Anaphase promoting complex

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The anaphase-promoting complex / cyclosome ( APC / C ) - the anaphase- promoting complex or the cyclosome - is an enzyme complex that occurs in the cell nuclei of all eukaryotes . The complex consists of a good dozen subunits, several of which have the enzyme activity of ubiquitin ligases . With these subunits , the complex catalyzes the binding of one or more ubiquitin molecules to several regulatory proteins , which marks them for enzymatic protein degradation ( proteolysis ) in the proteasome . The best-known substrates of APC / C include cyclin-A , cyclin-B and securin , to which ubiquitin is attached in a strictly timed sequence during mitosis , whereby they are finally broken down. APC / C is thus the main molecular regulator for the timing of mitosis, or its G1 phase and the chromosome separation .

In the event of an infection with the human cytomegalovirus , the cell cycle is permanently disrupted by inactivation of the APC / C.

In humans, the following proteins belong to APC / C: APC1, APC2, APC3 ( CDC27 ), APC4, APC5, APC6 ( CDC16 ), APC7, APC8 ( CDC23 ), APC10, APC11, APC12 ( CDC26 ), APC13, APC15, APC16.

In addition to the main subunits of the complex, the APC / C requires the proteins MAD2L1 and CDC20 in order to achieve the optimal enzyme activity and substrate specificity . Formally, however, these no longer belong to the complex.

Individual evidence

  1. ↑ JM Peters: Subunits and substrates of the anaphase-promoting complex. In: Experimental Cell Research . Volume 248, Number 2, May 1999, pp. 339-349, ISSN  0014-4827 . doi : 10.1006 / excr.1999.4443 . PMID 10222126 . (Review).
  2. ↑ K. Tran, JA Mahr u. a .: Accumulation of substrates of the anaphase-promoting complex (APC) during human cytomegalovirus infection is associated with the phosphorylation of Cdh1 and the dissociation and relocalization of APC subunits. In: Journal of virology. Volume 82, Number 1, January 2008, pp. 529-537, ISSN  1098-5514 . doi : 10.1128 / JVI.02010-07 . PMID 17942546 . PMC 2224378 (free full text).
  3. ↑ UniProt Q12834

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