Isolation and Molecular Cloning of Epidermal and Hair Follicle-Specific Peptidylarginine Deiminase Type III from Rat

The study focused on isolating and cloning the peptidylarginine deiminase (PAD) type III enzyme, which was specifically found in the epidermis and hair follicles of rats. Researchers purified the enzyme from 2-day-old rat epidermis, achieving a 600-fold purification with a 23% recovery rate. The enzyme's molecular weight was determined to be 76,000. The full-length cDNA encoding rat PAD type III was cloned and sequenced, revealing a 1,995 base open reading frame encoding 664 amino acids. The sequence showed 51% homology with rat PAD type II, with a highly conserved C-terminal region. The cloned gene was expressed in Escherichia coli, producing an enzyme with both enzymatic activity and immunoreactivity. The specific expression of PAD type III in the epidermis and hair follicles was confirmed through RT-PCR assays.