酿酒酵母和粟酒裂殖酵母细胞增殖对Ca~(2 )依赖性的比较研究

同样实验条件下Ca~(2 )对S.cerevisiae的增殖没有影响,但能明显促进S.pombe的增殖;Ca~(2 )螯合剂EGTA对S.cerevisiae的增殖没有明显抑制作用,但对S.pombe的增殖有显著的抑制作用,回加Ca~(2 )能够有效消除EGTA的抑制作用;而非特异性螯合剂EDTA虽然对两类酵母细胞的增殖都有抑制作用,但Ca~(2 )却不能消除EDTA的抑制作用,这样就直接指明了两类酵母对胞外Ca~(2 )的依赖性是不一样的。由于S.cerevisiae细胞的增殖速率比S.pombe细胞要快近3倍,且与转化细胞或肿瘤细胞具有类似的细胞增殖不依赖于胞外Ca~(2 )的特性,说明研究胞外Ca~(2 )对这两类酵母细胞增殖不同作用效应的机制,对搞清细胞周期失控与细胞转化之间的关系有重要的意义。

COMPARATIVE STUDY OF DEPENDENCE OF THE CELL PROLIFERATION OF SACCHAROMYCES CEREVISIAE AND SCHIZOSACCHAROMYCES POMBE ON Ca~(2 )

Under the same experimental conditions, exogenous Ca2 had no effect on the proliferation of 5. cerevisiae, but it could obviously stimulate the proliferation of S. pombe. Caz chelator EG-TA had no inhibition effect on the proliferation of S. cerevisiae, but it apparently inhibited the proliferation of S. pombe and the inhibition could be effectively overcome by adding Ca2 . Non-special ion chelator EDTA could inhibit the proliferation of both S. cerevisiae and 5. pombe, but the inhibition could not be overcome by adding Ca2 . The results above directly showed that the depen-dence of the proliferation of the two kinds of yeast on exogenous Ca2 was different. The growth rate of S. cerevisiae was about 3 times that of S. pombe and the proliferation of 5. cerevisiae was independent on the exogenous Ca2 , which was similar to transformed cells. Therefore, in order to understand the relationship between the disorder of cell cycle and cell transformation, it was very important to study the mechanism of different effects of exogenous Ca2 on the proliferation of the two kinds of yeast.