@article {7996, title = {Molecular and physiological characterization of a crustacean cardioactive signaling system in a lophotrochozoan - the Pacific oyster (Crassostrea gigas): a role in reproduction and salinity acclimation.}, journal = {J Exp Biol}, volume = {224}, year = {2021}, month = {2021 May 15}, abstract = {

The crustacean cardioactive peptide (CCAP) is an important neuropeptide involved in the regulation of a variety of physiological processes in arthropods. Although this family of peptides has an ancestral origin, its function remains poorly understood among protostome species - apart from arthropods. We functionally characterized three G protein-coupled receptors (GPCRs) in the oyster Crassostrea gigas, phylogenetically related to ecdysozoan CCAP receptors (CCAPRs) and to chordate neuropeptide S receptors (NPSRs). Cragi-CCAPR1 and Cragi-CCAPR2 were specifically activated by the Cragi-CCAP1 and Cragi-CCAP2 peptides, respectively, both derived from the same CCAP precursor. In contrast, Cragi-CCAPR3 was only partially activated by CCAP1 and CCAP2 at high concentrations. The Cragi-CCAPR1 and Cragi-CCAPR2 genes were expressed in various adult tissues. They are both most expressed in the gills, while Cragi-CCAPR3 is mainly expressed in the visceral ganglia (VG). Cragi-CCAP precursor transcripts are higher in the VG, the labial palps and the gills. Receptor and ligand-encoding transcripts are more abundantly expressed in the gonads in the first stages of gametogenesis, while the Cragi-CCAP precursor is upregulated in the VG in the last stages of gametogenesis. This suggests a role of the CCAP signaling system in the regulation of reproductive processes. A role in water and ionic regulation is also supported considering the differential expression of the CCAP signaling components in oysters exposed to brackish water.

}, issn = {1477-9145}, doi = {10.1242/jeb.241588}, author = {R{\'e}alis-Doyelle, Emilie and Julie Schwartz and Marie-Pierre Dubos and Pascal Favrel} } @article {8117, title = {A Novel Dop2/Invertebrate-Type Dopamine Signaling System Potentially Mediates Stress, Female Reproduction, and Early Development in the Pacific Oyster (Crassostrea gigas)}, journal = {Marine Biotechnology}, year = {2021}, month = {Jul-08-2021}, issn = {1436-2228}, doi = {10.1007/s10126-021-10052-5}, url = {https://link.springer.com/10.1007/s10126-021-10052-5}, author = {Schwartz, Julie and R{\'e}alis-Doyelle, Emilie and Le Franc, Lorane and Favrel, Pascal} } @article {9561, title = {Transcriptome Profiling of the Pacific Oyster Crassostrea gigas Visceral Ganglia over a Reproduction Cycle Identifies Novel Regulatory Peptides}, journal = {Marine Drugs}, volume = {19}, year = {2021}, month = {Jan-08-2021}, pages = {452}, doi = {10.3390/md19080452}, url = {https://www.mdpi.com/1660-3397/19/8/452}, author = {R{\'e}alis-Doyelle, Emilie and Schwartz, Julie and Cabau, C{\'e}dric and Le Franc, Lorane and Bernay, Beno{\^\i}t and Guillaume Rivi{\`e}re and Klopp, Christophe and Favrel, Pascal} } @article {8123, title = {Transcriptome Profiling of the Pacific Oyster Visceral Ganglia over a Reproduction Cycle Identifies Novel Regulatory Peptides.}, journal = {Mar Drugs}, volume = {19}, year = {2021}, month = {2021 Aug 07}, abstract = {

The neuropeptides involved in the regulation of reproduction in the Pacific oyster () are quite diverse. To investigate this diversity, a transcriptomic survey of the visceral ganglia (VG) was carried out over an annual reproductive cycle. RNA-seq data from 26 samples corresponding to VG at different stages of reproduction were de novo assembled to generate a specific reference transcriptome of the oyster nervous system and used to identify differentially expressed transcripts. Transcriptome mining led to the identification of novel neuropeptide precursors (NPPs) related to the bilaterian Eclosion Hormone (EH), crustacean female sex hormone/Interleukin 17, Nesfatin, neuroparsin/IGFBP, prokineticins, and urotensin I; to the protostome GNQQN, pleurin, prohormones 3 and 4, prothoracotropic hormones (PTTH), and QSamide/PXXXamide; to the lophotrochozoan CCWamide, CLCCY, HFAamide, and LXRX; and to the mollusk-specific NPPs CCCGS, clionin, FYFY, GNamide, GRWRN, GSWN, GWE, IWMPxxGYxx, LXRYamide, RTLFamide, SLRFamide, and WGAGamide. Among the complete repertoire of NPPs, no sex-biased expression was observed. However, 25 NPPs displayed reproduction stage-specific expression, supporting their involvement in the control of gametogenesis or associated metabolisms.

}, issn = {1660-3397}, doi = {10.3390/md19080452}, author = {R{\'e}alis-Doyelle, Emilie and Schwartz, Julie and Cabau, C{\'e}dric and Le Franc, Lorane and Bernay, Beno{\^\i}t and Riviere, Guillaume and Klopp, Christophe and Favrel, Pascal} } @article {6796, title = {Characterization of an evolutionarily conserved calcitonin signalling system in a lophotrochozoan, the Pacific oyster (Crassostrea gigas) }, journal = {The Journal of Experimental Biology}, volume = {222}, year = {2019}, month = {Jan-07-2019}, pages = {jeb201319}, issn = {0022-0949}, doi = {10.1242/jeb.201319}, url = {http://jeb.biologists.org/lookup/doi/10.1242/jeb.201319}, author = {Julie Schwartz and R{\'e}alis-Doyelle, Emilie and Marie-Pierre Dubos and Lefranc, Benjamin and Leprince, J{\'e}r{\^o}me and Pascal Favrel} } @article {6116, title = {Characterization of an evolutionarily conserved calcitonin signalling system in a lophotrochozoan, the Pacific oyster ().}, journal = {J Exp Biol}, volume = {222}, year = {2019}, month = {2019 Jul 05}, abstract = {

In Protostoma, the diuretic hormone 31 (DH31) signalling system was long considered as the orthologue of the chordate calcitonin (CT) signalling system. Using the Pacific oyster () transcriptomic database GigaTON, we characterized seven G-protein-coupled receptors (GPCRs) named Cragi-CTR1-7 and phylogenetically related to chordate CT receptors (CTRs) and to protostome DH31 receptors. Two CT precursors (Cragi-CTP1 and Cragi-CTP2) containing two CT-type peptides and encoded by two distinct genes with a similar organization were also characterized. These oyster neuropeptides (Cragi-CT1/2) exhibit the two N-terminal paired cysteine residues and, except CTP2-derived peptide (Cragi-CTP2dp), show the C-terminal proline-amide motif typical of deuterostome CT-type peptides. All mature Cragi-CTs except Cragi-CTP2dp were detected in visceral ganglion extracts using mass spectrometry. Cell-based assays revealed that the previously characterized oyster receptors Cg-CT-R and Cragi-CTR2 were specifically activated by Cragi-CT1b and Cragi-CT2, respectively. This activation does not require the co-expression of receptor activity-modifying proteins (RAMPs). Thus, oyster CT signalling appears functionally more closely related to vertebrate CT/CTR signalling than to calcitonin gene-related peptide/calcitonin receptor-like receptor (CGRP/CLR) signalling. Gene expression profiles in different adult tissues and in oysters acclimated to brackish water suggest the potential implication of both Cg-CT-R/Cragi-CT1b and Cragi-CTR2/Cragi-CT2 in water and ionic regulations, although with apparently opposite effects. The present study represents the first comprehensive characterization of a functional CT-type signalling system in a protostome and provides evidence for its evolutionarily ancient origin and its early role in osmotic homeostasis.

}, issn = {1477-9145}, doi = {10.1242/jeb.201319}, author = {Julie Schwartz and R{\'e}alis-Doyelle, Emilie and Marie-Pierre Dubos and Lefranc, Benjamin and Leprince, J{\'e}r{\^o}me and Pascal Favrel} }