The Role of miR-326-3p in Regulating Differentiation and Thermogenesis Genes in Goat Brown Adipocytes

<b>Background</b>: Brown adipose tissue (BAT) is indispensable for producing heat and contributes critically to the survival of neonatal mammals. MicroRNAs (miRNAs) are small noncoding RNAs that serve as key post-transcriptional regulators, playing a crucial role in regulating BAT development and thermogenesis. However, the role of miR-326-3p in goat brown adipocytes remains largely unclear. <b>Methods</b>: Primary brown adipocytes were isolated from goat perirenal adipose tissue and subjected to gain and loss-of-function assays using miR-326-3p mimics and inhibitors. Lipid accumulation, thermogenic-related genes, and mitochondrial gene expression were quantified by Oil Red O staining and qRT-PCR. Target prediction and dual-luciferase reporter assays were performed to validate direct interaction between miR-326-3p and FGF11. <b>Results</b>: Expression profiling demonstrated that miR-326-3p is more enriched in brown adipose tissue (BAT) than in white adipose tissue (WAT), and the expression level gradually decreases with adipocyte differentiation. miR-326-3p overexpression significantly inhibited lipid droplet accumulation and the expression of genes associated with differentiation, thermogenesis, and mitochondria, including <i>PPARγ</i>, <i>FABP4</i>, <i>UCP1</i>, and <i>PGC1α</i>, whereas inhibition produced the opposite effect. Bioinformatic prediction and dual-luciferase reporter assays further identified fibroblast growth factor 11 (<i>FGF11</i>) as a direct target of miR-326-3p. <b>Conclusions</b>: These findings reveal that miR-326-3p negatively regulates the differentiation and expression of thermogenic-related genes of goat brown adipocytes, uncovering a novel miR-326-3p-FGF11 regulatory axis.