Single amino acid substitutions in the glycoprotein B carboxy terminus influence the fusion from without property of herpes simplex virus type 1.
Syncytial mutations of herpes simplex virus type 1 (HSV-1) strains ANG, ANG path, HFEM, tsB5 and HSZP cause extensive cell fusion and were mapped to the cytoplasmic domain of glycoprotein B (gB), within the syn 3 locus. These strains are so far the only ones which show the phenotype 'fusion from without' (FFWO): 60 min after infection with high m.o.i., cells in a tissue culture are fused without transcription and translation of the viral genome. In this report we detected, using the recombinants 27/III and K-7, that an amino acid exchange from Ala to Val at aa position 854 of gB is the main determinant for FFWO activity of strains ANG, ANG path and recombinant K-7. The transfer of this mutation to wild-type strains KOS and 17 syn+ by co-transfection results in recombinants KOS-854Q, 17-syn3, 17-syn3a and 17-syn3b. As a selection marker we used the cyclosporin A resistance of fusion which was shown to be a unique characteristic of syn 3 locus mutants. The recombinants show the FFWO phenotype in BHK cells but not in Vero cells. FFWO was shown to be cell-type dependent by comparing the number of p.f.u. needed to induce FFWO in various cell types.
Lingen
M
M
Johannes-Gutenberg Universität Mainz, Institut fur Virologie, Germany.
Seck
T
T
Weise
K
K
Falke
D
D
D000409:Alanine / Q000235:genetics; D000595:Amino Acid Sequence; D000596:Amino Acids / Q000235:genetics*; D000818:Animals; D002459:Cell Fusion / Q000235:genetics; D002522:Chlorocebus aethiops; D006224:Cricetinae; D003588:Cytopathogenic Effect, Viral / Q000235:genetics; D004797:Enzyme-Linked Immunosorbent Assay; D018259:Herpesvirus 1, Human / Q000737:chemistry* / Q000235:genetics* / Q000502:physiology; D007668:Kidney / Q000821:virology; D010641:Phenotype; D011995:Recombination, Genetic; D015183:Restriction Mapping; D014633:Valine / Q000235:genetics; D014709:Vero Cells; D014759:Viral Envelope Proteins / Q000737:chemistry / Q000235:genetics*
D000596:Amino Acids; D014759:Viral Envelope Proteins; C044525:glycoprotein B, herpes simplex virus type 2; D014633:Valine; D000409:Alanine