home
***
CD-ROM
|
disk
|
FTP
|
other
***
search
/
The Arsenal Files 6
/
The Arsenal Files 6 (Arsenal Computer).ISO
/
health
/
med9604b.zip
/
M9640751.TXT
< prev
next >
Wrap
Text File
|
1996-03-04
|
3KB
|
44 lines
Document 0751
DOCN M9640751
TI Functional analysis of the phosphorylation sites on the human
immunodeficiency virus type 1 Vpu protein.
DT 9604
AU Friborg J; Ladha A; Gottlinger H; Haseltine WA; Cohen EA; Departement de
Microbiologie et Immunologie, Faculte de; Medecine, Universite de
Montreal, Quebec, Canada.
SO J Acquir Immune Defic Syndr Hum Retrovirol. 1995 Jan 1;8(1):10-22.
Unique Identifier : AIDSLINE MED/96142196
AB The human immunodeficiency virus type 1 (HIV-1)-encoded vpu product is a
small class 1 integral membrane protein that is phosphorylated by the
ubiquitous casein kinase II (CKII) in HIV-1-infected cells. The Vpu
protein facilitates the release of budding virions from the surface of
infected cells and delays the rate of syncytium formation. In this
study, we investigated the role of phosphorylation in the biological
activity of Vpu. Our results show that phosphorylation of Vpu occurs on
serine residues at positions 52 and 56 located in a highly conserved
dodecapeptide sequence. Mutation of either Ser 56, or both Ser 52 and
Ser 56 impaired the ability of Vpu to delay the rate of syncytium
formation while retaining virion release activity at levels comparable
to vpu+ proviruses. Flow cytometry analysis indicates that the relative
amounts of envelope glycoprotein gp120 expressed at the surface of cells
transfected with these vpu mutant proviruses was two- to threefold
greater than that observed on cells transfected with a vpu+ provirus.
This increased expression of gp120 at the cell surface may explain the
more rapid onset of syncytium formation observed in cell transfected
with vpu mutant proviruses. These results suggest that Vpu-facilitated
virion release and delayed cytopathic effect are the consequence of two
distinct functional activities of the protein.
DE Amino Acid Sequence Base Sequence Cell Fusion Cell Line Consensus
Sequence Conserved Sequence CD4-Positive T-Lymphocytes/*VIROLOGY DNA
Mutational Analysis DNA Primers/CHEMISTRY DNA, Viral/ANALYSIS
Electrophoresis, Agar Gel Flow Cytometry Gene Products,
vpu/CHEMISTRY/*METABOLISM Giant Cells/VIROLOGY Human HIV Envelope
Protein gp120/BIOSYNTHESIS HIV-1/*PHYSIOLOGY Molecular Sequence Data
Peptide Fragments/CHEMISTRY Phosphorylation Proviruses Support,
Non-U.S. Gov't Support, U.S. Gov't, P.H.S. Transfection Virus
Replication/PHYSIOLOGY JOURNAL ARTICLE
SOURCE: National Library of Medicine. NOTICE: This material may be
protected by Copyright Law (Title 17, U.S.Code).