Cyclin-dependent kinase 5 (Cdk5) activity is modulated by light and gates rapid phase shifts of the circadian clock

The circadian clock enables organisms to synchronize biochemical and physiological processes over a 24-hour period. Natural changes in lighting conditions, as well as artificial disruptions like jet lag or shift work, can advance or delay the clock phase to align physiology with the environment. Within the suprachiasmatic nucleus (SCN) of the hypothalamus, circadian timekeeping and resetting rely on both membrane depolarization and intracellular second-messenger signaling. Voltage-gated calcium channels (VGCCs) facilitate calcium influx in both processes, activating intracellular signaling pathways that trigger Period (Per) gene expression. However, the precise mechanism by which these processes are concertedly gated remains unknown. Our study in mice demonstrates that cyclin-dependent kinase 5 (Cdk5) activity is modulated by light and regulates phase shifts of the circadian clock. We observed that knocking down Cdk5 in the SCN of mice affects phase delays but not phase advances. This i..., Mouse behavior, locomotor activity monitoring, light treatment, RNA extraction and cDNA synthesis, qRT-PCR, Immunofluorescence, Virus production and stereotactic injections, protein extraction, Immunoprecipitation, Western blotting, In vitro kinase assay, Cell Culture, Fiber photometry, Calcium imaging, FRET imaging, , # Data from: Cyclin-dependent kinase 5 (Cdk5) activity is modulated by light and gates rapid phase shifts of the circadian clock

[https://doi.org/10.5061/dryad.8sf7m0d0d](https://doi.org/10.5061/dryad.8sf7m0d0d)

## Description of the data and file structure

### Figure 1

1A. The *.PGN files are a graphic representation of the actogram used to analyze and quantify the period length and phase shift measured at different ZTs (14, 24, 10) of scramble and sh Cdk5 mice entrained to light dar cycles 12:12.

1B. The *.pzfx includes the dataset obtained from actograms analyzed with ClockLab. It shows the circadian period length difference between scramble and shCdk5 mice entrained to light-dark cycles 12:12.

1C. The *.pzfx includes the dataset obtained from actograms analyzed with ClockLab. It shows the circadian phase shift difference between scramble and sh Cdk5 mice entrained to light-dark cycles 12:12.

1D. The *.PGN files are a graphic representation of the actogram used to analyze and ...