Ramadan, Kristijan; Bruderer, Roland; Spiga, Fabio M.; Popp, Oliver; Baur, Tina; Gotta, Monica; Meyer, Hemmo:

Cdc48/p97 promotes reformation of the nucleus by extracting the kinase Aurora B from chromatin

In: Nature, Jg. 450 (2007) ; Nr. 7173, S. 1258
ISSN: 0028-0836
Zeitschriftenaufsatz / Fach: Biologie
Fakultät für Biologie » Chemische Biologie
Abstract:
During division of metazoan cells, the nucleus disassembles to allow
   chromosome segregation, and then reforms in each daughter cell.
   Reformation of the nucleus involves chromatin decondensation and
   assembly of the double- membrane nuclear envelope around the chromatin;
   however, regulation of the process is still poorly understood(1,2). In
   vitro, nucleus formation requires p97 ( ref. 3), a hexameric ATPase
   implicated in membrane fusion and ubiquitin- dependent processes(4,5).
   However, the role and relevance of p97 in nucleus formation have
   remained controversial. Here we show that p97 stimulates nucleus
   reformation by inactivating the chromatin- associated kinase Aurora B.
   During mitosis, Aurora B inhibits nucleus reformation by preventing
   chromosome decondensation and formation of the nuclear envelope
   membrane. During exit from mitosis, p97 binds to Aurora B after its
   ubiquitylation and extracts it from chromatin. This leads to
   inactivation of Aurora B on chromatin, thus allowing chromatin
   decondensation and nuclear envelope formation. These data reveal an
   essential pathway that regulates reformation of the nucleus after
   mitosis and defines ubiquitin- dependent protein extraction as a common
   mechanism of Cdc48/p97 activity also during nucleus formation.