HMGR overexpression and interference affects the expression of steroidogenic genes and cholesterol content in bovine intramuscular adipocytes

Background:Previously, we found that mevalonic acid stimulates HMGR expression in bovine intramuscular adipocytes, and influences adipocyte differentiation. However, it remains unclear whether there is any direct link between HMGR, steroidogenic genes, and cholesterol content. RNA-Seq was conducted to determine the differences between the gene expression profiles of bovine adipocytes containing different HMGR expression constructs. Results:In total, 10 234 differentially expressed genes (DEGs) were found. Of these, 35 and 6 DEGs between the control and the overexpression groups were functionally related to lipid and energy metabolisms, respectively. Additionally, 43 and 8 DEGs between the control and the HMGR inhibition groups were related to lipid and energy metabolism. Additionally, several DEGs related to lipid and energy metabolism were identified between the HMGR overexpression group and the HMGR interference group. Several DEGs correlated positively or negatively with overexpression or inhibition of HMGR. We also found that, following activation or inhibition of the HMGR gene, AMPK and SIRT1 had opposite expression patterns in bovine intramuscular adipocytes. Interestingly, the HMGR gene was downregulated when HMGR was overexpressed, and upregulated when HMGR was inhibited. Conclusion:Our findings establish a theoretical understanding of signaling pathways involved in cholesterol synthesis by elucidating the relationships between key genes.