FIG. 6.

Investigation of polα-primase subunit binding to E1. In vitro association of bead-bound GST-E1 to radiolabelled p180, p68, p58, or p48 subunits was assayed as described previously. (A) In vitro translation products of each polα-primase subunit. (B) Binding of p180 to full-length GST-E1, GST-p68, and GST, demonstrating clear interaction with p68 but no interaction with GST-E1 above background levels. (C) Binding of p48, p58, and p68 to full-length GST-E1, revealing strong interaction with only the p68 subunit. The positions of molecular mass markers are indicated. The arrowheads indicate full-length IVT protein products.