Figure 2.

In Vitro GST Pull-Down Assays Showing Interactions between AtTFIIB and Wild-Type or Mutated AtTBP2.

(A) Protein gel blot of TFIIB bound to GST-TBP beads. T7 epitope–tagged AtTFIIB was synthesized in a coupled transcription/translation (TNT) reaction by using wheat germ lysate. AtTFIIBΔC represents prematurely terminated protein, resulting in an undefined C-terminal truncation. Bands were visualized by probing the protein gel blot with the anti-T7 tag monoclonal antibody. Binding was quantified by analyzing scanned images with Scion Image software. Units on the vertical axis are arbitrary.

(B) Protein gel blot of the TBP bound to GST-TFIIB beads. AtTBP and its mutants were synthesized in a coupled TNT reaction in rabbit reticulocyte lysate. The blotting procedures and quantification of binding are as given in (A).

WT, wild type.