DHX36 protein shows high affinity for G-quadruplex structures formed by GGGGCC RNA repeats. (A), (C), (E), (G) EMSA experiments were performed by annealing 20 nM of four Cy5-labeled RNA probes, r(GGGGCC)8, r(GGGGCC)4, r(GTGTCC)4, and r(CCCCGG)4, gradually from 95 °C to 25 °C and then incubating them with DHX36 protein in increasing concentrations (0, 2.5, 5, 10, 20, 40, and 80 nM) in the presence of 100 mM KCl or LiCl. The G-quadruplexes (GQ) that specifically appeared on the gels in the presence of K+ are indicated by arrows. (B), (D), (F), (H) Quantification was performed to generate the binding curves of DHX36 protein to various RNA probes in the presence of K+ or Li+ (N = 3), as indicated. Data are given as means ± SD of three independent experiments.