STAT3 Inhibits Cell Proliferation at Least in Part Via Directly Negatively Regulating FST Gene Expression

Three years ago, a study was conducted to understand the transcriptional regulation of the Follistatin (FST) gene in sheep hair follicles, given its significant association with wool quality traits. The study found a conserved putative binding site for the signal transducer and activator of transcription 3 (STAT3) in the sheep FST promoter region. Experimental results showed that STAT3 inhibited the activity of the FST promoter, and its binding site mutation lessened this inhibitory effect. Moreover, STAT3 was found to directly bind to the FST promoter. Functionally, FST and STAT3 had opposing roles in cell proliferation. Overexpression of FST promoted cell proliferation, while overexpression of STAT3 inhibited it, accompanied by a significant reduction in FST gene expression. The study concluded that STAT3 directly negatively regulates the sheep FST gene and inhibits cell proliferation, contributing to the understanding of hair follicle development and wool trait formation.