Abstract: 【Aim】 The objective of this study is to clone the cDNA sequence of transcription factor AP-1 gene (AccAP-1) from Apis cerana cerana and to explore its expression profiles in A. cerana cerana at different developmental stages, in different tissues and under different abiotic stress, so as to provide fundamental evidence for the future study of the physiological function of AccAP-1. 【Methods】 The full-length cDNA sequence of AP-1 gene was cloned from the entire tissues of A. cerana cerana by RT-PCR. Physiochemical properties and structure characteristics of the deduced amino acid sequence were analyzed by multiple bioinformatics methods. Phylogenetic tree between AP-1 from A. cerana cerana and its homologous AP-1 proteins from other hymenopteran insects was constructed using neighbor-joining method of MEGA5.2. The expression levels of AP-1 gene in A. cerana cerana at different developmental stages (1-6 d old larva, prepupa, white-eyed pupa, pink-eyed pupa, dark-eyed pupa, 1 d-old adult worker, and 15 d-old adult worker), in different tissues (head, muscle, epidermis, midgut, rectum and venom gland) of 15 d-old adult workers, and in 15 d-old adult workers under stress of extreme temperatures (4, 16 and 44℃) and fed with sucrose solutions containing pesticide (0.01 mL/L paraquat) and heavy metal (1 mg/mL CdC_l2), respectively, were detected by real-time PCR. 【Results】 We obtained the full-length open reading frame (ORF) of AccAP-1 (GenBank accession no.: MF994311) from A. cerana cerana, which is 813 bp in length, encoding 270 amino acids with an estimated molecular weight of 30.24 kD and a predicted theoretical isoelectric point (pI) of 8.31. Conserved domain analysis indicated that AccAP-1 contains two highly conserved structures, i.e., Jun superfamily (AA 7-137) and bZIP_Jun (AA 195-255). The results of homologous sequence alignment and phylogenetic tree analysis indicated that A. cerana cerana was most closely related to Apis mellifera. The results of real-time PCR indicated that the expression levels of AccAP-1 at different developmental stages were significantly different (P<0.05) and the highest in 1 d-old larva and 15 d-old adult. AccAP-1 transcripts were expressed in all tissues tested, and the expression level was higher in muscles than in other tissues (P<0.05). The expression levels of AccAP-1 under different abiotic stress indicated that the low temperature 4℃ upregulated its expression (P<0.05), while the treatment at 16℃ for 0.5-2 h upregulated its expression (P<0.05), but extended treatment time at 16℃ (over 2 h) downregulated its expression. The expression level of AccAP-1 at 44℃ for 15 min was downregulated significantly (P<0.05), while those at 44℃ for the other treatment time had no significant difference (P>0.05). The expression of AccAP-1 was downregulated when the workers were fed with the sucrose solution containing paraquat (P<0.05); the expression of AccAP-1, however, was induced by CdCl₂ (P<0.05). 【Conclusion】 The results suggest that AccAP-1 might play an important role in the response to abiotic stress in A. cerana cerana.

Key words: Apis cerana cerana; transcript factor AP-1, gene cloning, gene function, stress response