Domain2_TYK2

TYK2 domain 2, the JH2 pseudokinase module of tyrosine kinase 2, is offered here as a standalone recombinant protein. This region gained prominence as the allosteric site exploited by selective TYK2 inhibitors in psoriasis and other immune-mediated diseases; such compounds stabilize the pseudokinase fold and indirectly shut down catalysis by the adjacent JH1 domain. Full-length TYK2 pairs with JAK1 or JAK2 downstream of the type I interferon, IL-12 and IL-23 receptors and signals predominantly through STAT1, STAT3 and STAT4. The isolated domain is a valuable reagent for selectivity profiling, structural work and assays that distinguish pseudokinase-directed from ATP-competitive compounds.