Figure 1.

v-Rel/IκBα complexes (A) and IκBα protein expression (B) in v-rel/ikba double transgenic thymocytes. To generate v-rel/ikba double transgenic mice, ikba homozygous transgenic mice were crossed with v-rel heterozygous transgenic mice. Both transgenes were under the control of the lck promoter. Screening of double transgenic mice was done by PCR analysis using v-rel–specific oligonucleotides. (A) Immunoprecipitations were performed as previously described (31). [³⁵S]methionine-labeled thymocytes were lysed under nondenaturing conditions, and total protein extract was immunoprecipitated with anti–v-Rel antibodies. The immunoprecipitate was denatured to dissociate the v-Rel–containing immune complex and then reprecipitated, first with IκBα and subsequently with IκBβ and v-Rel antibodies (left). The supernatant of the total protein extract treated with anti–v-Rel antibody was subsequently reprecipitated with anti-IκBα and anti-IκBβ antibodies (right). (B) The levels of IκBα protein expression were analyzed by Western blot in total protein extracts from control (w.t.), ikba transgenic, v-rel transgenic and v-rel/ikba double transgenic thymocytes.