Article

Identification of two amino acid residues on Ebola virus glycoprotein 1 critical for cell entry.

Gene Transfer and Immunogenicity Branch, Division of Cellular, Tissue and Gene Therapies, Center for Biologics Evaluation and Research, Food and Drug Administration, Bethesda, MD 20892, USA.
Virus Research (impact factor: 2.94). 12/2006; 121(2):205-14. DOI:10.1016/j.virusres.2006.06.002 pp.205-14
Source: PubMed

ABSTRACT Using site-directed mutagenesis and retroviral vector pseudotyping of the wild type or mutated glycoprotein of Zaire ebolavirus (ZEBOV), we analyzed 15 conserved residues in the N-terminus of the filovirus glycoprotein 1 (GP1) in order to identify residues critical for cell entry. Results from infectivity assays and Western blot analyses identified two phenylalanine residues at positions 88 and 159 that appear to be critical for ZEBOV entry in vitro. We extended this observation by introduction of alanines at either position 88 or 159 of Ivory Coast Ebolavirus (CIEBOV) and observed the same phenotype. Further, we showed that introduction of each of the two mutations in a recombinant full-length clone of ZEBOV (Mayinga strain) that also carried the coding sequence for GFP could not be rescued, suggesting the mutants rendered the virus non-infectious. The two phenylalanines that are critical for both ZEBOV and CIEBOV entry are found in two linear domains of GP1 that are highly conserved among filoviruses, and thus could provide a target for rational development of broadly cross-protective vaccines or antiviral therapies.

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Keywords

antiviral therapies
 
CIEBOV entry
 
coding sequence
 
cross-protective vaccines
 
filovirus glycoprotein 1
 
filoviruses
 
infectivity assays
 
Ivory Coast Ebolavirus
 
linear domains
 
Mayinga strain
 
mutated glycoprotein
 
rational development
 
recombinant full-length clone
 
residues critical
 
retroviral vector pseudotyping
 
site-directed mutagenesis
 
two mutations
 
two phenylalanines
 
Zaire ebolavirus
 
ZEBOV entry
 

Onesmo M Mpanju