Abstract:The aims of this study were to examine the structural features of the amino acid sequence encoded by genes and to analyze the expression patterns of these genes during gonadal development, to understand the role of hypothalamic neuropeptide kisspeptin in reproductive regulation of Amur sturgeon (). We used reverse transcription PCR and rapid-amplification of cDNA ends (RACE) technology to obtain the full-length cDNA of kiss1 gene of gene was 518 bp, encoding 149 amino acids. Among them, the α-helix and irregular distortion in Kiss1 and Kiss2 are regarded as the main components in the secondary structure, both containing signal peptide, transmembrane structure, and unstable hydrophilic protein secreted outside the cell. Amino acid sequence alignment and phylogenetic tree analysis showed that had highly conserved regions, which had the highest consistency (and the closest relationship) with the Acipenser dabryanus). The results of real-time PCR showed that the expression of kiss1 had the highest expression in the gonads, while expression was the highest in the brain. In the early gonadal development of was lower at 0-49 d after hatching, while the expression of was higher, reaching the maximum at 21 d after hatching. With the development of gonads in gradually increased and reached the highest at 139 d, followed by a decline. In contrast, the expression level of reached the maximum at 184 days after hatching. In summary, the kisspeptin gene plays an important role in the early gonadal development of , with differing regulatory functions. This study lays a theoretical foundation for further elucidating the physiological functions and molecular regulation mechanisms of genes.