Journal: Nature Communications
Article Title: Quantifying the dynamics of the oligomeric transcription factor STAT3 by pair correlation of molecular brightness
Figure Lengend Snippet: Chromatin accessibility regulated STAT3 dimer-to-tetramer transition (cpCOMB analysis). ( a ) Chromatin organization in HeLa cells stained with Hoechst 33342 after no treatment, 18 h after addition of 400 nM of trichostatin A (loosened chromatin) and 30 min after addition of 5 μg ml −1 of actinomycin D (compacted chromatin). ( b ) Merged STAT3-GFP and STAT3-mCherry intensity images of control, trichostatin A- and actinomycin D-treated live HeLa cells. Scale bar, 5 μm. ( c ) STAT3-GFP and STAT3-mCherry fluorescence intensity within the plane in which the line scan was acquired. The nuclear boundary is indicated by the Hoechst 33342 stain. ( d ) Pseudocoloured brightness maps for STAT3-GFP in control, trichostatin A- and actinomycin D-treated HeLa cells. Dark green pixels represent monomers, light green pixels dimers and red pixels tetramer. ( e ) cpCOMB carpets in control, trichostatin A- and actinomycin D-treated live HeLa cells. White dashed circles highlight tetramer formation. CTYO, cytoplasm; Max, maximum; Min, minimum; NUC, nucleus.
Article Snippet: Loosening of chromatin was carried out by treating the HeLa cells transiently transfected with STAT3-GFP and STAT3-mCherry, with trichostatin A (400 nM, Abcam) for 18 h. Compacting of chromatin was carried out by treating the HeLa cells transiently transfected with STAT3-GFP and STAT3-mCherry, with actinomycin D (5 μg ml−1 , a concentration known to stop class III transcription, Sigma Aldrich) for 30 min.
Techniques: Staining, Fluorescence