Plays a role in T-cell signaling pathway. Isoform 2 may play a role in T-helper 2 (Th2) signaling pathway and seems to represent the first proximal signaling protein that links T-cell receptor-mediated signal to the activation of c-Maf Th2 specific factor. . This is the function of CMIP (c-Maf inducing protein, Ensembl gene identifier ENSG00000153815).