FN Archimer Export Format PT J TI Gonadal transcriptomes associated with sex phenotypes provide potential male and female candidate genes of sex determination or early differentiation in Crassostrea gigas, a sequential hermaphrodite mollusc BT AF Broquard, Coralie Saowaros, Suwansa-ard Lepoittevin, Mélanie Degremont, Lionel Lamy, Jean-Baptiste Morga, Benjamin Elizur, Abigail Martinez, Anne-Sophie AS 1:1,2,3;2:4,5;3:1,2;4:3;5:3;6:3;7:;8:1,2,5; FF 1:;2:;3:;4:PDG-RBE-SGMM-LGPMM;5:PDG-RBE-SGMM-LGPMM;6:PDG-RBE-SGMM-LGPMM;7:;8:; C1 Normandie University, UNICAEN, CNRS, BOREA, 14000, Caen, France Laboratoire de Biologie des Organismes et Ecosystèmes Aquatiques (BOREA), Université de Caen Normandie, MNHN, SU, UA, CNRS, IRD, Esplanade de la Paix, CS 14032, 14032, Cedex 05, Caen, France Ifremer, RBE-SG2M-LGPMM, La Tremblade, France Department of Anatomy, Faculty of Science, Mahidol University, Bangkok, Thailand Genecology Research Centre, University of the Sunshine Coast, Sippy Downs, Queensland, Australia C2 UNIV NORMANDIE, FRANCE UNIV CAEN NORMANDIE, FRANCE IFREMER, FRANCE UNIV MAHIDOL, THAILAND UNIV SUNSHINE COAST, AUSTRALIA SI LA TREMBLADE SE PDG-RBE-SGMM-LGPMM IN WOS Ifremer UPR DOAJ copubli-france copubli-univ-france copubli-int-hors-europe copubli-sud IF 4.558 TC 12 UR https://archimer.ifremer.fr/doc/00718/83026/87929.pdf https://archimer.ifremer.fr/doc/00718/83026/87930.xlsx https://archimer.ifremer.fr/doc/00718/83026/87931.pdf https://archimer.ifremer.fr/doc/00718/83026/87932.xlsx LA English DT Article DE ;RNA-Seq;Gonad transcriptome;Early sex differentiation;Sex determination;Irregular hermaphrodite;Oyster AB Background In the animal kingdom, mollusca is an important phylum of the Lophotrochozoa. However, few studies have investigated the molecular cascade of sex determination/early gonadal differentiation within this phylum. The oyster Crassostrea gigas is a sequential irregular hermaphrodite mollusc of economic, physiological and phylogenetic importance. Although some studies identified genes of its sex-determining/−differentiating pathway, this particular topic remains to be further deepened, in particular with regard to the expression patterns. Indeed, these patterns need to cover the entire period of sex lability and have to be associated to future sex phenotypes, usually impossible to establish in this sequential hermaphrodite. This is why we performed a gonadal RNA-Seq analysis of diploid male and female oysters that have not changed sex for 4 years, sampled during the entire time-window of sex determination/early sex differentiation (stages 0 and 3 of the gametogenetic cycle). This individual long-term monitoring gave us the opportunity to explain the molecular expression patterns in the light of the most statistically likely future sex of each oyster. Results The differential gene expression analysis of gonadal transcriptomes revealed that 9723 genes were differentially expressed between gametogenetic stages, and 141 between sexes (98 and 43 genes highly expressed in females and males, respectively). Eighty-four genes were both stage- and sex-specific, 57 of them being highly expressed at the time of sex determination/early sex differentiation. These 4 novel genes including Trophoblast glycoprotein-like, Protein PML-like, Protein singed-like and PREDICTED: paramyosin, while being supported by RT-qPCR, displayed sexually dimorphic gene expression patterns. Conclusions This gonadal transcriptome analysis, the first one associated with sex phenotypes in C. gigas, revealed 57 genes highly expressed in stage 0 or 3 of gametogenesis and which could be linked to the future sex of the individuals. While further study will be needed to suggest a role for these factors, some could certainly be original potential actors involved in sex determination/early sex differentiation, like paramyosin and could be used to predict the future sex of oysters. PY 2021 PD AUG SO Bmc Genomics SN 1471-2164 PU Springer Science and Business Media LLC VL 22 IS 1 UT 000685089900006 DI 10.1186/s12864-021-07838-1 ID 83026 ER EF