Quantitative measures of clock protein dynamics in the mouse suprachiasmatic nucleus extends the circadian time-keeping model.

ABSTRACT: The suprachiasmatic nucleus (SCN) synchronises circadian rhythmicity (~24 h) across the body. The SCN cell-autonomous clock is modelled qualitatively as a transcriptional-translational feedback loop (TTFL), with heteromeric complexes of transcriptional activator and repressor proteins driving cyclical gene expression. How these proteins really behave within the SCN, individually and in relation to each other, is poorly understood. Imaging SCN slices from a novel array of knock-in reporter mice, we quantify the dynamic behaviours of combined repressors PERIOD2 (PER2) and CRYPTOCHROME1 (CRY1), and activator BMAL1. We reveal a spectrum of protein-specific intracellular and spatiotemporal behaviours that run counter to the qualitative TTFL model. We also show that PER and CRY1 exert independen

SUBMITTER: Smyllie NJ 

PROVIDER: S-EPMC12218236 | biostudies-literature | 2025 Jul

REPOSITORIES: biostudies-literature