Supplementary Material for: Sexual Dimorphic Expression of Dmrt1 in Adult Japanese gecko (Gekko japonicus)

Introduction：The Dmrt1 gene is essential for sex determination and gonadal development in various animals. In Gekko japonicus, its expression correlates with the breeding cycle and sexual characteristics. This article investigates the seasonal variations and sexual dimorphism of Dmrt1, highlighting its regulatory mechanisms and physiological associations. Methods：Total RNA was extracted from adult G. japonicus testes, and the full-length Dmrt1 transcript was obtained through 3' and 5' RACE. Bioinformatics predicted its properties, and phylogenetic analysis was conducted using raxmlGUI 2.0. Real-time PCR evaluated gjDmrt1 expression in male and female tissues and gonads. Results：The gjDmrt1-encoded protein is a hydrophilic nuclear protein with a conserved 54-amino acid DM domain, exhibiting high conservation among vertebrates. RT-qPCR shows significant differential expression in male tissues, gender dimorphism favoring males, and expression peaks in April with notable periodic fluctuations. Conclusion: This study offers critical insights into the characterization of the Dmrt1 gene in G. japonicus. The findings underscore its significant role in seasonal reproductive regulation and provide essential information for further investigation into the interactions between Dmrt1 and other candidate genes associated with sex determination, as well as its regulatory mechanisms across varying environmental conditions.