Genome-wide analysis of the GPAT gene family in wheat and the potential roles of TaGPAT58 and its homologs in male reproductive development

The glycerol-3-phosphate acyltransferase (GPAT) gene family plays a critical role in the biosynthesis of lipids in plants. However, the <i>GPAT</i> gene family has not yet been systematically analyzed in wheat, and in particular, the relationship between the <i>GPAT</i> genes and male fertility in wheat (<i>Triticum aestivum</i> L.) remains unclear. In this study, a total of 64 <i>TaGPAT</i> genes were identified at the whole-genome level and classified into three clades. The genes within each clade exhibited conserved motif distributions and gene structures, whereas clear differences were observed among the different clades. A synteny analysis indicated that segmental duplication was the major driving force for the expansion of the <i>TaGPAT</i> gene family. An analysis of the expression pattern showed that the <i>TaGPAT</i> genes showed distinct expression patterns among different tissues and reproductive stages, with some genes preferentially expressed in roots, grains, or spikes, and specific <i>TaGPAT</i> genes reaching peak expression at key meiotic stages. In the temperature-sensitive male-sterile wheat line YS3038, <i>TaGPAT58</i> was specifically highly expressed at the trinucleate pollen stage under fertile conditions, and the encoded protein was localized to the endoplasmic reticulum. Virus-induced gene silencing targeted to <i>TaGPAT58</i> resulted in a reduction in the number of pollen, abnormal pollen morphology, and a significant decrease in the seed-setting rate. Collectively, this study provides a comprehensive characterization of the <i>TaGPAT</i> gene family in wheat and evidence that <i>TaGPAT58</i> and its two homoeologous genes are involved in male reproductive development, thereby offering important insights into the molecular mechanisms of male sterility and the exploitation of heterosis in wheat.