Nuclear envelope disassembly and nuclear lamina depolymerization during germinal vesicle breakdown in starfish.

S A Stricker; G Schatten

doi:10.1016/0012-1606(89)90160-7

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Nuclear envelope disassembly and nuclear lamina depolymerization during germinal vesicle breakdown in starfish.

S A Stricker·G Schatten

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Abstract

During germinal vesicle breakdown (GVBD) in starfish, the nuclear envelope disassembles before the nuclear lamina completely depolymerizes, judging from correlative ultrastructural, immunolabeling, and light microscopic analyses. At 13 degrees C, prophase-arrested oocytes of Pisaster ochraceus begin GVBD and rapidly undergo nuclear envelope disassembly about 50 min after addition of the maturation-inducing hormone 1-methyladenine (1-MA). The nuclear lamina of these oocytes, however, remains present for 10-20 min following the vesiculation of the nuclear envelope. Completion of GVBD, as evidenced by a blending of the nuclear contents with the surrounding cytoplasm, occurs within about 15 min after the nuclear lamina has fully depolymerized. Immunofluorescence studies also indicate that a marked increase in the phosphorylations of nuclear proteins precedes the structural reorganizations of the nuclear envelope and nuclear lamina during GVBD.

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Adenine Animals Fluorescent Antibody Technique Meiosis Microscopy, Electron Microscopy, Electron, Scanning Nuclear Envelope Nuclear Proteins Oogenesis Ovum Phosphoproteins Phosphorylation Starfish Video Recording Journal Article Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, P.H.S.

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S A Stricker, G Schatten. 1989. Nuclear envelope disassembly and nuclear lamina depolymerization during germinal vesicle breakdown in starfish.. https://doi.org/10.1016/0012-1606(89)90160-7

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