Identification of a Preferred Substrate Peptide for Transglutaminase 3 and Detection of In Situ Activity in Skin and Hair Follicles

The study identified a preferred substrate peptide, E51 (PPPYSFYQSRWV), for transglutaminase 3 (TGase 3) using a phage-displayed peptide library, demonstrating high reactivity and specificity with minimal cross-reactivity to other isozymes. Alanine substitution analysis highlighted crucial amino acids for substrate recognition. The peptide form, pepE51, confirmed its potential as a probe for detecting TGase 3 activity in situ, revealing its presence in specific layers of the epidermis and hair follicles. This research provided a valuable tool for studying TGase 3 activity and its role in skin and hair follicle physiology, aiding in the investigation of related diseases.