STAT1 encodes a member of the STAT protein family. They respond to cytokines and growth factors and act as transcription activators. It mediates the expression of a variety of genes, which is thought to be important for cell viability in response to different cell stimuli and pathogens (R).

Mutations in this gene can cause immunodeficiency (R).

     From NCBI Gene: Immunodeficiency 31aMycobacterial and viral infections, susceptibility to, autosomal recessiveImmunodeficiency 31CFrom UniProt: Immunodeficiency 31C (IMD31C): A primary immunodeficiency disorder with altered immune responses and impaired clearance of fungal infections, selective against Candida. It is characterized by persistent and/or recurrent infections of the skin, nails and mucous membranes caused by organisms of the genus Candida, mainly Candida albicans. [MIM:614162] Immunodeficiency 31B (IMD31B): A disorder characterized by susceptibility to severe mycobacterial and viral infections. Affected individuals can develop disseminated infections and die of viral illness. [MIM:613796] Immunodeficiency 31A (IMD31A): A form of Mendelian susceptibility to mycobacterial disease, a rare condition caused by impairment of interferon-gamma mediated immunity. It is characterized by predisposition to illness caused by moderately virulent mycobacterial species, such as Bacillus Calmette-Guerin (BCG) vaccine, environmental non-tuberculous mycobacteria, and by the more virulent Mycobacterium tuberculosis. Other microorganisms rarely cause severe clinical disease in individuals with susceptibility to mycobacterial infections, with the exception of Salmonella which infects less than 50% of these individuals. Clinical outcome severity depends on the degree of impairment of interferon-gamma mediated immunity. Some patients die of overwhelming mycobacterial disease with lepromatous-like lesions in early childhood, whereas others develop, later in life, disseminated but curable infections with tuberculoid granulomas. IMD31A has low penetrance, and affected individuals have relatively mild disease and good prognosis. IMD31A confers a predisposition to mycobacterial infections only, with no increased susceptibility to viral infections. [MIM:614892]

     From NCBI Gene: The protein encoded by this gene is a member of the STAT protein family. In response to cytokines and growth factors, STAT family members are phosphorylated by the receptor associated kinases, and then form homo- or heterodimers that translocate to the cell nucleus where they act as transcription activators. This protein can be activated by various ligands including interferon-alpha, interferon-gamma, EGF, PDGF and IL6 . This protein mediates the expression of a variety of genes, which is thought to be important for cell viability in response to different cell stimuli and pathogens. Two alternatively spliced transcript variants encoding distinct isoforms have been described. [provided by RefSeq, Jul 2008] From UniProt: Signal transducer and transcription activator that mediates cellular responses to interferons (IFNs), cytokine KITLG/SCF and other cytokines and other growth factors. Following type I IFN (IFN-alpha and IFN-beta) binding to cell surface receptors, signaling via protein kinases leads to activation of Jak kinases (TYK2 and JAK1) and to tyrosine phosphorylation of STAT1 and STAT2. The phosphorylated STATs dimerize and associate with ISGF3G/IRF-9 to form a complex termed ISGF3 transcription factor, that enters the nucleus. ISGF3 binds to the IFN stimulated response element (ISRE) to activate the transcription of IFN-stimulated genes (ISG), which drive the cell in an antiviral state. In response to type II IFN (IFN-gamma), STAT1 is tyrosine- and serine-phosphorylated. It then forms a homodimer termed IFN-gamma-activated factor (GAF), migrates into the nucleus and binds to the IFN gamma activated sequence (GAS) to drive the expression of the target genes, inducing a cellular antiviral state. Becomes activated in response to KITLG/SCF and KIT signaling. May mediate cellular responses to activated FGFR1, FGFR2, FGFR3 and FGFR4.

The following transcription factors affect gene expression:

• p53
• STAT3
• IRF-1
• STAT1
• STAT1beta
• STAT1alpha
• STAT2
• STAT4
• STAT6

Molecular Function:

• Cadherin Binding Involved In Cell-Cell Adhesion
• Double-Stranded Dna Binding
• Enzyme Binding
• Nuclear Hormone Receptor Binding
• Protein Homodimerization Activity
• Rna Polymerase Ii Core Promoter Proximal Region Sequence-Specific Dna Binding
• Rna Polymerase Ii Core Promoter Sequence-Specific Dna Binding
• Signal Transducer Activity
• Transcription Factor Activity, Rna Polymerase Ii Core Promoter Sequence-Specific
• Transcription Factor Activity, Sequence-Specific Dna Binding
• Tumor Necrosis Factor Receptor Binding
• Identical Protein Binding

Biological Processes:

• Apoptotic Process
• Blood Circulation
• Cellular Response To Insulin Stimulus
• Cellular Response To Interferon-Beta
• Cellular Response To Organic Cyclic Compound
• Defense Response To Virus
• Interferon-Gamma-Mediated Signaling Pathway
• Jak-Stat Cascade
• Macrophage Derived Foam Cell Differentiation
• Metanephric Mesenchymal Cell Differentiation
• Metanephric Mesenchymal Cell Proliferation Involved In Metanephros Development
• Negative Regulation By Virus Of Viral Protein Levels In Host Cell
• Negative Regulation Of Angiogenesis
• Negative Regulation Of Endothelial Cell Proliferation
• Negative Regulation Of I-Kappab Kinase/Nf-Kappab Signaling
• Negative Regulation Of Mesenchymal To Epithelial Transition Involved In Metanephros Morphogenesis
• Negative Regulation Of Metanephric Nephron Tubule Epithelial Cell Differentiation
• Negative Regulation Of Transcription From Rna Polymerase Ii Promoter
• Positive Regulation Of Mesenchymal Cell Proliferation
• Positive Regulation Of Smooth Muscle Cell Proliferation
• Positive Regulation Of Transcription, Dna-Templated
• Positive Regulation Of Transcription From Rna Polymerase Ii Promoter
• Regulation Of Apoptotic Process
• Regulation Of Interferon-Gamma-Mediated Signaling Pathway
• Regulation Of Type I Interferon-Mediated Signaling Pathway
• Renal Tubule Development
• Response To Camp
• Response To Cytokine
• Response To Hydrogen Peroxide
• Response To Interferon-Beta
• Response To Mechanical Stimulus
• Response To Nutrient
• Response To Peptide Hormone
• Transcription, Dna-Templated
• Tumor Necrosis Factor-Mediated Signaling Pathway
• Type I Interferon Signaling Pathway