外源肌醇和负责肌醇转运的基因是粟酒裂殖酵母交配和孢子形成所必需的。

Exogenous inositol and genes responsible for inositol transport are required for mating and sporulation in Shizosaccharomyces pombe.

作者信息

Niederberger C, Gräub R, Schweingruber A M, Fankhauser H, Rusu M, Poitelea M, Edenharter L, Schweingruber M E

机构信息

Institute of General Microbiology, University of Bern, Switzerland.

出版信息

Curr Genet. 1998 Apr;33(4):255-61. doi: 10.1007/s002940050334.

DOI:10.1007/s002940050334

PMID:9560432

Abstract

Fission yeast, Schizosaccharomyces pombe, is a natural inositol auxotroph. We show here that the amount of exogenous inositol added to the medium is critical for the control of its life cycle. Above growth-limiting concentrations inositol stimulates mating and sporulation in minimal medium. The effect of inositol is also observed on yeast-extract-medium plates. We selected a mutant, IM49, which mates and sporulates only poorly and show that it is defective in inositol transport. Its defect is in a gene (itr2) coding for a putative 12 membrane-spanning protein. The polypeptide contains the two sugar-transport motifs typical for hexose transporters and shows good homology to the two Saccharomyces cerevisiae inositol transporters. The itr2 gene is essential for cell growth and its mRNA level is repressed by glucose. Mutant IM49 is also complemented by a multicopy suppressor gene (itr1) which codes for a putative hexose transporter with unknown substrate specifity.

摘要

裂殖酵母，粟酒裂殖酵母，是一种天然的肌醇营养缺陷型。我们在此表明，添加到培养基中的外源肌醇量对于其生命周期的控制至关重要。在生长限制浓度以上，肌醇会刺激基本培养基中的交配和孢子形成。在酵母提取物培养基平板上也观察到了肌醇的作用。我们筛选出了一个突变体IM49，它的交配和孢子形成能力很差，并表明它在肌醇转运方面存在缺陷。其缺陷在于一个编码假定的12次跨膜蛋白的基因（itr2）。该多肽含有己糖转运蛋白典型的两个糖转运基序，并且与两种酿酒酵母肌醇转运蛋白具有良好的同源性。itr2基因对于细胞生长至关重要，其mRNA水平受到葡萄糖的抑制。突变体IM49也可由一个多拷贝抑制基因（itr1）互补，该基因编码一种底物特异性未知的假定己糖转运蛋白。