Visualizing metabolic regulation using metabolic biosensors during sea urchin embryogenesis

Area of Science:

• Developmental Biology
• Cellular Metabolism
• Biochemistry

Background:

• Metabolic regulation is increasingly recognized for its dynamic influence on cellular function and development.
• Real-time in vivo analysis of metabolite activity during embryogenesis is essential to understand these dynamics.

Purpose of the Study:

• To utilize metabolic biosensors for tracking pyruvate and oxidative phosphorylation (Oxphos) dynamics during sea urchin early embryogenesis.
• To validate the accuracy of metabolic biosensors in reflecting cellular metabolic status.

Main Methods:

• Employing two metabolic biosensors: PyronicSF for pyruvate and Grx-roGFP for redox potential (indicating Oxphos).
• Conducting time-lapse imaging during sea urchin embryogenesis.
• Validating biosensor responses with pyruvate addition, PKM knockdown, DTT, and H2O2 treatments.

Main Results:

• Pyruvate levels increased in micromeres early on and remained high in ectoderm, decreasing in endomesoderm during gastrulation.
• Oxidative phosphorylation (Oxphos) signals showed an inverse trend, decreasing in micromeres and increasing in endomesoderm.
• Biosensors demonstrated faithful reflection of cellular metabolic status and spatial-temporal changes.

Conclusions:

• Metabolic regulation during embryogenesis is both temporally and spatially dynamic.
• Metabolic biosensors are valuable tools for real-time monitoring of metabolic activities in developing embryos.
• These findings provide critical insights into the role of metabolic dynamics in developmental processes.