The "putative" leucine zipper region of murine leukemia virus transmembrane protein (P15e) is essential for viral infectivity.
In order to determine the role of the putative leucine zipper region of murine leukemia virus (MLV) transmembrane protein p15E, nine mutations in this region were introduced by site-directed mutagenesis. None of these mutations affected the expression or transport of the envelope protein or incorporation into virions. The mutants were analyzed for their ability to infect NIH3T3 cells and to induce cell fusion in a rat XC cell fusion assay. Mutations removing the charge of the hydrophilic residues reduced infectivity in NIH3T3 cells but had either no effect or a minor effect on envelope-induced XC cell fusion. Six mutations of hydrophobic residues of the putative leucine zipper region were constructed; four completely abolished the ability to infect NIH3T3 cells and these mutant envelopes were also unable to induce cell fusion in the XC cell fusion assay. These data demonstrate the absolute requirement for the putative leucine zipper region for both fusion and infection of MLV.
Ramsdale
E E
EE
Department of Biochemistry, University of Oxford, United Kingdom.
Kingsman
S M
SM
Kingsman
A J
AJ
D016475:3T3 Cells; D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D001665:Binding Sites; D017931:DNA Primers; D016350:Leucine Zippers / Q000235:genetics / Q000502:physiology*; D009052:Leukemia Virus, Murine / Q000472:pathogenicity*; D008561:Membrane Fusion; D051379:Mice; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D051381:Rats; D015682:Retroviridae Proteins, Oncogenic / Q000235:genetics / Q000502:physiology*; D014407:Tumor Cells, Cultured; D014759:Viral Envelope Proteins / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D014771:Virion; D019065:Virus Assembly
D017931:DNA Primers; D015682:Retroviridae Proteins, Oncogenic; D014759:Viral Envelope Proteins; C078678:p15E protein, Murine leukemia virus