Meiotic breakdown of nuclear envelope in oocytes of Spisula solidissima involves phosphorylation and release of nuclear lamin.
During meiotic nuclear envelope breakdown (NEBD) in maturing oocytes of the surf clam, Spisula solidissima, the 67-kDa lamin is extensively phosphorylated, concurrently with its solubilization. This is accompanied by a reduction of the nuclear diameter. Quercetin, a protein kinase inhibitor, does not affect lamin phosphorylation and release, nor NEBD per se, but specifically inhibits the early phosphorylation of a set of proteins, on which NEBD seems to depend. Our results suggest that meiotic NEBD in Spisula oocytes may be controlled by a mechanism which involves lamin phosphorylation, similar to that which is thought to operate in mitosis.
Dessev
G
G
Department of Cell Biology and Anatomy, Northwestern University Medical School, Chicago, Illinois 60611.
Goldman
R
R
D000818:Animals; D049872:Bivalvia; D015180:Electrophoresis, Gel, Two-Dimensional; D007158:Immunologic Techniques; D007526:Isoelectric Point; D034882:Lamins; D008540:Meiosis; D008970:Molecular Weight; D009685:Nuclear Envelope / Q000502:physiology*; D009687:Nuclear Proteins / Q000502:physiology*; D009865:Oocytes / Q000502:physiology*; D010750:Phosphoproteins / Q000378:metabolism; D010766:Phosphorylation; D011794:Quercetin / Q000494:pharmacology; D012995:Solubility
D034882:Lamins; D009687:Nuclear Proteins; D010750:Phosphoproteins; D011794:Quercetin