THE SACCHAROMYCES-CEREVISIAE FKS1 (ETG1) GENE ENCODES AN INTEGRAL MEMBRANE-PROTEIN WHICH IS A SUBUNIT OF 1,3-BETA-D-GLUCAN SYNTHASE
THE SACCHAROMYCES-CEREVISIAE FKS1 (ETG1) GENE ENCODES AN INTEGRAL MEMBRANE-PROTEIN WHICH IS A SUBUNIT OF 1,3-BETA-D-GLUCAN SYNTHASE
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DOI：
10.1073/pnas.91.26.12907
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发表时间：
1994-12-20
影响因子：
11.1
通讯作者：
KURTZ, MB
中科院分区：
文献类型：
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作者：
DOUGLAS, CM;FOOR, F;KURTZ, MB
在酿酒酵母中，FKS 1突变赋予对免疫抑制剂FK 506和环孢菌素A的超敏反应，而ETG 1突变赋予对细胞壁活性棘白菌素（1，3-β-D-葡聚糖合酶抑制剂）的抗性，并且在某些情况下，伴随对几丁质合酶抑制剂尼可霉素Z的超敏反应。通过这些表型的互补克隆FKS 1和ETG 1基因，发现它们是相同的。该基因的破坏导致（i）明显的生长缓慢表型，（ii）对FK 506和环孢菌素A的超敏反应，（iii）对棘白菌素的敏感性略有增加，（iv）体外1，3-β-D-葡聚糖合酶活性显著降低。核苷酸序列编码的215 kDa的多肽预测是一个完整的膜蛋白与16个跨膜螺旋，与以前的观察结果一致，etg 1 -1突变的结果在棘白菌素抗性葡聚糖合酶活性与不可提取的膜部分的酶。这些结果表明FKS 1编码1，3-β-D-葡聚糖合酶的亚基。破坏突变体中存在的残余活性、基因的非必需性质以及Southern印迹杂交分析的结果表明存在葡聚糖合酶同工酶。
In Saccharomyces cerevisiae, mutations in FKS1 confer hypersensitivity to the immunosuppressants FK506 and cyclosporin A, while mutations in ETG1 confer resistance to the cell-wall-active echinocandins (inhibitors of 1,3-beta-D-glucan synthase) and, in some cases, concomitant hypersensitivity to the chitin synthase inhibitor nikkomycin Z. The FKS1 and ETG1 genes were cloned by complementation of these phenotypes and were found to be identical. Disruption of the gene results in (i) a pronounced slow-growth phenotype, (ii) hypersensitivity to FK506 and cyclosporin A, (iii) a slight increase in sensitivity to echinocandin, and (iv) a significant reduction in 1,3-beta-D-glucan synthase activity in vitro. The nucleotide sequence encodes a 215-kDa polypeptide predicted to be an integral membrane protein with 16 transmembrane helices, consistent with previous observations that the etg1-1 mutation results in echinocandin-resistant glucan synthase activity associated with the nonextractable membrane fraction of the enzyme. These results suggest that FKS1 encodes a subunit of 1,3-beta-D-glucan synthase. The residual activity present in the disruption mutant, the nonessential nature of the gene, and results of Southern blot hybridization analysis point to the existence of a glucan synthase isozyme.