Bovine Pre-adipocyte Adipogenesis Is Regulated by bta-miR-150 Through mTOR Signaling

Area of Science:

• Molecular Biology
• Animal Science
• Biochemistry

Background:

• MicroRNAs (miRNAs) are key regulators in biological processes, with miR-150 implicated in cancer.
• Bovine miR-150 (bta-miR-150) was identified as downregulated in steer vs. bull adipose tissue, but its function was unknown.

Purpose of the Study:

• To investigate the function of bta-miR-150 in cattle adipogenesis.
• To elucidate the molecular mechanisms underlying bta-miR-150's role in bovine adipocyte differentiation and proliferation.

Main Methods:

• Overexpression and inhibition of bta-miR-150 in bovine adipocytes.
• Analysis of adipocyte differentiation markers, cell proliferation assays (EdU staining), and lipid droplet quantification.
• RNA sequencing (RNA-seq) and Weighted Gene Co-expression Network Analysis (WGCNA) to identify signaling pathways and target genes.

Main Results:

• Bta-miR-150 negatively regulates adipocyte differentiation and promotes proliferation.
• Overexpression of bta-miR-150 increased expression of proliferation markers (CDK1, CDK2, PCNA) and EdU-positive cells, while reducing lipid accumulation.
• RNA-seq and WGCNA identified dysregulation of the mammalian target of the rapamycin (mTOR) signaling pathway. AKT1 was identified as a direct target of bta-miR-150, with effects on its phosphorylation.

Conclusions:

• Bta-miR-150 plays a significant role in inhibiting bovine adipogenic differentiation and promoting proliferation.
• The mTOR signaling pathway and AKT1 are involved in bta-miR-150's regulatory effects.
• Bta-miR-150 has potential applications in improving the beef industry through modulation of adipogenesis.