Genome-wide characterization of WRI1(WRINKLED1) gene family as a regulators of abiotic stress response in Coix (Coix lacryma-jobi L.)

Coix (Coix lacryma-jobi L.), known as the "King of the Gramineae" for its nutritional and medicinal value, is a dual-purpose crop with both edible and therapeutic applications. WRI1 (WRINKLED1), an AP2 family transcription factor, plays a pivotal role in plant development and stress adaptation. Although WRI1 genes have been studied in several species, their functions in Coix remain largely uncharacterized. Here, we identified 20 ClWRI1 genes distributed across 10 chromosomes and classified them into three subfamilies based on phylogenetic relationships, conserved motifs, and gene structures. Expression profiling revealed that ClWRI1 genes are widely expressed, with pronounced levels in seeds. Transcriptomic and qRT-PCR analyses showed that several ClWRI1 genes respond to drought, salinity, cold, and heat stress, suggesting their involvement in abiotic stress responses. Heterologous expression of ClWRI1-18 and ClWRI1-20 in yeast conferred enhanced stress tolerance, supporting their functional relevance. Yeast two-hybrid assays further confirmed a physical interaction between ClWRI1-18 and ClWRI1-20. Collectively, these findings indicate that the WRI1 gene family contributes to stress adaptation in Coix, with ClWRI1-18 and ClWRI1-20 representing key candidates for genetic improvement.