DDRGK1 interacts with IκBα.

(A) Immunoprecipitation (IP) analysis of the interaction of Flag-tagged DDRGK1 with endogenous IκBα. 293T cells were transfected Flag-tagged DDRGK1 construct or a control vector. Cell lysates were immunoprecipitated with anti-Flag resin and then analyzed by immunoblotting with IκBα and Flag antibodies. 5% of each cell lysate was loaded as input. (B) Immunoprecipitation (IP) analysis of the interaction of Flag-tagged IκBα with endogenous DDRGK1. 293T cells were transfected Flag-tagged IκBα construct or control vector. Cell lysates were immunoprecipitated with anti-Flag resin and then analyzed by immunoblotting with DDRGK1 and Flag antibodies. 5% of each cell lysate was loaded as input. (C) Diagram of full-length (Flag-IκBα) and three truncation mutant constructs (Flag-IκBα-1, Flag-IκBα-2, Flag-IκBα-3). (D) The N-terminal portion of IκBα is sufficient for its interaction with DDRGK1. Flag-tagged full-length or three truncation mutant constructs of IκBα were transiently transfected into 293T cells. The Flag-tagged full-length and mutant IκBα were immunoprecipitated with anti-FLAG resin and then immunoblotted with Flag and DDRGK1 antibodies.