Watanabe N, Vande Woude G F, Ikawa Y, Sagata N
Tsukuba Life Science Center Riken, Ibaraki, Japan.
Nature. 1989 Nov 30;342(6249):505-11. doi: 10.1038/342505a0.
The Xenopus c-mos proto-oncogene product, pp39mos, accumulates in the unfertilized egg during maturation, is hyperphosphorylated and exhibits protein kinase activity. On fertilization, or soon after the completion of meiosis, the accumulated pp39mos undergoes selective proteolysis. Using an in vitro protease assay system, we show here that this specific proteolysis is caused by the calcium-dependent cysteine protease, calpain.
非洲爪蟾c-mos原癌基因产物pp39mos在成熟过程中于未受精卵中积累，发生超磷酸化并表现出蛋白激酶活性。受精时或减数分裂完成后不久，积累的pp39mos会经历选择性蛋白水解。利用体外蛋白酶检测系统，我们在此表明这种特异性蛋白水解是由钙依赖性半胱氨酸蛋白酶钙蛋白酶引起的。
