Study on expression of miR-21-5p and targeted lipid metabolism genes in mammary tissues of Dehong dairy buffalo.

The aim of the experiment was to investigate the expression of the miR-21-5p gene and its target genes in the mammary tissues of Dehong dairy buffalo. The healthy Dehong dairy buffalo with the same feeding conditions, the same parity, similar age and middle lactation were divided into a high milk fat rate group (group H), a medium milk fat rate group (group M) and a low milk fat rate group (group L). Three dairy buffaloes were selected in each group, and breast tissues were collected after slaughter to extract total RNA. Bioinformatics methods were employed to predict the target genes of miR-21-5p. The expression levels of miR-21-5p and its target genes were quantified by fluorescence quantitative PCR, and correlation analysis was conducted with previously determined milk fat content. The results showed that the possible target genes of miR-21-5p were AGPAT6 and GPAM. The expression level of miR-21-5p in mammary tissue of Dehong daily buffalo in the group L was extremely higher than that in the group M and group H (P<0.01). The results of the correlation analysis showed that the expression level of miR-21-5p was extremely and negatively correlated with the target gene AGPAT6 (P<0.01), and significantly and negatively correlated with the expression level of the target gene GPAM (P<0.05). In the mammary tissue of Dehong dairy buffalo, the expression level of miR-21-5p was significantly and negatively correlated with the milk fat protein interaction network showed that the interaction between AGPAT6 and GPAM was the strongest. The results indicate that miR-21-5p may influence milk fat 31460649) synthesis by negatively regulating the expression of the target genes AGPAT6 and GPAM, and consequently influencing the milk fat percentage. [ABSTRACT FROM AUTHOR]