title: Investigation by fluorescence correlation spectroscopy of the chaperoning interactions of HIV-1 nucleocapsid protein with the viral DNA initiation sequences.
abstract: HIV-1 nucleocapsid protein (NC) exhibits nucleic acid chaperone properties that are important during reverse transcription. Herein, we review and extend our recent investigation by fluorescence correlation spectroscopy (FCS) of the NC chaperone activity on the primer binding site sequences (PBS) of the (-) and (+) DNA strands, which are involved in the second strand transfer during reverse transcription. In the absence of NC, the PBS stem-loops exhibited a fraying limited to the terminal G-C base pair. The kinetics of fraying were significantly activated by NC, a feature that may favour (-)PBS/(+)PBS annealing during the second strand transfer. In addition, NC was found to promote the formation of PBS kissing homodimers through interaction between the loops. These kissing complexes may favour secondary contacts between viral sequences and thus, promote recombination and viral diversity.
authors.affiliation: Laboratoire de pharmacologie et physico-chimie des interactions cellulaires et moléculaires, UMR 7034, CNRS, faculté de pharmacie, université Louis-Pasteur, Strasbourg-1, 74, route du Rhin, 67401 Illkirch cedex, France.
authors.forename: Caroline
authors.initials: C
authors.lastname: Egelé
authors.forename: Emmanuel
authors.initials: E
authors.lastname: Schaub
authors.forename: Etienne
authors.initials: E
authors.lastname: Piémont
authors.forename: Hugues
authors.initials: H
authors.lastname: de Rocquigny
authors.forename: Yves
authors.initials: Y
authors.lastname: Mély
mesh_terms: D001483:Base Sequence; D004279:DNA, Viral / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D015497:HIV-1 / Q000235:genetics / Q000378:metabolism*; D007700:Kinetics; D008958:Models, Molecular; D009690:Nucleic Acid Conformation; D019590:Nucleocapsid Proteins / Q000737:chemistry / Q000378:metabolism*; D010446:Peptide Fragments / Q000378:metabolism; D013050:Spectrometry, Fluorescence / Q000379:methods
chemical_list: D004279:DNA, Viral; D019590:Nucleocapsid Proteins; D010446:Peptide Fragments