Structural Basis of Tail-Anchored Membrane Protein Biogenesis by the GET 
Insertase Complex

McDowell, Melanie A.; Heimes, Michael; Fiorentino, Francesco; Mehmood, Shahid; Farkas, Ákos; Coy-Vergara, Javier; Wu, Di; Bolla, Jani Reddy; Schmid, Volker; Heinze, Roger; Wild, Klemens; Flemming, Dirk; Pfeffer, Stefan; Schwappach, Blanche; Robinson, Carol V.; Sinning, Irmgard

doi:10.1016/j.molcel.2020.08.012

Item

ITEM ACTIONSEXPORT

Add to Basket

Local TagsRelease HistoryDetailsSummary

Released

Journal Article

Structural Basis of Tail-Anchored Membrane Protein Biogenesis by the GET Insertase Complex

MPS-Authors

There are no MPG-Authors in the publication available

External Resource

No external resources are shared

Fulltext (restricted access)

There are currently no full texts shared for your IP range.

Fulltext (public)

There are no public fulltexts stored in PuRe

Supplementary Material (public)

There is no public supplementary material available

Citation

McDowell, M. A., Heimes, M., Fiorentino, F., Mehmood, S., Farkas, Á., Coy-Vergara, J., et al. (2020). Structural Basis of Tail-Anchored Membrane Protein Biogenesis by the GET Insertase Complex. Molecular Cell, 80(1), 72-86. doi:10.1016/j.molcel.2020.08.012.

Cite as: https://hdl.handle.net/21.11116/0000-0009-598E-4

Abstract

Membrane protein biogenesis faces the challenge of chaperoning hydrophobic transmembrane helices for faithful membrane insertion. The guided entry of tail-anchored proteins (GET) pathway targets and inserts tail-anchored (TA) proteins into the endoplasmic reticulum (ER) membrane with an insertase (yeast Get1/Get2 or mammalian WRB/CAML) that captures the TA from a cytoplasmic chaperone (Get3 or TRC40, respectively). Here, we present cryo-electron microscopy reconstructions, native mass spectrometry, and structure-based mutagenesis of human WRB/CAML/TRC40 and yeast Get1/Get2/Get3 complexes. Get3 binding to the membrane insertase supports heterotetramer formation, and phosphatidylinositol binding at the heterotetramer interface stabilizes the insertase for efficient TA insertion in vivo. We identify a Get2/CAML cytoplasmic helix that forms a "gating" interaction with Get3/TRC40 important for TA insertion. Structural homology with YidC and the ER membrane protein complex (EMC) implicates an evolutionarily conserved insertion mechanism for divergent substrates utilizing a hydrophilic groove. Thus, we provide a detailed structural and mechanistic framework to understand TA membrane insertion.