Mutational analysis of the R peptide cleavage site of Moloney murine leukaemia virus envelope protein.
Moloney murine leukaemia virus (MoMLV) enters host cells by membrane fusion between the viral envelope and the host cell membrane. The cytoplasmic tail (R peptide) of the MoMLV envelope protein (Env) is cleaved by the viral protease during virion maturation. R peptide-truncated Env induces syncytia in susceptible cells but R peptide-containing Env does not, indicating that the R peptide inhibits membrane fusion. To examine the function of amino acid residues at the R peptide cleavage site in virus entry, mutant Env expression plasmids containing amino acid substitutions at these cleavage site residues were constructed. Some of these mutants induced syncytia in NIH 3T3 cells, even though they expressed the R peptide, indicating the importance of these residues for membrane fusion inhibition by the R peptide. Some mutants in which R peptide cleavage was detected had comparable transduction efficiency to wild-type Env, but mutants in which R peptide cleavage was not detected had lower transduction efficiency than wild-type Env. This result strongly supports that R peptide cleavage is required for virus entry.
Kubo
Yoshinao
Y
Department of Preventive Medicine and AIDS Research, Institute of Tropical Medicine, Nagasaki University, 1-12-4 Sakamoto, Nagasaki 852-8523, Japan.|Molecular Cell Science Laboratory, RIKEN (The Institute of Physical and Chemical Research), Hirosawa 2-1, Wako, Saitama 351-0198, Japan.
Amanuma
Hiroshi
H
Molecular Cell Science Laboratory, RIKEN (The Institute of Physical and Chemical Research), Hirosawa 2-1, Wako, Saitama 351-0198, Japan.
D016475:3T3 Cells; D019943:Amino Acid Substitution; D000818:Animals; D002460:Cell Line; D005822:Genetic Vectors; D015726:Giant Cells; D008561:Membrane Fusion; D051379:Mice; D008979:Moloney murine leukemia virus / Q000472:pathogenicity*; D009842:Oligopeptides / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D014161:Transduction, Genetic; D014759:Viral Envelope Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism
D009842:Oligopeptides; C080708:R peptide; D014759:Viral Envelope Proteins