Promotes caspase-mediated apoptosis. This proapoptotic activity is mediated predominantly through the activation of caspase-9. May be a component of the inflammasome, a protein complex which also includes NALP2, CARD8 and CASP1 and whose function would be the activation of proinflammatory caspases. Forms complexes with other DAPIN domain-containing proteins. Interacts with CIAS1/PYPAF1 and PYDC1. Widely expressed at low levels. Detected in peripheral blood leukocytes, lung, small intestine, spleen, thymus, colon and at lower levels in placenta, liver and kidney. Very low expression in skeletal muscle, heart and brain. Detected in the leukemia cell lines HL-60 and U-937, but not in Jurkat T- cell lymphoma and Daudi Burkitt's lymphoma. Detected in the melanoma cell line WM35, but not in WM793. Not detected in HeLa cervical carcinoma cells and MOLT-4 lymphocytic leukemia cells. 3 isoforms of the human protein are produced by alternative splicing. Note: This description may include information from UniProtKB.
Molecular Function: enzyme binding; identical protein binding; interleukin-6 receptor binding; myosin I binding; protease binding; protein binding; protein homodimerization activity; Pyrin domain binding; tropomyosin binding
Biological Process: activation of innate immune response; activation of NF-kappaB transcription factor; apoptosis; defense response to Gram-negative bacterium; defense response to virus; DNA damage response, signal transduction by p53 class mediator resulting in induction of apoptosis; inhibition of NF-kappaB transcription factor; myeloid dendritic cell activation; myeloid dendritic cell activation during immune response; negative regulation of I-kappaB kinase/NF-kappaB cascade; negative regulation of interferon-beta production; neutrophil degranulation; positive regulation of actin filament polymerization; positive regulation of activated T cell proliferation; positive regulation of adaptive immune response; positive regulation of antigen processing and presentation of peptide antigen via MHC class II; positive regulation of apoptosis; positive regulation of caspase activity; positive regulation of interferon-gamma production; positive regulation of interleukin-1 beta secretion; positive regulation of interleukin-6 production; positive regulation of JNK cascade; positive regulation of phagocytosis; positive regulation of T cell activation; positive regulation of transcription factor activity; positive regulation of tumor necrosis factor production; regulation of protein stability; tumor necrosis factor-mediated signaling pathway