1. Properties and growth mechanism of the ordered aggregation of a model RNA by the HIV-1 nucleocapsid protein: An electron microscopy investigation
- Author
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Stoyl P. Stoylov, Eric Le Cam, Dominique Coulaud, Patrice Petitjean, Etienne Delain, Yves Mély, Elena Stoylova, Dominique Gerard, C. Vuilleumier, Bernard P. Roques, Le Cam, Eric, Groupe Réparation des Lésions Radio- et Chimio-lnduites [IGR, Villejuif], Institut Gustave Roussy (IGR)-Centre National de la Recherche Scientifique (CNRS), Pharmacochimie moléculaire et structurale, Institut des sciences du Médicament -Toxicologie - Chimie - Environnement (IFR71), Institut de Recherche pour le Développement (IRD)-Ecole Nationale Supérieure de Chimie de Paris - Chimie ParisTech-PSL (ENSCP), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Descartes - Paris 5 (UPD5)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Ecole Nationale Supérieure de Chimie de Paris - Chimie ParisTech-PSL (ENSCP), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Descartes - Paris 5 (UPD5)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Descartes - Paris 5 (UPD5)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Biophysique [Illkirch] (URA 491 CNRS), Centre National de la Recherche Scientifique (CNRS), Institut National de la Santé et de la Recherche Médicale (INSERM)-Ecole Nationale Supérieure de Chimie de Paris - Chimie ParisTech-PSL (ENSCP), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Paris Descartes - Paris 5 (UPD5)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Ecole Nationale Supérieure de Chimie de Paris - Chimie ParisTech-PSL (ENSCP), and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Paris Descartes - Paris 5 (UPD5)-Université Paris Descartes - Paris 5 (UPD5)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS) more...
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[SDV]Life Sciences [q-bio] ,Biophysics ,Nucleation ,Gene Products, gag ,gag Gene Products, Human Immunodeficiency Virus ,Biochemistry ,law.invention ,Biomaterials ,Viral Proteins ,Capsid ,law ,Molecule ,Nucleotide ,Particle Size ,ComputingMilieux_MISCELLANEOUS ,chemistry.chemical_classification ,Fusion ,Binding Sites ,Chemistry ,Organic Chemistry ,RNA ,Zinc Fingers ,General Medicine ,3. Good health ,Amorphous solid ,Molecular Weight ,[SDV] Life Sciences [q-bio] ,Microscopy, Electron ,Crystallography ,HIV-1 ,Nucleic acid ,Capsid Proteins ,Electron microscope ,Poly A - Abstract
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 consisted of a central dense core surrounded by a less dense halo made of NCp7-covered polyA molecules. The formation of these aggregates with a narrow distribution of sizes constitutes a distinctive feature of NCp7 over other single-stranded nucleic acid binding proteins. In most conditions, at the shortest times that can be reached experimentally, all the polyA molecules were already incorporated in small aggregates, suggesting that the nucleation step and the first aggregation events took place rapidly. The aggregates then orderly grew with time by fusion of the smaller aggregates to give larger ones. The aggregate halo was important in the fusion process by initiating the bridging between the colliding aggregates. In the presence of an excess of protein, the aggregates grew rapidly but were loosely packed and dissociated easily, suggesting adverse protein-protein interactions in the aggregates obtained in these conditions. In the presence of an excess of nucleotides, the presence of both amorphous nonspherical and slowly growing spherical aggregates suggested some changes in the mechanism of aggregate growth due to an incomplete covering of polyA molecules by NCp7. Finally, we showed that in the absence of added salt, the aggregate fusions were unfavored but not the initial events giving the first aggregates, the reverse being true in the presence of high salt concentrations (≥300 mM). © 1998 John Wiley & Sons, Inc. Biopoly 45: 217–229, 1998 more...
- Published
- 1998
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