Peptidyl arginine deiminase 1 (PAD1) is a calcium-dependent enzyme that catalyzes the conversion of arginine residues to citrulline within its cellular protein substrates, resulting in the loss of a positive charge, which can alter protein structure and/or function.1,2 It exists as a monomer and is composed of a C-terminal catalytic domain and two N-terminal immunoglobulin-like (Ig-like) domains.2 PAD1 is primarily expressed in uterine and epidermal cells and generally localized in the cytosol.3 PAD1 citrullinates non-histone proteins, such as keratin, filaggrin, and MEK1, as well as histone H3 at arginine 2 (H3R2), H3R8, H3R17, and H4R3, to regulate epidermal cell progression and embryonic development.4,5,6 The catalytic activity of PAD1 is lost by deleting the first six N-terminal amino acids.2 Decreased Padi1 expression or Pad1 inhibition reduces citrullination of H3R2, H3R8, H3R17, and H4R3 and inhibits primary mouse embryo preimplantation development.7 PADI1 mRNA is overexpressed in tumor tissue from patients with triple-negative breast cancer (TNBC), and PAD1 promotes proliferation and epithelial-to-mesenchymal transition (EMT) in a variety of TNBC cell lines in vitro and in mouse xenograft models.8 Cayman's PAD1 Monoclonal Antibody (Clone 6B4) can be used for ELISA and Western blot (WB) applications. The antibody recognizes PAD1 at approximately 74 kDa from human samples.WARNING This product is not for human or veterinary use.
