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Ubiquitin acetylation inhibits polyubiquitin chain elongation.

ABSTRACT: Ubiquitylation is a versatile post-translational modification (PTM). The diversity of ubiquitylation topologies, which encompasses different chain lengths and linkages, underlies its widespread cellular roles. Here, we show that endogenous ubiquitin is acetylated at lysine (K)-6 (AcK6) or K48. Acetylated ubiquitin does not affect substrate monoubiquitylation, but inhibits K11-, K48-, and K63-linked polyubiquitin chain elongation by several E2 enzymes in vitro. In cells, AcK6-mimetic ubiquitin stabilizes the monoubiquitylation of histone H2B-which we identify as an endogenous substrate of acetylated ubiquitin-and of artificial ubiquitin fusion degradation substrates. These results characterize a mechanism whereby ubiquitin, itself a PTM, is subject to another PTM to modulate mono- and polyubiquitylation, thus adding a new regulatory layer to ubiquitin biology.

SUBMITTER: Ohtake F

PROVIDER: S-EPMC4328746 | biostudies-literature | 2015 Feb

REPOSITORIES: biostudies-literature

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Ubiquitin acetylation inhibits polyubiquitin chain elongation.

Ohtake Fumiaki F Saeki Yasushi Y Sakamoto Kensaku K Ohtake Kazumasa K Nishikawa Hiroyuki H Tsuchiya Hikaru H Ohta Tomohiko T Tanaka Keiji K Kanno Jun J

EMBO reports 20141219 2

Ubiquitylation is a versatile post-translational modification (PTM). The diversity of ubiquitylation topologies, which encompasses different chain lengths and linkages, underlies its widespread cellular roles. Here, we show that endogenous ubiquitin is acetylated at lysine (K)-6 (AcK6) or K48. Acetylated ubiquitin does not affect substrate monoubiquitylation, but inhibits K11-, K48-, and K63-linked polyubiquitin chain elongation by several E2 enzymes in vitro. In cells, AcK6-mimetic ubiquitin st ...[more]

PMID: 25527407

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