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Updated: Jun 7, 2026

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An Ex vivo Culture System to Study Thyroid Development
Published on: June 6, 2014
Thyroid hormone-responsive genes mediate otolith growth and development during flatfish metamorphosis
Summary
Thyroid hormone (TH) triggers significant growth and mineralization of flatfish otoliths. This study identifies key TH-responsive genes involved in otolith development during flatfish metamorphosis.
Area of Science:
- Developmental biology
- Comparative physiology
- Molecular endocrinology
Background:
- Flatfish larvae are bilaterally symmetrical, transforming into asymmetrical juveniles during metamorphosis.
- Thyroid hormone (TH) is known to induce otolith growth and mineralization in developing flatfish.
- The specific genes mediating TH's role in otolith development require further elucidation.
Purpose of the Study:
- To investigate the role of vestibular-specific genes in flatfish otolith development.
- To determine if these genes are responsive to TH during metamorphosis.
Main Methods:
- Gene expression analysis of vestibular-specific genes in larval flatfish.
- Treatment of larvae with TH and assessment of gene expression changes.
- Quantification of gene up-regulation during spontaneous metamorphosis.
Main Results:
- Four out of five tested vestibular-specific genes (alpha-tectorin, otogelin, otolith matrix protein, otopetrins 1 and 2) were up-regulated.
- Gene up-regulation ranged from 1.5- to 7-fold.
- Up-regulation occurred during spontaneous metamorphosis and/or after 72 hours of TH treatment.
Conclusions:
- Diverse TH-responsive genes mediate otolith growth and development in flatfish.
- These findings provide insight into the molecular mechanisms of flatfish metamorphosis and sensory system development.
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