Identification and expression of the target gene SLC24A2 of oar-miR-377 and its novel SNPs effects on wool traits in sheep

Abstract

Hair follicle development is closely associated with wool traits. Current studies reveal the crucial role of microRNAs in regulating the specific gene expression by binding to target mRNA involution in hair follicle growth and development, thereby regulating the wool traits. Our previous miRNA sequencing showed that oar-miR-377 have special expression in secondary hair follicle development and SLC24A2 may be a new candidate target using bioinformatics analysis. In this study, the regulatory relationship of oar-miR-377 and its specific target gene SLC24A2 was determined in sheep fibroblasts by dual-luciferase reporter assay, RT-qPCR and western blot. The genetic variation of oar-miR-377 precursors were detected using PCR and Sanger sequencing, the association between polymorphisms of oar-miR-377 and wool quality traits were analyzed in Chinese Merino and prolific Suffolk sheep. The result showed that SLC24A2 was a target gene of oar-miR-377. A SNP (276T＞C) of oar-miR-377 upstream sequences was identified in Chinese Merino sheep and prolific Suffolk sheep, and extremely significant associated with the fiber diameter variation (P<0.01). These results suggest that oar-miR-377 promotes secondary hair follicle development by down regulation of SLC24A2 gene expression, and its SNP might be useful markers for wool quality.