Meeting Abstract
Thyroid hormone is critical for the normal development and regulation of a variety of cellular and organismal processes, particularly those involving the skeletal system. Mouse and rat models have been traditionally used to study thyroid hormone, but the fast generation time and ease of genomic manipulation of zebrafish makes them an excellent tool to investigate the effects of thyroid hormone disruption. Therefore, a thorough anatomical assessment of the differences in the adult hypo-, eu-, and hyperthyroid zebrafish is important for those who wish to use zebrafish as a model organism for thyroid research. We studied the effects of thyroid disruption on skeletal development using both transgenic hypothyroid and mutant hyperthyroid lineages of Danio rerio. Anatomical analyses revealed that in hypothyroid zebrafish, there are significant anomalies in development of the dermatocranium. Specifically, parietal and frontal bones failed to properly fuse. Moreover, the radials of the pectoral fin also underwent improper development. In addition, hyperthyroid zebrafish exhibit greatly enlarged neural spines, haemal spines, and dentaries. Our results suggest that thyroid hormone plays a key role in skeletogenesis within the entire body of the zebrafish. By thoroughly investigating and comparing the anatomy of hypo-, eu-, and hyperthyroid zebrafish, we are better able to understand the role of thyroid hormone in skeletal development in vertebrates in general.
