These authors contributed equally.
Arabidopsis XXT5 gene encodes a putative α-1,6-xylosyltransferase that is involved in xyloglucan biosynthesis
Article first published online: 28 JUN 2008
No claim to original US government works. Journal compilation © 2008 Blackwell Publishing Ltd
The Plant Journal
Volume 56, Issue 1, pages 101–115, October 2008
How to Cite
Zabotina, O. A., Van De Ven, W. T.G., Freshour, G., Drakakaki, G., Cavalier, D., Mouille, G., Hahn, M. G., Keegstra, K. and Raikhel, N. V. (2008), Arabidopsis XXT5 gene encodes a putative α-1,6-xylosyltransferase that is involved in xyloglucan biosynthesis. The Plant Journal, 56: 101–115. doi: 10.1111/j.1365-313X.2008.03580.x
The naming of these genes has been changed recently (Cavalier et al., in press) to more clearly reflect that both genes encode xyloglucan xylosyltransferases and to better conform to the gene nomenclature standards adopted by the Arabidopsis community (Meinke and Koornneef, 1997). Thus, AtXT1 has become XXT1 and AtXT2 has become XXT2.
- Issue published online: 25 SEP 2008
- Article first published online: 28 JUN 2008
- Received 22 March 2008; revised 7 May 2008; accepted 21 May 2008; published online 29 July 2008.
Vol. 57, Issue 2, 386, Article first published online: 13 JAN 2009
- cell wall;
- root hair
The function of a putative xyloglucan xylosyltransferase from Arabidopsis thaliana (At1g74380; XXT5) was studied. The XXT5 gene is expressed in all plant tissues, with higher levels of expression in roots, stems and cauline leaves. A T-DNA insertion in the XXT5 gene generates a readily visible root hair phenotype (root hairs are shorter and form bubble-like extrusions at the tip), and also causes the alteration of the main root cellular morphology. Biochemical characterization of cell wall polysaccharides isolated from xxt5 mutant seedlings demonstrated decreased xyloglucan quantity and reduced glucan backbone substitution with xylosyl residues. Immunohistochemical analyses of xxt5 plants revealed a selective decrease in some xyloglucan epitopes, whereas the distribution patterns of epitopes characteristic for other cell wall polysaccharides remained undisturbed. Transformation of xxt5 plants with a 35S::HA-XXT5 construct resulted in complementation of the morphological, biochemical and immunological phenotypes, restoring xyloglucan content and composition to wild-type levels. These data provide evidence that XXT5 is a xyloglucan α-1,6-xylosyltransferase, and functions in the biosynthesis of xyloglucan.