This gene encodes a protein which activates NADPH oxidases, enzymes which catalyze a reaction generating reactive oxygen species. The encoded protein contains four N-terminal tetratricopeptide domains and a C-terminal Src homology 3 domain. Interaction between the encoded protein and proteins in the oxidase regulatory complex occur via the tetratricopeptide domains. Multiple transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Dec 2011]