Copyright : Laboratoire LEMAR- 2018
Anne-Claire Baudoux (CR CNRS, station biologique de Roscoff, AD2M), Brivaëla Moriceau (WP5, Impact of viral infection on diatom fate)
National
ANR AAPG2022
Start Date
04/04/2025
End Date
04/04/2025
Viruses have global biogeochemical impacts mainly through the mortality (lysis) and metabolic reprogramming of their microbial hosts. Viral lysis modulates food web dynamics by stealing living biomass from higher trophic levels and redirecting it into the microbial loop. This "viral shunt" is one of the major carbon flows in the ocean. Viruses also affect nutrient cycling during infection, diverting host metabolism to viral production. This reprogramming profoundly alters resource acquisition, carbon and energy metabolism and thus the ecological niche of infected cells. This knowledge is based almost exclusively on the study of viruses containing DNA genomes. Although RNA viruses represent a significant fraction of the marine virosphere (around half), their functional role remains poorly understood. BONUS proposes to study this under-explored component of the biosphere and its biogeochemical impacts on key organisms in the ocean, the diatoms. Diatoms are responsible for 40% of marine primary production and are heavily involved in carbon export. Our 4-year project proposes a detailed study of viral infection in two dominant diatom species with different life traits (large vs. small) and occurrence patterns (bloom-forming vs. persistent), and will test the hypothesis that viral infection profoundly alters diatom metabolism and physiology, and consequently their ecological and biogeochemical fate. To achieve this, a multidisciplinary research team will address 4 main questions:
1- What are the metabolic functions that respond to viral infection?
2- What is the impact on resource uptake and allocation?
3- Do diatoms infection favour recycling of organic matter at the ocean surface or the export of carbon, a process limiting global warming through the biological pump ?
4- What is the significance of viral infection and metabolic reprogramming in natural diatom populations?
Given the global-scale prominence of RNA viruses and targeted diatom populations, our research will lead to the discovery of important processes that significantly impact the flow of carbon and nutrients in the ocean.
Laboratory Members
Contributors
AD2M : Anne-Claire Baudoux, Nathalie Simon, Christophe Six, Florence Le Gall, Marie Walde, Estelle Bigeard
MIO : Guillaume Blanc, Christelle Desnues, Sonia Monteil
SBR : Erwan Corre, Charlotte Berthelier, Ian Probert, Cedric Leroux
LPCV : Johan Decelle
MNHN : Martine Boccara
© Jennifer LAURENT | UBO