An accessible microfluidic perfusion platform for time-restricted control of zebrafish embryonic patterning

Area of Science:

• Developmental biology
• Biomedical engineering
• Pharmacology

Background:

• Vertebrate embryonic development involves sequential somite segmentation from tail tissue.
• Fibroblast growth factor (Fgf)/ERK signaling gradient from the tailbud instructs this segmentation via an oscillatory "segmentation clock".

Purpose of the Study:

• To develop a cost-effective, reproducible live imaging setup for precise, automated drug delivery in zebrafish embryos.
• To investigate the role of Fgf/ERK signaling in somite segmentation and rescue segmentation in clock-deficient mutants.

Main Methods:

• A 3D-printed chamber for zebrafish embryo orientation and controlled fluid perfusion.
• A programmed syringe pump and Arduino-controlled servo motors for automated, periodic drug delivery and fluid exchange.
• Live imaging of fluorescently labeled zebrafish embryos at single-cell resolution during drug perturbations.

Main Results:

• The system successfully recapitulated somite segmentation in clock-deficient zebrafish mutants through periodic delivery of an Fgf/ERK inhibitor.
• This periodic drug delivery entrained oscillations in the Fgf/ERK signaling gradient, leading to reconstituted somite formation.
• The setup allows for real-time observation of cellular dynamics and decision-making under controlled pharmacological conditions.

Conclusions:

• The developed live imaging system provides a versatile platform for studying vertebrate development and cellular responses to controlled drug delivery.
• This technology enables the interrogation of signaling pathways and rescue of developmental defects in vivo.
• The system is broadly applicable to biomedical research focused on developmental dynamics and pharmacological interventions.