Potential Regulatory Role of MicroRNAs in the Development of Bovine Gastrointestinal Tract during Early Life

This study aimed to investigate the potential regulatory role of miRNAs in the development of gastrointestinal tract (GIT) during the early life of dairy calves. Rumen and small intestinal (mid-jejunum and ileum) tissue samples were collected from newborn (30 min after birth; n = 3), 7-day-old (n = 6), 21-day-old (n = 6), and 42-day-old (n = 6) dairy calves. The miRNA profiling was performed using Illumina RNA-sequencing and the temporal and regional differentially expressed miRNAs were further validated using qRT-PCR. Analysis of 16S rRNA gene copy numbers was used to quantify total bacteria, Bifidobacterium and Lactobacillus species. The expression of miR-143 was abundant in all three gut regions, at all time points and it targets genes involved primarily in the proliferation of connective tissue cells and muscle cells, suggesting a role in regulating rapid tissue development during the early life of calves. The expression of miR-146, miR-191, miR-33, miR-7, miR-99/100, miR-486, miR-145, miR-196 and miR-211 displayed significant temporal differences (FDR

本研究旨在探讨微小RNA（miRNA）在乳牛早期生长发育过程中对胃肠道（GIT）发育的潜在调控作用。研究者从出生后30分钟（n=3）、7日龄（n=6）、21日龄（n=6）和42日龄（n=6）的乳牛中采集了瘤胃和小肠（中空肠和回肠）组织样本。采用Illumina RNA测序技术对miRNA进行鉴定，并通过实时定量逆转录聚合酶链反应（qRT-PCR）对时间点和区域差异表达miRNA进行进一步验证。利用16S rRNA基因拷贝数分析来量化总细菌、双歧杆菌和乳杆菌等菌种。miR-143在三个肠道区域的所有时间点均有丰富表达，其靶基因主要涉及结缔组织细胞和肌细胞的增殖，暗示其在调节乳牛早期快速组织发育过程中发挥着调控作用。miR-146、miR-191、miR-33、miR-7、miR-99/100、miR-486、miR-145、miR-196和miR-211的表达呈现出显著的时序差异（FDR