Fig. 14

AP1 homomer formation and no interaction between AP1 and PI. A, B Fast Lifetime images of AP1-mV in presence of AP1-mCh (depicted in A’–B’, Zoom2). Green arrows highlight nuclei with decreased lifetime. C Lifetime images of AP1-mV in presence of PI-mCh (depicted in C–C’, Zoom2). Dashed green line highlights region where AP1 and PI co-localise. No difference in lifetime between nuclei with or without acceptor could be observed. D BINDING [%] (grey) and FRET efficiencies [%] (white) for AP1-mV, AP1-mV AP1-mCh and AP1-mV PI-mCh. (Dashed blue line marks the BINDING cut-off of 10%; number of repetitions are indicated in the bottom of the plot). Data points were calculated from a respective FLIM image containing several nuclei (Zoom8 or Zoom2), but only nuclei containing both donor and acceptor were considered in FLIM image analysis of FRET samples. In half the images of AP1-mV AP1-mCh samples increased BINDING above the 10% Cut-off was measured (mean BINDING of 8.59% ± 5.37and mean FRET efficiency of 56.67% ± 19.52), while in the AP1-mV PI-mCh samples no BINDING above the 10% Cut-off could be detected (3.28% ± 3.91). Statistical groups were assigned after multiple comparison with Kruskal–Wallis and a post-hoc test using the criterium Fisher’s least significant difference (alpha parameter is 0.01). Scale bars: 40 µm