Figure 5.

Effects of NTR truncations on C. thermophilum Brr2^NC variants. (A) Binding of N-terminal Brr2^NC truncations to U4/U6 di-snRNA monitored by electrophoretic mobility shift assays. Values represent means ± SEMs of at least 2 independent experiments. K_d values were obtained by fitting quantified binding data to a single exponential Hill function (fraction bound = A[protein]ⁿ/([protein]ⁿ+K_dⁿ); A – fitted maximum of RNA bound; n – Hill coefficient). (B) Time courses of U4/U6 unwinding by Brr2^NC variants. Data represent means ± SEM of at least 3 independent experiments. Amplitudes and unwinding rates were obtained by fitting the quantified data to a first-order reaction (fraction unwound = A[1-exp{-k_u t}]; A – amplitude of the reaction; k_u – apparent first-order rate constant of unwinding; t – time). (C) U4/U6 di-snRNA affinities and unwinding parameters of Brr2^NC variants. Values represent means ± SEM of at least 2 independent experiments.