Interferon (IFN) Inducible 16 (IFI16) protein belongs to a family of HIN 200 human and mouse proteins. IFI16 is a nuclear protein comtaining regulatory domains such as DNA binding domain, transcriptional regulatory domain and DAPIN/PAAD domain. IFI16 has three isotypes A, B, and C (85-95 kDa), which arise as a result of mRNA alternative splicing. All are phosphorylated on serine and threonine residues and can homo and heterodimerize. Expression is restricted to the nuclei of hematopoietic cells, fibroblasts and epithelial cells. IFI16 expression in hematopoietic cells of myeloid lineage is tightly regulated and highly induced in the differentiation and proliferation of the cell. Due to its localization in the nucleus, regulation of protein expression, and ability to bind DNA, it is assumed that IFI16 has a role in transcription regulation of cell differentiation. In addition, it was found that IFI16 can act as a transcriptional repressor and is involved in regulation and activation of p53 in cancer cells.
