Abstract:  In order to investigate the effects of injecting Dnmt3 siRNA on Dnmt3 activity, Dnmt3 mRNA expression level, methylation status of the dynactin p62 gene and the morphological characters in female Apis mellifera ligustica, 50 ng Ringer, uth siRNA and Dnmt3 siRNA were injected into 3 d old female larvae of A. mellifera ligustica reared in an incubator, respectively. Dnmt3 activity, Dnmt3 mRNA expression level, and dynactin p62 methylation level in larval head and the morphological characters including body weight, body length, forewing length, forewing width, proboscis length and 3rd tergum length of newly emerged female adults were examined. The results showed that Dnmt 3 activity, the Dnmt3 expression level and the methylation level of dynactin p62 in larval head were significantly inhibited after the larvae were injected with Dnmt3 siRNA, while the body weight, body length and 3rd tergum length of newly emerged female adults increased, indicating that the changes of Dnmt3 have an effect on female larvae of A. mellifera ligustica during their development.

Key words: Apis mellifera ligustica, queen, worker, siRNA, Dnmt3, dynactin p62