Abstract: 【Aim】 To clarify the molecular characteristics and tissue expression properties of the biogenic amine receptor genes in Mythimna separata based on the adult brain transcriptome data of M. separata, so as to provide the basis for the functional research of the biogenic amine receptor genes of M. separata. 【Methods】 The biogenic amine receptor gene sequences were screened from the brain transcriptome database of adult M. separata. Gene mapping of the selected biogenic amine receptor genes was analyzed by mapping cDNA with the M. separata genome database. The phylogenetic analysis of the identified biogenic amine receptors was performed by using maximum likelihood method. The qRT-PCR was used to detect the expression levels of the identified biogenic amine receptor genes in the brain, antenna, labipalp, wing, leg, thorax and abdomen of female and male adults of M. separata.【Results】 A total of 17 biogenic amine receptor genes were identified from the transcriptome database of adult M. separata brain, including five dopamine receptor genes, five 5-hydroxytryptamine receptor genes, five octopamine receptor genes and two tyramine receptor genes. The 17 biogenic amine receptor genes were distributed on eight chromosomes, 7 of them were co-located on the chromosome 22. The identified biogenic amine receptors of M. separata had high homology with the biogenic amine receptors of Spodoptera litura, Bombyx mori and Manduca sexta. The dopamine receptor genes were highly expressed in the brain and antenna of female and male adults of M. separata, and the expression levels of MsepDop2, MsepDop3-1, MsepDop3-2 and MsepDopEcR were significantly higher in the female adult brain than those in the male adult brain. The octopamine receptor genes MsepOA1 and MsepOA2B2 were highly expressed in the thorax, and their expression levels in the thorax of female adults were significantly higher than those in the thorax of male adults. The expression levels of MsepOA3 and MsepOA2B1-3 were also higher in the olfactory tissues antenna and labipalp, with gender differences. The expression levels of tyramine receptor genes were high in the brain and antenna, and the expression level of MsepTA2 in the abdomen of female adults was significantly higher than that in the abdomen of male adults. The expression levels of Msep5-HT1 genes in the brain were significantly higher than those in the other tissues. The Msep5-HT2 genes had high expression levels in the brain, antenna, and labipalp.【Conclusion】 In this study, we obtained 17 biogenic amine receptor genes of M. separata, and clarified their expression profiles in different tissues of female and male adults of M. separata. Gender differences in the expression of some biogenic amine receptor genes in olfactory and reproductive tissues were revealed. This research provides a basis for further exploration on the physiological function of biogenic amine receptors in M. separata.

Key words: Mythimna separata, biogenic amine receptor, transcriptome, phylogeny, expression profile