Publication
Title
Adipokinetic hormone signaling through the gonadotropin-releasing hormone receptor modulates egg-laying in **Caenorhabditis elegans**
Author
Abstract
In mammals, hypothalamic gonadotropin-releasing hormone (GnRH) is a neuropeptide that stimulates the release of gonadotropins from the anterior pituitary. The existence of a putative functional equivalent of this reproduction axis in protostomian invertebrates has been a matter of debate. In this study, the ligand for the GnRH receptor in the nematode Caenorhabditis elegans (Ce-GnRHR) was found using a bioinformatics approach. The peptide and its precursor are reminiscent of both insect adipokinetic hormones and GnRH-preprohormone precursors from tunicates and higher vertebrates. We cloned the AKH-GnRH-like preprohormone and the Ce-GnRHR and expressed the GPCR in HEK293T cells. The GnRHR was activated by the C. elegans AKH-GnRH-like peptide (EC(50) = 150 nM) and by Drosophila AKH and other nematode AKH-GnRHs that we found in EST databases. Analogous to both insect AKH receptor and vertebrate GnRH receptor signaling, Ce-AKH-GnRH activated its receptor through a G alpha(q) protein with Ca(2+) as a second messenger. Gene silencing of Ce-GnRHR, Ce-AKH-GnRH, or both resulted in a delay in the egg-laying process, comparable to a delay in puberty in mammals lacking a normal dose of GnRH peptide or with a mutated GnRH precursor or receptor gene. The present data support the view that the AKH-GnRH signaling system probably arose very early in metazoan evolution and that its role in reproduction might have been developed before the divergence of protostomians and deuterostomians.
Language
English
Source (journal)
Proceedings of the National Academy of Sciences of the United States of America. - Washington, D.C.
Publication
Washington, D.C. : 2009
ISSN
0027-8424 [Print]
1091-6490 [Online]
Volume/pages
106:5(2009), p. 1642-1647
ISI
000263074600063
Full text (Publishers DOI)
Full text (publishers version - intranet only)
UAntwerpen
Faculty/Department
Publication type
Subject
External links
Web of Science
Record
Identification
Creation 11.03.2013
Last edited 20.05.2017