Genome-wide identification and expression analysis of YTH domain-containing RNA-binding protein family in maize reveals their potential role under abiotic stresses

Post-transcriptional control of gene expression is one of the strategies in plants to regulate growth, development, and stress adaptation. YT521-B homology (YTH) domain-containing RNA-binding proteins are essential for this post-transcriptional control through influencing the fate of RNA molecules containing N6-methyladenosine (m⁶A). Here, we conducted a genome-wide identification and characterization analysis of the YTH gene family in maize (Zea mays L.) and found 22 ZmYTHs. Phylogenetic analysis showed that the ZmYTH could be divided into four groups, while the ZmYTH genes are distributed across ten chromosomes. Subcellular localization analysis suggests that most ZmYTH proteins often exhibit a nuclear localization consistent with their involvement in RNA metabolism. Duplication of genes, in particular segmental and whole-genome duplications, has driven the proliferation of this gene family, potentially endowing maize with greater capacity to regulate stress-responsive pathways. Further, we identified 31 cis-regulatory elements in the promoter regions of ZmYTH genes involved in development, stress, and hormonal regulation. Protein-protein interaction prediction and miRNA target prediction further elaborate their role in post-transcriptional modification. We profiled ZmYTH's expression pattern across development and stress conditions, confirming 10 genes differentially expressed under drought, salt, and heat stresses. ZmYTH1 and ZmYTH3 were consistently induced, ZmYTH7 was repressed under all three conditions, and the remaining genes showed condition-specific patterns. Overall, these findings highlight the key role of the ZmYTH family in stress adaptation and provide a basis for future studies on its molecular mechanisms.