# miR-329b-5p Affects Sheep Intestinal Epithelial Cells against Escherichia coli F17 Infection

## TL;DR

This study shows that miR-329b-5p helps sheep intestinal cells resist E. coli F17 infection by improving cell adhesion, growth, and movement.

## Contribution

The study identifies miR-329b-5p as a novel microRNA that enhances resistance of sheep intestinal cells to E. coli F17.

## Key findings

- miR-329b-5p increases adhesion between E. coli F17 and intestinal epithelial cells.
- Overexpression of miR-329b-5p promotes intestinal cell proliferation and migration.
- miR-329b-5p plays a key role in defending against E. coli F17 infection in sheep.

## Abstract

Sheep diarrhea is one of the most common illnesses in sheep farming and diarrhea in sheep caused by E. coli occupies a significant proportion of them. E. coli F17 is one of the main members of E. coli causing diarrhea in sheep. This study is devoted to improving the resistance of sheep itself to E. coli F17. This study provides theoretical support for the solution of E. coli F17-caused diarrhea in sheep.

Diarrhea is the most common issue in sheep farms, typically due to pathogenic Escherichia coli (E. coli) infections, such as E. coli F17. microRNA, a primary type of non-coding RNA, has been shown to be involved in diarrhea caused by pathogenic E. coli. To elucidate the profound mechanisms of miRNA in E. coli F17 infections, methods such as E. coli F17 adhesion assay, colony counting assay, relative quantification of bacterial E. coli fimbriae gene expression, indirect immune fluorescence (IF), Cell Counting Kit-8 (CCK-8), 5-ethynyl-2′-deoxyuridine (EdU), Western blotting (WB), and scratch assay were conducted to investigate the effect of miR-329b-5p overexpression/knock-down on E. coli F17 susceptibility of sheep intestinal epithelial cells (IECs). The findings indicated that miR-329b-5p enhances the E. coli F17 resistance of sheep IECs to E.coli F17 by promoting adhesion between E. coli F17 and IEC, as well as IEC proliferation and migration. In summary, miR-329b-5p plays a crucial role in the defense of sheep IECs against E. coli F17 infection, providing valuable insights into its mechanism of action.