JMJD1C is a nuclear protein that belongs to the JHDM2 family of histone demethylases. Expressed in a wide variety of tissues, JMJD1C binds iron as a cofactor and contains one JMJC domain, a TRI8H1 domain with a C2HC4-type zinc finger-like motif and a TRI8H2 domain with a TR∫ (thyroid hormone receptor ∫)-binding region. JMJD1C demethylates lysine-9 of Histone H3, thereby playing a central role in the histone code and participating in nuclear hormone receptor-based transcriptional regulation. In addition, JMJD1C plays an important role in the regulation of cell growth during development and in chromatin regulation. Due to alternative splicing events, two isoforms exist for JMJD1C. One of these isoforms functions as a coactivator for the AR (androgen receptor).