Shi Xiao-Zhong, Ao Shi-Zhou
State Key Laboratory of Molecular Biology, Institute of Biochemistry and Cell biology, Shanghai Institutes for Biological Sciences, the Chinese Academy of Sciences, Shanghai 200031, China.
Sheng Wu Hua Xue Yu Sheng Wu Wu Li Xue Bao (Shanghai). 2002 Jul;34(4):433-8.
PCL6, PCL7(PAP1), and PHO80 belong to the PHO80 subfamily of PCLs (PHO85 cyclins), share high homology in protein sequences, and function with some similarity. YLR190w, the substrate of PCL7-PHO85, shares homology with YJL084c in a 140-amino-acid region. In addition, YJL084c was reported as a PCL6-binding protein. Here, it was found that there was association between YJL084c and PCL7, and their interaction was confirmed by co-immunoprecipitation assay and GST pull-down assay. The in vitro translational product of YJL084c could be phosphorylated by PCL7-PHO85 complex. Also, the GST fusion protein of the middle region expressed in E.coli could be phosphorylated, while the amino terminal or the carboxyl terminal could not. Interestingly, PCL6-PHO85 complex had the same characters; effect of phosphate condition on the phosphorylation was shown in both PCL6-PHO85 and PCL7-PHO85. YPH499: Yjl084c :: LEU2 was constructed by homologous recombination. PUT4 was reported as a YJL084c-binding protein, but no difference was observed between wild strain and the Yjl084c null mutant on MP medium. In addition, the interaction between PHO81 and all of the three cyclins was analyzed.
PCL6、PCL7（PAP1）和PHO80属于PCL（PHO85细胞周期蛋白）的PHO80亚家族，在蛋白质序列上具有高度同源性，并且功能有一定相似性。PCL7 - PHO85的底物YLR190w在一个140个氨基酸的区域内与YJL084c具有同源性。此外，YJL084c被报道为一种PCL6结合蛋白。在此，发现YJL084c与PCL7之间存在关联，并且通过免疫共沉淀实验和谷胱甘肽 - S - 转移酶（GST）下拉实验证实了它们之间的相互作用。YJL084c的体外翻译产物可被PCL7 - PHO85复合物磷酸化。同样，在大肠杆菌中表达的中间区域的GST融合蛋白可被磷酸化，而氨基末端或羧基末端则不能。有趣的是，PCL6 - PHO85复合物也有相同的特性；磷酸盐条件对PCL6 - PHO85和PCL7 - PHO85的磷酸化均有影响。通过同源重组构建了YPH499：Yjl084c :: LEU2。PUT4被报道为一种YJL084c结合蛋白，但在MP培养基上野生型菌株和Yjl084c缺失突变体之间未观察到差异。此外，还分析了PHO81与所有这三种细胞周期蛋白之间的相互作用。
