Representative electromobility shift assays on 0.8% agarose gels. Effects of Imu3 binding to DNA (“a” and “c” with pUC19/Eco RI, “b” with pUC19 and “d” RNA). (A) DNA: effect of NaCl (0 to 500 mM), Imu3 concentrations 0.3, 0.6 and 1.2 μg. (B) DNA: effect of temperature (10-min incubation), Imu3 additions 0.0625 to 1.0 μg (two fold increase/step). (C) DNA: effect of Mg2+ ions, Imu3 concentrations 0.3, 0.6 and 1.2 μg. (D) RNA: Imu3 additions 0.312 to 10 μg (two fold concentration increase/step). (A, B, C, D) M: λ/Pst I DNA marker; C: control (pUC19/Eco RI alone).