Figure 2.

Artemis interacts directly with DDB2. (A and B) Artemis does not interact with DDB1 in vitro. Artemis and DDB1 labeled with ³⁵S-methionine were expressed in vitro by transcription-coupled translation. Artemis and DDB1 were mixed and IPed with DDB1 antibody (A, upper part) or Artemis antiserum (B) as indicated. A control experiment shows the interaction between DDB1 and Cul4A (A, lower part). Bound proteins were eluted, separated by SDS-PAGE and detected by autoradiography. (C) Artemis directly interacts with GST-DDB2 in vitro. Artemis and GST-DDB2 were in vitro translated and labeled with ³⁵S-methionine. Synthesized proteins were mixed and incubated as indicated for immunoprecipitation. Parts show the autoradiography of labeled proteins. (D) Purified recombinant Artemis and DDB2 directly interact. GST-Artemis, GST and MBP-DDB2 proteins were expressed and purified from E. coli. Purified proteins were mixed as indicated, and pull-down assays were performed and analyzed by immunoblotting.