Figure 1.

E2FC and DPB Proteins Form a Heterodimer in Vivo.

(A) Protein gel blot analysis of several independent lines (MYC-DPB^OE) that overexpress the MYC-DPB protein using the antibody against the MYC epitope. The arrows indicate the two specific bands identified. The asterisk indicates an unspecific cross-reacting band.

(B) Total protein extract from MYC-DPB^OE plants were immunoprecipitated using agarose beads coupled to IgGs against the MYC epitope (IP αMYC) or agarose beads coupled to IgGs against the hemagglutinin (HA) epitope as a control (IP α Control). The precipitated proteins were examined by protein gel blot analysis using the antibody against MYC (MYC-DPB) or the affinity-purified anti-E2FC (E2FC) IgGs.

(C) Recombinant E2FC protein was used in pull-down assays with GST or GST-DPB. The pulled-down proteins were examined by protein gel blot analysis using the IgGs against E2FC.

(D) CDKA-phosphorylated radiolabeled E2FC protein was used in pull-down assays with GST or GST-DPB. Bound proteins were fractionated by SDS-PAGE, and the dried gel was exposed to detect the radiolabeled E2FC (E2FC-³²P).