Protein arginine deiminase 3 (PAD3) catalyzes the conversion of arginine residues to citrulline within its cellular protein substrates, which include S100A3, trichohyalin, and filaggrin, resulting in the loss of a positive charge, which can alter protein structure and/or function. It exists as a homodimer and is composed of a C-terminal catalytic domain and an N-terminal domain that contains two immunoglobulin G (IgG) subdomains. PAD3 is primarily expressed by differentiated keratinocytes in the epidermis and hair follicles where it has roles in the shaping and mechanical strengthening of hair. It is also expressed by neural stem cells where it modulates cell death by regulating the nuclear translocation of apoptosis-inducing factor (AIF), in mammary glands where it citrullinates proteins during lactation, and cancer cells where it promotes cancer cell invasion. Mutations in PADI3 are associated with uncombable hair syndrome. Cayman''s PAD3 Monoclonal Antibody (Clone 4E5) can be used for ELISA and Western blot (WB) applications. The antibody recognizes PAD3 at ~74 kDa from human samples.
