Abstract
During the growth process, wheat (Triticum aestivum L.) is frequently subjected to abiotic stress. However, the mechanisms of abiotic stress in wheat are not yet well understood. In other crops, 4-coumarate-CoA ligases (4CLs) have been found to be involved in abiotic stress responses, but a systematic analysis of the response of 4CLs to abiotic stress in wheat has not yet been conducted. Through a comprehensive genome-wide analysis, we identified 110 putative 4CL genes in wheat. These genes were phylogenetically divided into distinct groups, with the authentic 4CLs forming a separate branch and 4CL-like genes being further categorized into six subgroups. Each clade exhibited conserved gene structures and motif compositions. Promoter analysis identified a variety of stress-responsive cis-regulatory elements within Ta4CL genes, indicating their potential involvement in stress regulation mechanisms. Expression profiling under drought and salt stress conditions identified specific 4CL genes linked to stress tolerance. Notably, Ta4CL91, a member of the 4CL clade, showed strong dual responsiveness to both drought and salt stresses. Using virus-induced gene silencing (VIGS), we suppressed Ta4CL91 expression and observed that the Ta4CL91-silenced plants became more sensitive to drought and salt stresses, highlighting Ta4CL91's critical role in stress adaptation in wheat. This comprehensive study not only expands our understanding of the 4CL gene family in wheat but also highlights the critical involvement of specific 4CL members, such as Ta4CL91, in mediating this plant's resistance to abiotic stresses.