       Document 0692
 DOCN  M9460692
 TI    Identification of the caprine arthritis encephalitis virus Rev protein
       and its cis-acting Rev-responsive element.
 DT    9404
 AU    Saltarelli MJ; Schoborg R; Pavlakis GN; Clements JE; Frederick Cancer
       Research and Development Center, Human; Retrovirus Section, Maryland
       21702.
 SO    Virology. 1994 Feb 15;199(1):47-55. Unique Identifier : AIDSLINE
       MED/94160580
 AB    Caprine Arthritis Encephalitis Virus (CAEV) is a lentivirus closely
       related to visna virus of sheep and more distantly related to the human
       lentivirus HIV-1. The genomes of lentiviruses contain additional genes
       that regulate the lentivirus gene expression; one of these is Rev, a
       protein that regulates the expression of viral proteins via
       post-transcriptional mechanisms. A cDNA clone was isolated from CAEV
       infected cells and shown to encode the 18-kDa Rev protein of CAEV.
       Antibodies against CAEV Rev (Rev-C) demonstrated that the CAEV Rev
       protein accumulated in the nucleus and in particular in the nucleolus of
       transiently transfected cells. Mutation of a basic region in the CAEV
       Rev protein resulted in loss of nucleolar localization. A highly
       structured RNA element has been identified in the env gene of CAEV (nt
       7850-8150); its structure and location suggested that it was analogous
       to the Rev-responsive element (RRE) of HIV-1 and visna virus. A 300-bp
       fragment (nt 7850-8150) spanning this region was substituted for the
       HIV-1 RRE in an HIV-1 Gag expression vector. Expression of the Gag
       protein was dramatically increased when Rev-C was added in trans,
       indicating that this fragment contained the cis-acting CAEV Rev
       Responsive Element. Cross-activation by the Rev/Rex proteins of other
       lentiviruses and members of the HTLV-I family indicated that this RRE
       could interact with Rev or Rex proteins of other viruses. This suggests
       that the highly divergent lentiviruses share similar mechanisms and
       cofactors regulating post-transcriptional viral gene expression. The
       Rev/RRE mechanism is thus the most conserved regulatory mechanism in
       lentiviruses and other complex retroviruses.
 DE    Amino Acid Sequence  Animal  Arthritis-Encephalitis Virus,
       Caprine/*GENETICS  Cloning, Molecular  DNA, Viral  Fluorescent Antibody
       Technique  Gene Products, rev/*GENETICS  Human  Molecular Sequence Data
       *Regulatory Sequences, Nucleic Acid  Support, U.S. Gov't, P.H.S.
       JOURNAL ARTICLE

       SOURCE: National Library of Medicine.  NOTICE: This material may be
       protected by Copyright Law (Title 17, U.S.Code).

