Marcus S, Xue C B, Naider F, Becker J M
Department of Microbiology, University of Tennessee, Knoxville 37996.
Mol Cell Biol. 1991 Feb;11(2):1030-9. doi: 10.1128/mcb.11.2.1030-1039.1991.
Mating response between opposite mating types of Saccharomyces cerevisiae is dependent upon alpha factor, a tridecapeptide, and a-factor, an isoprenylated, methyl esterified dodecapeptide whose interaction with the alpha target cell has not been characterized. We report on the first biochemical and physiological evidence of an alpha-mating-type-specific a-factor-degrading activity. Radioiodinated a-factor was used to identify the a-factor-degrading activity, which is cell associated, endoproteolytic, and not required for response to pheromone. a-factor degradation was not energy dependent, nor did it require pheromone internalization or interaction with its receptor. Phenylmethylsulfonyl fluoride and tosyl-L-arginyl-methyl ester inhibited degradation of a-factor and increased the time required by alpha cells to recover from a-factor-induced growth arrest and morphological alteration, providing evidence that a-factor degradation plays a role in the recovery of alpha cells from the pheromone response.
酿酒酵母（Saccharomyces cerevisiae）相对交配型之间的交配反应取决于α因子（一种十三肽）和a因子（一种异戊烯化、甲酯化的十二肽，其与α靶细胞的相互作用尚未明确）。我们报告了首个关于α交配型特异性a因子降解活性的生化和生理学证据。放射性碘化a因子被用于鉴定a因子降解活性，该活性与细胞相关，是内切蛋白水解活性，且对信息素的反应并非必需。a因子降解不依赖能量，也不需要信息素内化或与受体相互作用。苯甲基磺酰氟和甲苯磺酰-L-精氨酸甲酯抑制a因子的降解，并延长了α细胞从a因子诱导的生长停滞和形态改变中恢复所需的时间，这表明a因子降解在α细胞从信息素反应中恢复的过程中发挥作用。
