If You Use a Screen ReaderThis content is available through Read Online (Free) program, which relies on page scans. Since scans are not currently available to screen readers, please contact JSTOR User Support for access. We'll provide a PDF copy for your screen reader.
Induction of Maturation (Meiosis) in Small Xenopus laevis Oocytes by Injection of Maturation Promoting Factor
J. Hanocq-Quertier, E. Baltus and J. Brachet
Proceedings of the National Academy of Sciences of the United States of America
Vol. 73, No. 6 (Jun., 1976), pp. 2028-2032
Published by: National Academy of Sciences
Stable URL: https://www.jstor.org/stable/65611
Page Count: 5
You can always find the topics here!Topics: Oocytes, Protein synthesis, Chromosomes, Condensation, Animals, Embryogenesis, DNA, Mitotic spindle apparatus, Pituitary hormones
Were these topics helpful?
Select the topics that are inaccurate.
Since scans are not currently available to screen readers, please contact JSTOR User Support for access. We'll provide a PDF copy for your screen reader.
Preview not available
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 mm 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.
Proceedings of the National Academy of Sciences of the United States of America © 1976 National Academy of Sciences