Induction of maturation (meiosis) in small Xenopus laevis oocytes by injection of maturation promoting factor.
AUTOR(ES)
Hanocq-Quertier, J
RESUMO
Treatment of small-(stage III) or medium-sized (stage IV) Xenopus laevis oocytes with progesterone, human chorionic gonadotropin, or para-hydroxymercuriphenylsulfonate does not induce maturation. Only the full-grown oocytes (stage VI) undergo maturation when treated with either one of these three substances. In contrast, injection of maturation promoting factor into oocytes of stages III-VI invariably leads to chromosome condensation and germinal vesicle breakdown. No maturation spindle is found in oocytes smaller than 0.9 nm in diameter, and the nuclear sap does not mix with the cytoplasm in the smallest (0.45-0.55 mm in diameter) oocytes. In oocytes of 0.9 mm, maturation is identical to that of full-grown oocytes, except that the maturation spindle does not reach the cortex of the oocyte. Progesterone increases protein synthesis in medium-sized (0.8 mm in diameter) oocytes without inducing meiosis. It has little or no effect on protein synthesis in smaller oocytes.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=430441Documentos Relacionados
- Induction of maturation (meiosis) in Xenopus laevis oocytes by three organomercurials.
- Ionic requirements for induction of maturation (meiosis) in full-grown and medium-sized Xenopus laevis oocytes.
- Induction of maturation in Xenopus laevis oocytes by a steroid linked to a polymer
- tpr-met Oncogene Product Induces Maturation-Promoting Factor Activation in Xenopus Oocytes
- Microinjected progesterone reinitiates meiotic maturation of Xenopus laevis oocytes.