Authors: Martha Powell, Future Science Group
Researchers from Tulane University (LA, USA) have uncovered the biological activity of an Ebola virus protein, demonstrating that it may play a role in the pathogenesis of the disease.
Currently, there is no effective, widely-available treatment for Ebola. The team from Tulane argued that in order to facilitate the development of therapies we need a better understanding of the disease’s pathogenesis. This study, published in the Journal of Virology, therefore hoped to characterize a viral protein produced in abundance during Ebola infections whose function has previously been unknown. Earlier studies analyzing the Ebola virus genome have suggested the protein, termed the delta peptide, could be a viroprotein – a family of proteins that play crucial role in the virulence and pathogenesis of many viruses.
Utilizing a protein marker that only fluoresces when it has crossed a plasma membrane the team could visualize cell permeability. The researchers assessed the effect of purified delta peptide on cells from humans, rodents, dogs and non-human primates.
They discovered that both full length delta peptide and conserved C-terminal fragments increased ion permeability across cell monolayers and also permeablized synthetic lipid bilayers. These findings suggest that delta peptide acts as a viroprotein – damaging host cells via permeablization.
This study is the first to characterize delta peptide, and the information uncovered suggests this viroprotein may have a critical role in the pathogenesis of Ebola. The researchers hope these findings could lead to novel countermeasures being developed that act against delta peptide.
Senior author William Wimley (Tulane University School of Medicine) concluded: “Our leading hypothesis is that the delta peptide affects the gastrointestinal tract by damaging cells after its release from infected cells. This effect may be a major contributor to the severe GI illness of patients with the Ebola virus.”
Sources: He J, Melnik LI, Komain A et al. Ebola Virus Delta Peptide is a Viroporin. J Virol. doi:10.1128/JVI.00438-17 (Epub ahead of print) (2017); http://news.tulane.edu/pr/tulane-researchers-help-find-possible-explanation-unparalleled-spread-ebola-virus