Atatürk University, Faculty of Veterinary Medicine, Department of Genetics, Erzurum, Turkey.
Gene. 2020 Jun 15;743:144609. doi: 10.1016/j.gene.2020.144609. Epub 2020 Mar 24.
Bovine milk and colostrum provide essential nutrients and immunologically active factors that are beneficial to a newborn calf. Milk-and-colostrum-derived exosomes are known as the most important for cellular communication. Exosomes also contain non-coding RNA, such as microRNA. However, there is limited information about exosomal miRNA derived from the milk and colostrum of Holstein and DAK cattle. This study aimed to identify and characterize the exosomal microRNA in the milk and colostrum of Holstein and Doğu Anadolu Kirmizisi (DAK) cows. For this purpose, total RNA isolation was carried out on the milk and colostrum samples that were collected from the Holstein and DAK cattle breeds. The RNA samples were subjected to RNA sequencing and the microRNAs were determined. Lastly, gene ontology analysis was performed for target genes. A total of 795 miRNAs that were expressed differently were identified. A total of 545 of these were known miRNAs and 260 were found to be novel miRNAs. In the functional enrichment analysis, the miRNAs expressed in Holstein milk were mostly associated with milk synthesis, and those in colostrum were mostly involved in the immunity pathways. It was also observed that the miRNAs expressed in DAK milk regulated milk fat and protein metabolism, and there were miRNAs that regulated immune pathways in the colostrum. In addition to this, many novel miRNAs were defined in DAK colostrum. When the target genes of exosomal miRNA in Holstein and DAK milk and colostrum were compared, it was suggested that the DAK breed had genes that were mostly associated with the immune system. As a result, the data obtained from this study will provide beneficial contributions to potential miRNA biomarker studies for milk yield and mastitis.
牛乳和初乳为新生牛犊提供了有益的必需营养和免疫活性因子。乳和初乳衍生的外泌体被认为是细胞通讯最重要的物质。外泌体还含有非编码 RNA，如 microRNA。然而，关于荷斯坦牛和东安纳托利亚红奶牛的乳和初乳衍生的外泌体 miRNA 的信息有限。本研究旨在鉴定和表征荷斯坦牛和东安纳托利亚红奶牛乳和初乳中的外泌体 microRNA。为此，从荷斯坦牛和东安纳托利亚红奶牛品种中采集乳和初乳样本进行总 RNA 分离。对 RNA 样本进行 RNA 测序并确定 microRNA。最后，对靶基因进行了基因本体论分析。共鉴定出 795 个表达差异的 microRNA。其中 545 个是已知的 microRNA，260 个是新的 microRNA。在功能富集分析中，荷斯坦牛乳中表达的 microRNA 主要与乳合成有关，而初乳中表达的 microRNA 主要与免疫途径有关。还观察到，DAK 乳中表达的 microRNA 调节乳脂肪和蛋白质代谢，初乳中存在调节免疫途径的 microRNA。此外，在 DAK 初乳中还定义了许多新的 microRNA。当比较荷斯坦牛和 DAK 乳和初乳中外泌体 miRNA 的靶基因时，表明 DAK 品种与免疫系统相关的基因居多。因此，本研究获得的数据将为产奶量和乳腺炎的潜在 miRNA 生物标志物研究提供有益贡献。
