A Surprising Diversity of Xyloglucan Endotransglucosylase/Hydrolase in Wheat: New in Sight to the Roles in Drought Tolerance.

Drought has become a major limiting factor for wheat productivity, and its negative impact on crop growth is anticipated to increase with climate deterioration in arid areas. Xyloglucan endoglycosylases/hydrolases (XTHs) are involved in constructing and remodeling cell wall structures and play an essential role in regulating cell wall extensibility and stress responses. However, there are no systematic studies on the wheat gene family. In this study, 71 wheat genes () were characterized and classified into three subgroups through phylogenetic analysis. Genomic replication promoted the expansion of . We found a catalytically active motif and a potential N-linked glycosylation domain in all TaXTHs. Further expression analysis revealed that many in the roots and shoots were significantly associated with drought stress. The wheat gene was transferred into Arabidopsis to verify a possible role of in stress response. The transgenic plants possessed higher seed germination rates and longer roots and exhibited improved tolerance to drought. In conclusion, bioinformatics and gene expression pattern analysis indicated that the genes played a role in regulating drought response in wheat. The expression of enhanced drought tolerance in Arabidopsis and supported the XTH genes' role in regulating drought stress response in plants.