Dengue virus harnesses mosquito Syntenin to load and secrete viral RNA into salivary exosomes

F Florian Rachenne (Maladies Infectieuses et Vecteurs: Ecologie, Génétique, Evolution et Controle, University of Montpellier, Institut of Research for development, CNRS) N Norman Schneider (Maladies Infectieuses et Vecteurs: Ecologie, Génétique, Evolution et Controle, University of Montpellier, Institut of Research for development, CNRS) F Félix Rey-Cadilhac (Maladies Infectieuses et Vecteurs: Ecologie, Génétique, Evolution et Controle, University of Montpellier, Institut of Research for development, CNRS) I Idalba Serrato-Pomar (Maladies Infectieuses et Vecteurs: Ecologie, Génétique, Evolution et Controle, University of Montpellier, Institut of Research for development, CNRS) L Lauryne Pruvost (Maladies Infectieuses et Vecteurs: Ecologie, Génétique, Evolution et Controle, University of Montpellier, Institut of Research for development, CNRS) L Laura Di Pietro (Maladies Infectieuses et Vecteurs: Ecologie, Génétique, Evolution et Controle, University of Montpellier, Institut of Research for development, CNRS) J Jacques Dainat (Maladies Infectieuses et Vecteurs: Ecologie, Génétique, Evolution et Controle, University of Montpellier, Institut of Research for development, CNRS) A Audrey Vernet (Plant Health Institute of Montpellier, University of Montpellier, Institut of Research for development) C Chantal Cazevieille (Université Montpellier, INSERM U1298, Institute for Neurosciences of Montpellier) A Aurélie Ancelin (Centre de Biologie Structurale, Electronic Microscopy Platform, CNRS) J Joséphine Lai Kee Him (Centre de Biologie Structurale, Electronic Microscopy Platform, CNRS) S Sander Jansen (Katholic University Leuven, Department of Microbiology, Immunology and Transplantion, Rega Institute, Laboratory of Molecular Vaccinology and Vaccine Discovery) E Elliott F. Miot (Maladies Infectieuses et Vecteurs: Ecologie, Génétique, Evolution et Controle, University of Montpellier, Institut of Research for development, CNRS) J Jérémy Fraering (Plateforme Protéomique Strasbourg-Esplanade, CNRS UAR1589, Institut de Biologie Moléculaire et Cellulaire, Université de Strasbourg) L Laurianne Simon (Institut Charles Gerhardt Montpellier, University of Montpellier, CNRS, Ecole Nationale Supérieure de Chimie de Montpellier) D Dorothée Missé (Maladies Infectieuses et Vecteurs: Ecologie, Génétique, Evolution et Controle, University of Montpellier, Institut of Research for development, CNRS) M Marie Morille (Institut Charles Gerhardt Montpellier, University of Montpellier, CNRS, Ecole Nationale Supérieure de Chimie de Montpellier) P Philippe Hammann (Plateforme Protéomique Strasbourg-Esplanade, CNRS UAR1589, Institut de Biologie Moléculaire et Cellulaire, Université de Strasbourg) M Martial Seveno (BioCampus Montpellier, University of Montpellier, CNRS, INSERM) S Serge Urbach (Institut de Génétique Fontionnel, University of Montpellier, CNRS, INSERM) K Kai Dallmeier (Katholic University Leuven, Department of Microbiology, Immunology and Transplantion, Rega Institute, Laboratory of Molecular Vaccinology and Vaccine Discovery) Éric Marois (Institute of Molecular and Cellular Biology, University of Strasbourg, CNRS, Inserm) J Julien Pompon (Maladies Infectieuses et Vecteurs: Ecologie, Génétique, Evolution et Controle, University of Montpellier, Institut of Research for development, CNRS)

Abstract

Viruses exploit extracellular vesicles (EVs) to transfer infection-enhancing viral RNAs. However, mechanisms underlying viral RNA loading remain elusive. We leveraged our previous discovery that dengue virus secretes transmission-enhancing subgenomic flaviviral RNA (sfRNA) into mosquito salivary EVs to investigate viral RNA loading mechanism. We demonstrate that sfRNA alone promotes the secretion of sfRNA-containing EVs marked by the mosquito EV biogenesis protein AeSyntenin, by applying microscopy and viral genetic editing in in vitro and in vivo models. SfRNA via its stem loop structures interacts intracellularly with mosquito AeSyntenin and this interaction is selectively maintained within EVs as shown by complementary RNA-affinity chromatography and RNA immunoprecipitation, and AI-based prediction. Finally, we used systemic and salivary gland-specific protein depletion to establish a functional role for mosquito AeSyntenin in exosome production and salivary secretion of sfRNA. We propose that sfRNA binds AeSyntenin to drive its selective packaging and release into exosomes, elucidating a mechanism for viral RNA incorporation into EVs.

Article Details

Volume / Issue Vol. 123, Issue 12
Published March 24, 2026
ISSN 0027-8424
Publisher National Academy of Sciences

Authors (23)

F

Florian Rachenne

Maladies Infectieuses et Vecteurs: Ecologie, Génétique, Evolution et Controle, University of Montpellier, Institut of Research for development, CNRS

N

Norman Schneider

Maladies Infectieuses et Vecteurs: Ecologie, Génétique, Evolution et Controle, University of Montpellier, Institut of Research for development, CNRS

F

Félix Rey-Cadilhac

Maladies Infectieuses et Vecteurs: Ecologie, Génétique, Evolution et Controle, University of Montpellier, Institut of Research for development, CNRS

I

Idalba Serrato-Pomar

Maladies Infectieuses et Vecteurs: Ecologie, Génétique, Evolution et Controle, University of Montpellier, Institut of Research for development, CNRS

L

Lauryne Pruvost

Maladies Infectieuses et Vecteurs: Ecologie, Génétique, Evolution et Controle, University of Montpellier, Institut of Research for development, CNRS

L

Laura Di Pietro

Maladies Infectieuses et Vecteurs: Ecologie, Génétique, Evolution et Controle, University of Montpellier, Institut of Research for development, CNRS

J

Jacques Dainat

Maladies Infectieuses et Vecteurs: Ecologie, Génétique, Evolution et Controle, University of Montpellier, Institut of Research for development, CNRS

A

Audrey Vernet

Plant Health Institute of Montpellier, University of Montpellier, Institut of Research for development

C

Chantal Cazevieille

Université Montpellier, INSERM U1298, Institute for Neurosciences of Montpellier

A

Aurélie Ancelin

Centre de Biologie Structurale, Electronic Microscopy Platform, CNRS

J

Joséphine Lai Kee Him

Centre de Biologie Structurale, Electronic Microscopy Platform, CNRS

S

Sander Jansen

Katholic University Leuven, Department of Microbiology, Immunology and Transplantion, Rega Institute, Laboratory of Molecular Vaccinology and Vaccine Discovery

E

Elliott F. Miot

Maladies Infectieuses et Vecteurs: Ecologie, Génétique, Evolution et Controle, University of Montpellier, Institut of Research for development, CNRS

J

Jérémy Fraering

Plateforme Protéomique Strasbourg-Esplanade, CNRS UAR1589, Institut de Biologie Moléculaire et Cellulaire, Université de Strasbourg

L

Laurianne Simon

Institut Charles Gerhardt Montpellier, University of Montpellier, CNRS, Ecole Nationale Supérieure de Chimie de Montpellier

D

Dorothée Missé

Maladies Infectieuses et Vecteurs: Ecologie, Génétique, Evolution et Controle, University of Montpellier, Institut of Research for development, CNRS

M

Marie Morille

Institut Charles Gerhardt Montpellier, University of Montpellier, CNRS, Ecole Nationale Supérieure de Chimie de Montpellier

P

Philippe Hammann

Plateforme Protéomique Strasbourg-Esplanade, CNRS UAR1589, Institut de Biologie Moléculaire et Cellulaire, Université de Strasbourg

M

Martial Seveno

BioCampus Montpellier, University of Montpellier, CNRS, INSERM

S

Serge Urbach

Institut de Génétique Fontionnel, University of Montpellier, CNRS, INSERM

K

Kai Dallmeier

Katholic University Leuven, Department of Microbiology, Immunology and Transplantion, Rega Institute, Laboratory of Molecular Vaccinology and Vaccine Discovery

Éric Marois

Institute of Molecular and Cellular Biology, University of Strasbourg, CNRS, Inserm

J

Julien Pompon

Maladies Infectieuses et Vecteurs: Ecologie, Génétique, Evolution et Controle, University of Montpellier, Institut of Research for development, CNRS