IFN-gamma R1

IFN-gamma R1, one of the subunit of IFN-gamma receptor, is a receptor for IFN-gamma. IFN-gamma R1 can associates with IFN-gamma R2 to form a functional receptor. Upon binding with IFN-gamma, IFNγR1 and IFNγR2 oligomerize and transphosphorylate[1]. Then, JAK1 and JAK2 are phosphorylated and activated, and STAT1 is recruited to the receptor complex. The phosphorylation of IFNγR1 creates a docking site for STAT1. Phosphorylated STAT1 leads to dimerization and translocates to the nucleus, where it regulates the expression of IFN-responsive genes (e.g. CD54)[2]. Human IFN-gamma R1 consists of extracellular domain (E18-G245), helical domain (S246-I266), and cytoplasmic domain (C267-S489). Human IFN-gamma R1 shares 50% aa sequence identity with mouse. IFN-gamma R1 is constitutively expressed on the surface of almost all cells[1]. IFN-gamma R1 plays a critical role in antimicrobial, antiviral, and antitumor responses. Mutations in the gene IFNGR1 which encodes the IFN-gamma R1 cause a primary immunodeficiency and leads to mycobacterial infection, such as Mendelian susceptibility to mycobacterial disease (MSMD)[2].