The results of tests for EAST interaction with insulator proteins in S2 cells.

<p>(A) Co-immunoprecipitation of V5 epitope-tagged insulator proteins Su(Hw), Mod(mdg4)-67.2 (Mod-67.2), and CP190 by antibodies against the FLAG epitope fused to either EAST or its truncated forms EAST^1-1995 and EAST^933-2362. Immunoprecipitated complexes were washed several times with 150 mM KCl-containing buffers and resolved by SDS-PAGE for Western blot analysis with the indicated antibodies. InPut, input fraction (10% of lysate using for immunoprecipitation); OutPut, supernatant after immunoprecipitation; IP, immunoprecipitate. (B) Co-immunoprecipitation of FLAG-tagged EAST variants by antibodies against the V5 epitope fused to either of the insulator proteins. (C) Co-immunoprecipitation between the insulator proteins and the EAST variants fused in frame with FLAG. The S2 cells were transfected with different EAST truncated proteins fused in frame with FLAG. Immunoprecipitation was performed with antibodies raised to insulator proteins Su(Hw), Mod(mdg4)-67.2 (Mod-67.2), or CP190. The bottom panel (Ab in IP) shows the result of immunoprecipitation of target insulator proteins, which was performed in each assay. (D) Co-immunoprecipitation of Su(Hw), Mod(mdg4)-67.2, and CP190 by antibodies against the FLAG epitope fused to each of the EAST variants.