Copyright information:Taken from "Complex interactions of HIV-1 nucleocapsid protein with oligonucleotides"Nucleic Acids Research 2006;34(2):472-484.Published online 24 Jan 2006PMCID:PMC1351370.© The Author 2006. Published by Oxford University Press. All rights reserved Solutions of 100 nM NC were incubated with varying amounts of different oligonucleotides for at least 60 min. These solutions were then passed over an SPR surface containing 327 RU's of (TG) and the initial slope of the SPR profile, representing the initial rate of binding to the immobilized (TG), was measured. The open squares represent preincubation with 0.1, 0.25, 0.5, 1.0, 2.5, 5, 10, 25 and 50 µM (A); open triangles: preincubation with 2.5, 5.0, 10, 25, 50, 100, 250, 500, 1000 and 5000 nM (TG); open circles: preincubation with 20, 40, 60, 80, 100, 300, 500 and 1000 nM (A)(TG)(A); closed circles: preincubation with 20, 40, 60, 80, 100, 300, 500 and 1000 nM (TG)(A)(TG); closed triangles: preincubation with 0.1, 0.25, 0.5, 1.0, 2.5, 5, 10 and 25 µM (TG). The lines are fits to a 4-parameter logistic equation, as described in Supplementary Data, yielding the values shown in . Asterisks highlight the two curves in which IS is greater than zero.