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A conserved archaeal pathway for tail-anchored membrane protein insertion.

ABSTRACT: Eukaryotic tail-anchored (TA) membrane proteins are inserted into the endoplasmic reticulum by a post-translational TRC40 pathway, but no comparable pathway is known in other domains of life. The crystal structure of an archaebacterial TRC40 sequence homolog bound to ADP•AlF(4) (-) reveals characteristic features of eukaryotic TRC40, including a zinc-mediated dimer and a large hydrophobic groove. Moreover, archaeal TRC40 interacts with the transmembrane domain of TA substrates and directs their membrane insertion. Thus, the TRC40 pathway is more broadly conserved than previously recognized.

SUBMITTER: Sherrill J

PROVIDER: S-EPMC3155638 | biostudies-literature | 2011 Sep

REPOSITORIES: biostudies-literature

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A conserved archaeal pathway for tail-anchored membrane protein insertion.

Sherrill John J Mariappan Malaiyalam M Dominik Pawel P Hegde Ramanujan S RS Keenan Robert J RJ

Traffic (Copenhagen, Denmark) 20110703 9

Eukaryotic tail-anchored (TA) membrane proteins are inserted into the endoplasmic reticulum by a post-translational TRC40 pathway, but no comparable pathway is known in other domains of life. The crystal structure of an archaebacterial TRC40 sequence homolog bound to ADP•AlF(4) (-) reveals characteristic features of eukaryotic TRC40, including a zinc-mediated dimer and a large hydrophobic groove. Moreover, archaeal TRC40 interacts with the transmembrane domain of TA substrates and directs their ...[more]

PMID: 21658170

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