Genome-wide identification and expression analysis of the trihelix gene family in melon

The trihelix transcription factor is involved in the regulation of plant growth and development, as well as in responses to various abiotic stresses. In this study, a comprehensive analysis of the trihelix family genes in Cucumis melo was conducted, identifying a total of 28 genes in the genome. These genes were further categorized into five subfamilies: GT-1, GT-2, SH4, GTγ, and SIP1. This study involved a systematic analysis of the gene structure, chromosomal distribution, tandem and segmental duplication events, conserved motifs, phylogenetic relationships, and cis-acting elements of these trihelix genes. The syntenic analysis highlighted strong collinearity between trihelix family genes in Cucumis melo and Arabidopsis thaliana , followed by Oryza sativa , while showing limited collinearity with those in Brachypodium distachyon. Cis-element analysis revealed 73 different types of cis-acting elements that are involved in stress tolerance, hormone signaling, growth and development, and light response in plants. The expression patterns of melon trihelix family genes in different tissues and developmental stages were analyzed using publicly available datasets. The greater expression of the genes CmTH08 , and CmTH10 in fruit tissues indicates their potential roles in fruit development. Based on the identification of cis-acting elements and phylogenetic analysis, the possible roles of the genes CmTH02, CmTH16, CmTH20, CmTH21, CmTH24, CmTH26, and CmTH28 in abiotic stress tolerance were revealed. These findings contribute to enhancing the overall understanding of the melon trihelix family. Furthermore, this research identified potential candidate genes to facilitate genetic enhancement to sustain stress resistance in melons.