Article

Regulation of the anaphase-promoting complex by the COP9 signalosome.

Core Unit Chip Application, Institute of Human Genetics and Anthropology, Jena University Hospital, Jena, Germany.
Cell cycle (Georgetown, Tex.) (Impact Factor: 5.24). 08/2009; 8(13):2041-9.
Source: PubMed

ABSTRACT The COP9 complex (signalosome) is a known regulator of the proteasome/ubiquitin pathway. Furthermore it regulates the activity of the cullin-RING ligase (CRL) families of ubiquitin E3-complexes. Besides the CRL family, the anaphase-promoting complex (APC/C) is a major regulator of the cell cycle. To investigate a possible connection between both complexes we assessed interacting partners of COP9 using an in vivo protein-protein interaction assay. Hereby, we were able to show for the first time that CSN2, a subunit of the COP9 signalosome, interacts physically with APC/C. Furthermore, we detected a functional influence of the COP9 complex regarding the stability of several targets of the APC/C. Consistent with these data we showed a genetic instability of cells overexpressing CSN2.

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