PML scientists have been involved in an exciting new research study which examines phytoplankton cell fate as a result of viral infection.
Phytoplankton are the basis of marine foodwebs and are responsible for nearly half the global primary production. The coccolithophore Emiliania huxleyi is a common species of phytoplankton and has an integral role in marine foodwebs. When conditions are favourable, coccolithophores have the capacity to form significant annual blooms. Viruses are now considered a major force in terminating these blooms.
Viruses are the most abundant biological entities in the marine environment and are incredibly important because of their significant role in controlling phytoplankton and bacterial populations and recycling nutrients. Until relatively recently there has been very little understanding of the relationship between Emiliania huxleyi and its virus (EhV) in the natural environment.
This study was conducted during a mesocosm experiment in Norwegian coastal waters organised by PML, which was set up to investigate host-virus interactions during a natural E. huxleyi bloom. The main aim of this current research was to determine the molecular mechanisms controlling phytoplankton host-virus interactions and the associated cell fate. Recently published laboratory studies demonstrated viral sphingolipid-based regulation of host-virus interactions through the induction and control of the host's programmed cell death (PCD) machinery. Here we assessed whether this molecular mechanism could also be observed in natural phytoplankton-virus populations and thus, potentially serve as a promising biomarker of viral infection.
This study is the first of its kind to investigate natural phytoplankton host-virus interactions at subcellular levels of resolution, and uses a diverse suite of molecular tools and in situ fluorescent staining to target different subcellular processes.
The results provide the first demonstration of PCD activation in natural populations and support the role of glycosphingolipids and programmed cell death in regulating E. huxleyi–EhV interactions.
PML scientist Dr Susan Kimmance was involved in the experimental research and analysis concerning viral-induced stress and mortality of E.huxleyi.
The results not only provide further mechanistic understanding of the regulation of natural host–virus interactions, but also a promising foundation for using unique lipid-based proxies and molecular biomarkers to quantify and constrain the influence of viral infection in the oceans.