Molecular Mechanism of HIV-1 Vpr for Binding to Importin-alpha
Miyatake, H., Sanjoh, A., Murakami, T., Murakami, H., Matsuda, G., Hagiwara, K., Yokoyama, M., Sato, H., Miyamoto, Y., Dohmae, N., Aida, Y.(2016) J Mol Biol 428: 2744-2757
- PubMed: 27181198 
- DOI: https://doi.org/10.1016/j.jmb.2016.05.003
- Primary Citation of Related Structures:  
5B56 - PubMed 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.
Organizational Affiliation: 
Nano Medical Engineering Laboratory, RIKEN, 2-1 Hirosawa, Wako-shi, Saitama 351-0198, Japan. Electronic address: miyatake@riken.jp.