Acts as a positive regulator of T-cell maturation and inflammatory function. Required for several functions of T-cells in both the CD4(+) and the CD8(+) compartments and this includes expression of cell surface markers of activation, proliferation, and cytokine production in response to specific or non-specific stimulation and during the course of infection with the mouse malaria parasite Plasmodium berghei (PubMed:25403443). Enhances NK cell cytotoxicity by positively regulating polarization of microtubule-organizing center (MTOC) to cytotoxic synapse, lytic granule transport along microtubules, and dynein-mediated clustering to MTOC (By similarity). Interacts with HSPA5 and stabilizes the interaction between HSPA5 and ERN1, leading to suppression of ERN1-induced JNK activation and endoplasmic reticulum stress-induced apoptosis (PubMed:21289099). Homodimer (By similarity). Interacts with DOCK8 (By similarity). Interacts (via C-terminus) with intact microtubules (By similarity). Interacts with dynein-dynactin motor complex (By similarity). Interacts (via C-terminus) with HSPA5 (PubMed:21289099). Abundantly expressed in immune cells, including both CD4(+) and CD8(+) T-cells and in myeloid cells (at protein level) (PubMed:25403443). Expressed in endothelium (at protein level) (PubMed:21289099). Expressed specifically in spleen, bone marrow, lymph nodes and thymus (PubMed:25403443). Expressed in liver and heart (PubMed:21289099). Mice show defects in T-cell functions including impaired maturation, significantly reduced activation, reduced cell division as well as impaired cytokine production in response to specific or non-specific stimulation and during the course of infection with the mouse malaria parasite Plasmodium berghei. Belongs to the CCDC88 family.