Comparison of miRNA profiles in milk-derived extracellular vesicles and bovine mammary glands
Wenqing Li, Wanli Li, Xiaoyang Wang, Honglu Zhang, Linfeng Wang, Tengyun Gao
Abstract
Although the role of milk extracellular vesicle (EV)-derived microRNAs (miRNAs) is attracting increasing attention, little is known about the relationship between miRNAs in milk EVs and bovine mammary glands. Therefore, we investigated the miRNA profile in milk EVs and bovine mammary glands at three lactation stages (60 d, 120 d, 240 d) using small RNA sequencing. A total of 70 universally highly expressed miRNAs were identified in milk EVs and mammary glands. Comparing the types of miRNAs in milk EVs with those in mammary gland tissue, the consistency rate was over 90%. There were 4 types of highly expressed miRNAs in milk EVs but missing in the mammary gland. Correlation analysis of miRNA expression levels revealed highly significant correlations between milk EVs and mammary gland tissue (P < 0.01). Our results suggested that milk EVs had a very close relationship with bovine mammary glands at both the miRNA type and expression level.