Intrafollicular Communication Network in the Zebrafish Ovary – What Have We Learnt from the Zebrafish Model?

Abstract

Event Abstract Back to Event Intrafollicular Communication Network in the Zebrafish Ovary – What Have We Learnt from the Zebrafish Model? Wei Ge1* 1 The Chinese University of Hong Kong, Cell and Molecular Biology Programme, School of Life Sciences, China In the ovary there exists an intrinsic communication network within the follicle consisting of various growth factors. In the zebrafish, we have characterized several important growth factor families within the follicle, including epidermal growth factor (EGF), activin-inhibin-follistatin, Kit/Kit ligand, and GDF9/BMP families. These factors are likely involved in bidirectional communication between the oocyte and follicle cells. As a potential mediator of gonadotropin actions, activin subunits (inhbaa and inhbb) are exclusively expressed in the follicle cells whereas its receptors are abundantly expressed in the oocyte. In contrast, EGF and BMP families are mostly expressed in the oocyte, but their receptors (EGFR and BMPRII) are exclusively located in the follicle cells. The Kit/Kit ligand system is unique in that the system consists of two ligands (kitlga and kitlgb) and two receptors (kita and kitb). The distribution of Kits/Kit ligands in the follicle and the evidence for receptor specificity suggest that Kitlga-Kita and Kitlgb-Kitb may represent two paracrine regulatory pathways within the follicle that mediate reciprocal communications between the two compartments. Our functional studies have demonstrated extensive interactions among these signaling pathways in the follicle. We have recently characterized inhibin, a natural activin antagonist, in the zebrafish ovary. Similar to activin subunits, inhibin alpha subunit (inha) is exclusively expressed in the follicle cells and its expression level surges at the full-grown stage prior to oocyte maturation, which has led us to hypothesize that the preovulatory surge of inhibin production may serve as an ovarian messenger to signal the pituitary for final maturation, and inhibin may act by antagonizing the effects of activin on FSH and LH biosynthesis in the pituitary. The expression of inha is likely subject to the regulation by oocyte-derived factors such as BMPs. Acknowledgements The work was substantially supported by grants (CUHK457805, 458706, 464707, 464308 and 464409) from the Research Grants Council of the Hong Kong Special Administrative Region to W. Ge. Keywords: activin, BMP, EGF, Follistatin, inhibin, Ovary, Zebrafish 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: Invited Symposium Topic: Gonadal development and gamete maturation Citation: Ge W (2011). Intrafollicular Communication Network in the Zebrafish Ovary – What Have We Learnt from the Zebrafish Model?. Front. Endocrinol. Conference Abstract: NASCE 2011: The inaugural meeting of the North American Society for Comparative Endocrinology. doi: 10.3389/conf.fendo.2011.04.00134 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: 23 Jul 2011; Published Online: 09 Aug 2011. * Correspondence: Prof. Wei Ge, The Chinese University of Hong Kong, Cell and Molecular Biology Programme, School of Life Sciences, Hong Kong, China, weige@um.edu.mo 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 Wei Ge Google Wei Ge Google Scholar Wei Ge PubMed Wei Ge 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.