Fig. 7: Super resolution SMLM imaging of apoptotic and non-apoptotic neurons in mouse cortical cryosections confirms high chromatin compaction during apoptosis in vivo.

a Widefield imaging of aCasp3 immunosignal (left) allowed the identification of apoptotic and non-apoptotic neurons, and SMLM reconstruction of DNA molecules stained with Sytox Orange (right) are shown for four representative cells imaged in cortical tissue samples from a P6 mouse. Scale: 5 µm. b Representative detailed views on inserts highlighted in a revealed that compaction of chromatin into clusters is higher in nuclei of neurons with aCasp3 signal (red) as compared to nuclei without caspase 3 activation (blue). Scale 0.5 µm. c Intensity plots of representative lines from details in b confirmed the higher compaction of chromatin in nuclei of neurons with the aCasp3 signal. d Distribution of the log-normalized Voronoi densities of aCasp3-positive (red, n = 6 cells) and -negative neurons (blue, n = 7 cells). To account for different number of localizations and cells under each condition, the area under the curve is normalized to 1 and the probability density function is plotted.