Document 0182
 DOCN  M9440182
 TI    Upstream U3 sequences in simian immunodeficiency virus are selectively
       deleted in vivo in the absence of an intact nef gene.
 DT    9404
 AU    Kirchhoff F; Kestler HW 3rd; Desrosiers RC; New England Regional Primate
       Research Center, Harvard Medical; School, Southborough, Massachusetts
       01772-9102.
 SO    J Virol. 1994 Mar;68(3):2031-7. Unique Identifier : AIDSLINE
       MED/94149905
 AB    Major transcriptional control elements are located within the U3 region
       of the long terminal repeats (LTRs) of lentivirus and other retroviral
       genomes. The nef auxiliary gene of simian immunodeficiency virus (SIV)
       and human immunodeficiency virus overlaps about 70% of the 450- to
       560-bp-long U3 region present in these primate lentiviruses. We analyzed
       viral DNA sequences present in rhesus monkeys infected with a mutant of
       SIVmac containing a 182-bp deletion in the region of nef that does not
       overlap the LTR. Between 50 and 100% of the viral DNA molecules in eight
       of nine monkeys infected for 16 or more months contained additional
       deletions of 111 to 302 bp within the 517-bp U3 region. These deletions
       were contained within a 334-bp region of U3 that is overlapped by the
       nef reading frame, and they did not affect the polypurine tract, the
       NF-kappa B binding site, or other sequence elements in this same region
       that are important for transcription and replication. Such deletions
       were not detected in any of 41 PCR amplifications from 8 rhesus monkeys
       infected with wild-type SIV for 8 to 26 months, nor were they detected
       in 10 animals infected with vpr, vpx or vpr-vpx deletion mutants. These
       results indicate that, in the absence of an intact nef gene, these
       upstream U3 sequences are not advantageous for the virus.
 DE    Animal  Base Sequence  Cloning, Molecular  Comparative Study  Genes,
       env/GENETICS  Genes, nef/*GENETICS  Genes, vpr/GENETICS
       Lentivirus/GENETICS  Leukocytes, Mononuclear/MICROBIOLOGY  Macaca
       mulatta  Molecular Sequence Data  Repetitive Sequences, Nucleic
       Acid/*GENETICS  *Selection (Genetics)  *Sequence Deletion  Simian
       Acquired Immunodeficiency Syndrome/*GENETICS  Support, Non-U.S. Gov't
       Support, U.S. Gov't, P.H.S.  Viral Regulatory Proteins/GENETICS  JOURNAL
       ARTICLE

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