MicroRNA-146b negatively affects bovine embryo development and quality

Area of Science:

• Reproductive biology
• Molecular biology
• Developmental biology

Background:

• MicroRNAs (miRNAs) within extracellular vesicles (EVs) are vital for embryo development.
• Molecular mechanisms governing blastocyst development and quality remain largely undefined.
• Extracellular vesicles (EVs) secreted by bovine embryos contain differentially expressed miRNAs.

Purpose of the Study:

• To investigate the role of miR-146b in bovine embryo development and quality.
• To determine the functional impact of miR-146b on blastocyst formation and apoptosis.
• To identify genes regulated by miR-146b during early embryonic development.

Main Methods:

• RT-qPCR to quantify miR-146b expression in embryos and EVs.
• Supplementation of embryo culture media with miR-146b mimics and inhibitors.
• Transcriptomic analysis of treated embryos to assess gene expression changes.

Main Results:

• miR-146b was upregulated in non-blastocyst embryos and their secreted EVs.
• miR-146b mimics decreased embryo quality and blastocyst rates, while inhibitors improved quality.
• miR-146b regulated genes involved in apoptosis, cell differentiation, and transcription.

Conclusions:

• miR-146b is overexpressed in poor-quality bovine embryos and their EVs.
• miR-146b negatively regulates embryo development and promotes apoptosis.
• miR-146b is a potential biomarker and therapeutic target for improving embryo quality.