DEVELOPMENTAL AND THYROID HORMONE-INDUCED EXPRESSION OF DNA METHYLTRANSFERASES AND METHYL-CPG BINDING PROTEINS IN XENOPUS TADPOLE BRAIN DURING METAMORPHOSIS

Abstract

Event Abstract Back to Event DEVELOPMENTAL AND THYROID HORMONE-INDUCED EXPRESSION OF DNA METHYLTRANSFERASES AND METHYL-CPG BINDING PROTEINS IN XENOPUS TADPOLE BRAIN DURING METAMORPHOSIS Yasuhiro Kyono1, 2 and Robert J. Denver1* 1 University of Michigan, Molecular, Cellular and Developmental Biology, United States 2 University of Michigan, Neuroscience Graduate Program, United States Postembryonic brain development is critically dependent on thyroid hormone (T3), which influences neural cell proliferation, migration, differentiation, morphology and function. Thyroid hormone is known to promote neurogenesis, and recent findings showed that proteins that methylate the genome, DNA methyltransferases (DNMTs), and proteins that bind to methylated DNA, methyl-CpG binding proteins (MBDs), also play critical roles in cell lineage specification and neurogenesis in the developing brain. We hypothesized that T3 promotes neurogenesis through its regulation of DNMT and MBD expression. To test this we investigated the developmental expression and T3 regulation of DNMT (dnmt1 and dnmt3a) and MBD (mecp2, mbd1-4 and kaiso) genes in the brain of tadpoles of Xenopus laevis. We microdissected tadpole brains and analyzed mRNAs in the preoptic area/diencephalon by RTqPCR. We found that mRNAs for dnmt1, dnmt3a, mbd3 and kaiso were upregulated during spontaneous metamorphosis. Treatment of premetamorphic tadpoles with T3 (5nM) caused a time-dependent upregulation of each of these genes. Dnmt3a and mbd3 mRNAs were upregulated by 12 hr; whereas, dnmt1 and kaiso mRNAs were upregulated by 24 hr after T3 treatment. Using in situ hybridization histochemistry, we confirmed the developmental and T3-dependent increase in dnmt3a and mbd3 mRNAs in the tadpole brain, and we investigated their regional expression. Dnmt3a mRNA is widely expressed throughout the tadpole brain in regions where cells are undergoing migration and differentiation, but is excluded from the ventricular and subventricular zones (VZ/SVZ) where cell proliferation occurs. By contrast, the expression of mbd3 mRNA is restricted to the periphery of the VZ/SVZ throughout the tadpole brain. Our findings support that T3 may control neurogenesis through regulation of expression of DNMTs and MBDs. Acknowledgements Supported by NSF grants IBN 0235401 and IOS 0922583 to RJD Keywords: Brain, DNA Methylation, epigenetics, metamorphosis, Thyroid hormone Conference: NASCE 2011: The inaugural meeting of the North American Society for Comparative Endocrinology, Ann Arbor, United States, 13 Jul - 16 Jul, 2011. Presentation Type: Poster Topic: Developmental endocrinology Citation: Kyono Y and Denver RJ (2011). DEVELOPMENTAL AND THYROID HORMONE-INDUCED EXPRESSION OF DNA METHYLTRANSFERASES AND METHYL-CPG BINDING PROTEINS IN XENOPUS TADPOLE BRAIN DURING METAMORPHOSIS. Front. Endocrinol. Conference Abstract: NASCE 2011: The inaugural meeting of the North American Society for Comparative Endocrinology. doi: 10.3389/conf.fendo.2011.04.00028 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: 18 Jul 2011; Published Online: 09 Aug 2011. * Correspondence: Prof. Robert J Denver, University of Michigan, Molecular, Cellular and Developmental Biology, Ann Arbor, United States, Rdenver@umich.edu 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 Yasuhiro Kyono Robert J Denver Google Yasuhiro Kyono Robert J Denver Google Scholar Yasuhiro Kyono Robert J Denver PubMed Yasuhiro Kyono Robert J Denver 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.