Lee D H, Tanaka K, Tamura T, Chung C H, Ichihara A
Department of Molecular Biology, College of Natural Sciences, Seoul National University, Korea.
Biochem Biophys Res Commun. 1992 Jan 31;182(2):452-60. doi: 10.1016/0006-291x(92)91753-d.
We found by computer analysis that a putative yeast proteasome subunit gene named PRS3 that encodes a protein very similar to subunit C5 of rat and human proteasomes is located immediately 3' to the ERD2 gene of Saccharomyces cerevisiae. The similarity of the primary structures of the two suggests that this subunit may have a common function in proteasomes of all eukaryotes. The protein, deduced from the open reading frame of PRS3, consists of 242 amino acid residues with a calculated molecular weight of 27,077. Chromosomal disruption of the PRS3 gene created a recessive lethal mutation. Physical mapping by hybridization to intact S. cerevisiae chromosomal DNA showed that the PRS3 gene is located on chromosome II, unlike two other subunit genes, PRS1 and PRS2, which are located on chromosomes XV and VII, respectively. These findings indicate that the PRS3 protein is a subunit of yeast proteasomes that is essential for cell viability.
我们通过计算机分析发现，一个名为PRS3的假定酵母蛋白酶体亚基基因位于酿酒酵母ERD2基因的紧挨着的3'端，该基因编码一种与大鼠和人类蛋白酶体的C5亚基非常相似的蛋白质。两者一级结构的相似性表明，该亚基可能在所有真核生物的蛋白酶体中具有共同功能。从PRS3的开放阅读框推导出来的蛋白质由242个氨基酸残基组成，计算分子量为27,077。PRS3基因的染色体破坏产生了隐性致死突变。通过与完整的酿酒酵母染色体DNA杂交进行物理图谱分析表明，PRS3基因位于第二条染色体上，这与另外两个亚基基因PRS1和PRS2不同，它们分别位于第十五条和第七条染色体上。这些发现表明，PRS3蛋白是酵母蛋白酶体的一个亚基，对细胞活力至关重要。
