Jumonji-containing proteins (JmjC) are enzymes with roles in chromatin regulation. They are specifically involved in histone demethylation and contribute to the control of gene expression and epigenetic states. Jumonji-containing proteins primarily function as histone demethylases, catalysing the removal of methyl groups from specific lysine or arginine residues on histone tails. This activity is essential for regulating the epigenetic marks on chromatin. Depending on the specific lysine/arginine residue and the degree of methylation removed, histone demethylation can result in either gene activation or repression. By demethylating histones, Jumonji-containing proteins directly influence gene expression. For example, JARID1A (also known as KDM5A) demethylates di- and trimethylated H3K4 (H3K4me2/3), marks usually associated with active gene promoters. This process promotes transcriptional repression and thereby contributes to gene silencing. Jumonji-containing proteins are thought to be important for cell fate determination during development by regulating the expression of genes essential for the differentiation of various cell types. JMJD3 (also known as KDM6B) for example demethylates H3K27me3, a repressive histone mark, at lineage-specific gene loci, allowing for the activation of genes required for differentiation. For example, by removing repressive H3K27me3 marks on Brachyury, a transcription factor that is essential for mesoderm formation, JMJD3 promotes mesoderm commitment. Some Jumonji-containing proteins are also involved in the DNA damage response by regulating the chromatin structure around DNA lesions. For example, KDM4A can demethylate H3K36me3, a mark involved in maintaining genomic stability. This demethylation helps recruit DNA repair factors to damaged sites. For example, KDM4A-mediated demethylation of H3K36me3 can promote the alternative DNA repair pathway non-homologous end joining (NHEJ), an error-prone repair process that directly ligates broken double-strand breaks (DSBs) in DNA. By demethylating H3K36me3 near the DSB, KDM4A may create a more permissive chromatin environment for the recruitment and binding of NHEJ repair factors, such as Ku70/Ku80 and DNA ligase IV, at the site of DNA damage. The Jumonji domain, characterized by its conserved sequence motifs, is responsible for the demethylase activity of these proteins. The catalytic mechanism involves the oxidation of the methyl group to generate an unstable intermediate, subsequently hydrolysed to remove the methyl group. This process requires cofactors such as Fe (II) and α-ketoglutarate, making these enzymes dependent on both oxygen and the TCA cycle. Jumonji-containing proteins exhibit specificity for methylation states and lysine/arginine residues on histone tails. Thus, different members of this protein family target distinct histone marks. For example, KDM4 family members target H3K9me3 and H3K36me3, whilst KDM6 family members target H3K27me3 and H3K4me3. The activity of Jumonji-containing proteins is also regulated by post-translational modifications, protein-protein interactions, and co-factors. For example, PHF8, a Jumonji-containing protein, is regulated by phosphorylation, and its demethylase activity is enhanced in the presence of its substrate and cofactors. Activation of PHF8 by phosphorylation can be mediated by various kinases, including protein kinase A (PKA), protein kinase C (PKC), and cyclin-dependent kinases (CDKs). Thus, Jumonji-containing proteins are essential regulators of chromatin, with their primary role being histone demethylation, thereby contributing to gene regulation, cell differentiation, and the DNA damage response. We provide a wide product range of research tools for investigating Jumonji containing proteins, including JMJD6 antibodies. Explore our full Jumonji containing proteins product range below and discover more, for less.