Antisense Morpholino-mediated knockdown of type 3 iodothyronine deiodinase in the embryonic zebrafish (Danio rerio)

Abstract

Event Abstract Back to Event Antisense Morpholino-mediated knockdown of type 3 iodothyronine deiodinase in the embryonic zebrafish (Danio rerio) Marjolein Heijlen1*, Camila V. Esguerra2, Alexander D. Crawford2 and Veerle M. Darras1 1 Catholic University of Leuven, Department of Biology, Faculty of Science, Belgium 2 Catholic University of Leuven, Department of Pharmaceutical Sciences, Faculty of Pharmaceutical Sciences, Belgium Although the pivotal role of thyroid hormones (THs) in vertebrate development has been widely documented, little information is available on their role in early embryogenesis. Early teleost embryos rely on the maternal TH deposit in the egg yolk, consisting predominantly of T4. In adult zebrafish, as in most other vertebrates, a tight control of intracellular T3 levels is achieved by the combined action of the three types of iodothyronine deiodinases (D1-D3). Recently, our team investigated the importance of the two Ds capable of T4 to T3 conversion, D1 and D2, during early embryogenesis in zebrafish. This research showed that D2 is the major contributor to TH activation in developing zebrafish embryos (1). We have now inhibited the expression of the TH inactivating enzyme, D3, by antisense morpholino-mediated knockdown. To estimate the impact of D3 knockdown on the rate of embryonic development, three morphological indices were measured: otic vesicle length, tail length and pigmentation index. The increase in otic vesicle length and the decrease in tail length and pigmentation index were all indicative of an aberrant development. Additional morphological abnormalities observed in some embryos were pericardial edema, flattening of the head, curved tail and an overall decrease in size. To control for a possible induction of a p53-dependent cell death pathway, which is the major off-targeting effect of morpholinos, we repeated the experiments with concurrent knockdown of p53. Since this did not rescue the phenotype, we can conclude that the observed defects are indeed D3-dependent. Our present results indicate that next to intracellular TH activation also local inactivation by D3 is essential for normal early development in zebrafish embryos. References (1) Walpita, C.N., A.D. Crawford, and V.M. Darras, Combined antisense knockdown of type 1 and type 2 iodothyronine deiodinases disrupts embryonic development in zebrafish (Danio rerio). Gen Comp Endocrinol, 2009. 166(1): p. 134-41. Keywords: comparative endocrinology Conference: 25th Conference of the European Comparative Endocrinologists, Pécs, Hungary, 31 Aug - 4 Sep, 2010. Presentation Type: Conference Presentation Topic: Comparative endocrinology Citation: Heijlen M, Esguerra CV, Crawford AD and Darras VM (2010). Antisense Morpholino-mediated knockdown of type 3 iodothyronine deiodinase in the embryonic zebrafish (Danio rerio). Front. Endocrinol. Conference Abstract: 25th Conference of the European Comparative Endocrinologists. doi: 10.3389/conf.fendo.2010.01.00030 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 26 Aug 2010; Published Online: 29 Aug 2010. * Correspondence: Miss. Marjolein Heijlen, Catholic University of Leuven, Department of Biology, Faculty of Science, Leuven, Belgium, marjolein.heijlen@bio.kuleuven.be Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Marjolein Heijlen Camila V Esguerra Alexander D Crawford Veerle M Darras Google Marjolein Heijlen Camila V Esguerra Alexander D Crawford Veerle M Darras Google Scholar Marjolein Heijlen Camila V Esguerra Alexander D Crawford Veerle M Darras PubMed Marjolein Heijlen Camila V Esguerra Alexander D Crawford Veerle M Darras Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.