Figure 3. The effect of p12 mutations on the biophysical properties of the Mo-MLV intra-virion CA core.

(A) Purified wild type or p12 mutant Mo-MLV VLPs were spun through a layer of detergent into a 10–42% (w/w) linear sucrose gradient. Fractions were harvested and analysed by immunoblotting using an anti-CA antibody (note: fractions 1–3 are diluted by 1∶13 to reduce the immunoblot signal, *: this input was run on a separate gel from the gradient fractions). Representative immunoblots are shown for wild type and each of the p12 mutants. (B) For each experiment, the sucrose density of the fraction containing the peak CA signal was measured, and the change in density compared to peak CA fraction for wild type virions was calculated. The mean and range from two independent experiments are displayed in the histogram.