Abstract:
:Nuclear structural changes during fertilization and embryogenesis in mice and in sea urchins have been followed by using antibodies against the nuclear lamins A/C and B and against antigens at the periphery of nuclei and chromosomes. Lamins are found on all pronuclei and nuclei during mouse fertilization, but with a diminished intensity on the second polar body nucleus. On sperm in both systems, lamins are reduced and detected only at the acrosomal and centriolar fossae. In sea urchin eggs, lamins are found on both pronuclei. Unlike in other dividing cells, the mitotic chromosomes of sea urchin eggs and embryos retain an association with lamins. The peripheral antibodies delineate each chromosome and nucleus except the mature mouse sperm nucleus. A dramatic change from the expected lamin distribution occurs during early development. In mouse morulae or blastocysts, lamins A/C are no longer recognized, although lamin B remains. In sea urchins both lamins A/C and lamin B, as detected with polyclonal antibodies, are lost after the blastula stage, although a different lamin A/C epitope emerges as recognized by a monoclonal antibody. These results demonstrate that pronucleus formation in both systems involves a new association or exposure of lamins, that the polar body nucleus is largely restricted from the cytoplasmic pool of lamins, and that mitotic chromosomes in the rapidly proliferating sea urchin egg retain associated lamins. They also suggest that changes in the expression or exposure of different lamins are a common feature of embryogenesis.
journal_name
Proc Natl Acad Sci U S Aauthors
Schatten G,Maul GG,Schatten H,Chaly N,Simerly C,Balczon R,Brown DLdoi
10.1073/pnas.82.14.4727subject
Has Abstractpub_date
1985-07-01 00:00:00pages
4727-31issue
14eissn
0027-8424issn
1091-6490journal_volume
82pub_type
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:2009-02-17 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:2007-06-12 00:00:00
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更新日期:2010-12-28 00:00:00