Reversible control of cell-level molecular timekeeping by translational switching of Cry1 expression in Cry-null SCN slices. Reversible control of cell-level molecular timekeeping by translational switching of Cry1 expression in Cry-null SCN slices. (A) Representative normalized and detrended plot of ensemble bioluminescence, recorded by a CCD camera, from an AAV-transduced Cry1,2-null SCN slice (slice C) during baseline, treatment with 1 mM AlkK (magenta), and subsequent washout. (B) Raster plot of individual cellular rhythms recorded by a CCD camera from the trace shown in A before, during, and after treatment with 1 mM AlkK. (C) The corresponding mean phase-distribution maps and Rose plots for each phase of treatment, with the clustered phases of the individual cells shown in pink histograms and the vector length depicted by the blue arrow. The number below each plot depicts the Rayleigh coefficient and therefore the degree of synchrony between cells. (D) Phase plots of cellular oscillations across the SCN slice in A and B over the first four cycles of treatment with AlkK. Note the limited phase-dispersal of rhythmic cells in cycle 1 and the progressive dispersal over subsequent cycles as the circuit spontaneously organizes its spatiotemporal structure. The asterisk denotes the position of the third ventricle. Elizabeth S. Maywood et al. PNAS doi:10.1073/pnas.1811438115 ©2018 by National Academy of Sciences