SACCHAROMYCES-CEREVISIAE PROTEIN INVOLVED IN PLASMID MAINTENANCE IS NECESSARY FOR MATING OF MAT-ALPHA CELLS
SACCHAROMYCES-CEREVISIAE PROTEIN INVOLVED IN PLASMID MAINTENANCE IS NECESSARY FOR MATING OF MAT-ALPHA CELLS
复制标题
DOI：
10.1016/0022-2836(88)90358-0
复制
发表时间：
1988-12-05
影响因子：
5.6
通讯作者：
TYE, BK
中科院分区：
文献类型：
--
作者：
PASSMORE, S;MAINE, GT;TYE, BK
我们以前报道的分离酵母突变体，似乎影响某些自主复制序列（ARS）的功能。这些突变体因其在维持微型染色体方面的缺陷而被称为mcm。我们现在已经更详细地描述了一个ARS特异性突变，mcm 1 -1。这种Mcm 1突变体具有第二种表型;MATα mcm 1 -1菌株是不育的。MCM 1与其他已知的α特异性不育突变是非等位基因，并且与大多数交配所需的基因不同，它对于生长至关重要。themcm 1 -1突变体的α-特异不育表型表现为不能产生正常量的交配信息素α-因子。此外，在该突变体中，分别编码α-因子前体和α-因子受体的MF α1和STE 3基因的转录物大大减少。我们已经克隆、定位和测序了MCM 1的野生型和突变型等位基因，它位于染色体XIII的右臂靠近LYS 7。MCM 1基因产物由286个氨基酸残基组成，其中20个氨基酸残基中有19个是天冬氨酸或谷氨酸，随后是一系列谷氨酰胺片段，与精氨酸代谢途径的调控基因ARG 80具有显著的同源性，ARG 80位于MCM 1上游约700个碱基对处。在多聚阴离子区之前的第97位氨基酸被亮氨酸取代为脯氨酸，这被证明是导致themcm 1 -1突变体的α特异性不育和微小染色体维持缺陷表型的原因。
We previously reported the isolation of yeast mutants that seem to affect the function of certain autonomously replicating sequences (ARSs). These mutants are known asmcmfor their defect in the maintenance of minichromosomes. We have now characterized in more detail oneARS-specific mutation,mcm1-1. This Mcm1 mutant has a second phenotype;MATαmcm1-1 strains are sterile.MCM1 is non-allelic to other known α-specific sterile mutations and, unlike most genes required for mating, it is essential for growth. The α-specific sterile phenotype of themcm1-1 mutant is manifested by its failure to produce a normal amount of the mating pheromone, α-factor. In addition, transcripts of theMFα1 andSTE3 genes, which encode the α-factor precursor and thea-factor receptor, respectively, are greatly reduced in this mutant. These and other properties of themcm1-1 mutant suggest that theMCM1 protein may act as a transcriptional activator of α-specific genes.We have cloned, mapped and sequenced the wild-type and mutant alleles ofMCM1, which is located on the right arm of chromosome XIII nearLYS7. TheMCM1 gene product is a protein of 286 amino acid residues and contains an unusual region in which 19 out of 20 residues are either aspartic or glutamic acid, followed by a series of glutamine tracts.MCM1 has striking homology toARG80, a regulatory gene of the arginine metabolic pathway located about 700 base-pairs upstream fromMCM1. A substitution of leucine for proline at amino acid position 97, immediately preceding the polyanionic region, was shown to be responsible for both the α-specific sterile and minichromosome-maintenance defective phenotypes of themcm1-1 mutant.