JHDM1Bs

JHDM1Bs, or JHDM1B-related proteins, denote a group of Jumonji domain-containing histone demethylases in the JHDM1 subfamily. Members are characterized by a catalytic JmjC domain and are involved in epigenetic regulation by removing methyl groups from lysine residues on histone tails. This activity alters chromatin structure and gene expression patterns. The "B" designation marks a paralogous subset within the JHDM1 family, and multiple genes or isoforms have been described in vertebrates, often referred to as JHDM1Ba, JHDM1Bb, etc.

Biochemical properties: JHDM1Bs require transition metal ions such as Fe(II) and cofactors such as α-ketoglutarate to perform demethylation. The reaction can proceed on different methylation states (mono-, di-, tri-), depending on substrate and context. Proteins may contain auxiliary domains that influence subcellular localization, substrate preference, and interaction with other chromatin modifiers.

Biological roles: They participate in development, differentiation, and cellular responses by regulating gene expression programs. They are involved in chromatin remodeling and can influence DNA repair pathways or cell cycle control through epigenetic mechanisms.

Clinical relevance: Altered expression or mutation of JHDM1Bs has been linked to various cancers and neurodevelopmental disorders in some studies. Because histone demethylases are druggable, JHDM1B family members are explored as potential targets for epigenetic therapies, though clinical applications require further validation.

Evolution and research status: The JHDM1 family is conserved across vertebrates, with ongoing research to map substrate specificity, regulatory networks, and physiological roles of JHDM1Bs.