title: The GET System Inserts the Tail-Anchored Protein, SYP72, into Endoplasmic Reticulum Membranes.
abstract: The Arabidopsis (Arabidopsis thaliana) genome encodes homologs of the Guided Entry of Tail (GET)-anchored protein system for the posttranslational insertion of tail-anchored (TA) proteins into endoplasmic reticulum (ER) membranes. In yeast, TA proteins are loaded onto the cytosolic targeting factor Get3 and are then delivered to the membrane-associated Get1/2 complex for insertion into ER membranes. The role of the GET system in Arabidopsis was investigated by monitoring the membrane insertion of a tail-anchored protein, SYP72, a syntaxin. SYP72 bound to yeast Get3 in vitro, forming a Get3-SYP72 fusion complex that could be inserted into yeast GET1/2-containing proteoliposomes. The Arabidopsis GET system functioned in vivo to insert TA proteins into ER membranes as demonstrated by the fact that the YFP-tagged SYP72 localized to the ER in wild-type plants but accumulated as cytoplasmic inclusions in get1, get3, or get4 mutants. The GET mutants get1 and get3 were less tolerant of ER stress agents and showed symptoms of ER stress even under unstressed conditions. Hence, the GET system is responsible for the insertion of TA proteins into the ER in Arabidopsis, and mutants with GET dysfunctions are more susceptible to ER stress.
authors.affiliation: Plant Sciences Institute and Department of Genetics, Development, and Cell Biology, Iowa State University, Ames, Iowa 50010 (R.S., S.H.H.); and.|Department of Biochemistry and Molecular Biology, The University of Chicago, Chicago, Illinois 60637 (B.E.Z., R.J.K.).
authors.forename: Renu
authors.identifier: 0000-0001-5464-1493
authors.initials: R
authors.lastname: Srivastava
authors.affiliation: Plant Sciences Institute and Department of Genetics, Development, and Cell Biology, Iowa State University, Ames, Iowa 50010 (R.S., S.H.H.); and.|Department of Biochemistry and Molecular Biology, The University of Chicago, Chicago, Illinois 60637 (B.E.Z., R.J.K.).
authors.forename: Benjamin E
authors.initials: BE
authors.lastname: Zalisko
authors.affiliation: Plant Sciences Institute and Department of Genetics, Development, and Cell Biology, Iowa State University, Ames, Iowa 50010 (R.S., S.H.H.); and.|Department of Biochemistry and Molecular Biology, The University of Chicago, Chicago, Illinois 60637 (B.E.Z., R.J.K.).
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Keenan
authors.affiliation: Plant Sciences Institute and Department of Genetics, Development, and Cell Biology, Iowa State University, Ames, Iowa 50010 (R.S., S.H.H.); and shh@iastate.edu.|Department of Biochemistry and Molecular Biology, The University of Chicago, Chicago, Illinois 60637 (B.E.Z., R.J.K.) shh@iastate.edu.
authors.forename: Stephen H
authors.identifier: 0000-0001-5863-2527
authors.initials: SH
authors.lastname: Howell
mesh_terms: D017360:Arabidopsis / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000378:metabolism*; D004721:Endoplasmic Reticulum / Q000378:metabolism*; D007425:Intracellular Membranes / Q000378:metabolism*; D009154:Mutation / Q000235:genetics; D010641:Phenotype; D011510:Proteolipids / Q000378:metabolism; D050765:Qa-SNARE Proteins / Q000378:metabolism*; D017386:Sequence Homology, Amino Acid; D013347:Subcellular Fractions / Q000378:metabolism; D013379:Substrate Specificity
chemical_list: D029681:Arabidopsis Proteins; D011510:Proteolipids; D050765:Qa-SNARE Proteins; C000622999:SYP72 protein, Arabidopsis; C020485:proteoliposomes