Developmental expression of type 2 deiodinase in the chicken hypothalamus

Abstract

Event Abstract Back to Event Developmental expression of type 2 deiodinase in the chicken hypothalamus P. Mohácsik1, T. Füzesi1, E. Hadadi1, E. Szabó1, M. Doleschall1, P. Egri1, Z. Liposits1, C. Fekete1 and B. Gereben1* 1 Hungarian Academy of Sciences, Institute of Experimental Medicine, Hungary Thyroid hormone is an essential factor of brain development and function. Thyroxine is a pro-hormone that needs to be converted to 3,5,3’-triiodothyronine (T3) to be able to bind the thyroid hormone receptors. Type 2 deiodinase (D2) is the key enzyme that generates T3 in the brain. D2 is abundantly expressed in hypothalamic tanycytes that are special glial cells lining the floor and walls of the third ventricles. In chicken, adenohypophysis starts promoting thyroidal secretion at embryonic day (E) 11.5, while thyroid hormones start exerting their negative feedback effect on the TSH production only at E19. It can be hypothesized that a special pattern of D2-mediated T3 generation in developing hypothalamus could be required for the development of T3 dependent negative feedback. Using in situ hybridization, we detected D2 mRNA in tanycytes in the floor and walls of the third ventricle at E13 in the chicken mediobasal hypothalamus. At this stage, the mRNA of the Nkx-2.1 transcription factor could be also detected in tanycytes while it was absent from the perivascular space where D2 expressing astrocytes are present. Promoter studies in U87 glioma cells proved that Nkx-2.1 can induce transcription of the cdio2 gene. In conclusion, the appearance of Nkx-2.1 mediated D2 expression in chicken tanycytes well before the onset of feedback suggests that D2 expression in these cells could be required, but not sufficient to initiate T3 dependent negative feedback in the hypothalamus. Keywords: Neuroendocrinology, Neuroscience Conference: 13th Conference of the Hungarian Neuroscience Society (MITT), Budapest, Hungary, 20 Jan - 22 Jan, 2011. Presentation Type: Abstract Topic: Neuroendocrinology Citation: Mohácsik P, Füzesi T, Hadadi E, Szabó E, Doleschall M, Egri P, Liposits Z, Fekete C and Gereben B (2011). Developmental expression of type 2 deiodinase in the chicken hypothalamus. Front. Neurosci. Conference Abstract: 13th Conference of the Hungarian Neuroscience Society (MITT). doi: 10.3389/conf.fnins.2011.84.00177 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: 03 Mar 2011; Published Online: 23 Mar 2011. * Correspondence: Dr. B. Gereben, Hungarian Academy of Sciences, Institute of Experimental Medicine, Budapest, Hungary, gereben@koki.hu 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 P. Mohácsik T. Füzesi E. Hadadi E. Szabó M. Doleschall P. Egri Z. Liposits C. Fekete B. Gereben Google P. Mohácsik T. Füzesi E. Hadadi E. Szabó M. Doleschall P. Egri Z. Liposits C. Fekete B. Gereben Google Scholar P. Mohácsik T. Füzesi E. Hadadi E. Szabó M. Doleschall P. Egri Z. Liposits C. Fekete B. Gereben PubMed P. Mohácsik T. Füzesi E. Hadadi E. Szabó M. Doleschall P. Egri Z. Liposits C. Fekete B. Gereben 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.