miR-17-5p in bovine oviductal fluid affects embryo development

Area of Science:

• Reproductive biology
• Molecular biology
• Genomics

Background:

• MicroRNAs (miRNAs) are crucial regulators of gene expression.
• Bovine oviductal fluid (OF) contains extracellular vesicles with miRNAs.
• The role of OF-miRNAs in early bovine embryonic development is not fully understood.

Purpose of the Study:

• To identify miRNAs in bovine OFs.
• To investigate the effect of miR-17-5p on bovine embryonic development.
• To elucidate the regulatory mechanisms of miR-17-5p in embryonic development.

Main Methods:

• Small RNA sequencing (RNA-seq) of extracellular vesicles from OFs.
• RT-qPCR to analyze miRNA expression in oviductal epithelial cell culture medium.
• In vitro culture of zona pellucida-free bovine embryos with miR-17-5p mimic.
• Dual-luciferase assay and immunostaining to confirm miR-17-5p function.
• RNA-seq of treated embryos to identify differentially expressed genes (DEGs).
• Ingenuity pathway analysis (IPA) for pathway and upstream regulator prediction.

Main Results:

• 242 miRNAs were identified in bovine OF extracellular vesicles.
• miRNA abundance in OFs increased during the luteal phase.
• miR-17-5p mimic treatment improved embryonic development to the blastocyst stage.
• RNA-seq identified DEGs in treated embryos, suggesting affected pathways.
• IPA identified miR-17 as a significant upstream regulator.

Conclusions:

• Bovine OF contains a diverse repertoire of miRNAs.
• miR-17-5p in OFs plays a regulatory role in bovine embryonic development.
• miR-17-5p influences embryonic development by targeting specific genes and pathways.