Evidence for cooperative tandem binding of hnRNP C RRMs in mRNA processing

Model for recognition of a 10-nt RNA by two hnRNP C RRMs. (A) Scheme of two tandem RRMs binding the UC(U)₈ oligomer. Strictly uridine-specific binding pockets 3–5 (equivalent to positions 2–4 in Cieniková et al. 2014) are colored in red in the graphical model and marked as “U” in the specificity consensus, weakly specific pockets 1 and 2 are in green and labeled with “u.” (B) 2D ¹H-¹H TOCSY spectra (H5-H6 region) of the RRM-bound AUCUUUC and AUUUUUC RNAs. (C) ¹H-¹⁵N chemical shift differences (ΔCS) between the free and the RNA-bound RRM. Complex with AUUUUUC in black outline and AUCUUUC in orange.