title: Differences in glycosyltransferase family 61 accompany variation in seed coat mucilage composition in Plantago spp.
abstract: Xylans are the most abundant non-cellulosic polysaccharide found in plant cell walls. A diverse range of xylan structures influence tissue function during growth and development. Despite the abundance of xylans in nature, details of the genes and biochemical pathways controlling their biosynthesis are lacking. In this study we have utilized natural variation within the Plantago genus to examine variation in heteroxylan composition and structure in seed coat mucilage. Compositional assays were combined with analysis of the glycosyltransferase family 61 (GT61) family during seed coat development, with the aim of identifying GT61 sequences participating in xylan backbone substitution. The results reveal natural variation in heteroxylan content and structure, particularly in P. ovata and P. cunninghamii, species which show a similar amount of heteroxylan but different backbone substitution profiles. Analysis of the GT61 family identified specific sequences co-expressed with IRREGULAR XYLEM 10 genes, which encode putative xylan synthases, revealing a close temporal association between xylan synthesis and substitution. Moreover, in P. ovata, several abundant GT61 sequences appear to lack orthologues in P. cunninghamii. Our results indicate that natural variation in Plantago species can be exploited to reveal novel details of seed coat development and polysaccharide biosynthetic pathways.
authors.affiliation: Australian Research Council Centre of Excellence in Plant Cell Walls, School of Agriculture, Food and Wine, University of Adelaide, Waite Campus, Urrbrae, SA 5064, Australia.
authors.forename: Jana L
authors.initials: JL
authors.lastname: Phan
authors.affiliation: Australian Research Council Centre of Excellence in Plant Cell Walls, School of Agriculture, Food and Wine, University of Adelaide, Waite Campus, Urrbrae, SA 5064, Australia.
authors.forename: Matthew R
authors.initials: MR
authors.lastname: Tucker
authors.affiliation: Australian Research Council Centre of Excellence in Plant Cell Walls, School of Agriculture, Food and Wine, University of Adelaide, Waite Campus, Urrbrae, SA 5064, Australia.
authors.forename: Shi Fang
authors.initials: SF
authors.lastname: Khor
authors.affiliation: Australian Research Council Centre of Excellence in Plant Cell Walls, School of Agriculture, Food and Wine, University of Adelaide, Waite Campus, Urrbrae, SA 5064, Australia.
authors.forename: Neil
authors.initials: N
authors.lastname: Shirley
authors.affiliation: Australian Research Council Centre of Excellence in Plant Cell Walls, School of Agriculture, Food and Wine, University of Adelaide, Waite Campus, Urrbrae, SA 5064, Australia.
authors.forename: Jelle
authors.initials: J
authors.lastname: Lahnstein
authors.affiliation: Australian Research Council Centre of Excellence in Plant Cell Walls, School of Botany, University of Melbourne, Parkville Campus, VIC 3010, Australia.
authors.forename: Cherie
authors.initials: C
authors.lastname: Beahan
authors.affiliation: Australian Research Council Centre of Excellence in Plant Cell Walls, School of Botany, University of Melbourne, Parkville Campus, VIC 3010, Australia.
authors.forename: Antony
authors.initials: A
authors.lastname: Bacic
authors.affiliation: Australian Research Council Centre of Excellence in Plant Cell Walls, School of Agriculture, Food and Wine, University of Adelaide, Waite Campus, Urrbrae, SA 5064, Australia rachel.burton@adelaide.edu.au.
authors.forename: Rachel A
authors.initials: RA
authors.lastname: Burton
mesh_terms: D016695:Glycosyltransferases / Q000235:genetics / Q000378:metabolism*; D008853:Microscopy; D008855:Microscopy, Electron, Scanning; D010802:Phylogeny; D062087:Plant Mucilage / Q000032:analysis / Q000378:metabolism*; D010943:Plantago / Q000201:enzymology / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D016133:Polymerase Chain Reaction; D012639:Seeds / Q000737:chemistry / Q000201:enzymology / Q000254:growth & development / Q000502:physiology*
chemical_list: D062087:Plant Mucilage; D016695:Glycosyltransferases
keywords: 
  Plantago
  ; Glycosyltransferase family 61; heteroxylan; plant cell walls; polysaccharide biosynthesis; seed mucilage.