Journal article
Maturation induced internalization of Beta(1)-Integrin by xenopus-occyties and formation of the maternal integrin pool



Publication Details
Authors:
Müller, H.; Gawantka, V.; Ding, X.; Hausen, P.
Publisher:
ELSEVIER SCIENCE BV
Publication year:
1993
Journal:
Mechanisms of Development
Pages range:
77-88
Volume number:
42
Issue number:
1-2
Start page:
77
End page:
88
Number of pages:
12
ISSN:
0925-4773

Abstract
A pool of beta1-integrin, ready to be inserted into the cleavage membranes, is present in the cytoplasm of the Xenopus egg, while its plasma membrane is devoid of this membrane protein (Gawantka et al., 1992). The underlying mechanisms that lead to this specific pattern of beta1-integrin distribution in the egg have been investigated. beta1-Integrin is present on the oocyte membrane throughout oogenesis. During maturation the oocyte membrane is cleared of beta1-integrin via internalization of the protein by the oocyte. Synthesis of beta1-integrin precursor is stimulated moderately in the maturing oocyte. At the same time processing of the precursor into the mature form of beta1-integrin and its complexing with a putative alpha-chain is greatly accelerated. This way a maternal integrin pool accumulates in the mature oocyte. It is localized in conspicuous yolk free patches which contain large amounts of endoplasmic reticulum, Golgi complexes and smooth vesicles. We suggest that membrane vesicles harbouring the beta1-integrin are generated in these cytoplasmic regions and that this store of vesicles provides the material source for the rapid membrane formation during cleavage.


Keywords
BETA(1)-INTEGRIN, OOCYTE MATURATION, oogenesis, XENOPUS


Authors/Editors

Last updated on 2019-25-07 at 15:07

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