title: A galactosyltransferase acting on arabinogalactan protein glycans is essential for embryo development in Arabidopsis.
abstract: Arabinogalactan proteins (AGPs) are a complex family of cell-wall proteoglycans that are thought to play major roles in plant growth and development. Genetic approaches to studying AGP function have met limited success so far, presumably due to redundancy within the large gene families encoding AGP backbones. Here we used an alternative approach for genetic dissection of the role of AGPs in development by modifying their glycan side chains. We have identified an Arabidopsis glycosyltransferase of CAZY family GT31 (AtGALT31A) that galactosylates AGP side chains. A mutation in the AtGALT31A gene caused the arrest of embryo development at the globular stage. The presence of the transcript in the suspensor of globular-stage embryos is consistent with a role for AtGALT31A in progression of embryo development beyond the globular stage. The first observable defect in the mutant is perturbation of the formative asymmetric division of the hypophysis, indicating an essential role for AGP proteoglycans in either specification of the hypophysis or orientation of the asymmetric division plane.
authors.affiliation: Department of Plant Biology and Biotechnology, University of Copenhagen, Thorvaldsensvej 40, Copenhagen, Frederiksberg C, 1871, Denmark.
authors.forename: Naomi
authors.initials: N
authors.lastname: Geshi
authors.forename: Jorunn N
authors.initials: JN
authors.lastname: Johansen
authors.forename: Adiphol
authors.initials: A
authors.lastname: Dilokpimol
authors.forename: Aurélia
authors.initials: A
authors.lastname: Rolland
authors.forename: Katia
authors.initials: K
authors.lastname: Belcram
authors.forename: Stéphane
authors.initials: S
authors.lastname: Verger
authors.forename: Toshihisa
authors.initials: T
authors.lastname: Kotake
authors.forename: Yoichi
authors.initials: Y
authors.lastname: Tsumuraya
authors.forename: Satoshi
authors.initials: S
authors.lastname: Kaneko
authors.forename: Theodora
authors.initials: T
authors.lastname: Tryfona
authors.forename: Paul
authors.initials: P
authors.lastname: Dupree
authors.forename: Henrik V
authors.initials: HV
authors.lastname: Scheller
authors.forename: Herman
authors.initials: H
authors.lastname: Höfte
authors.forename: Gregory
authors.initials: G
authors.lastname: Mouille
mesh_terms: D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000196:embryology / Q000201:enzymology* / Q000235:genetics; D002473:Cell Wall / Q000378:metabolism; D005685:Galactans / Q000378:metabolism*; D005700:Galactosyltransferases / Q000235:genetics / Q000378:metabolism*; D018506:Gene Expression Regulation, Plant; D009088:Mucoproteins / Q000235:genetics / Q000378:metabolism*; D009154:Mutation; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism; D011994:Recombinant Proteins; D019076:Transgenes
chemical_list: D005685:Galactans; D009088:Mucoproteins; D010940:Plant Proteins; D011994:Recombinant Proteins; C006619:arabinogalactan proteins; D005700:Galactosyltransferases; C047006:N-acetyllactosaminide alpha-1,3-galactosyltransferase; C005653:arabinogalactan
keywords: Arabinogalactan proteins; Embryo development; Galactosyltransferase