Fig. 5

Effect of IN/H4 mutations on the functional association between HIV-1 IN and mononucleosomes. Pull-down experiments were performed using recombinant 601 mononucleosome (125 ng in DNA) and WT IN or mutant proteins (10 pmol) under 140–240 mM NaCl (see typical experiments in Figure S5). Bound IN was detected by western blotting using a polyclonal anti-IN antibody and quantified as reported in (a) as the percentage of input precipitated under each condition. Integration assays were performed on MN (50 ng in DNA) immobilized on streptavidin beads with 400 nM of WT or mutated IN and 10 nM of 42 bp of a 5′-radiolabeled viral U5 end. The percentage of integrated product was measured as indicated in materials and methods section and is shown in (b). All values are shown as the mean ± standard deviation (error bars) of three to six independent sets of experiments. The p values were calculated by Student’s t-test and are shown as *p < 0.05 and **p < 0.005 to represent the probability of obtaining significant differences compared with the data obtained with the WT enzyme