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Aggregation of polyA–HIV-1 nucleocapsid protein NCp7 complexes and properties of the aggregates

Published on Jul 1, 1999in Colloids and Surfaces A: Physicochemical and Engineering Aspects3.13
· DOI :10.1016/S0927-7757(98)00674-8
Stoyl P. Stoylov11
Estimated H-index: 11
(BAS: Bulgarian Academy of Sciences),
E Stoylova1
Estimated H-index: 1
(BAS: Bulgarian Academy of Sciences)
+ 9 AuthorsYves Mély52
Estimated H-index: 52
(CNRS: Centre national de la recherche scientifique)
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Abstract
Abstract We have previously shown that in solution, depending on solute and solution conditions, an ordered aggregation of polyA–NCp7 complexes takes place. The kinetic behaviour of the polyA(homoribopolynucleotide)–NCp7(human immunodeficiency virus-I nucleocapsid protein) aggregating system was studied at physiological NaCl concentration (150 mM) using quasielastic light scattering measurements. The kinetic curves were fitted to a power law equation. For the aggregate size growth with time at initial concentrations of NCp7=0.3 μM and nucleotide-to-protein molar ratios of 17 and 50 we obtained for power exponents of 0.15 and 0.23, respectively. On the basis of the aggregate size at which maxima are observed on the light scattering versus time curves we suggested a method for determining the mechanism of aggregation. Thus we found that in the process of polya–NCp7 aggregation, the growth proceeds by fusion of commensurable in size aggregates. The aggregate size dependence on NCp7 concentration showed critical behaviour. The calculated parameters of the power law (rate of growth n and a , related to the aggregate properties) showed in the critical region (0.2–0.3 μM NCp7) a marked change. Electro-optic measurements (electric birefringence and electric light scattering) gave no evidence for the existence of optically anisotropic and/or anisodiametric suspended aggregates under the experimental conditions accessible for the electro-optic instruments used. Quasielastic light scattering and electron microscopy studies showed that at all stages of aggregate growth, under a broad range of experimental conditions, the aggregates were spherical with a unimodal, relatively narrow size distribution. We consider that combining the method suggested by us for studying the mechanism of aggregation with electro-optic and electron microscopy studies might be helpful for modelling the HIV-1 nucleocapsid (composed of genomic RNA–NCp7 complexes) assembly as well as transfectious particles for gene transfer (vectors) or non-infectious particles as candidate vaccines.
  • References (41)
  • Citations (4)
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References41
Newest
Published on Dec 31, 2008in Protein Science2.42
Fadia Dib-Hajj1
Estimated H-index: 1
(A&M: Texas A&M University),
Raza Khan7
Estimated H-index: 7
(A&M: Texas A&M University),
David P. Giedroc44
Estimated H-index: 44
(A&M: Texas A&M University)
The nucleocapsid protein (NC) is the major genomic RNA binding protein that plays integral roles in the structure and replication of all animal retroviruses. In this report, select biochemical properties of recombinant Mason-Pfizer monkey virus (MPMV) and HIV-1 NCs are compared. Evidence is presented that two types of saturated Zn2 NC-polynucleotide complexes can be formed under conditions of low [NaCl] that differ in apparent site-size (n = 8 vs. n = 14). The formation of one or the other compl...
Published on Mar 1, 1998in Biopolymers1.84
Eric Le Cam29
Estimated H-index: 29
(CNRS: Centre national de la recherche scientifique),
Dominique Coulaud8
Estimated H-index: 8
(CNRS: Centre national de la recherche scientifique)
+ 7 AuthorsYves Mély52
Estimated H-index: 52
(CNRS: Centre national de la recherche scientifique)
NCp7, the nucleocapsid protein of the human immunodeficiency virus type 1, induces an ordered aggregation of RNAs, a mechanism that is thought to be involved in the NCp7-induced promotion of nucleic acid annealing. To further investigate this aggregation, the morphology and the properties of the NCp7-induced aggregates of the model RNA homoribopolymer, polyA, were investigated by electron microscopy in various conditions. In almost all the tested conditions, the aggregates were spherical and con...
Published on Aug 1, 1997in Journal of Virology4.32
Narasimhachar Srinivasakumar8
Estimated H-index: 8
,
Nathalie Chazal15
Estimated H-index: 15
+ 3 AuthorsDavid Rekosh33
Estimated H-index: 33
We describe the generation of stable human immunodeficiency virus type 1 (HIV-1)-packaging lines that constitutively express high levels of HIV-1 structural proteins in either a Rev-dependent or a Rev-independent fashion. These cell lines were used to assess gene transfer by using an HIV-1 vector expressing the hygromycin B resistance gene and to study the effects of Rev, Tat, and Nef on the vector titer. The Rev-independent cell lines were created by using gag-pol and env expression vectors tha...
Published on Jul 4, 1997in Journal of Biological Chemistry
Jin Kyung Kim11
Estimated H-index: 11
(UR: University of Rochester),
Chockalingam Palaniappan15
Estimated H-index: 15
(UR: University of Rochester)
+ 2 AuthorsRobert A. Bambara59
Estimated H-index: 59
(UR: University of Rochester)
Abstract We previously found that strand transfer by human immunodeficiency virus type 1 (HIV-1) reverse transcriptase (RT) is promoted at sites where RT pauses during synthesis. In this report, strand transfer is measured within the 5′ transactivation response region (TAR) of HIV-1 RNA. We hypothesized that the stable hairpin structure of TAR would induce RT pausing, promoting RNase H-directed cleavage of the template and subsequent transfer at that site. We further predicted that HIV-1 nucleoc...
Published on Apr 1, 1997in Biochemistry2.95
Thomas Kiefhaber40
Estimated H-index: 40
,
Annett Bachmann11
Estimated H-index: 11
+ 1 AuthorsClemens Wagner3
Estimated H-index: 3
A kinetic folding intermediate of hen lysozyme is shown to form in a nucleation/growth type of mechanism. Under native solvent conditions, a nucleated state is formed slowly during refolding (τ = 14 ± 1 ms at 0 M GdmCl) and is rapidly converted to the folding intermediate (τ = 300 ± 150 μs at 0 M GdmCl). Under these conditions the nucleated state represents a high-energy state compared to the folding intermediate (ΔΔG0 = 13.7 ± 3 kJ/mol). At elevated concentrations of GdmCl, the nucleated state ...
Y. Yamaguchi1
Estimated H-index: 1
(University of Bayreuth),
H. Hoffmann38
Estimated H-index: 38
(University of Bayreuth)
Abstract Saponite is a commercially available synthetic clay mineral that can easily be dispersed in water to a transparent solution. With increasing concentration the solutions show a sol-gel transition around 2 wt.%. The gels are rather stiff and have a high yield value. The saponite particles are present in the suspension as very thin bilayers with a thickness of about 10 A and a diameter of about 500 A. The bilayers have a relatively high negative charge density of about 0.9 meq g −1 . The p...
Published on Mar 1, 1997in Biopolymers1.84
Stoyl P. Stoylov11
Estimated H-index: 11
(CNRS: Centre national de la recherche scientifique),
Constance Vuilleumier7
Estimated H-index: 7
(CNRS: Centre national de la recherche scientifique)
+ 4 AuthorsYves Mély52
Estimated H-index: 52
(CNRS: Centre national de la recherche scientifique)
The nucleocapsid protein NCp7, which is the major genomic RNA binding protein of human immunodeficiency virus type 1, plays an important role in several key steps of the viral life cycle. Many of the NCp7 activities, notably the nucleic acid annealing and the genomic RNA wrapping ones, are thought to be linked to a nonspecific binding of NCp7 to its nucleic acid targets. The mechanism of these activities is still debated but several clues are in favor of an intermediate aggregation of nucleic ac...
Published on Feb 1, 1997in Archives of Virology2.26
T. Takasaki1
Estimated H-index: 1
(Kindai University),
I. Kurane2
Estimated H-index: 2
(Kindai University)
+ 2 AuthorsJ. Yamaguchi1
Estimated H-index: 1
(Kindai University)
The basic structure of human immunodeficiency virus type 1 (HIV-1) has been investigated morphologically; however, the internal structure of HIV-1 core is not well understood. We studied the internal structures by transmission electron microscopy. We modified the method for electron staining of ultrathin sections and processed electron microscopic photographs using a computer. We confirmed that a mature HIV-1 particle had two copies of RNA strands in a cone-shaped core. These two RNA strands for...
Published on Jan 1, 1997in New Journal of Chemistry3.07
Hemant M. Deshmukh2
Estimated H-index: 2
(University of Pittsburgh),
Leaf Huang91
Estimated H-index: 91
(University of Pittsburgh)
Published on Oct 1, 1996in Journal of Crystal Growth1.57
J.D. Ng7
Estimated H-index: 7
(CNRS: Centre national de la recherche scientifique),
Bernard Lorber28
Estimated H-index: 28
(CNRS: Centre national de la recherche scientifique)
+ 3 AuthorsRichard Giegé53
Estimated H-index: 53
(CNRS: Centre national de la recherche scientifique)
Abstract Crystals were obtained by different methods under conditions where nucleation and growth occur from precipitated macromolecular material. The phenomenon was observed with compounds of different size and nature, such as thaumatin, concanavalin A, an α-amylase, a thermostable aspartyl-tRNA synthetase, the nucleo-protein complex between a tRNA Asp transcript and its cognate yeast aspartyl-tRNA synthetase, and tomato bushy stunt virus. In each system, after a rather rapid precipitation step...
Cited By4
Newest
Published on Jan 1, 2012in Geoforum2.93
In this dissertation we discuss H-NS and its connection to nucleoid compaction and organization. Nucleoid formation involves a dramatic reduction in coil volume of the genomic DNA. Four factors are thought to influence coil volume: supercoiling, DNA charge neutralization, macromolecular crowding and DNA deformation by NAPs. This study focuses mainly on the latter two factors, and on their interplay. We investigate both direct and indirect changes in DNA coil volume as a result of H-NS binding to...
Yining Zeng19
Estimated H-index: 19
,
Hsiao-Wei Liu8
Estimated H-index: 8
+ 5 AuthorsPaul F. Barbara65
Estimated H-index: 65
Reverse transcription of the HIV-1 genome involves several nucleic acid rearrangement steps that are catalyzed (chaperoned) by the nucleocapsid protein (NC), including the annealing of the transactivation response region (TAR) RNA of the genome to the complementary sequence (TAR DNA) in minus-strand strong-stop DNA. It has been extremely challenging to obtain unambiguous mechanistic details on the annealing process at the molecular level because of the kinetic involvement of a complex and hetero...
Published on Mar 1, 2002in Journal of Molecular Biology5.07
Serena Bernacchi16
Estimated H-index: 16
(CNRS: Centre national de la recherche scientifique),
Stoyl P. Stoylov11
Estimated H-index: 11
(CNRS: Centre national de la recherche scientifique)
+ 4 AuthorsYves Mély52
Estimated H-index: 52
(CNRS: Centre national de la recherche scientifique)
Abstract The nucleocapsid protein NCp7 of HIV-1 possesses a nucleic acid chaperone activity that is critical in minus and plus strand transfer during reverse transcription. The minus strand transfer notably relies on the ability of NCp7 to destabilize the stable stem with five contiguous, double-stranded segments of both the TAR sequence at the 3′ end of the viral genome and the complementary sequence, cTAR, in minus strong-stop DNA. In order to examine the nature and the extent of NCp7 destabil...
Published on Jan 1, 2002in Journal of Molecular Biology5.07
Serena Bernacchi16
Estimated H-index: 16
(CNRS: Centre national de la recherche scientifique),
Stoyl P. Stoylov11
Estimated H-index: 11
(CNRS: Centre national de la recherche scientifique)
+ 4 AuthorsYves Mély52
Estimated H-index: 52
(CNRS: Centre national de la recherche scientifique)
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