The JNK-interacting protein (JIP) group of scaffold proteins selectively mediates JNK signaling by aggregating specific components of the MAPK cascade to form a functional JNK signaling module. JIP2 inhibits IL1 beta-induced apoptosis in insulin-secreting cells. May function as a regulator of vesicle transport, through interactions with the JNK-signaling components and motor proteins (By similarity). Forms homo- or heterooligomeric complexes. Binds specific components of the JNK signaling pathway namely JNK1, JNK2, JNK3, MAP2K7, MAP3K10, MAP3K11, MAP3K12 and MAPK13. Also binds the proline-rich domain-containing splice variant of apolipoprotein E receptor 2 (ApoER2). Binds the cytoplasmic tails of LRP1 and LRP2 (Megalin). Binds the TPR motif-containing C-terminal of kinesin light chain, Klc1, pre-assembled MAPK8IP1 scaffolding complexes are then transported as a cargo of kinesin, to the required subcellular location (By similarity). Interacts with the cytoplasmic domain of APP (By similarity). Interacts with DCLK2. Interacts with TIAM1 and TIAM2 (By similarity). Interacts with FGF13; enables the interaction with MAPK13 and may regulate the MAPK8IP2 scaffolding activity. Interacts with SH3RF2 (By similarity). Accumulates in cell surface projections. Experimental confirmation may be lacking for some isoforms. Expressed mainly in the brain and pancreas, including insulin-secreting cells. In the nervous system, more abundantly expressed in the cerebellum, pituitary gland, occipital lobe and the amygdala. Also expressed in fetal brain. Very low levels found in uterus, ovary, prostate, colon, testis, adrenal gland, thyroid gland and salivary gland. Might be artifactual as it is only predicted from a genomic sequence. Belongs to the JIP scaffold family.