Unique requirements for mono-and polyubiquitination of the peroxisomal targeting signal co-receptor, Pex20

Abstract

Background: Pex20 recycling and degradation depend on its ubiquitination. Results: Ubiquitination of Pex20 and the roles of the E2 enzyme Pex4, the RING peroxins (Pex2/Pex10/Pex12), and Pex7 in Pex20 ubiquitination were determined in vivo. Conclusion: The RING peroxins and Pex4 are required for Pex20 mono/polyubiquitination, whereas Pex7 is only required for its polyubiquitination. Significance: This novel mechanism of ubiquitination is not used by other PTS receptors. © 2013 by The American Society for Biochemistry and Molecular Biology, Inc.