Fig. 5
From: Retroviral integration into nucleosomes through DNA looping and sliding along the histone octamer
Integration-promoted nucleosomal DNA sliding observed by single molecule FRET. a Fluorescently labelled NCP: labelled octamer (Cy5 on H2A, red) wrapped with biotinylated labelled DNA (Cy3 on exit site, blue). b NCPs are surface-immobilised on neutravidin (orange) coated biotin-PEG (yellow) slides. Intasome-induced translocation in the presence of magnesium is detected as a FRET decrease. Representative single-molecule FRET trajectories (left) and histograms (right) of proximal-only labelled NCPs c without intasome or magnesium (N = 105), d in the presence of intasome (N = 93), e in the presence of magnesium (N = 42), and f in presence of both intasome and magnesium (N = 115). A significant population shift to ~ 0.8 FRET in the presence of both intasome and magnesium. Data were collected at 100 ms/frame (10 Hz) and smoothed with a 3-point moving average. Black lines in FRET histogram are fits to two Gaussian distributions
