Specific proteolysis of the c-mos proto-oncogene product by calpain on fertilization of Xenopus eggs.
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.
Watanabe
N
N
Tsukuba Life Science Center Riken, Ibaraki, Japan.
Vande Woude
G F
GF
Ikawa
Y
Y
Sagata
N
N
D000818:Animals; D002154:Calpain / Q000378:metabolism*; D005306:Fertilization; D005786:Gene Expression Regulation; D006133:Growth Substances / Q000378:metabolism; D016200:Maturation-Promoting Factor; D008540:Meiosis; D008970:Molecular Weight; D009865:Oocytes / Q000502:physiology*; D010766:Phosphorylation; D011374:Progesterone / Q000494:pharmacology; D011518:Proto-Oncogene Proteins / Q000378:metabolism*; D017231:Proto-Oncogene Proteins c-mos; D012333:RNA, Messenger / Q000235:genetics; D013997:Time Factors; D014982:Xenopus laevis
D006133:Growth Substances; D011518:Proto-Oncogene Proteins; D012333:RNA, Messenger; D011374:Progesterone; D017231:Proto-Oncogene Proteins c-mos; D016200:Maturation-Promoting Factor; D002154:Calpain