Associates with PYCARD/ASC and modulates its ability to collaborate with MEFV/pyrin and NLRP3/cryopyrin in NF-kappa-B and pro-caspase-1 activation. Suppresses kinase activity of NF-kappa-B inhibitor kinase (IKK) complex, expression of NF-kappa-B inducible genes and inhibits NF-kappa-B activation by cytokines and LPS. Interacts with PYCARD/ASC (via pyrin domain). Recruited to specks formed by PYCARD within the cytoplasm. Predominantly expressed in monocytes, macrophages and granulocytes. Phosphorylated.