The Y-S-L-I tyrosine-based motif in the cytoplasmic domain of the human T-cell leukemia virus type 1 envelope is essential for cell-to-cell transmission.
The human T-cell leukemia virus type 1 (HTLV-1) transmembrane glycoprotein has a 24-amino-acid cytoplasmic domain whose function in the viral life cycle is poorly understood. We introduced premature-stop mutations and 18 single-amino-acid substitutions into this domain and studied their effects on cell-to-cell transmission of the virus. The results show that the cytoplasmic domain is absolutely required for cell-to-cell transmission of HTLV-1, through amino acids which cluster in a Y-S-L-I tyrosine-based motif. The transmission defect in two motif mutants did not result from a defect in glycoprotein incorporation or fusion. It appears that the Y-S-L-I tyrosine-based motif of the HTLV-1 glycoprotein cytoplasmic domain has multiple functions, including involvement in virus transmission at a postfusion step.
Delamarre
L
L
INSERM U332, Institut Cochin de Génétique Moléculaire, Paris, France.
Pique
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C
Rosenberg
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Blot
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Grange
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Le Blanc
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Dokhélar
M C
MC
D020816:Amino Acid Motifs; D000595:Amino Acid Sequence; D003593:Cytoplasm; D015726:Giant Cells / Q000502:physiology; D006023:Glycoproteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D015368:Human T-lymphotropic virus 1 / Q000235:genetics / Q000472:pathogenicity / Q000502:physiology*; D006801:Humans; D008561:Membrane Fusion; D008969:Molecular Sequence Data; D017434:Protein Structure, Tertiary; D014443:Tyrosine / Q000737:chemistry*; D014759:Viral Envelope Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D014771:Virion / Q000378:metabolism
D006023:Glycoproteins; D014759:Viral Envelope Proteins; D014443:Tyrosine