IDENTIFICATION OF GENDER-SPECIFIC TRANSCRIPTS BY MICROARRAY IN GONAD TISSUE OF LARVAL AND JUVENILE XENOPUS TROPICALIS

Abstract

Event Abstract Back to Event IDENTIFICATION OF GENDER-SPECIFIC TRANSCRIPTS BY MICROARRAY IN GONAD TISSUE OF LARVAL AND JUVENILE XENOPUS TROPICALIS Jonathan T. Haselman1*, Allen W. Olmstead1 and Sigmund J. Degitz1 1 US Environmental Protection Agency, Mid-Continent Ecology Division, United States Amphibian model species Xenopus tropicalis is currently being utilized by EPA in the development of a standardized in vivo reproductive toxicity assay. Perturbations to the hypothalamic-pituitary-gonadal axis from exposure to endocrine disrupting compounds during larval development have been shown to induce abnormal gonad differentiation resulting in either functional sex-reversal or intersex conditions. In an effort to develop a gene expression-based diagnostic tool we characterized male and female gonadal transcriptomes by microarray. Gonad tissues were harvested from Nieuwkoop and Faber (NF) stage 58 larvae, NF 66 froglets, one week and two week old juveniles. Individual animals were genotyped to confirm genetic sex and gonad RNA was extracted and pooled according to developmental stage and gender. Initial data analyses were performed with Agilent GeneSpring GX 11 and gene enrichment and ontology analyses were carried out with gender-specific gene lists using DAVID Bioinformatics Resources 6.7. Results confirm significant differences (p≤ 0.05 and differential expression ≥ 10-fold) in expression in two week old juveniles between ovary and testis tissues of several enzymes involved in steroid hormone biosynthesis. Other ovary-specific profiles include oocyte-specific proteins and several proteins involved in progesterone mediated oocyte maturation and oocyte meiosis. Additional testis-specific profiles include a Leydig cell-specific peptide and hormone receptors. These data allow for further investigation of molecular interactions responsible for gonad differentiation and will provide candidate genes for use as expression-based biomarkers of gonad maturation. Examination of these expression profiles in gonad tissue influenced by xenobiotic exposure will provide insight into molecular mechanisms and processes leading to amphibian gonadal intersex and functional sex-reversal. This abstract does not necessarily reflect U.S. EPA policy. Acknowledgements The authors would like to thank Hongzu Ren from the Genomics Research Core of US EPA for preparing and analyzing the Affymetrix array chips. The authors would also like to thank Chad Blanksma for the gonad histology processing and images. References Nieuwkoop, P. and Faber, J. (1967). Normal Table of Xenopus laevis. Daudin, North-Holland, Amsterdam Huang DW, Sherman BT, Lempicki RA. Systematic and integrative analysis of large gene lists using DAVID Bioinformatics Resources. Nature Protoc. 2009;4(1):44-57. Huang DW, Sherman BT, Lempicki RA. Bioinformatics enrichment tools: paths toward the comprehensive functional analysis of large gene lists. Nucleic Acids Res. 2009;37(1):1-13. Olmstead AW, Lindberg-Livingston A, Degitz SJ. Genotyping sex in the amphibian, Xenopus (Silurana) tropicalis, for endocrine disruptor bioassays. Aquatic Toxicology. 2010;98(1):60-66. Keywords: Gonad differentiation, Intersex, Microarray, Sex reversal, Xenopus tropicalis Conference: ISAREN 2011: 7th International Symposium on Amphibian and Reptilian Endocrinology and Neurobiology, Ann Arbor, United States, 11 Jul - 13 Jul, 2011. Presentation Type: Poster Topic: Sex determination and differentiation Citation: Haselman JT, Olmstead AW and Degitz SJ (2011). IDENTIFICATION OF GENDER-SPECIFIC TRANSCRIPTS BY MICROARRAY IN GONAD TISSUE OF LARVAL AND JUVENILE XENOPUS TROPICALIS. Front. Endocrinol. Conference Abstract: ISAREN 2011: 7th International Symposium on Amphibian and Reptilian Endocrinology and Neurobiology. doi: 10.3389/conf.fendo.2011.03.00016 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: 08 Jul 2011; Published Online: 09 Aug 2011. * Correspondence: Mr. Jonathan T Haselman, US Environmental Protection Agency, Mid-Continent Ecology Division, Duluth, MN, 55804, United States, haselman.jon@epa.gov Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract Supplemental Data The Authors in Frontiers Jonathan T Haselman Allen W Olmstead Sigmund J Degitz Google Jonathan T Haselman Allen W Olmstead Sigmund J Degitz Google Scholar Jonathan T Haselman Allen W Olmstead Sigmund J Degitz PubMed Jonathan T Haselman Allen W Olmstead Sigmund J Degitz 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.