Sato S, Suzuki H, Widyastuti U, Hotta Y, Tabata S
Department of Biology, School of Science, Nagoya University, Japan.
Curr Genet. 1994 Jul;26(1):31-7. doi: 10.1007/BF00326301.
Five cDNA clones, harboring genetic messages preferentially expressed during the sexual differentiation process, were isolated from a cDNA library of Schizosaccharomyces pombe by subtractive screening. Transcription of the corresponding genes, termed isp3, 4, 5, 6, and 7, was dependent on nitrogen starvation and their induction occurred at several stages of spore formation. Analysis of the cDNA primary structures revealed a capacity for the coding of polypeptides of 19.2 kDa, 88.3 kDa, 60.1 kDa, 49.7 kDa, and 43.8 kDa, respectively. The translated amino-acid sequences of isp5 and isp6 were found to show significant similarities to those of amino-acid permeases and proteinase B of Saccharomyces cerevisiae, respectively. Disruption of isp6 arrested the cell cycle prior to conjugation and caused a drastic blocking effect on spore formation.
通过消减筛选，从粟酒裂殖酵母的cDNA文库中分离出五个cDNA克隆，它们含有在性别分化过程中优先表达的遗传信息。相应基因（命名为isp3、4、5、6和7）的转录依赖于氮饥饿，并且它们的诱导发生在孢子形成的几个阶段。对cDNA一级结构的分析表明，它们分别能够编码19.2 kDa、88.3 kDa、60.1 kDa、49.7 kDa和43.8 kDa的多肽。发现isp5和isp6的翻译氨基酸序列分别与酿酒酵母的氨基酸通透酶和蛋白酶B的序列有显著相似性。isp6的破坏在接合之前使细胞周期停滞，并对孢子形成产生强烈的阻断作用。
