芽或不完全出芽细胞的链。
