Structural highlights
Function
[MLP3B_HUMAN] Involved in formation of autophagosomal vacuoles (autophagosomes). [SQSTM_MOUSE] Required both for the formation and autophagic degradation of polyubiquitin-containing bodies, called ALIS (aggresome-like induced structures). Links ALIS to the autophagic machinery via direct interaction with MAP1 LC3 family members. May regulate the activation of NFKB1 by TNF-alpha, nerve growth factor (NGF) and interleukin-1. May play a role in titin/TTN downstream signaling in muscle cells. May regulate signaling cascades through ubiquitination. May be involved in cell differentiation, apoptosis, immune response and regulation of K(+) channels. Adapter that mediates the interaction between TRAF6 and CYLD.[1] [2]
Evolutionary Conservation
Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.
Publication Abstract from PubMed
Impairment of autophagic degradation of the ubiquitin- and LC3-binding protein "p62" leads to the formation of cytoplasmic inclusion bodies. However, little is known about the sorting mechanism of p62 to autophagic degradation. Here we identified a motif of murine p62 consisting of 11 amino acids (Ser334-Ser344) containing conserved acidic and hydrophobic residues across species, as an LC3 recognition sequence (LRS). The crystal structure of the LC3-LRS complex at 1.56 angstroms resolution revealed interaction of Trp340 and Leu343 of p62 with different hydrophobic pockets on the ubiquitin fold of LC3. In vivo analyses demonstrated that p62 mutants lacking LC3 binding ability accumulated without entrapping into autophagosomes in the cytoplasm and subsequently formed ubiquitin-positive inclusion bodies as in autophagy-deficient cells. These results demonstrate that the intracellular level of p62 is tightly regulated by autophagy through the direct interaction of LC3 with p62 and reveal that selective turnover of p62 via autophagy controls inclusion body formation.
Structural basis for sorting mechanism of p62 in selective autophagy.,Ichimura Y, Kumanomidou T, Sou YS, Mizushima T, Ezaki J, Ueno T, Kominami E, Yamane T, Tanaka K, Komatsu M J Biol Chem. 2008 Aug 15;283(33):22847-57. Epub 2008 Jun 4. PMID:18524774[3]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Duran A, Serrano M, Leitges M, Flores JM, Picard S, Brown JP, Moscat J, Diaz-Meco MT. The atypical PKC-interacting protein p62 is an important mediator of RANK-activated osteoclastogenesis. Dev Cell. 2004 Feb;6(2):303-9. PMID:14960283
- ↑ Jin W, Chang M, Paul EM, Babu G, Lee AJ, Reiley W, Wright A, Zhang M, You J, Sun SC. Deubiquitinating enzyme CYLD negatively regulates RANK signaling and osteoclastogenesis in mice. J Clin Invest. 2008 May;118(5):1858-66. doi: 10.1172/JCI34257. PMID:18382763 doi:10.1172/JCI34257
- ↑ Ichimura Y, Kumanomidou T, Sou YS, Mizushima T, Ezaki J, Ueno T, Kominami E, Yamane T, Tanaka K, Komatsu M. Structural basis for sorting mechanism of p62 in selective autophagy. J Biol Chem. 2008 Aug 15;283(33):22847-57. Epub 2008 Jun 4. PMID:18524774 doi:http://dx.doi.org/M802182200
