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Title: Identification and localization of a gonadotropin‐releasing hormone‐related neuropeptide in Biomphalaria , an intermediate host for schistosomiasis
Abstract

Freshwater snails of the genusBiomphalariaserve as obligatory hosts for the digenetic trematodeSchistosoma mansoni, the causative agent for the most widespread form of intestinal schistosomiasis. WithinBiomphalaria,S.mansonilarvae multiply and transform into the cercariae form that can infect humans. Trematode development and proliferation is thought to be facilitated by modifications of host behavior and physiological processes, including a reduction of reproduction known as “parasitic castration.” As neuropeptides participate in the control of reproduction across phylogeny, a neural transcriptomics approach was undertaken to identify peptides that could regulateBiomphalariareproductive physiology. The present study identified a transcript inBiomphalaria alexandrinathat encodes a peptide belonging to the gonadotropin‐releasing hormone (GnRH) superfamily. The precursor and the predicted mature peptide, pQIHFTPDWGNN‐NH2(designatedBiom‐GnRH), share features with peptides identified in other molluscan species, including panpulmonates, opisthobranchs, and cephalopods. An antibody generated againstBiom‐GnRH labeled neurons in the cerebral, pedal, and visceral ganglia ofBiomphalaria glabrata. GnRH‐like immunoreactive fiber systems projected to all central ganglia. In the periphery, immunoreactive material was detected in the ovotestis, oviduct, albumen gland, and nidamental gland. As these structures serve crucial roles in the production, transport, nourishment, and encapsulation of eggs, disruption of the GnRH system ofBiomphalariacould contribute to reduced reproductive activity in infected snails.

 
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NSF-PAR ID:
10453879
Author(s) / Creator(s):
 ;  ; ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Journal of Comparative Neurology
Volume:
529
Issue:
9
ISSN:
0021-9967
Page Range / eLocation ID:
p. 2347-2361
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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