α-Family karyopherins recognize and bind to the WW-NLS. (A) The schematic diagram illustrates the karyopherin-mediated nuclear import and highlights the cNLS-binding region and the WW-binding motifs on KPNA1–7. Basically, KPNB1 is responsible for the nuclear import of cargoes containing the cNLS under scaffold by KPNAs, while the other importins as well as biportins directly recognize the NLS other than cNLS. (B) The structures exhibit the positions of PPxY/F and xPxPP motifs on KPNA1 in a self-inhibitory state (the intramolecular IBB-bound state) and an open state (the bipartite cNLSs-bound state), respectively. (C) The WW domains from different proteins are pulled down by the PPxF motif fused to the Fc fragment of IgG in HEK293T cells. (D) The WW domain from different proteins is pulled down by the xPxPP motif fused to the Fc fragment of IgG in HEK293T cells. (E) The co-IP experiment shows the interaction of FLAG-tagged KPNA1-3 and KPNB1 with GFP-tagged tandem WW region of YAP1 in HEK293T cells. (F) The co-IP experiment shows the interaction of FLAG-tagged KPNA1-3 with GFP-tagged WW domain of PQBP1 in HEK293T cells. (G) The co-IP experiment shows the interaction of FLAG-tagged KPNA1-3 with GFP-tagged WW domain of PIN1 in HEK293T cells. (H) The co-IP experiment shows the interaction of GFP-tagged WW domain with FLAG-tagged KPNA1 and the P5A mutant bearing mutations of the WW-binding motifs in HEK293T cells. TCL, total cell lysates. Source data are available for this figure: SourceData F4.