kC->I as a function of [RNP] for dCas9 (gray) and dSpRY (purple) using the same DNA and RNA sequences in Figure 2A. Error bars were calculated assuming Poisson statistics. Solid lines are fit of kC->I vs. RNP concentration ([RNP]), assuming a linear model with kon,eff(dCas9) for dCas9 and a hyperbolic saturation model with initial affinity Kd,init(dSpRY) and maximal unwinding rate kopen(dSpRY) for dSpRY. The equations for each model are provided as insets. The faded dashed line has a slope kon,eff(dSpRY) = kopen(dSpRY)/Kd,init(dSpRY) and shows the linear dependence of kC->I on dSpRY [RNP] in the low [RNP] regime. See also Note S1 in the supplemental information for model selection, Table S1 for rate constants, Table S2 for fit details, Figures S3B–S3D for example raw traces, and Figures S3F–S3H for other rate constants (kI->C, kI->O, and kO->I).
