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Tail-Anchored Protein Insertion by a Single Get1/2 Heterodimer.

ABSTRACT: The Get1/2 transmembrane complex drives the insertion of tail-anchored (TA) proteins from the cytosolic chaperone Get3 into the endoplasmic reticulum membrane. Mechanistic insight into how Get1/2 coordinates this process is confounded by a lack of understanding of the basic architecture of the complex. Here, we define the oligomeric state of full-length Get1/2 in reconstituted lipid bilayers by combining single-molecule and bulk fluorescence measurements with quantitative in vitro insertion analysis. We show that a single Get1/2 heterodimer is sufficient for insertion and demonstrate that the conserved cytosolic regions of Get1 and Get2 bind asymmetrically to opposing subunits of the Get3 homodimer. Altogether, our results define a simplified model for how Get1/2 and Get3 coordinate TA protein insertion.

SUBMITTER: Zalisko BE

PROVIDER: S-EPMC5657598 | biostudies-literature | 2017 Sep

REPOSITORIES: biostudies-literature

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Tail-Anchored Protein Insertion by a Single Get1/2 Heterodimer.

Zalisko Benjamin E BE Chan Charlene C Denic Vladimir V Rock Ronald S RS Keenan Robert J RJ

Cell reports 20170901 10

The Get1/2 transmembrane complex drives the insertion of tail-anchored (TA) proteins from the cytosolic chaperone Get3 into the endoplasmic reticulum membrane. Mechanistic insight into how Get1/2 coordinates this process is confounded by a lack of understanding of the basic architecture of the complex. Here, we define the oligomeric state of full-length Get1/2 in reconstituted lipid bilayers by combining single-molecule and bulk fluorescence measurements with quantitative in vitro insertion anal ...[more]

PMID: 28877464

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