The function of SYNCRIP mutants involved in pri-let-7a interaction and processing. (A) A schematic representation of domain structure of SYNCRIP and the mutants. (AcD) Acidic domai, (RRM) RNA recognition motif. (B) RNA-EMSA assay using biotin-labeled pri-let-7a-1. Increasing concentration of purified recombinant his-ΔC, ΔN, ΔN + C, RRM1–2, RRM2–3 are indicated. (C) Binding affinity was analyzed by Graphpad Prism (GraphPad Software, Inc.) using a nonlinear regression model. (D) In vitro cleavage assay using pri-let-7a-1 as substrate. The pri-let-7a-1 was incubated with Drosha immunoprecipitates (Drosha-IP) or additionally supplemented with an increasing amount of purified recombinant SYNCRIP mutants as indicated.
