Developing the Gnotobiotic Stickleback Model
Our lab has successfully developed methods for generating and maintaining germ-free (gnotobiotic) threespine stickleback, opening new avenues for studying host-microbiome interactions under controlled conditions.
Why Gnotobiotic Fish?
Gnotobiotic animals - those with no microbes or only known microbes - are essential for understanding: - How specific microbes affect host biology - The role of microbiomes in development and immunity - Host genetic effects on microbiome assembly - Causality in host-microbe associations
Until now, gnotobiotic techniques were limited to a few model organisms like mice and zebrafish. Extending these methods to stickleback leverages their natural genetic variation and ecological diversity.
Technical Innovation
Developing gnotobiotic stickleback required overcoming several challenges:
- Sterile derivation: Removing all microbes from eggs without damaging development
- Sterile maintenance: Keeping fish microbe-free for months
- Validation: Confirming absence of microbes using multiple methods
- Controlled colonization: Adding specific microbes to study their effects
Our protocol, refined over two years, achieves >95% success rate in generating germ-free fish that develop normally.
Research Applications
This system enables us to: - Test how specific host genes affect microbiome assembly - Measure microbe-specific effects on host gene expression - Study immune system development in the absence of microbes - Perform controlled evolution experiments with defined microbial communities
First Results
Initial experiments reveal: - Germ-free stickleback have altered intestinal development - Immune gene expression differs dramatically without microbes - Colonization with different bacteria produces distinct host responses - Host genotype influences which microbes successfully colonize
Open Science
We’re preparing a detailed protocol paper and video tutorial to help other labs adopt this system. This tool will accelerate host-microbiome research across the stickleback community.
Funding: This work is supported by NIH grant R01GM130777 and the META Center for Systems Biology.
Contact us for protocol details or collaboration opportunities.