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Title: FMRF‐NH2‐related neuropeptides in Biomphalaria spp., intermediate hosts for schistosomiasis: Precursor organization and immunohistochemical localization
Abstract

Freshwater snails of the genusBiomphalariaserve as intermediate hosts for the digenetic trematodeSchistosoma mansoni, the etiological agent for the most widespread form of intestinal schistosomiasis. As neuropeptide signaling in host snails can be altered by trematode infection, a neural transcriptomics approach was undertaken to identify peptide precursors inBiomphalaria glabrata, the major intermediate host forS.mansoniin the Western Hemisphere. Three transcripts that encode peptides belonging to the FMRF‐NH2‐related peptide (FaRP) family were identified inB.glabrata. One transcript encoded a precursor polypeptide (Bgl‐FaRP1; 292 amino acids) that included eight copies of the tetrapeptide FMRF‐NH2and single copies of FIRF‐NH2, FLRF‐NH2, and pQFYRI‐NH2. The second transcript encoded a precursor (Bgl‐FaRP2;347amino acids) that comprised 14 copies of the heptapeptide GDPFLRF‐NH2and 1 copy of SKPYMRF‐NH2. The precursor encoded by the third transcript (Bgl‐FaRP3; 287 amino acids) recapitulatedBgl‐FaRP2but lacked the full SKPYMRF‐NH2peptide. The three precursors shared a common signal peptide, suggesting a genomic organization described previously in gastropods. Immunohistochemical studies were performed on the nervous systems ofB.glabrataandB.alexandrina, a major intermediate host forS.mansoniin Egypt. FMRF‐NH2‐like immunoreactive (FMRF‐NH2‐li) neurons were located in regions of the central nervous system associated with reproduction, feeding, and cardiorespiration. Antisera raised against non‐FMRF‐NH2peptides present in the tetrapeptide and heptapeptide precursors labeled independent subsets of the FMRF‐NH2‐li neurons. This study supports the participation of FMRF‐NH2‐related neuropeptides in the regulation of vital physiological and behavioral systems that are altered by parasitism inBiomphalaria.

 
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Award ID(s):
1545803 1736019
NSF-PAR ID:
10449501
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Journal of Comparative Neurology
Volume:
529
Issue:
13
ISSN:
0021-9967
Page Range / eLocation ID:
p. 3336-3358
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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