Martegani E, Vanoni M, Zippel R, Coccetti P, Brambilla R, Ferrari C, Sturani E, Alberghina L
Dipartimento di Fisiologia e Biochimica Generali, Università degli Studi di Milano, Italy.
EMBO J. 1992 Jun;11(6):2151-7. doi: 10.1002/j.1460-2075.1992.tb05274.x.
In the yeast Saccharomyces cerevisiae genetic and biochemical evidence indicates that the product of the CDC25 gene activates the RAS/adenylyl cyclase/protein kinase A pathway by acting as a guanine nucleotide protein. Here we report the isolation of a mouse brain cDNA homologous to CDC25. The mouse cDNA, called CDC25Mm, complements specifically point mutations and deletion/disruptions of the CDC25 gene. In addition, it restores the cAMP levels and CDC25-dependent glucose-induced cAMP signalling in a yeast strain bearing a disruption of the CDC25 gene. The CDC25Mm-encoded protein is 34% identical with the catalytic carboxy terminal part of the CDC25 protein and shares significant homology with other proteins belonging to the same family. The protein encoded by CDC25Mm, prepared as a glutathione S-transferase fusion in Escherichia coli cells, activates adenylyl cyclase in yeast membranes in a RAS2-dependent manner. Northern blot analysis of mouse brain poly(A)+ RNA reveals two major transcripts of approximately 1700 and 5200 nucleotides. Transcripts were found also in mouse heart and at a lower level in liver and spleen.
在酿酒酵母中，遗传学和生物化学证据表明，CDC25基因的产物作为一种鸟嘌呤核苷酸蛋白激活RAS/腺苷酸环化酶/蛋白激酶A途径。在此，我们报道了一个与CDC25同源的小鼠脑cDNA的分离。这个小鼠cDNA，称为CDC25Mm，能特异性地互补CDC25基因的点突变以及缺失/破坏。此外，它能恢复携带CDC25基因破坏的酵母菌株中的cAMP水平以及CDC25依赖的葡萄糖诱导的cAMP信号传导。CDC25Mm编码的蛋白与CDC25蛋白的催化性羧基末端部分有34%的同一性，并且与同一家族的其他蛋白有显著的同源性。在大肠杆菌细胞中作为谷胱甘肽S-转移酶融合蛋白制备的CDC25Mm编码的蛋白，以RAS2依赖的方式激活酵母膜中的腺苷酸环化酶。对小鼠脑poly(A)+ RNA的Northern印迹分析揭示了大约1700和5200个核苷酸的两个主要转录本。在小鼠心脏中也发现了转录本，在肝脏和脾脏中的水平较低。
