IFNAR2-gene

IFNAR2 is the acronym for "Interferon Alpha/Beta Receptor 2" a gene located on chromosome 21q22.11. IFNAR2 encodes a type I membrane protein that forms one of the two chains of a receptor for interferons alpha and beta. Binding and activation of the receptor stimulates Janus protein kinases, which in turn phosphorylate several proteins, including STAT1 and STAT2. Several transcript variants have been found for this gene, encoding at least two different isoforms.

Diseases associated with IFNAR2 include:

Immunodeficiency 44 and Immunodeficiency 45.

Related pathways include, in the context of an immune response, the IFN alpha/beta pathway. Gene Ontology (GO) annotations associated with this gene include protein kinase binding and type I interferon binding. A paralog of this gene is "ENSG00000249624", a protein-coding gene whose function is still largely unclear.

The protein encoded by the IFNAR2 gene belongs to the type II cytokine receptor family. The IFNAR2 protein is a membrane protein that forms one of the two subunits of the receptor for type I interferons (alpha and beta). Following IFN binding and receptor dimerization, juxtaposition of JAK1 and TYK2 leads to increased kinase activity through transphosphorylation and subsequent STAT protein recruitment. Receptor-bound STAT proteins are successively phosphorylated, dimerize, and translocate to the nucleus, where ISG transcription is initiated after binding of ISRE or GAS sites. In response to IFN-I, three active complexes are formed that play critical roles in transcriptional regulation:

• a STAT1/STAT2 heterodimer associated with IRF9, known as ISGF3, binds the ISRE motif.
• With the same mode of action, an alternative complex composed of STAT2 homodimers and IRF9 (STAT2/IRF9).
• STAT1 homodimers (known as GAF), which specifically recognize the GAS sequence (see Fig.).

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