Cargando…
Homozygous STAT2 gain-of-function mutation by loss of USP18 activity in a patient with type I interferonopathy
Type I interferonopathies are monogenic disorders characterized by enhanced type I interferon (IFN-I) cytokine activity. Inherited USP18 and ISG15 deficiencies underlie type I interferonopathies by preventing the regulation of late responses to IFN-I. Specifically, USP18, being stabilized by ISG15,...
Autores principales: | , , , , , , , , , , , |
---|---|
Formato: | Online Artículo Texto |
Lenguaje: | English |
Publicado: |
Rockefeller University Press
2020
|
Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7201920/ https://www.ncbi.nlm.nih.gov/pubmed/32092142 http://dx.doi.org/10.1084/jem.20192319 |
Sumario: | Type I interferonopathies are monogenic disorders characterized by enhanced type I interferon (IFN-I) cytokine activity. Inherited USP18 and ISG15 deficiencies underlie type I interferonopathies by preventing the regulation of late responses to IFN-I. Specifically, USP18, being stabilized by ISG15, sterically hinders JAK1 from binding to the IFNAR2 subunit of the IFN-I receptor. We report an infant who died of autoinflammation due to a homozygous missense mutation (R148Q) in STAT2. The variant is a gain of function (GOF) for induction of the late, but not early, response to IFN-I. Surprisingly, the mutation does not enhance the intrinsic activity of the STAT2-containing transcriptional complex responsible for IFN-I–stimulated gene induction. Rather, the STAT2 R148Q variant is a GOF because it fails to appropriately traffic USP18 to IFNAR2, thereby preventing USP18 from negatively regulating responses to IFN-I. Homozygosity for STAT2 R148Q represents a novel molecular and clinical phenocopy of inherited USP18 deficiency, which, together with inherited ISG15 deficiency, defines a group of type I interferonopathies characterized by an impaired regulation of late cellular responses to IFN-I. |
---|