Lysine-specific demethylase 2A (KDM2A) also known as F-box and leucine-rich repeat protein 11 (FBXL11) is an

enzyme Enzymes () are proteins that act as biological catalysts by accelerating chemical reactions. The molecules upon which enzymes may act are called substrates, and the enzyme converts the substrates into different molecules known as products. A ...

that in humans is encoded by the ''KDM2A''

gene In biology, the word gene (from , ; "...Wilhelm Johannsen coined the word gene to describe the Mendelian units of heredity..." meaning ''generation'' or ''birth'' or ''gender'') can have several different meanings. The Mendelian gene is a ba ...

. KDM2A is a member of the superfamily of

alpha-ketoglutarate-dependent hydroxylases Alpha-ketoglutarate-dependent hydroxylases are a major class of non-heme iron proteins that catalyse a wide range of reactions. These reactions include hydroxylation reactions, demethylations, ring expansions, ring closures, and desaturations. Func ...

, which are non-haem iron-containing proteins.

Function

This gene encodes a member of the

F-box protein F-box proteins are proteins containing at least one F-box domain. The first identified F-box protein is one of three components of the SCF complex, which mediates ubiquitination of proteins targeted for degradation by the 26S proteasome. Core c ...

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 In chemistry, phosphorylation is the attachment of a phosphate group to a molecule or an ion. This process and its inverse, dephosphorylation, are common in biology and could be driven by natural selection. Text was copied from this source, wh ...

-dependent

ubiquitination Ubiquitin is a small (8.6 kDa) regulatory protein found in most tissues of eukaryotic organisms, i.e., it is found ''ubiquitously''. It was discovered in 1975 by Gideon Goldstein and further characterized throughout the late 1970s and 1980s. Fo ...

. The F-box proteins are divided into 3 classes: Fbws containing

WD-40 WD-40 is an American brand and the trademark of a penetrating oil manufactured by the WD-40 Company based in San Diego, California. The formula for WD-40 was invented for the Rocket Chemical Company as early as 1953 before it evolved into ...

domains, Fbls containing

leucine-rich repeats A leucine-rich repeat (LRR) is a protein structural motif that forms an α/β horseshoe fold. It is composed of repeating 20–30 amino acid stretches that are unusually rich in the hydrophobic amino acid leucine. These tandem repeats commo ...

, and Fbxs containing either different protein-protein interaction modules or no recognizable motifs. The protein encoded by this gene belongs to the Fbls class and, in addition to an F-box, contains at least 6 highly degenerated leucine-rich repeats. FBXL11/KDM2A is a

histone H3 Histone H3 is one of the five main histones involved in the structure of chromatin in eukaryotic cells. Featuring a main globular domain and a long N-terminal tail, H3 is involved with the structure of the nucleosomes of the 'beads on a stri ...

lysine 36

demethylase Demethylases are enzymes that remove methyl (CH3) groups from nucleic acids, proteins (particularly histones), and other molecules. Demethylases are important epigenetic proteins, as they are responsible for transcriptional regulation of the genom ...

enzyme. The enzymatic activity of FBXL11/KDM2A relies on a conserved JmjC domain in the

N-terminus The N-terminus (also known as the amino-terminus, NH2-terminus, N-terminal end or amine-terminus) is the start of a protein or polypeptide, referring to the free amine group (-NH2) located at the end of a polypeptide. Within a peptide, the ami ...

of the protein that co-ordinates iron and alphaketoglutarate to catalyze

demethylation Demethylation is the chemical process resulting in the removal of a methyl group (CH3) from a molecule. A common way of demethylation is the replacement of a methyl group by a hydrogen atom, resulting in a net loss of one carbon and two hydrogen at ...

via a hydroxylation based mechanism. It has recently been demonstrated that a ZF-CxxC DNA binding domain within FBXL11/KDM2A has the capacity to interact with non-methylated DNA and this domain targets FBXL11/KDM2A to CpG island regions of the genome where it specifically removes histone H3 lysine 36 methylation. This mechanism acts to create a

chromatin Chromatin is a complex of DNA and protein found in eukaryotic cells. The primary function is to package long DNA molecules into more compact, denser structures. This prevents the strands from becoming tangled and also plays important roles in r ...

environment at CpG islands that highlights these regulatory elements and differentiates them from non-regulatory regions in large complex mammalian genomes. In a study in mouse hepatocytes, this gene was shown to regulate hepatic gluconeogenesis.

Function

References

Further reading