Construction of plasmids
Full length human TYK2 cDNA template (NM003331) was purchased from YouBio (G114136), Shanghai China and subcloned to 7.1-3×Flag-CMV expression plasmid as wild type TYK2 (WT) using Seamless Cloning kit from Biomed (CL116), Beijing China. Various missense and nonsense mutation mutants of TYK2 were generated by PCR method using WT as template. Mutations were confirmed by Sanger sequencing.