biostudies-literatureUnknown13(12)Yan XHomeodomain-leucine zipper (HD-ZIP) transcription factors are one of the plant-specific gene families involved in plant growth and response to adverse environmental conditions. However, little information is available on the HD-ZIP gene family in watermelon. In this study, forty <i>ClHDZs</i> were systemically identified in the watermelon genome, which were subsequently divided into four distinctive subfamilies (I-IV) based on the phylogenetic topology. HD-ZIP members in the same subfamily generally shared similar gene structures and conserved motifs. Syntenic analyses revealed that segmental duplications mainly contributed to the expansion of the watermelon HD-ZIP family, especially in subfamilies I and IV. HD-ZIP III was considered the most conserved subfamily during the evolutionary hisGenes2242https://www.ebi.ac.uk/biostudies/studies/S-EPMC9777774biostudies-literatureThe HD-ZIP Gene Family in Watermelon: Genome-Wide Identification and Expression Analysis under Abiotic Stresses.PMC9777774Pan XLi XLuan FYang JLi JZhang XWei CSi FChen XYan XYue ZfalseThe HD-ZIP Gene Family in Watermelon: Genome-Wide Identification and Expression Analysis under Abiotic Stresses.Homeodomain-leucine zipper (HD-ZIP) transcription factors are one of the plant-specific gene families involved in plant growth and response to adverse environmental conditions. However, little information is available on the HD-ZIP gene family in watermelon. In this study, forty <i>ClHDZs</i> were systemically identified in the watermelon genome, which were subsequently divided into four distinctive subfamilies (I-IV) based on the phylogenetic topology. HD-ZIP members in the same subfamily generally shared similar gene structures and conserved motifs. Syntenic analyses revealed that segmental duplications mainly contributed to the expansion of the watermelon HD-ZIP family, especially in subfamilies I and IV. HD-ZIP III was considered the most conserved subfamily during the evolutionary his2022-01-01T00:00:00Z2022 Nov2025-04-18T16:34:00.736Z2025-04-07T03:49:59.151ZS-EPMC97777743655350910.3390/genes13122242