1.G.12.2.5
The small secreted glycoprotein GP2 of 364 aas, containing the viroporin, GP2-δ, the last 40 aas of GP2 of Zaire ebolavirus (He et al. 2017). This nonstructural polypeptide, called the delta peptide, is produced in abundance during Ebola virus infection. Full length and conserved C-terminal delta peptide fragments permeabilize the plasma membranes of nucleated cells, increase ion permeability across confluent cell monolayers and permeabilize synthetic lipid bilayers. Permeabilization activity is dependent on the disulfide bond between the two conserved cysteines. The conserved C-terminal portion of the peptide is biochemically stable in human serum, and most serum-stable fragments have full activity (He et al. 2017). This glycoprotein interacts with cholesterol to enhance membrane fusion and cell entry (Lee et al. 2021).