TIG3 Is a Multifunctional Regulator of Keratinocyte Differentiation and Survival

Tazarotene induced gene 3 (TIG3) is a tumor suppressor protein that regulates epidermal keratinocyte differentiation and survival. TIG3 is expressed in the upper layers of normal epidermis where it participates in halting cell proliferation and driving terminal differentiation. Reduced levels of TIG3 are observed in hyperproliferative diseases and restoration of TIG3 decreases cell survival and correlates with disease normalization. In normal epidermis, TIG3 binds to and activates type I transglutaminase resulting in cornified envelope formation and also localizes at the centrosome to halt cell proliferation by inhibiting centrosome function.