RRC ID 36929
著者 Basu D, Tian L, Wang W, Bobbs S, Herock H, Travers A, Showalter AM.
タイトル A small multigene hydroxyproline-O-galactosyltransferase family functions in arabinogalactan-protein glycosylation, growth and development in Arabidopsis.
ジャーナル BMC Plant Biol
Abstract BACKGROUND:Arabinogalactan-proteins (AGPs) are ubiquitous components of cell walls throughout the plant kingdom and are extensively post translationally modified by conversion of proline to hydroxyproline (Hyp) and by addition of arabinogalactan polysaccharides (AG) to Hyp residues. AGPs are implicated to function in various aspects of plant growth and development, but the functional contributions of AGP glycans remain to be elucidated. Hyp glycosylation is initiated by the action of a set of Hyp-O-galactosyltransferase (Hyp-O-GALT) enzymes that remain to be fully characterized.
RESULTS:Three members of the GT31 family (GALT3-At3g06440, GALT4-At1g27120, and GALT6-At5g62620) were identified as Hyp-O-GALT genes by heterologous expression in tobacco leaf epidermal cells and examined along with two previously characterized Hyp-O-GALT genes, GALT2 and GALT5. Transcript profiling by real-time PCR of these five Hyp-O-GALTs revealed overlapping but distinct expression patterns. Transiently expressed GALT3, GALT4 and GALT6 fluorescent protein fusions were localized within Golgi vesicles. Biochemical analysis of knock-out mutants for the five Hyp-O-GALT genes revealed significant reductions in both AGP-specific Hyp-O-GALT activity and β-Gal-Yariv precipitable AGPs. Further phenotypic analysis of these mutants demonstrated reduced root hair growth, reduced seed coat mucilage, reduced seed set, and accelerated leaf senescence. The mutants also displayed several conditional phenotypes, including impaired root growth, and defective anisotropic growth of root tips under salt stress, as well as less sensitivity to the growth inhibitory effects of β-Gal-Yariv reagent in roots and pollen tubes.
CONCLUSIONS:This study provides evidence that all five Hyp-O-GALT genes encode enzymes that catalyze the initial steps of AGP galactosylation and that AGP glycans play essential roles in both vegetative and reproductive plant growth.
巻・号 15
ページ 295
公開日 2015-12-21
DOI 10.1186/s12870-015-0670-7
PII 10.1186/s12870-015-0670-7
PMID 26690932
PMC PMC4687291
MeSH Arabidopsis / genetics* Arabidopsis / growth & development Arabidopsis / metabolism Arabidopsis Proteins / genetics* Arabidopsis Proteins / metabolism Galactosyltransferases / genetics* Galactosyltransferases / metabolism Gene Expression Regulation, Developmental Gene Expression Regulation, Plant* Glycosylation Hydroxyproline / metabolism Mucoproteins / genetics* Mucoproteins / metabolism Multigene Family Plant Proteins / genetics Plant Proteins / metabolism Plants, Genetically Modified / genetics Plants, Genetically Modified / metabolism Tobacco / genetics Tobacco / metabolism
IF 3.497
引用数 18
WOS 分野 PLANT SCIENCES
リソース情報
シロイヌナズナ / 植物培養細胞・遺伝子 pda01627 pda09678 pda11283