Single-cell analysis of circadian dynamics in tissue explants

Area of Science:

• Cell Biology
• Systems Biology
• Biophysics

Background:

• In vivo molecular dynamics tracking is crucial for understanding cellular interactions.
• Existing tissue imaging methods have limitations in observation duration and sample type.
• In situ analysis of peripheral circadian signaling in single cells remains largely uncharacterized.

Purpose of the Study:

• To develop and validate an experimental and computational setup for long-term single-cell tracking in intact tissues.
• To investigate the in situ dynamics of the peripheral circadian clock in individual cells.
• To compare single-cell clock properties with population rhythms.

Main Methods:

• Utilized a wide-field microscope and a reporter mouse model.
• Developed custom software for multi-day cell tracking.
• Measured circadian signaling in hundreds of cells across two tissues.

Main Results:

• Successfully tracked single-cell transcriptional reporter dynamics for over one week in intact tissue.
• Characterized oscillatory properties of individual peripheral circadian clocks.
• Assessed the maintenance and comparison of single-cell clock properties to population rhythms.

Conclusions:

• The developed approach enables long-term, in situ single-cell analysis of molecular dynamics.
• Provides novel insights into the heterogeneity and maintenance of peripheral circadian clocks.
• Suggests potential for quantitative characterization of signaling pathways in explant models.