Effect of phorbol ester PMA and puromycin on the maturation of mouse oocytes.
The effect of phorbol myristate acetate (PMA) and puromycin (PU) on maturation divisions of mouse oocytes was investigated. PMA changed the morphology and function of the spindle in meiosis I. The spindle had a broad polar region and did not commence karyokinesis in the first maturation division. This persisted in 25% of spindles which were passive up to 30 h of maturation. Half of the oocytes with spindles blocked by PMA between 20 and 30 h of maturation became activated, and 25% of the initial pool underwent abortive karyokinesis consisting of segregation of several chromosomes of the metaphase plate. Cytological observation indicated that the presence of PMA interfered with the elongation of the spindle in anaphase. Under the condition of changed phosphorylation of maturation of proteins by PMA, a reversible interphase was induced by PU. Most of the nuclei induced by PU exhibited pronuclei. A new class of nuclei induced by PU with condensed chromatin and having no nucleoli is described. The mechanism and consequences of interference of PMA on anaphase are discussed.
Niemierko
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Laboratory of Experimental Embryology, Medical Academy, Warsaw, Poland.
Komar
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D000818:Animals; D005260:Female; D008540:Meiosis / Q000187:drug effects; D051379:Mice; D008810:Mice, Inbred C57BL; D008808:Mice, Inbred CBA; D009865:Oocytes / Q000187:drug effects / Q000254:growth & development*; D011691:Puromycin / Q000494:pharmacology*; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology*
D011691:Puromycin; D013755:Tetradecanoylphorbol Acetate