       Document 0238
 DOCN  M9620238
 TI    Trans-dominant inhibitory human immunodeficiency virus type 1 protease
       monomers prevent protease activation and virion maturation.
 DT    9602
 AU    Babe LM; Rose J; Craik CS; Department of Pharmaceutical Chemistry,
       University of California,; San Francisco 94143, USA.
 SO    Proc Natl Acad Sci U S A. 1995 Oct 24;92(22):10069-73. Unique Identifier
       : AIDSLINE MED/96036025
 AB    Production of infectious human immunodeficiency virus (HIV) requires
       proper polyprotein processing by the dimeric viral protease. The
       trans-dominant inhibitory activity of a defective protease monomer with
       the active site Asp-25 changed to Asn was measured by transient
       transfection. A proviral plasmid that included the drug-selectable
       Escherichia coli gpt gene was used to deliver the wild-type (wt) or
       mutant proteases to cultured cells. Coexpression of the wt proviral DNA
       (HIV-gpt) with increasing amounts of the mutant proviral DNA (HIV-gpt
       D25N) results in a concomitant decrease in proteolytic activity
       monitored by in vivo viral polyprotein processing. The viral particles
       resulting from inactivation of the protease were mostly immature,
       consisting predominantly of unprocessed p55gag and p160gag-pol
       polyproteins. In the presence of HIV-1 gp160 env, the number of secreted
       noninfectious particles correlated with the presence of increasing
       amounts of the defective protease. Greater than 97% reduction in
       infectivity was observed at a 1:6 ratio of wt to defective protease DNA.
       This provides an estimate of the level of inhibition required for
       effectively preventing virion processing. Stable expression of the
       defective protease in monkey cells reduced the yield of infectious
       particles from these cells by 90% upon transfection with the wt proviral
       DNA. These results show that defective subunits of the viral protease
       exert a trans-dominant inhibitory effect resulting from the formation of
       catalytically compromised heterodimers in vivo, ultimately yielding
       noninfectious viral particles.
 DE    Animal  Asparagine  Aspartic Acid  Binding Sites  Cell Line
       Cercopithecus aethiops  DNA, Viral/METABOLISM  Gene Expression  Hela
       Cells  Human  HIV Protease/BIOSYNTHESIS/*METABOLISM
       HIV-1/ENZYMOLOGY/*PHYSIOLOGY  Kinetics  Macromolecular Systems  Point
       Mutation  Recombinant Proteins/BIOSYNTHESIS/METABOLISM  RNA,
       Viral/BIOSYNTHESIS  Support, Non-U.S. Gov't  Support, U.S. Gov't, P.H.S.
       Transfection  Virion/*PHYSIOLOGY  JOURNAL ARTICLE

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

