In:
Scientific Reports, Springer Science and Business Media LLC, Vol. 7, No. 1 ( 2017-03-30)
Abstract:
Extensins are plant cell wall glycoproteins that act as scaffolds for the deposition of the main wall carbohydrate polymers, which are interlocked into the supramolecular wall structure through intra- and inter-molecular iso-di-tyrosine crosslinks within the extensin backbone. In the conserved canonical extensin repeat, Ser-Hyp 4 , serine and the consecutive C4-hydroxyprolines (Hyps) are substituted with an α-galactose and 1–5 β- or α-linked arabinofuranoses (Ara f s), respectively. These modifications are required for correct extended structure and function of the extensin network. Here, we identified a single Arabidopsis thaliana gene, At3g57630, in clade E of the inverting Glycosyltransferase family GT47 as a candidate for the transfer of Ara f to Hyp-arabinofuranotriose (Hyp-β1,4Ara f -β1,2Ara f -β1,2Ara f ) side chains in an α-linkage, to yield Hyp-Ara f 4 which is exclusively found in extensins. T-DNA knock-out mutants of At3g57630 showed a truncated root hair phenotype, as seen for mutants of all hitherto characterized extensin glycosylation enzymes; both root hair and glycan phenotypes were restored upon reintroduction of At3g57630. At3g57630 was named Extensin Arabinose Deficient transferase, ExAD, accordingly. The occurrence of ExAD orthologs within the Viridiplantae along with its’ product, Hyp-Ara f 4 , point to ExAD being an evolutionary hallmark of terrestrial plants and charophyte green algae.
Type of Medium:
Online Resource
ISSN:
2045-2322
Language:
English
Publisher:
Springer Science and Business Media LLC
Publication Date:
2017
detail.hit.zdb_id:
2615211-3
