Negative regulator of NOD2 function. It down-regulates NOD2-induced processes such as activation of NF-kappa-B signaling, IL8 secretion and antibacterial response (PubMed:22700971). Involved in JNK signaling pathway (By similarity). Can form homodimers (via C-terminus) (PubMed:23341463). Interacts (via C-terminus) with WDR62 (via C-terminus) (PubMed:23341463, PubMed:28089251). Interacts with MAPK9 (PubMed:28089251). Interacts (via N-terminus) with NOD2; the interaction is enhanced in presence of muramyl dipeptide (MDP) (PubMed:22700971). Interacts with MAPK10 (By similarity). Not detected in the cilium. Localized around the poles of the mitotic spindle from prophase to anaphase in mitotic cells. Expressed in intestinal mucosa, where it is detected in epithelial cells, endothelial cells, smooth muscle cells and immune cells, such as lymphocytes (PubMed:22700971). Expressed in kidney (PubMed:28089251). The N-terminal WD40 domain is necessary for the interaction with NOD2 and down-regulation of NOD2 function. The disease is caused by variants affecting the gene represented in this entry.