Trafficking to the plasma membrane of the seven-transmembrane protein encoded by human herpesvirus 6 U51 gene involves a cell-specific function present in T lymphocytes.
The sequence of human herpesvirus 6 (HHV-6) U51 open reading frame predicts a protein of 301 amino acid residues with seven transmembrane domains. To identify and characterize U51, we derived antipeptide polyclonal antibodies and developed a transient expression assay. We ascertained that U51 was synthesized in cord blood mononuclear cells infected with either variant A- or variant B-HHV-6 and was transported to the surface of productively infected cells. When synthesized in transient expression systems, U51 intracellular trafficking was regulated in a cell-type-dependent fashion. In human monolayer HEK-293 and 143tk- cells, U51 accumulated predominantly in the endoplasmic reticulum and failed to be transported to the cell surface. In contrast, in T-lymphocytic cell lines J-Jhan, Molt-3, and Jurkat, U51 was successfully transported to the plasma membrane. We infer that transport of U51 to the cell surface requires a cell-specific function present in activated T lymphocytes and T-cell lines.
Menotti
L
L
Section on Microbiology and Virology, Department of Experimental Pathology, University of Bologna, Bologna, Italy.
Mirandola
P
P
Locati
M
M
Campadelli-Fiume
G
G
D000818:Animals; D001692:Biological Transport; D002462:Cell Membrane / Q000821:virology; D002522:Chlorocebus aethiops; D015654:Herpesvirus 6, Human / Q000502:physiology*; D006801:Humans; D016366:Open Reading Frames; D012333:RNA, Messenger / Q000032:analysis; D013601:T-Lymphocytes / Q000821:virology*; D014162:Transfection; D014709:Vero Cells; D014759:Viral Envelope Proteins / Q000235:genetics / Q000378:metabolism*
D012333:RNA, Messenger; D014759:Viral Envelope Proteins