A functional genomics study in zebrafish to elucidate the role of thyroid hormones and deiodinases in early embryonic development.

Thyroid hormones (THs) play an essential role in vertebrate development. Research on the cellular and molecular mechanisms involved in TH dependent development has focussed mainly on later developmental stages. The aim of this project is to elucidate the role of maternal THs in early development, prior to the start of embryonic thyroid gland activity. Inhibition of intracellular TH activation by injecting morpholino antisense oligomers against type 1 and type 2 deiodinase can severely disturb early development of zebrafish embryos. Therefore we will investigate in detail the phenotype of double knockdown embryos using two complementary approaches. In one approach we will combine in vivo morphometric analyses with whole mount in situ hybridisation for a wide array of marker genes to determine which tissues, cellular processes and/or signal transduction pathways are affected. The other approach consists of comparison of the complete transcriptome via microarray analysis to identify changes in gene response in specific signal transduction pathways and the effects on other biochemical processes. The interaction between both approaches will eventually lead to a functional validation step where the most important processes will be investigated in depth by additional directed gene knockdown experiments.

Keywords:Microarray analysis, Morpholino knockdown, Zebrafish, Development, Deiodinase, Thyroid hormone

Disciplines:Endocrinology and metabolic diseases, Animal biology, Genetics