Belda F, Zárate V
Departmento de Microbiologia y Biologia Celular, Facultad de Farmacia, Universidad de La Laguna, Tenerife, Spain.
Yeast. 1996 May;12(6):555-64. doi: 10.1002/(SICI)1097-0061(199605)12:6%3C555::AID-YEA939%3E3.0.CO;2-M.
Three Schizosaccharomyces pombe fragile mutants requiring the presence of an osmotic stabilizer to grow, that lyse when transferred into hypotonic solutions and that secrete to the extracellular medium more protein than the parental strain were isolated. In the three mutants, the fragile phenotype segregated in a Mendelian fashion, indicating a single chromosomal gene mutation, and behaved as a recessive character. By complementation analysis, the three fragile mutants fell in a single complementation group, defining the same gene (SRB1). Mutations of this gene are responsible for alterations in the cells such as fragile character, increase in the cell wall porosity, changes in the cell morphology and floc-forming ability. The study of the three srb1 alleles indicated that the degree of these alterations is proportional to a significant decrease in the galactomannan fraction of the mutants cell wall. The data presented in this report suggest that the product of the SRB1 gene is critical for the maintenance of the integrity and structure of Sz. pombe cell wall.
分离出了三个粟酒裂殖酵母脆性突变体，它们需要渗透稳定剂的存在才能生长，转移到低渗溶液中会裂解，并且比亲代菌株向细胞外培养基分泌更多的蛋白质。在这三个突变体中，脆性表型以孟德尔方式分离，表明是单个染色体基因突变，并且表现为隐性性状。通过互补分析，这三个脆性突变体属于同一个互补群，定义了同一个基因（SRB1）。该基因的突变导致细胞出现诸如脆性特征、细胞壁孔隙率增加、细胞形态变化和絮凝形成能力改变等变化。对三个srb1等位基因的研究表明，这些变化的程度与突变体细胞壁中半乳甘露聚糖部分的显著减少成正比。本报告中的数据表明，SRB1基因的产物对于维持粟酒裂殖酵母细胞壁的完整性和结构至关重要。
