关键词: 中华蜜蜂, 雄蜂, 气味受体基因, AcOr10, 性成熟, 基因表达

Abstract: 【Aim】 Olfactory receptor Or10 is one of the important receptor proteins for the perception of pheromone in the honeybee, Apis cerana cerana. The aim of this study is to clone the sequence of Or10 gene, and to analyze the expression levels of Or10 in drone antennae and brains across various physiological status, so as to provide the theoretical basis for further studies on the biological function of this gene. 【Methods】 The drone antennae of A. cerana cerana were collected, from which the total RNA was extracted to clone the sequence of Or10. The relative expression levels of Or10 in antennae and brains of drones, which were sexually immature at hive entrance, sexually mature at hive entrance, sexually immature at frames in hive and sexually mature at frames in hive, were detected using quantitative real-time PCR (qPCR). 【Results】 The cDNA sequence of Or10 gene (named as AcOr10) (GenBank accession no.: MF693365) of A. cerana cerana was obtained, with the length of 914 bp and a coding region of 738 bp, encoding 246 amino acids. The encoded protein has the molecular weight of 28.163 kD and isoelectric point of 5.50. The phylogenetic tree showed that AcOr10 clustered with Or10 of A. mellifera and Or4-like of A. florea. The relative expression levels of AcOr10 in antennae of sexually immature drones at hive entrance and sexually mature ones at frames in hive were significantly higher than those of sexually immature drones at hive entrance and sexually immature drones at frames in hive (P<0.05). However there was no significant difference in the relative expression level of AcOr10 in antennae between sexually mature drones at hive entrance and mature ones at frames in hive (P>0.05). There was also no significant difference in the relative expression level of AcOr10 in antennae between sexually immature drones at hive entrance and immature ones at frames in hive (P>0.05). The relative expression level of AcOr10 in brains of sexually mature drones at hive entrance was significantly higher than those of drones sexually immature at hive entrance, sexually immature at frames in hive and sexually mature at frames in hive (P<0.05), while there was no significant difference among the latter three groups (P>0.05). The relative expression levels of AcOr10 in antennae of drones sexually immature at hive entrance, sexually immature at frames in hive and sexually mature at frames in hive were all significantly higher than those in brains of drones with the same physiological status (P<0.05), but there was no significant difference in the expression level of AcOr10 between antennae and brains of drones sexually mature at hive entrance (P>0.05). 【Conclusion】 It is inferred that AcOr10 may be related with sexual maturity of A. cerana cerana drones, and flight activities have little influence on the expression of AcOr10 in antennae but cause the changes of brains, thereby affecting the mating behaviour of drones.

Key words: Apis cerana cerana, drones, olfactory receptor gene, AcOr10, sexual maturity, gene expression