The SCD5 Gene Modulates Adipogenic Differentiation via the WNT5B Signaling Pathway in Xinjiang Brown Cattle

This study investigated the role of SCD5 in bovine preadipocyte proliferation and adipogenic differentiation. SCD5 overexpression suppressed proliferation, reducing the percentage of EdU-positive cells and overall cell viability (p < 0.05). It also downregulated proliferative factors CDK1 and CDK2 (p < 0.05), and reduced lipid accumulation (p < 0.001) along with key adipogenic markers PPARγ, C/EBPα, and FABP4 (p < 0.01). Conversely, SCD5 knockdown promoted these processes. Mechanistically, SCD5 overexpression downregulated WNT5B (p < 0.05), while knockdown had the opposite effect. Silencing WNT5B significantly decreased β-catenin transcription (p < 0.05), total protein (p < 0.05), and phosphorylation (p < 0.001). In conclusion, our findings identify SCD5 as a novel negative regulator of bovine preadipocyte proliferation and differentiation, which exerts its function through the WNT5B/β-catenin signaling axis. This discovery elucidates previously uncharacterized regulatory mechanisms underlying adipogenesis in livestock species.