Crystallographic analysis of the recognition of a nuclear localization signal by the nuclear import factor karyopherin alpha

A study was conducted to characterize the crystal structures of the arm-repeat region of Saccharomyces cerevisiae karyopherin in unliganded form and in complex with a peptide. Multiple isomorphous replacement was carried out to determine structure phases. Results indicated that the repeated arm motifs support a complex set of interactions with the backbone and side chains of the nuclear localization signals.