Abstract: 【Aim】 In order to explore the relationship between sex peptide (SP) and post-mating response (PMR), the sex peptide receptor (SPR) gene from Helicoverpa assulta (Guenée) was cloned and its expression patterns were analyzed. 【Methods】 The full-length cDNA sequence of SPR gene was cloned from sex pheromone glands of H. assulta by RT-PCR method. The expression patterns of SPR gene were analyzed by using qRT-PCR. 【Results】 The full-length cDNA sequence of SPR gene from H. assulta is 2 048 bp in size and named as HassSPR (GenBank accession number: AFH53182.1). The open reading frame of HassSPR is 1 275 bp that encodes 424 amino acid residues with 7 putative transmembrane domains. The predicted molecular weight and isoelectric point of HassSPR are 48.6 kDa and 9.25, respectively. The alignment analysis indicated that HassSPR shared 98.35% and over 84% amino acid sequence identities with SPR proteins from its close relative species H. armigera and other moths, respectively, and shared high identities (>64%) with the corresponding SPR proteins from other insects. The tissue expression profiles revealed that HassSPR could be detected in all tested tissues of 1 day-old female adults of H. assulta, and had the highest expression level in brain. The temporal expression profiles showed that the HassSPR was expressed in female pheromone gland from 1 d before emergence to 6 d after emergence and reached the peak at 3 d after emergence. After mating, the expression level of HassSPR in female brain and pheromone gland significantly increased, while that in bursa copulatrix and ovary significantly decreased. 【Conclusion】 The sex peptide receptor gene HassSPR was cloned from sex pheromone glands of H. assulta. The expression level of HassSPR is associated with the reproductive physiology and reproductive behavior of female adults of this moth.

Key words:  Helicoverpa assulta, sex peptide, sex peptide receptor, sex pheromone gland, gene expression pattern, mating