miR-122/449a and their target genes expression levels detection in bull testicular Sertoli cells. A, miR-122 and DUSP4, PDK4 expression levels were detected in Sertoli cells that transfected with miR-122 mimics, miR-122 inhibitor and miR-shNC (**p<0.01); B, miR-449a and target gene FKBP1B expression levels were detected in cells that transfected miR-449a mimics, miR-449a inhibitor and miR-shNC (**p<0.01); C, Western blot analysis for DUSP4, PDK4 and FKBP1B after miR-122 and miR-449a transfection.