Abstract: 【Aim】 The Italian honey bee, Apis mellifera ligustica, is an eusocial insect and the workers show age-dependent behavioral changes, and the mechanisms of the behavioral changes have been the hot research topic. In this study, we investigated the expression of 3 candidate miRNAs, i.e., ame-let-7, ame-miR-13b and ame-miR-279, in A. mellifera ligustica workers at different age, to confirm the differentially expressed miRNAs that may be involved in age-dependent behavioural changes in workers of the honeybee. 【Methods】 We tested the expression levels of the three miRNAs in the brain of A. mellifera ligustica workers at different age (4, 8, 12, 17, 22, 26 and 30 day-old) by RT-qPCR respectively, and then analyzed the differential expression among them. 【Results】 The expression level of ame-let-7 was reduced with the increasing age of the workers and tended to be stable after 17 day-old. The expression level of ame-miR13b increased with age of workers and kept stable in 26 and 30 day-old workers. The expression level of ame-miR-279 was near to the normal distribution, peaked in the 12 day-old workers and kept stable in over 17 day-old workers. However, the expression of all the 3 kinds of miRNAs showed a high degree of temporal specificity. 【Conclusion】 Our findings show that the levels of miRNAs expression are related with the age-dependent behavioral changes in honey bees, and the conclusions provide important information for exploring the action sites of miRNAs in the A. mellifera ligustica workers.

Key words: Apis mellifera ligustica, worker, caste differentiation, behavioral development, miRNA, RT-qPCR