Editing Anaphase-promoting complex (section)

{{Short description|Cell-cycle regulatory complex}}
{{about|the cell-cycle regulatory complex, APC/C|the tumor suppressor APC, in which mutations lead to colon cancer|Adenomatous polyposis coli}}

[[File:The anaphase-promoting complex (APC).pdf|thumb|The anaphase-promoting complex (APC) is a large protein complex containing 11–13 subunits, including a RING subunit (Apc11) and a cullin (Apc2). APC activity requires association with activator subunits (Cdc20 or Cdh1) that contribute to substrate binding.]]

'''Anaphase-promoting complex''' (also called the '''cyclosome''' or '''APC/C''') is an E3 [[ubiquitin ligase]] that marks target [[cell cycle]] proteins for degradation by the 26S [[proteasome]].  The APC/C is a large complex of 11–13 subunit [[protein]]s, including a [[cullin]] ([[ANAPC2|Apc2]]) and [[RING]] ([[ANAPC11|Apc11]]) subunit much like [[SCF complex|SCF]].  Other parts of the APC/C have unknown functions but are highly [[Conserved sequence|conserved]].<ref name= "Morgan_2007">{{cite book | vauthors = Morgan DO | chapter = Chapter 3-10: The Anaphase Promoting Complex |title=The Cell Cycle: Principles of Control |publisher=New Science Press |location=London |year=2007 |isbn=978-0-9539181-2-6 | pages = 48–49 | chapter-url = https://books.google.com/books?id=ScEuiD2V6GoC&q=978-0-9539181-2-6&pg=PA48}}</ref>

It was the discovery of the APC/C (and [[SCF complex|SCF]]) and their key role in eukaryotic cell-cycle regulation that established the importance of [[ubiquitin]]-mediated [[proteolysis]] in cell biology. Once perceived as a system exclusively involved in removing damaged protein from the cell, ubiquitination and subsequent protein degradation by the [[proteasome]] is now perceived as a universal regulatory mechanism for [[signal transduction]] whose importance approaches that of [[protein phosphorylation]].

In 2014, the APC/C was mapped in 3D at a resolution of less than a [[nanometre]], which also uncovered its secondary structure. This finding could improve understanding of [[cancer]] and reveal new binding sites for future cancer drugs.<ref>{{cite web |title=Scientists map one of most important proteins in life – and cancer |url=https://www.icr.ac.uk/news-archive/scientists-map-one-of-most-important-proteins-in-life-and-cancer |work=The Institute of Cancer Research |date=20 July 2014 |access-date=22 July 2014 }}</ref><ref>{{cite journal | vauthors = Chang LF, Zhang Z, Yang J, McLaughlin SH, Barford D | title = Molecular architecture and mechanism of the anaphase-promoting complex | journal = Nature | volume = 513 | issue = 7518 | pages = 388–393 | date = September 2014 | pmid = 25043029 | pmc = 4456660 | doi = 10.1038/nature13543 | bibcode = 2014Natur.513..388C }}</ref>