T-cell receptor
Unc-119 has also been identified in other areas in humans, such as the liver, kidneys, brain, and fibroblasts. It has also been found to play an important role within the T-cell receptor function and interleukin-5 receptor (IL-5R) Unc-119 is an essential activator of both Lck and Fyn by interacting with their SH2- and SH3-binding domains. Mutation of the Unc-119 gene has been found to severely disrupt the T-cell receptor pathway. It has been suggested to be a cause of an immunodeficiency disordered known as idiopathic CD4 lymphopenia (ICL) due to the reduced t-cell stimulation.