Molecular Mechanism of HIV-1 Vpr for Binding to Importin-α. Issue 13 (3rd July 2016)

• Record Type: Journal Article
• Authors: Miyatake, Hideyuki; Sanjoh, Akira; Murakami, Tomoyuki; Murakami, Hironobu; Matsuda, Go; Hagiwara, Kyoji; Yokoyama, Masaru; Sato, Hironori; Miyamoto, Yoichi; Dohmae, Naoshi; Aida, Yoko
• Is Part Of: Journal of molecular biology. Volume 428:Issue 13(2016:Jul. 01)
• Page Start: 2744
• Page End: 2757
• Publication Date: 2016-07-03
• Subjects: Vpr viral protein R -- HIV-1 human immunodeficiency virus type 1 -- NLS nuclear localization signal -- h-importin-α1 human importin-α1 -- IBB importin-β-binding -- ARM armadillo -- GST glutathione S-transferase -- ITC isothermal titration calorimetry -- DLS dynamic light scattering -- PBS phosphate-buffered saline; HIV-1 -- accessory gene products -- Vpr -- importin-α -- induced-fit binding; Molecular biology -- Periodicals; Biology -- Periodicals; Biochemistry -- Periodicals; Bacteriology -- Periodicals; Molecular Biology -- Periodicals; Biochemistry -- Periodicals; Biologie moléculaire -- Périodiques; Biologie -- Périodiques; Biochimie -- Périodiques; Moleculaire biologie; Biochemistry; Biology; Molecular biology; Periodicals; 572.805
• DOI: 10.1016/j.jmb.2016.05.003
• Languages: English
• ISSNs: 0022-2836

Abstract

Abstract: Viral protein R (Vpr) is an accessory gene product of human immunodeficiency virus type 1 (HIV-1) that plays multiple important roles associated with viral replication. Structural studies using NMR have revealed that Vpr consists of three α-helices and contains flexible N- and C-termini. However, the molecular mechanisms associated with Vpr function have not been elucidated. To investigate Vpr multifunctionality, we performed an X-ray crystallographic study of Vpr complexes containing importin-α, a known Vpr binding partner present in host cells. Elucidation of the crystal structure revealed that the flexible C-terminus changes its conformation to a twisted β-turn via an induced-fit mechanism, enabling binding to a minor nuclear localization signal (NLS) site of importin-α. The Vpr C-terminus can also bind with major NLS sites of importin-α in an extended conformation in different ways. These results, which represent the first reported crystallographic analysis of Vpr, demonstrate the multifunctional aspects that enable Vpr interaction with a variety of cellular proteins. Graphical Abstract: Highlights: Crystal complex structure of HIV-1 Vpr C-terminal and importin-α Vpr C-terminal loop makes a twisted β-turn upon binding to importin-α, inducing homodimerization of importin-α. The twisted β-turn mimics a canonical NLS-binding motif for the minor NLS-binding site of importin-α. The major NLS-binding site free from the Vpr binding passively serves as the canonical NLS-binding site during pre-integration complex nuclear import.