Robinson M K, van Zyl W H, Phizicky E M, Broach J R
Department of Biochemistry, University of Rochester Medical School, New York 14642.
Mol Cell Biol. 1994 Jun;14(6):3634-45. doi: 10.1128/mcb.14.6.3634-3645.1994.
The Saccharomyces cerevisiae TPD1 gene has been implicated in tRNA splicing because a tpd1-1 mutant strain accumulates unspliced precursor tRNAs at high temperatures (W. H. van Zyl, N. Wills, and J. R. Broach, Genetics 123:55-68, 1989). The wild-type TPD1 gene was cloned by complementation of the tpd1-1 mutation and shown to encode a protein with substantial homology to protein phosphatase 2C (PP2C) of higher eukaryotes. Expression of Tpd1p in Escherichia coli results in PP2C-like activity. Strains deleted for the TPD1 gene exhibit multiple phenotypes: temperature-sensitive growth, accumulation of unspliced precursor tRNAs, sporulation defects, and failure of cell separation during mitotic growth. On the basis of the presence of these observable phenotypes and the fact that Tpd1p accounts for a small percentage of the observed PP2C activity, we argue that Tpd1p is a unique member of the PP2C family.
酿酒酵母TPD1基因与tRNA剪接有关，因为tpd1 - 1突变株在高温下会积累未剪接的前体tRNA（W. H. 范齐尔、N. 威尔斯和J. R. 布罗奇，《遗传学》123:55 - 68，1989年）。通过互补tpd1 - 1突变克隆了野生型TPD1基因，结果表明它编码一种与高等真核生物的蛋白磷酸酶2C（PP2C）具有高度同源性的蛋白质。Tpd1p在大肠杆菌中的表达产生了类似PP2C的活性。缺失TPD1基因的菌株表现出多种表型：温度敏感型生长、未剪接前体tRNA的积累、孢子形成缺陷以及有丝分裂生长期间细胞分离失败。基于这些可观察到的表型的存在以及Tpd1p仅占所观察到的PP2C活性的一小部分这一事实，我们认为Tpd1p是PP2C家族的一个独特成员。
