ANNOTATION OF THE NEUROENDOCRINE-ASSOCIATED GENES OF THE LAMPREY PETROMYZON MARINUS AND THE IMPLICATIONS FOR EVOLUTION OF VERTEBRATE GONADOTROPIN-RELEASING HORMONES
-
1
University of New Hampshire, Center for Molecular and Comparative Endocrinology, United States
-
2
University of Kentucky, Department of Biology, United States
-
3
Michigan State University, Department of Fisheries and Wildlife, United States
The development of the hypothalamic-pituitary axis was a seminal event in the evolution of vertebrates. Study of the ancestral jawless vertebrates is key to understanding this event, with the gonadotropin-releasing hormones (GnRHs) deserving particular attention given their pivotal placement in the hierarchy of the neuroendocrine system. Previous data incorporating several lines of evidence showed all known vertebrate GnRHs were grouped into four paralogous lineages: GnRH 1, 2, 3 and 4; with proposed evolutionary paths. Using the currently available lamprey genome assembly, we have identified many neuroendocrine system genes and analyzed in greater detail the evolutionary history of the GnRHs based on the conserved syntenies between lamprey and gnathostomes. Our analysis corroborates recent views that GnRH3 was lost in the tetrapod lineage and did not arise in the teleost lineage as a result of a third round of whole genome duplication. With respect to the agnathans and GnRH, our analysis of the synteny agree with the previous proposal in that lamprey GnRH-I and –III resulted from a duplication event within the lamprey lineage. However, the data now suggest a substantially different view of the evolutionary history of the GnRH family in vertebrates. Significantly, the current evidence suggests that all of the genome duplication events that generated the different fish and tetrapod paralogous groups likely took place before the divergence of the ancestral agnathans and gnathostome lineages and that the type IV GnRHs in lamprey (GnRH-I and -III) share a more recent common ancestry with GnRH2 and 3. Given the single amino acid difference between lamprey GnRH-II and GnRH2 we propose that a GnRH2-like gene existed before the lamprey/gnathostome split and that paralogous genes (GnRH-I/III and GnRH 3) evolved divergent structure/function in lamprey and gnathostome lineages. The synteny analysis offers a new view on the evolution of the GnRHs.
Acknowledgements
Supported by NSF IOS-0849569, NH AES Hatch 332 and the Lamprey Genome Project Consortium.
Keywords:
evolution,
Genome,
GnRH,
Lamprey,
neuroendocrine,
Synteny
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:
Molecular evolution
Citation:
Decatur
WA,
Smith
JJ,
Hall
J,
Li
W and
Sower
SA
(2011). ANNOTATION OF THE NEUROENDOCRINE-ASSOCIATED GENES OF THE LAMPREY PETROMYZON MARINUS AND THE IMPLICATIONS FOR EVOLUTION OF VERTEBRATE GONADOTROPIN-RELEASING HORMONES.
Front. Endocrinol.
Conference Abstract:
NASCE 2011: The inaugural meeting of the North American Society for Comparative Endocrinology.
doi: 10.3389/conf.fendo.2011.04.00124
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:
22 Jul 2011;
Published Online:
09 Aug 2011.
*
Correspondence:
Dr. Stacia A Sower, University of New Hampshire, Center for Molecular and Comparative Endocrinology, Durham, NH, 03824, United States, sasower@cisunix.unh.edu