Tasaka Y, Nakagawa Y, Sato C, Mino M, Uozumi N, Murata N, Muto S, Iida H
Research Institute for Biological Sciences, 7549-1 Yoshikawa, Kayo, Joubo, Okayama, 716-1241, Japan.
Biochem Biophys Res Commun. 2000 Mar 5;269(1):265-9. doi: 10.1006/bbrc.2000.2278.
The Saccharomyces cerevisiae MID1 gene encodes a stretch-activated Ca(2+)-permeable channel. In a protein database, we found a Schizosaccharomyces pombe gene whose predicted protein shows 26% identical and 62% similar to the Mid1 channel in amino acid sequence. cDNA derived from this gene, designated yam8(+), was isolated by reverse transcription-polymerase chain reaction (RT-PCR). Further analysis showed that the Yam8 protein consists of 486 amino acids and has 6 hydrophobic segments. The yam8(+) cDNA, placed under the S. cerevisiae TDH3 promoter, partially complemented the mating pheromone-induced death (mid) phenotype of the S. cerevisiae mid1 mutant. The expression of the yam8(+) cDNA in the mid1 mutant cells partially remediated the mid phenotype and resulted in a slight increase in Ca(2+) uptake activity. These findings suggest that Yam8 is a potential homologue of Mid1.
酿酒酵母MID1基因编码一种牵张激活的Ca(2+)通透通道。在一个蛋白质数据库中，我们发现了一种粟酒裂殖酵母基因，其预测的蛋白质在氨基酸序列上与Mid1通道有26%的同一性和62%的相似性。通过逆转录聚合酶链反应（RT-PCR）分离出了源自该基因的cDNA，命名为yam8(+)。进一步分析表明，Yam8蛋白由486个氨基酸组成，有6个疏水片段。置于酿酒酵母TDH3启动子下的yam8(+) cDNA部分互补了酿酒酵母mid1突变体的交配信息素诱导死亡（mid）表型。yam8(+) cDNA在mid1突变体细胞中的表达部分修复了mid表型，并导致Ca(2+)摄取活性略有增加。这些发现表明Yam8是Mid1的潜在同源物。
