Abstract:

The aim of the study was to establish the expression profiles of miR-200 family in mammary gland tissues of Xinong Saanen dairy goats, and to analyze the correlation between miR-200 family and milk composition. Real-Time qPCR was used for detecting the expression of miR-200 family in mammary gland during mid-lactation and dry period. Pearson’s correlation coefficient analysis was used to determine the correlations of different miR-200 family members and goat milk composition. MiRanda, TargetScan 6.2, RNAhybrid, and PITA software were used for predicting the target genes of miR-200 family. Results showed that the expression levels of all miR-200 family members during mid-lactation were significantly higher than that during dry period (P < 0.01). Correlation analysis showed the significant correlations between miR-200a and miR-141 (P<0.05), and miR-200b and miR-200c (P<0.01). Furthermore, the expression levels of miR-200c significantly correlated with the contents of goat milk protein, solids-not-fat (SNF), and Freezing point depression (FPD) (P<0.05). We also found STAT4, a key regulator for milk fat synthesis, was a predicted target genes of miR-200a and miR-141. We concluded that miR-200 family might regulate milk protein and fatty acid synthesis in lactating goats.