home
***
CD-ROM
|
disk
|
FTP
|
other
***
search
/
Shareware Overload Trio 2
/
Shareware Overload Trio Volume 2 (Chestnut CD-ROM).ISO
/
dir26
/
med9410p.zip
/
M94A3281.TXT
< prev
next >
Wrap
Text File
|
1994-10-25
|
3KB
|
43 lines
Document 3281
DOCN M94A3281
TI Mutations of basic amino acids of NCp7 of HIV-1 affect RNA binding in
vitro.
DT 9412
AU Schmalzbauer E; Dannull J; Guehmann S; Moelling K; Max-Planck-Institute
for Molecular Genetics, Berlin, FRG.
SO Int Conf AIDS. 1994 Aug 7-12;10(1):111 (abstract no. PA0061). Unique
Identifier : AIDSLINE ICA10/94369294
AB OBJECTIVES: The nucleocapsid (NC) protein of human immundeficiency virus
type 1 (HIV-1) is necessary during virion assambly for core formation
and packaging of the viral genomic RNA dimer. The NC protein of HIV-1
contains two clusters of basic aminoacids consisting of five and four
aminoacid residues respectively, flanking the first of its two zinc
fingers. The importance of these particular aminoacids for the binding
of RNA was to be examined. METHODS: Towards this aim these aminoacid
residues have been mutagenized to neutral ones individually as well as
in various combinations by site-directed mutagenesis. Wild type NCp7 and
the mutant proteins were expressed as recombinant proteins in E. coli
with six histidines as tags at their aminotermini in order to allow
efficient purification. The purified proteins were analyzed for RNA
binding in vitro using HIV-1 5' leader RNA transcribed in vitro. Assays
comprised North-Western blots at various salt concentrations and filter
binding tests which allow determination of the dissociation constants of
the various mutants. RESULTS AND CONCLUSIONS: The results indicate for
the first time that mutation of the three distinct aminoacids R7, R32,
and K33 are more critical for RNA binding than others. Mutation of the
other aminoacid residues reduce the binding affinity proportionately to
the number of mutations. Mutation of 7 out of the total of 9 basic
aminoacid residues reduces the binding by 50 to 90-fold. Thus, in
planning the construction of possible antiviral therapeutics the unique
role of these three particular aminoacids should be considered.
DE Amino Acid Sequence Amino Acids/CHEMISTRY
Capsid/CHEMISTRY/*GENETICS/*METABOLISM Escherichia coli/GENETICS Gene
Products, gag/CHEMISTRY/*GENETICS/*METABOLISM Human Hydrogen-Ion
Concentration HIV-1/*GENETICS/*METABOLISM In Vitro Mutagenesis,
Site-Directed Recombinant Proteins/CHEMISTRY/GENETICS/METABOLISM RNA,
Viral/*METABOLISM Zinc Fingers/GENETICS MEETING ABSTRACT
SOURCE: National Library of Medicine. NOTICE: This material may be
protected by Copyright Law (Title 17, U.S.Code).