Recombinant VP4 induces dose-dependent membrane permeability.

<p>Liposomes containing carboxyfluorescein (CF) at self-quenching concentration, were mixed with VP4His at the indicated final concentrations. Membrane permeability resulting in leakage and dequenching of CF was detected by fluorescence measurements (excitation 492 nm/emission 512 nm) recorded every 30 seconds. Data shown is representative of multiple experiments (n>3). The end point fluorescent signal induced by 5000 nM VP4His was equivalent to 70–80% of the total release induced by addition of 0.5% Triton X-100.