Original title:
Aurora-A is involved in resumption of meiosis and spindle formation in mouse oocytes
Translated title:
Aurora-A je zhrnuta v znovuzahájení meiosy a formaci metafáze I spindlu
Authors:
Šašková, Adéla ; Šolc, Petr ; Baran, V. ; Kubelka, Michal ; Motlík, Jan Document type: Papers Conference/Event: Cytoskeletální klub /XV./, Vranovská Ves (CZ), 2007-05-09 / 2007-05-11
Year:
2007
Language:
eng Abstract:
[eng][cze] We study the role of Aurora-A during meiotic maturation of mouse oocytes. Total Aurora-A is present in the nucleus in GV-stage oocytes (G2 equivalent). Additionally, active Aurora-A is localized entirely to the centrosome (MTOC) shorly before germinal vesicle breakdown (GVBD). Compared to somatic cells, where active Aurora-A is at the centrosomes and the spindle poles, active Aurora-A is strictly localized on MTOCs at metaphase I in oocytes. We show that activation of centrosomal Aurora-A is independent on PI3K-PKB and CDK1 signaling pathways. This was proved by cultivation of oocytes in presence of roscovitine (CDK1 inhibitor), LY-294002 (PI3K inhibitor) and SH-6 (PKB inhibitor). Treated oocytes show high phosphorylation of Aurora-A on T288 and centrosome amplification despite the presence of intact nuclear envelope. Silencing of Aurora-A by RNA interference induces incorrect spindle assembly. Oocytes are arrested in prometaphase I and unable to reach metaphase II. After microinjection of eGFP-Aurora-A mRNA into GV-stage oocytes, overexpression of Aurora-A leads to distortion of MI spindle organization as well. Our results indicate that Aurora-A is the key centrosomal player in meiotic maturation, essential for proper spindle formation and metaphase I - metaphase II transition.Práce se zabývá úlohou Aurora-A kinázy během meiotického zrání in vitro. Pomocí farmakologické inhibice PI3K, PKB a CDK1 bylo prokázáno, že Aurora-A, se aktivuje velmi časně při znovuzahájení meiosy, a toto aktivace je nezávislá na PI3K-PKB a CDK1 signalizaci. Dále bylo prokázáno (RNA interference, mikroinjekce mRNA), že Aurora-A je nutná pro korektní výstavbu metafáze I spindelu a pro metafase I – metafase II přechod.
Keywords:
meiosis Project no.: CEZ:AV0Z50450515 (CEP) Host item entry: XV. cytoskeletální klub
Institution: Institute of Animal Physiology and Genetics AS ČR
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Document availability information: Fulltext is available at the institute of the Academy of Sciences. Original record: http://hdl.handle.net/11104/0150547