Abstract
XTH (Xyloglucan endotransglucosylase/hydrolysase) is a class of enzymes that can mediate endotransglucosylation and/or hydrolysis of xyloglucan molecules. In Arabidopsis thaliana, 33 genes encoding XTH proteins have been identified. Individual members of this gene family were shown to exhibit distinct expression profiles, temporally and spatially. Each XTH member is considered to play the role individually in plant morphogenesis. To gain insight into roles of individual members of the gene family, we have isolated and analyzed phenotypes of homogeneous T-DNA insertion lines, which cover 24 XTH genes. We found that the xth12 mutant has defect in root growth and the xth27 mutant has lesions in leaves. On the other hand, no macroscopic phenotype was observed in other xth mutants. The result indicates that most of XTH genes are redundant functionally, but some XTH genes play important roles individually in specific aspects during the plant growth and development.
