title: The translation elongation factor eEF-1Bβ1 is involved in cell wall biosynthesis and plant development in Arabidopsis thaliana.
abstract: The eukaryotic translation elongation factor eEF-1Bβ1 (EF1Bβ) is a guanine nucleotide exchange factor that plays an important role in translation elongation. In this study, we show that the EF1Bβ protein is localized in the plasma membrane and cytoplasm, and that the transcripts should be expressed in most tissue types in seedlings. Sectioning of the inflorescence stem revealed that EF1Bβ predominantly localizes to the xylem vessels and in the interfascicular cambium. EF1Bβ gene silencing in efβ caused a dwarf phenotype with 38% and 20% reduction in total lignin and crystalline cellulose, respectively. This loss-of-function mutant also had a lower S/G lignin monomer ratio relative to wild type plants, but no changes were detected in a gain-of-function mutant transformed with the EF1Bβ gene. Histochemical analysis showed a reduced vascular apparatus, including smaller xylem vessels in the inflorescence stem of the loss-of-function mutant. Over-expression of EF1Bβ in an eli1 mutant background restored a WT phenotype and abolished ectopic lignin deposition as well as cell expansion defects in the mutant. Taken together, these data strongly suggest a role for EF1Bβ in plant development and cell wall formation in Arabidopsis.
authors.affiliation: Agriculture and Agri-Food Canada, London, Ontario, Canada.
authors.forename: Zakir
authors.initials: Z
authors.lastname: Hossain
authors.forename: Lisa
authors.initials: L
authors.lastname: Amyot
authors.forename: Brian
authors.initials: B
authors.lastname: McGarvey
authors.forename: Margaret
authors.initials: M
authors.lastname: Gruber
authors.forename: Jinwook
authors.initials: J
authors.lastname: Jung
authors.forename: Abdelali
authors.initials: A
authors.lastname: Hannoufa
mesh_terms: D017360:Arabidopsis / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism; D029681:Arabidopsis Proteins / Q000235:genetics* / Q000378:metabolism; D002462:Cell Membrane / Q000378:metabolism; D002473:Cell Wall / Q000235:genetics* / Q000378:metabolism; D002482:Cellulose / Q000378:metabolism; D035264:Flowers / Q000235:genetics / Q000254:growth & development / Q000378:metabolism; D018507:Gene Expression Regulation, Developmental; D018506:Gene Expression Regulation, Plant; D006651:Histocytochemistry; D056626:Inflorescence / Q000235:genetics / Q000254:growth & development / Q000378:metabolism; D008031:Lignin / Q000378:metabolism; D008164:Luminescent Proteins / Q000235:genetics / Q000378:metabolism; D018613:Microscopy, Confocal; D009154:Mutation; D020648:Peptide Elongation Factor 1 / Q000235:genetics* / Q000378:metabolism; D010445:Peptide Elongation Factors / Q000235:genetics* / Q000378:metabolism; D030821:Plants, Genetically Modified; D020133:Reverse Transcriptase Polymerase Chain Reaction; D036226:Seedlings / Q000235:genetics / Q000254:growth & development / Q000378:metabolism; D052584:Xylem / Q000235:genetics / Q000254:growth & development / Q000378:metabolism
chemical_list: D029681:Arabidopsis Proteins; D008164:Luminescent Proteins; D020648:Peptide Elongation Factor 1; D010445:Peptide Elongation Factors; C572613:eEF-1Bbeta1 protein, Arabidopsis; D002482:Cellulose; D008031:Lignin