PADI4

Peptidyl arginine deiminase, type IV, also known as PADI4, is a human is_associated_with::protein which in humans is encoded by the PADI4 is_associated_with::gene.

Molecular biology
The human gene is found on the short arm of Chromosome 1 near the is_associated_with::telomere (1p36.13). It is located on the Watson (plus) strand and is 55,806 bases long. The protein is 663 amino acids long with a molecular weight of 74,095 Da.

Function
This gene is a member of a gene family which encodes enzymes responsible for the conversion of is_associated_with::arginine to is_associated_with::citrulline residues. This gene may play a role in is_associated_with::granulocyte and is_associated_with::macrophage development leading to inflammation and immune response. PADI4 plays a role in the epigenetics, the deimination of arginines on histones 3 and 4 can act antagonistically to arginine methylation (Chromatin modifications and their function, Kouzarides 2007, Cell, review)

The protein may be found in oligomers and binds 5 calcium ions per subunit. It catalyses the reaction:


 * Protein L-arginine + H2O = protein L-citrulline + NH3

Subcellular and tissue distribution
It is normally found in the is_associated_with::cytoplasm, nucleus and in cytoplasmic granules of is_associated_with::eosinophils and is_associated_with::neutrophils. It is not expressed in peripheral is_associated_with::monocytes or is_associated_with::lymphocytes. It is also expressed in rheumatoid arthritis synovial tissues.