Adenylyl cyclase is dispensable for vegetative cell growth in the fission yeast Schizosaccharomyces pombe.
Adenylyl cyclase is dispensable for vegetative cell growth in the fission yeast Schizosaccharomyces pombe.
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腺苷酸环化酶对于裂殖酵母裂殖酵母的营养细胞生长是必不可少的。
DOI：
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发表时间：
1990
影响因子：
11.1
通讯作者：
Masayuki Yamamoto
中科院分区：
文献类型：
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作者：
Tatsuya Maeda;Nobuyoshi Mochizuki;Masayuki Yamamoto
破坏裂殖酵母（Schizosophyomycespombe）编码腺苷酸环化酶的基因，并没有对裂殖酵母细胞产生致死性，尽管它们在完全培养基中的生长速度比野生型菌株慢40%。这些细胞不含可测量量的cAMP，也不含腺苷酸环化酶活性。当h ~+和h ~-干扰子混合时，即使在丰富培养基中也能发生交配.同宗配合系的B11破坏物的繁殖是困难的，可能是因为这样的细胞容易交配和产生子囊，从而停止生长。当将克隆的p53 1+引入粟酒裂殖酵母细胞的多拷贝质粒中时，观察到p53 1 mRNA的量增加了10倍以上。总腺苷酸环化酶活性在这些转化体中同样高。然而，细胞内cAMP的水平几乎没有受到影响。有证据表明，这不是由于磷酸二酯酶活性增加。因此，在分裂酵母细胞中的cAMP水平似乎不是由腺苷酸环化酶蛋白的量调节，而是由酶水平的反馈机制调节。在氮饥饿下cAMP水平下降约50%，这触发了粟酒裂殖酵母的性发育。我们认为，裂殖酵母控制细胞内cAMP的水平主要是为了调节性发育，而不是驱动或阻止细胞周期。
Disruption of the cyr1 gene of Schizosaccharomyces pombe, which encodes adenylyl cyclase, did not confer lethality to fission yeast cells, although they grew 40% slower than wild-type strains in complete medium. These cells contained no measurable amount of cAMP and no adenylyl cyclase activity. When h+ and h- cyr1 disruptants were mixed, they underwent mating even in rich medium. Propagation of homothallic cyr1 disruptants was difficult, probably because such cells readily mate and produce asci and thus stop growing. A greater than 10-fold increase in the amount of cyr1 mRNA was observed when cloned cyr1+ was introduced into Sch. pombe cells on a multicopy plasmid. The total adenylyl cyclase activity was similarly high in these transformants. However, the level of intracellular cAMP was hardly affected. Evidence suggests that this was not due to increased phosphodiesterase activity. Thus, cAMP level in growing fission yeast cells appears to be regulated not by the amount of adenylyl cyclase protein but by a feedback mechanism at the enzyme level. The cAMP level fell by approximately 50% under nitrogen starvation, which triggers sexual development in Sch. pombe. We suggest that fission yeast controls the level of intracellular cAMP primarily to regulate sexual development rather than to drive or arrest the cell cycle.