Abstract: 【Aim】This study aims to provide theoretical and experimental bases for exploring the mechanism underlying Nosema ceranae infection regulated by nce-miR-10660.【Methods】Stem-loop RT-PCR was used to confirm the expression of previously identified nce-miR-10660 in N. ceranae and Sanger sequencing was performed to validate the nce-miR-10660 sequence. Related bioinformatic software was employed to predict and analyze the target genes of nce-miR-10660. RT-qPCR was used to detect the expression profiles of nce-miR-10660 and its target genes in the midguts of Apis mellifera ligustica workers during the infection process of N. ceranae. 【Results】Stem-loop RT-PCR and Sanger sequencing results confirmed the expression and true existence, respectively, of nce-miR-10660 in N. ceranae spores. Targeting prediction showed that nce-miR-10660 can target nine genes including RRDRP and RCDP 42, among which two and six target genes can be annotated to four pathways of KEGG database and 23 terms of GO database, respectively. RT-qPCR results indicated that the expression level of nce-miR-10660 in the midgut of A. m. ligustica workers at 2 d post infection by N. ceranae was significantly up-regulated, while those at 4, 6 and 8 d post infection by N. ceranae were significantly down-regulated, the expression levels of the target genes RRDRP in the midguts of A. m. ligustica workers at 4, 6 and 8 d post infection by N. ceranae and RCDP 42 in the midguts of A. m. ligustica workers at 2, 4, 6 and 8 d post infection by N. ceranae were significantly down-regulated, as compared to those in the midguts of A. m. ligustica workers at 1 d post infection by N. ceranae.【Conclusion】nce-miR-10660 truly exists and is expressed in N. ceranae spores. nce-miR-10660 and its target genes RRDRP and RCDP 42 are differentially expressed in A. m. ligustica workers during the infection of N. ceranae. nce-miR-10660 potentially participates in modulation of N. ceranae infection via positive regulation of the expression of RRDRP and RCDP 42.

Key words: Nosema ceranae; Apis mellifera ligustica, nce-miR-10660, target gene, expression profile