This article is part of the Research Topic Neuropeptide GPCRs in neuroendocrinology

Mini Review ARTICLE

Front. Endocrinol., 19 November 2012 | http://dx.doi.org/10.3389/fendo.2012.00140

Evolution of vertebrate GnRH receptors from the perspective of a basal vertebrate

  • Department of Molecular, Cellular and Biomedical Sciences, Center for Molecular and Comparative Endocrinology, University of New Hampshire, Durham, NH, USA

This minireview provides the current status on gonadotropin-releasing hormone receptors (GnRH-R) in vertebrates, from the perspective of a basal vertebrate, the sea lamprey, and provides an evolutionary scheme based on the recent advance of whole genome sequencing. In addition, we provide a perspective on the functional divergence and evolution of the receptors. In this review we use the phylogenetic classification of vertebrate GnRH receptors that groups them into three clusters: type I (mammalian and non-mammalian), type II, and type III GnRH receptors. New findings show that the sea lamprey has two type III-like GnRH receptors and an ancestral type GnRH receptor that is more closely related to the type II-like receptors. These two novel GnRH receptors along with lGnRH-R-1 share similar structural features and amino acid motifs common to other known gnathostome type II/III receptors. Recent data analyses of the lamprey genome provide strong evidence that two whole rounds of genome duplication (2R) occurred prior to the gnathostome-agnathan split. Based on our current knowledge, it is proposed that lGnRH-R-1 evolved from an ancestor of the type II receptor following a vertebrate-shared genome duplication and that the two type III receptors resulted from a duplication within lamprey of a gene derived from a lineage shared by many vertebrates.

Keywords: gonadotropin-releasing hormone receptors, G protein-coupled receptors, evolution, lamprey, basal vertebrate, receptor, hormone, pituitary

Citation: Sower SA, Decatur WA, Joseph NT and Freamat M (2012) Evolution of vertebrate GnRH receptors from the perspective of a basal vertebrate. Front. Endocrin. 3:140. doi: 10.3389/fendo.2012.00140

Received: 30 August 2012; Paper pending published: 24 September 2012;
Accepted: 26 October 2012; Published online: 19 November 2012.

Edited by:

Hubert Vaudry, University of Rouen, France

Reviewed by:

Olivier Kah, CNRS UMR 6026, France
Jae Young Seong, Korea University, Korea

Copyright: © 2012 Sower, Decatur, Joseph and Freamat. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in other forums, provided the original authors and source are credited and subject to any copyright notices concerning any third-party graphics etc.

*Correspondence: Stacia A. Sower, Department of Molecular, Cellular and Biomedical Sciences, Center for Molecular and Comparative Endocrinology, University of New Hampshire, 46 College Road, Durham, NH 03824-3544, USA. e-mail: sasower@unh.edu