JAZF1 is a transcriptional corepressor that plays critical roles in metabolic regulation and cell differentiation. As a component of the NuA4/TIP60 complex, JAZF1 functions as a corepressor of nuclear receptor TR4, suppressing transcriptional activation through stabilization of an autorepressed conformation 1. JAZF1 regulates glucose and lipid homeostasis by repressing gluconeogenic genes and modulating expression of metabolic regulators like HNF4α 2. In endometrial stromal cells, JAZF1 safeguards cell survival and decidualization by transcriptionally repressing G0S2 through interaction with the G0S2 activator Purβ 3. The protein influences PRC2 chr7 remodeling complex function; the pathogenic JAZF1-SUZ12 fusion in low-grade endometrial stromal sarcoma dysregulates PRC2 composition and genome occupancy, altering H3K27me3 deposition and gene expression patterns critical for cell differentiation 4. JAZF1 knockout mice exhibit growth retardation, altered body composition, and muscle insulin resistance mediated through the GH-IGF-1 axis 2. Clinically, JAZF1 polymorphisms are associated with type 2 diabetes susceptibility 5, while JAZF1-SUZ12 fusions occur in approximately 50-75% of low-grade endometrial stromal neoplasms, serving as a diagnostic marker 6. Downregulation of JAZF1 in recurrent spontaneous abortion decidua correlates with defective decidualization and pregnancy loss 3.