Figure 8. CPSF6 peptide stabilises the CA lattice at low occupancy.

(A) Heatmaps (magenta) and median traces (black line) of the CypA intensity measured at particles with leaky capsids in the presence of 1–100 μM CPSF6p showing that the peptide stabilises the CA lattice at concentrations below the K_D of the peptide-CA hexamer interaction. The occupancy (θ) at 1 µM and 5 µM was determined experimentally (see B) while θ was estimated for higher concentratrions assuming a K_D of 50 µM. (B) Mean number of CPSF6p bound per capsid determined from CPSF6p-AF568 binding experiments. Each symbol represents an independent binding experiment, black bars indicate mean and standard deviation. (C) Heatmap (magenta) and median trace (black line) of the CypA intensity at particles with leaky or opening capsids in the presence of 100 μM CPSF6p monitored over 80 min, showing long-term stabilisation of the CA lattice.

Figure 8—figure supplement 1. Effect of CPSF6p on capsid opening.

Capsid survival curves were determined from GFP release traces. The control curve (no binder) is reproduced from Márquez et al., 2018.