The membrane peroxin PEX3 induces peroxisome-ubiquitination-linked pexophagy

Proliferation and fission of peroxisomes — An update

“…Protein ubiquitination has been shown to influence peroxisome protein import and autophagy by targeting Pex5: mono-ubiquitination at Cys11 leads to recycling of the PTS1-import receptor from the peroxisomal membrane back into the cytosol whilst poly-ubiquitination marks peroxisomes for degradation by autophagy [42]. In addition, ubiquitination of other peroxins has been described to influence protein import and degradation of peroxisomes [56,95,184,188] (see Chapter by Platta & Eggeling, this issue). Interestingly, the ubiquitinatable Cys11/10 of Pex5 was shown to be redox-sensitive in humans and P. pastoris [98,113].…”

Peroxisomal Pex3 Activates Selective Autophagy of Peroxisomes via Interaction with the Pexophagy Receptor Atg30

“…Pex3 regulates peroxisome biogenesis by acting as a docking factor for Pex19, the protein that recognizes the membrane PTS on PMPs and facilitates their post-transla-tional insertion into the peroxisomal membrane (20 -23); as a tether for the peroxisome inheritance factor Inp1 (24,25); as the receptor for Myo2 for peroxisome segregation in Yarrowia lipolytica (26); and as an anchor at the peroxisomal membrane for P. pastoris Atg30 and S. cerevisiae Atg36 (10,16). Additionally, Pex3 has been implicated in pexophagy in other species, such as the methylotrophic yeast Hansenula polymorpha, in which removal of ubiquitinated Pex3 from the peroxisomal membrane induces pexophagy, and in mammals, in which Pex3 overexpression induces pexophagy through a ubiquitin-dependent mechanism (27,28).…”

Molecular Mechanisms and Physiological Significance of Organelle Interactions and Cooperation

“…Overexpression of Pex3 in CHO cells and mouse embryonic fibroblasts induced clustering of peroxisomes and NBR1-mediated pexophagy, albeit no direct interaction between PEX3 and NBR1 could be detected (Yamashita et al, 2014). Interestingly, ubiquitin signals were observed on peroxisomes upon Pex3 overexpression, suggesting that a currently unidentified PMP is ubiquitinated in PEX3-mediated pexophagy and might function in NBR1 recruitment (Yamashita et al, 2014).…”

“…Interestingly, ubiquitin signals were observed on peroxisomes upon Pex3 overexpression, suggesting that a currently unidentified PMP is ubiquitinated in PEX3-mediated pexophagy and might function in NBR1 recruitment (Yamashita et al, 2014).…”