过量表达蛋白激酶YPK1使酵母细胞对高盐胁迫的高度敏感依赖于雷帕霉素靶蛋白

YPK1 overexpression resulted salt stress hypersensitivity in Saccharomyces cerevisiae is dependent on TOR1

YPK1是酵母中和哺乳动物蛋白激酶SGK同源的一种丝氨酸3苏氨酸蛋白激酶,在酿酒酵母(Saccharomyces cerevisiae)生理调节中有重要的作用,和酵母细胞壁的完整性、细胞骨架中肌动蛋白极性、细胞内吞作用、细胞在氮源缺乏和营养条件调节下细胞内部的翻译情况密切相关。【目的】为了深入研究YPK1蛋白激酶的细胞功能以及在细胞信号传导中的作用,【方法】我们构建了过量表达YPK1的高拷贝质粒,研究了过量表达YPK1的酵母细胞在盐胁迫条件下的生长情况,【结果】发现过量表达YPK1会导致酵母细胞对盐胁迫高度敏感,并且这种敏感性依赖于TOR1的存在。【结论】我们的研究结果首次初步揭示YPK1与细胞盐胁迫应答的关系,并初步证明YPK1的功能充分发挥需要TOR1的参与。

Serine/threonine protein kinase YPK1, a homologue of mammalian protein kinase serum and glucoeortieoid-indueible kinase （SGK）, plays important physiological roles in Saccharomyces cerevisiae. It involves in cell wall maintenance, actin cytoskeleton dynamics, endocytosis, translation during nitrogen starvation and nutrient sensing. [ Objective] In order to further explore the cellular function of YPKI and the its transduction pathway. [ Methods] We overexpressed YPKI in wild type and torl mutant cells and monitored the cell growth responding to salt stress. [ Results] We found that YPK1 overexpression resulted salt stress hypersensitivity in wild type cells and this hypersensitivity was abolished by torl mutant. [ Conclusion] Our results indicate that YPK1 may interact with target of rapamycin （TOR1） to regulate the salt stress response.