FN Archimer Export Format PT J TI Transcriptomic Adjustments in a Freshwater Ectoparasite Reveal the Role of Molecular Plasticity for Parasite Host Shift BT AF Mathieu-Bégné, Eglantine Blanchet, Simon Mitta, Guillaume Le Potier, Clément Loot, Géraldine Rey, Olivier AS 1:1,2,3;2:1,2;3:4;4:1;5:1,5;6:3; FF 1:;2:;3:PDG-RBE-RMPF;4:;5:;6:; C1 Laboratoire Evolution et Diversité Biologique (UMR5174), Institut de Recherche pour le Développement, Centre National pour la Recherche Scientifique, Université Paul Sabatier, 118 Route de Narbonne, F-31062 Toulouse, France Station d’Ecologie Théorique et Expérimentale (UPR 2001), Centre National pour la Recherche Scientifique, 2 Route du CNRS, F-09200 Moulis, France Interactions Hôtes-Pathogènes-Environnement (UMR5244 IHPE), CNRS, Université de Montpellier, Ifremer, Université de Perpignan Via Domitia, F-66000 Perpignan, France UMR EIO, ILM, IRD, Ifremer, University Polynesie Francaise, Taravao F-98719, Tahiti, French Polynesia Institut Universitaire de France, Université Paul Sabatier, CEDEX 05, F-75231 Paris, France C2 IRD, FRANCE CNRS, FRANCE UNIV MONTPELLIER, FRANCE IFREMER, FRANCE INST UNIV FRANCE, FRANCE SI TAHITI SE PDG-RBE-RMPF UM IHPE EIO IN WOS Ifremer UMR WOS Cotutelle UMR DOAJ copubli-france copubli-p187 copubli-univ-france IF 3.5 TC 1 UR https://archimer.ifremer.fr/doc/00756/86849/92339.pdf https://archimer.ifremer.fr/doc/00756/86849/92340.zip LA English DT Article DE ;plasticity;gene expression;host shift;parasite specificity;emerging parasites;rapid adaptation AB A parasite’s lifestyle is characterized by a critical dependency on its host for feeding, shelter and/or reproduction. The ability of parasites to exploit new host species can reduce the risk associated with host dependency. The number of host species that can be infected by parasites strongly affects their ecological and evolutionary dynamics along with their pathogenic effects on host communities. However, little is known about the processes and the pathways permitting parasites to successfully infect alternative host species, a process known as host shift. Here, we tested whether molecular plasticity changes in gene expression and in molecular pathways could favor host shift in parasites. Focusing on an invasive parasite, Tracheliastes polycolpus, infecting freshwater fish, we conducted a transcriptomic study to compare gene expression in parasites infecting their main host species and two alternative host species. We found 120 significant differentially expressed genes (DEGs) between parasites infecting the different host species. A total of 90% of the DEGs were identified between parasites using the main host species and those using the two alternative host species. Only a few significant DEGs (seven) were identified when comparing parasites from the two alternative host species. Molecular pathways enriched in DEGs and associated with the use of alternative host species were related to cellular machinery, energetic metabolism, muscle activity and oxidative stress. This study strongly suggests that molecular plasticity is an important mechanism sustaining the parasite’s ability to infect alternative hosts. PY 2022 PD MAR SO Genes SN 2073-4425 PU MDPI AG VL 13 IS 3 UT 000775379600001 DI 10.3390/genes13030525 ID 86849 ER EF