Kanik-Ennulat C, Montalvo E, Neff N
Program in Molecular Biology Memorial Sloan-Kettering Cancer Center, New York, NY 10021, USA.
Genetics. 1995 Jul;140(3):933-43. doi: 10.1093/genetics/140.3.933.
Orthovanadate is a small toxic molecule that competes with the biologically important oxyanion orthophosphate. Orthovanadate resistance arises spontaneously in Saccharomyces cerevisiae haploid cells by mutation in a number of genes. Mutations selected at 3 nM sodium orthovanadate have different degrees of vanadate resistance, hygromycin sensitivity, detergent sensitivity and sporulation defects. Recessive vanadate-resistant mutants belong to at least six genetic loci. Most mutants are defective in outer chain glycosylation of secreted invertase (van1, van2, van4, van5, van6, VAN7-116 and others), a phenotype found in some MNN or VRG mutants. The phenotypes of these vanadate-resistant mutants are consistent with an alteration in the permeability or specificity of the Golgi apparatus. The previously published VAN1 gene product has a 200 amino acid domain with 40% identity with the MNN9 gene product and 70% identity with the ANP1 gene product. Cells containing the van1-18, mnn9 (vrg6) or anp1 mutations have some phenotypic similarities. The VAN2 gene was isolated and its coding region is identified and reported. It is an essential gene on chromosome XV and its translated amino acid sequence predicts a unique 337 amino acid protein with multiple transmembrane domains.
原钒酸盐是一种有毒的小分子，它与具有生物学重要性的含氧阴离子正磷酸盐相互竞争。酿酒酵母单倍体细胞中，原钒酸盐抗性可通过多个基因的突变自发产生。在3 nM原钒酸钠条件下筛选出的突变体具有不同程度的钒酸盐抗性、潮霉素敏感性、去污剂敏感性和孢子形成缺陷。隐性钒酸盐抗性突变体至少属于六个基因位点。大多数突变体在分泌型转化酶的外链糖基化方面存在缺陷（van1、van2、van4、van5、van6、VAN7-116等），这是一些MNN或VRG突变体中发现的表型。这些钒酸盐抗性突变体的表型与高尔基体通透性或特异性的改变一致。先前发表的VAN1基因产物有一个200个氨基酸的结构域，与MNN9基因产物有40%的同源性，与ANP1基因产物有70%的同源性。含有van1-18、mnn9（vrg6）或anp1突变的细胞有一些表型相似性。VAN2基因已被分离，其编码区已被鉴定并报道。它是位于第十五号染色体上的一个必需基因，其翻译后的氨基酸序列预测为一种具有多个跨膜结构域的独特的337个氨基酸的蛋白质。
