Negative regulator of the innate immune response. Attenuates signaling pathways activated by Toll-like receptors (TLRs) and the DNA sensor STING/TMEM173 in response to pathogen-associated molecular patterns, such as intracellular poly(dA:dT), but not poly(I:C), or in response to DNA virus infection, including that of Herpes simplex virus 1 (HSV1) (PubMed:22863753, PubMed:24560620). May affect TLR4 signaling by acting at the level of TRAF6 ubiquitination, decreasing the activating 'Lys-63'-linked ubiquitination and leaving unchanged the degradative 'Lys-48'-linked ubiquitination (PubMed:22863753). Inhibits the PI3K-AKT-mTOR pathway possibly by directly interacting with the posphatidylinositol 3-kinase regulatory subunit p85 (PIK3R1/PIK3R2) and disrupting the association between PIK3R1/PIK3R2 and the catalytic subunit p110 (PIK3CA/PIK3CB/PIK3CD) and reducing PIK3R1/PIK3R2 activation. Via its regulation of the PI3K-AKT-mTOR pathway, controls cell proliferation, predominantly in intestinal epithelial cells (PubMed:27951586). May also affect NOD1- or NOD2-mediated NF-kappa-B activation (By similarity). Might also affect the inflammatory response by preventing NLRP3 inflammasome formation, CASP1 cleavage and IL1B maturation (By similarity). Directly interacts (via CARD) with TMEM173/STING; this interaction reduces TMEM173 trafficking to the perinuclear region in response to interferon stimulatory DNA. Also interacts, but to a lesser extent, with TBK1 (PubMed:24560620). Interacts with TRAF6; this interaction results in decreased TRAF6 'Lys-63'-linked polyubiquitination, but leaves 'Lys-48'-linked chains unchanged, promoting TRAF6 protein degradation (By similarity). Interacts with PIK3R1/PIK3R2; this interaction disrupts the association between PIK3R1/PIK3R2 and the p110 catalytic subunit PIK3CA/PIK3CB/PIK3CD and reduces PIK3R1/PIK3R2 activation (PubMed:27951586). Weakly interacts with PYCARD/ASC. Interacts with CASP1 and CASP5 (By similarity). Expressed in bone marrow-derived macrophages. The leucine-rich repeat domain may reduce the interaction with TMEM173/STING. No visible phenotype under basal conditions (PubMed:22863753). Mutant mice show an enhanced response to lipopolysaccharide (LPS)-induced endotoxic shock (PubMed:22863753). Herpes simplex virus 1-infected knockout mice exhibit enhanced innate immunity and reduced morbidity and viral load compared to wild-type animals (PubMed:24560620). Mutant mice are hyper-susceptible to colitis-associated colorectal tumorigenesis (PubMed:27951586). Belongs to the NLRP family. Extended N-terminus.