NALP3 is a component of the innate immune system that functions as a pathogen recognition receptor (PRR) that recognizes pathogen-associated molecular patterns (PAMPs). NALP3 together with the adaptor ASC protein PYCARD forms a caspase-1 activating complex known as the NALP3 inflammasome. NALP3 in the absence of activating signal is kept in an inactive state complexed with HSP90 and SGT1 in the cytoplasm. NALP3 inflammasome detects danger signals such as crystallineuric acid and extracellular ATP released by damaged cells. These signals release of HSP90 and SGT1 from and recruit ASC protein and caspase-1 to the inflammasome complex.