title: Subcellular localization of the interaction between the human immunodeficiency virus transactivator Tat and the nucleosome assembly protein 1.
abstract: The histone chaperone nucleosome assembly protein, hNAP-1, is a host cofactor for the activity of the human immunodeficiency virus type 1 (HIV-1) transactivator Tat. The interaction between these two proteins has been shown to be important for Tat-mediated transcriptional activation and for efficient viral infection. Visualization of HIV-1 transcription and fluorescence resonance energy transfer experiments performed in this work demonstrate that hNAP-1 is not recruited to the site of Tat activity but the two proteins interact at the nuclear rim. These data are consistent with a mechanism that requires hNAP-1 for the transport of Tat within the nucleus rather than for the remodeling of nucleosomes on the provirus. Protein-protein docking and molecular modeling of the complex suggest that this interaction occurs between the basic domain of Tat and the histone-binding domain. The combination of theoretical and whole cell studies provided new insights into the functional significance of the Tat:hNAP-1 recognition.
authors.affiliation: Laboratory of Molecular Virology, International Centre for Genetic Engineering and Biotechnology (ICGEB), Padriciano, 99, 34012, Trieste, Italy.
authors.forename: Alex
authors.initials: A
authors.lastname: De Marco
authors.forename: Pablo D
authors.initials: PD
authors.lastname: Dans
authors.forename: Anna
authors.initials: A
authors.lastname: Knezevich
authors.forename: Paolo
authors.initials: P
authors.lastname: Maiuri
authors.forename: Sergio
authors.initials: S
authors.lastname: Pantano
authors.forename: Alessandro
authors.initials: A
authors.lastname: Marcello
mesh_terms: D001483:Base Sequence; D005455:Fluorescent Antibody Technique; D015696:Gene Products, tat / Q000378:metabolism*; D006678:HIV / Q000378:metabolism*; D006801:Humans; D056490:Nucleosome Assembly Protein 1 / Q000378:metabolism*; D034741:RNA, Small Interfering; D013347:Subcellular Fractions / Q000378:metabolism*
chemical_list: D015696:Gene Products, tat; D056490:Nucleosome Assembly Protein 1; D034741:RNA, Small Interfering