Genome-wide analysis of the TCP transcription factor family in mung bean and its dynamic regulatory network under salt stress

The TCP gene family encodes plant-specific transcription factors that regulate plant growth, development, and stress responses. Although this gene family has been widely studied in various species, its function in mung bean (<i>Vigna radiata</i>) remains unclear. In this study, we identified 26 VrTCP genes, which were classified into two groups: Class I (PCF subfamily) and Class II (CYC/TB1 and CIN subfamilies). These family members likely function in the nucleus. VrTCP genes are unevenly distributed across chromosomes and are associated with gene duplication events. Their cis-regulatory elements are involved in plant growth, hormone signaling, and stress responses. Co-expression network analysis further supports these findings, identifying 1,304 genes co-expressed with VrTCPs, among which <i>VrTCP19</i>, <i>VrTCP10</i>, <i>VrTCP16</i>, and <i>VrTCP20</i> act as hub genes regulating hormone signaling and the MAPK pathway. Overall, VrTCP genes play a key role in salt stress responses, providing molecular insights that may facilitate the development of salt-tolerant mung bean varieties through molecular breeding. These findings also offer a foundation for future functional studies aimed at improving crop resilience under abiotic stress conditions.