a–c, Superimposition of the x-ray crystal structures of the Sec24C peptide (magenta) with CPSF6 peptide (blue) (a), Nup153 peptide (red) (b) and PF74 (black) (c) binding sites. d-f, Competition assays to show CPSF6 (d) and Nup153 (e) pull-downs from HeLa cell lysates by CA tubes in the absence (lane 3) and presence (lanes 4) of GST-Sec24C196–314. Representative immunoblots for CPSF6 and Nup153 are shown for the following samples. Lanes: 1, cellular lysates; 2, pelleting of cellular lysates in the absence of CA tubes; 3, pelleting of cellular lysates with CA tubes; 4, pelleting of cellular lysates with CA tubes + 2- fold excess GST-Sec24C196–314. (f), PF74 dose-dependent inhibition of interactions of GST-Sec24C196–314 with HIV-1 cores. The data (mean values +/− SD) from three independent experiments are shown. The results were analysed by Origin 2019 software to determine the IC50 value.