CTCF and epilepsy: In permeabilized cell transport assays, KPNA7 binds and facilitates nuclear import of the bipartite NLS in hnRNP R and the monopartite NLS sequence in hnRNP U. The epilepsy-associated substitution, E344Q, reduces KPNA7 binding and nuclear import mediated by the NLS in hnRNP R and hnRNP U. Lastly, the DNA mutation (c.1030G > C) that generates the E344Q substitution maps to a CTCF binding site, and using fluorescence anisotropy, we determined that the mutation reduces CTCF binding ~40-fold.