Neutrophil cytosol factor 1 is a 47 kDa cytosolic subunit of neutrophil NADPH oxidase. This oxidase is a multicomponent enzyme that is activated to produce superoxide anion. Mutations in this gene have been associated with chronic granulomatous disease.

A predominant transcriptional start site was identified 21 nucleotides upstream of the translation initiation codon. Transient transfections of HL60 human myeloid cells were performed with a series of 5-prime-deletion p47-phox-luciferase reporter constructs to identify the gene promoter sequences. The -224 and -86 constructs had the strongest p47-phox promoter activity, whereas the -46 construct showed a major reduction in activity and the -36 construct a complete loss of activity.