Genome-Wide Identification and Expression Analysis of the WSD Gene Family in Wheat

Wax synthase/diacylglycerol acyltransferases (WS/DGATs), often referred to as WSD proteins, represent a class of key enzymes that catalyze the biosynthesis of wax esters in plants and other organisms. However, the WSD gene family in wheat (Triticum aestivum) has not been systematically characterized.

A comprehensive genome-wide identification and bioinformatic characterization of the WSD gene family were conducted in wheat, followed by an analysis of chromosomal locations, gene structures, conserved motifs, phylogenetic relationships, expression profiles, and cis-element predictions.

In this study, a total of 43 TaWSDs were identified through genome-wide analysis in wheat. All identified TaWSD members exhibit highly conserved structural features and contain the core catalytic motif HHXXXDG. Phylogenetic analysis of WSD proteins from 63 species revealed that WSDs in Triticeae, including wheat, were mainly clustered into four distinct clades. Furthermore, sequence divergence among TaWSDs from different clades was primarily localized to the N-terminal region. Notably, expression profile analysis demonstrated that TaWSD genes display organ-specific expression patterns in wheat. Among them, 12 TaWSDs showed the highest expression levels in the leaf lamina joint, implying their potential involvement in the regulation of leaf angle formation. Additionally, 27 transcription factors were computationally predicted as putative regulators of TaWSDs, although their exact roles require further experimental confirmation.

Our findings provide novel insights into the biological functions of the wheat WSD gene family and offer new perspectives for elucidating their molecular mechanisms underlying plant architecture regulation.