       Document 0575
 DOCN  M9640575
 TI    Avian sarcoma leukemia virus protease linked to the adjacent Gag
       polyprotein is enzymatically active.
 DT    9604
 AU    Arad G; Bar-Meir R; Almog N; Chorev M; Kotler M; Department of Molecular
       Genetics, Hebrew University, Hadassah; Medical School, Jerusalem,
       Israel.
 SO    Virology. 1995 Dec 20;214(2):439-44. Unique Identifier : AIDSLINE
       MED/96130183
 AB    The activity of avian sarcoma leukemia virus (ASLV) protease (PR) prior
       to its release from the precursor protein was determined by introducing
       mutations at the cleavage site between PR and the adjacent upstream
       nucleocapsid (NC) protein. Gag DNA fragments containing these mutations
       were cloned into expression vectors and introduced into Escherichia coli
       in which the ASLV proteins were expressed. The dipeptide NC-PR
       containing these mutations did not undergo autoprocessing when expressed
       in bacterial cells and the fused proteins were devoid of enzymatic
       activity. However, when the whole Gag polyprotein containing these
       mutations was expressed in bacterial cells, other PR cleavage sites in
       the viral Gag polyprotein underwent normal cleavage, indicating that the
       release of free PR is not a prerequisite for correct processing of the
       ASLV Gag precursor.
 DE    Animal  Binding Sites  Catalysis  Escherichia coli  Gene Expression
       Regulation, Viral  Gene Products, gag/GENETICS/*METABOLISM  Mutation
       Peptide Peptidohydrolases/GENETICS/*METABOLISM  Peptides/METABOLISM
       *Protein Processing, Post-Translational  Recombinant
       Proteins/GENETICS/METABOLISM  Sarcoma Viruses,
       Avian/*ENZYMOLOGY/GENETICS  Substrate Specificity  Support, Non-U.S.
       Gov't  Viral Core Proteins/GENETICS/METABOLISM  JOURNAL ARTICLE

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

