TG1 is a type of protein known as a transglutaminase, which plays a crucial role in various biological processes. It is involved in the cross-linking of proteins, helping to stabilize their structure and function. TG1 is particularly important in the skin, where it contributes to the formation of the epidermal barrier, protecting against environmental damage. In addition to its role in skin health, TG1 is also studied for its involvement in certain diseases. Abnormal activity of TG1 can be linked to conditions such as psoriasis and celiac disease. Understanding TG1's functions may lead to new therapeutic approaches for these and other related disorders.