Calmodulin synthesis and accumulation during oogenesis and maturation of Xenopus laevis oocytes.
The calmodulin levels in stage 6 Xenopus oocytes averaged 89 +/- 24 (SD) ng/oocyte and had largely accumulated by stage 3 of oogenesis. From stage 3 to early stage 6, calmodulin levels did not increase further. However, in large stage 6 oocytes (greater than 1.25 mm diam) calmodulin levels again rose to a level as high as 121 ng/oocyte. Calmodulin levels did not change during the maturation of stage 6 oocytes and the results of measurements on animal and vegetal oocyte halves from control and mature oocytes showed no evidence of a redistribution of calmodulin during maturation. Measurements of calmodulin synthesis in stages 1 and 2 oocytes, stage 4 oocytes, and stage 6 oocytes indicated that calmodulin was being synthesized continuously during oogenesis and that the rate of synthesis increased during oogenesis. In stage 1 and 2 oocytes (combined), the synthesis rate was 3.5 pg/hr/oocyte; in stage 4 oocytes it was 48 pg/hr/oocyte, and in large stage 6 oocytes the rate had increased to 160 pg/hr/oocyte. These changes in the rates of synthesis were discussed as they relate to the pattern of calmodulin accumulation during oogenesis.
M F
MF
Cicirelli
L D
LD
Smith
D000818:Animals; D002118:Calcium / Q000378:metabolism; D002147:Calmodulin / Q000032:analysis / Q000096:biosynthesis* / Q000378:metabolism; D005260:Female; D009865:Oocytes / Q000032:analysis / Q000378:metabolism / Q000502:physiology*; D009866:Oogenesis; D011061:Poly A / Q000096:biosynthesis; D014176:Protein Biosynthesis; D012313:RNA / Q000096:biosynthesis; D012333:RNA, Messenger; D014982:Xenopus laevis
D002147:Calmodulin; D012333:RNA, Messenger; D011061:Poly A; D012313:RNA; D002118:Calcium