title: Loss of GET pathway orthologs inArabidopsis thalianacauses root hair growth defects and affects SNARE abundance.
abstract: SolubleN-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) proteins are key players in cellular trafficking and coordinate vital cellular processes, such as cytokinesis, pathogen defense, and ion transport regulation. With few exceptions, SNAREs are tail-anchored (TA) proteins, bearing a C-terminal hydrophobic domain that is essential for their membrane integration. Recently, the Guided Entry of Tail-anchored proteins (GET) pathway was described in mammalian and yeast cells that serve as a blueprint of TA protein insertion [Schuldiner M, et al. (2008)Cell134(4):634-645; Stefanovic S, Hegde RS (2007)Cell128(6):1147-1159]. This pathway consists of six proteins, with the cytosolic ATPase GET3 chaperoning the newly synthesized TA protein posttranslationally from the ribosome to the endoplasmic reticulum (ER) membrane. Structural and biochemical insights confirmed the potential of pathway components to facilitate membrane insertion, but the physiological significance in multicellular organisms remains to be resolved. Our phylogenetic analysis of 37 GET3 orthologs from 18 different species revealed the presence of two different GET3 clades. We identified and analyzed GET pathway components inArabidopsis thalianaand found reduced root hair elongation inAtgetlines, possibly as a result of reduced SNARE biogenesis. Overexpression ofAtGET3a in a receptor knockout (KO) results in severe growth defects, suggesting presence of alternative insertion pathways while highlighting an intricate involvement for the GET pathway in cellular homeostasis of plants.
authors.affiliation: Centre for Plant Molecular Biology, Developmental Genetics, University of Tübingen, 72076 Tuebingen, Germany.
authors.forename: Shuping
authors.initials: S
authors.lastname: Xing
authors.affiliation: Centre for Plant Molecular Biology, Developmental Genetics, University of Tübingen, 72076 Tuebingen, Germany.
authors.forename: Dietmar Gerald
authors.initials: DG
authors.lastname: Mehlhorn
authors.affiliation: Centre for Plant Molecular Biology, Developmental Genetics, University of Tübingen, 72076 Tuebingen, Germany.
authors.forename: Niklas
authors.initials: N
authors.lastname: Wallmeroth
authors.affiliation: Centre for Plant Molecular Biology, Developmental Genetics, University of Tübingen, 72076 Tuebingen, Germany.
authors.forename: Lisa Yasmin
authors.initials: LY
authors.lastname: Asseck
authors.affiliation: Centre for Plant Molecular Biology, Developmental Genetics, University of Tübingen, 72076 Tuebingen, Germany.
authors.forename: Ritwika
authors.initials: R
authors.lastname: Kar
authors.affiliation: Centre for Plant Molecular Biology, Developmental Genetics, University of Tübingen, 72076 Tuebingen, Germany.
authors.forename: Alessa
authors.initials: A
authors.lastname: Voss
authors.affiliation: Centre for Organismal Studies, CellNetworks Excellence Cluster, University of Heidelberg, 69120 Heidelberg, Germany.
authors.forename: Philipp
authors.initials: P
authors.lastname: Denninger
authors.affiliation: Centre for Organismal Studies, CellNetworks Excellence Cluster, University of Heidelberg, 69120 Heidelberg, Germany.
authors.forename: Vanessa Aphaia Fiona
authors.initials: VA
authors.lastname: Schmidt
authors.affiliation: Institute of Crop Science and Resource Conservation, University of Bonn, 53113 Bonn, Germany.
authors.forename: Markus
authors.initials: M
authors.lastname: Schwarzländer
authors.affiliation: Centre for Plant Molecular Biology, Microscopy, University of Tübingen, 72076 Tuebingen, Germany.
authors.forename: York-Dieter
authors.initials: YD
authors.lastname: Stierhof
authors.affiliation: Centre for Organismal Studies, CellNetworks Excellence Cluster, University of Heidelberg, 69120 Heidelberg, Germany.
authors.forename: Guido
authors.identifier: 0000-0001-7529-9244
authors.initials: G
authors.lastname: Grossmann
authors.affiliation: Centre for Plant Molecular Biology, Developmental Genetics, University of Tübingen, 72076 Tuebingen, Germany; christopher.grefen@zmbp.uni-tuebingen.de.
authors.forename: Christopher
authors.identifier: 0000-0002-5820-4466
authors.initials: C
authors.lastname: Grefen
mesh_terms: D000251:Adenosine Triphosphatases / Q000378:metabolism; D000818:Animals; D017360:Arabidopsis / Q000502:physiology*; D029681:Arabidopsis Proteins / Q000378:metabolism*; D002462:Cell Membrane / Q000378:metabolism*; D003600:Cytosol / Q000378:metabolism; D004721:Endoplasmic Reticulum / Q000378:metabolism; D020662:Guanine Nucleotide Exchange Factors / Q000378:metabolism; D006706:Homeostasis / Q000502:physiology; D008322:Mammals / Q000502:physiology; D008561:Membrane Fusion / Q000502:physiology; D018832:Molecular Chaperones / Q000378:metabolism; D010802:Phylogeny; D018517:Plant Roots / Q000254:growth & development* / Q000378:metabolism; D030821:Plants, Genetically Modified; D050600:SNARE Proteins / Q000235:genetics / Q000378:metabolism*; D012441:Saccharomyces cerevisiae / Q000502:physiology; D029701:Saccharomyces cerevisiae Proteins / Q000378:metabolism; D015398:Signal Transduction / Q000502:physiology*; D052067:Soluble N-Ethylmaleimide-Sensitive Factor Attachment Proteins
chemical_list: D029681:Arabidopsis Proteins; D020662:Guanine Nucleotide Exchange Factors; D018832:Molecular Chaperones; D050600:SNARE Proteins; D029701:Saccharomyces cerevisiae Proteins; D052067:Soluble N-Ethylmaleimide-Sensitive Factor Attachment Proteins; D000251:Adenosine Triphosphatases; C529048:Get3 protein, S cerevisiae
keywords: ER membrane; GET pathway; SNAREs; TA proteins; root hairs