Glycosyl transferases in family 61 mediate arabinofuranosyl transfer onto xylan in grasses.
Proc Natl Acad Sci U S A
; 109(3): 989-93, 2012 Jan 17.
Article
em En
| MEDLINE
| ID: mdl-22215597
ABSTRACT
Xylan, a hemicellulosic component of the plant cell wall, is one of the most abundant polysaccharides in nature. In contrast to dicots, xylan in grasses is extensively modified by α-(1,2)- and α-(1,3)-linked arabinofuranose. Despite the importance of grass arabinoxylan in human and animal nutrition and for bioenergy, the enzymes adding the arabinosyl substitutions are unknown. Here we demonstrate that knocking-down glycosyltransferase (GT) 61 expression in wheat endosperm strongly decreases α-(1,3)-linked arabinosyl substitution of xylan. Moreover, heterologous expression of wheat and rice GT61s in Arabidopsis leads to arabinosylation of the xylan, and therefore provides gain-of-function evidence for α-(1,3)-arabinosyltransferase activity. Thus, GT61 proteins play a key role in arabinoxylan biosynthesis and therefore in the evolutionary divergence of grass cell walls.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Arabinose
/
Xilanos
/
Glicosiltransferases
/
Poaceae
Idioma:
En
Revista:
Proc Natl Acad Sci U S A
Ano de publicação:
2012
Tipo de documento:
Article
País de afiliação:
Reino Unido