KDM2B

KDM2B is broadly and highly expressed in embryonic tissues (especially in the developing central nervous system of vertebrates). Expression of KDM2B is also retained in most organs in adults. The protein is present in the nucleoplasm and is enriched in the nucleolus where it binds the transcribed region of ribosomal RNA to represses the transcription of ribosomal RNA genes which inhibits cell growth and proliferation. == Structure ==

KDM2B protein has several domains including a JmjC domain that has a histone demethylase activity demethylating trimethylated Lys-4 and dimethylated Lys-36 of histone H3. KDM2B specifically recognizes and bind non-methylated DNA in CpG islands through its ZF-CxxC DNA binding domain. KDM2B consequently recruits the non-canonical polycomb repressive complex 1.1 (ncPRC1) to unmethylated CpG islands via a direct interaction with BCOR and PCGF1 leading to the mono-ubiquitylation of histone H2A on K119 and gene repression. == Function ==

This gene encodes a member of the F-box protein family which is characterized by an approximately 40 amino acid motif, the F-box. The F-box proteins constitute one of the four subunits of ubiquitin protein ligase complex called SCFs (SKP1-cullin-F-box), which function in phosphorylation-dependent ubiquitination. The F-box proteins are divided into 3 classes: Fbws containing WD-40 domains, Fbls containing leucine-rich repeats, and Fbxs containing either different protein-protein interaction modules or no recognizable motifs. The protein encoded by this gene belongs to the Fbls class. Multiple alternatively spliced transcript variants have been found for this gene, but the full-length nature of some variants has not been determined. == Clinical significance ==

Loss of KDM2B leads to severe developmental defects (growth defects in the brain, including failure of neural tube closure and craniofacial malformations, hematopoietic development) leading to embryonic lethality == References ==