Mutant Name: mur3

Gene Name MUR3
Protein Name Xyloglucan-galactosyl transferase
Mutagen EMS
Category forward genetics
Organism Arabidopsis thaliana
Ecotype Col
Donor
General Description 1.L-fucose content is reduced to 50%of the wild type.
2.Plants were phenotypically normal and exhibited tensile strength in their inflorescence stems comparable to that of wild-type plants.
Organ Specificity L-fucose content in aerial organs reduced to 50% of the wild type. The change in XyG structure affected all major plant organs.
Impact on Wall mur3 mutation affects the monosaccharide composition of XyG. Plant exhibited tensile strength in their inflorescence stems
Impact on Sugar Composition 1.Mutants have 50% reduction in cell wall fucose content.
2.mur3 defect results in a failure of attachment of the Gal residue on the third xylosyl unit within the XXXG core structure. This failure severely alters the XyG structure in two ways.
First, the L-Fuc-(1,2)-D-Gal- side group, which is considered important for XyG binding to cellulose, is completely absent.
Second, galactosylation at the second xylose residue is enhanced.
Reference 1. Reiter WD, Chapple CCS, Somerville CR (1997) Mutant of Arabidopsis thaliana with altered cell wall polysaccharide composition. Plant J 12: 335-345

2. Madson M, Dunand C, Li X, Verma R, Vanzin GF, Caplan J, Shoue DA, Carpita NC, Reiter WD.(2003) The MUR3 gene of Arabidopsis encodes a xyloglucan galactosyltransferase that is evolutionarily related to animal exostosins. Plant Cell. Jul;15(7):1662-70.