Figure 1.

Reb1 purification. (a) Gel-filtration elution profile of Reb1 on Superdex 75 16/60 in buffer consisting of 20 mM Tris–HCl pH 7.5, 200 mM NaCl, 5 mM TCEP, 1 mM EDTA, 10% glycerol. (b) 12% SDS–PAGE of pooled fractions stained with Coomassie Blue. Lane 1, molecular-weight markers (labeled in kDa); lane 2, Reb1. (c) Binding isotherm of the fluorescein-labeled Ter3 DNA site at 5 nM with Reb1. Reactions were performed at 20°C in an ISS PC1 fluorimeter. Data were analyzed using a single binding-site model using nonlinear fitting with Origin.