FBXL10 (F-box and leucine-rich repeat protein 10), also known as Fbl10, CXXC2 (CXXC-type zinc finger protein 2), PCCX2, KDM2B, JEMMA (jumonji domain, EMSY-interactor, methyltransferase motif protein) or JHDM1B (jumonji C domain-containing histone demethylase 1B), is a nuclear protein that contains one F-box domain, a CXXC-type zinc finger, one JMJC domain, four leucine-rich repeats and one PHD-type zinc finger. FBXL10 belongs to the Fbls class of F-box proteins that contain leucine-rich repeats in addition to their F-box motif. F-box proteins are critical components of the SCF (Skp1-CUL-1-F-box protein) type E3 ubiquitin ligase complex and are involved in substrate recognition and recruitment for ubiquitination. In addition to its role in substrate recognition as a component of the E3 complex, FBXL10 functions as a dimethylation-specific demethylase, binding iron as a cofactor and demethylating lysine-36 of Histone H3. This suggests that FBXL10 plays a central role in the histone code.
