IRF9

IRF9 (Interferon Regulatory Factor 9) is a protein that in humans is encoded by the IRF9 gene. It is a member of the interferon regulatory factors (IRFs) family, which are transcription factors that play a crucial role in the immune system.

Function

IRF9 is a key component of the interferon-stimulated gene factor 3 (ISGF3) complex, which is responsible for the transcriptional regulation of genes induced by type I interferon. The ISGF3 complex is composed of IRF9 and the STAT1-STAT2 heterodimer. Upon stimulation by type I interferons, this complex translocates to the nucleus and binds to interferon-stimulated response elements (ISRE) in the promoters of interferon-stimulated genes (ISGs), leading to their transcription.

Clinical significance

Mutations in the IRF9 gene have been associated with severe viral diseases due to impaired type I interferon responses. Moreover, IRF9 has been implicated in the pathogenesis of autoimmune diseases such as systemic lupus erythematosus and rheumatoid arthritis.

See also

• Interferon regulatory factors
• Interferon
• STAT1
• STAT2

External links

• IRF9 at the National Center for Biotechnology Information