To view this video please enable JavaScript, and consider upgrading to a web browser that supports HTML5 video Movie S1 Proline locations indicated in 3D structure of importin β. A 3D rotation movie of importin β (PDB: 1ukl) molecule shown in a surface representation. 15 proline residues in A-helix are indicated in red. Prolines in the α-helix confer the structural flexibility and functional integrity of importin-β Masahiro Kumeta, Hide A. Konishi, Wanzhen Zhang, Sayuri Sakagami, and Shige H. Yoshimura J Cell Sci 2018. 131:None-None; doi: 10.1242/jcs.206326 Download Original Video