Solid-state NMR data support a helix-loop-helix structural model for the N-terminal half of HIV-1 Rev in fibrillar form.
J Mol Biol
; 313(4): 845-59, 2001 Nov 02.
Article
em En
| MEDLINE
| ID: mdl-11697908
ABSTRACT
Rev is a 116 residue basic protein encoded by the genome of human immunodeficiency virus type 1 (HIV-1) that binds to multiple sites in the Rev response element (RRE) of viral mRNA transcripts in nuclei of host cells, leading to transport of incompletely spliced and unspliced viral mRNA to the cytoplasm of host cells in the latter phases of the HIV-1 life cycle. Rev is absolutely required for viral replication. Because Rev aggregates and fibrillizes in solution at concentrations required for crystal growth or liquid state NMR measurements, high-resolution structural characterization of full-length Rev has not been possible. Previously, circular dichroism studies have shown that approximately 50 % of the Rev sequence adopts helical secondary structure, predicted to correspond to a helix-loop-helix structural motif in the N-terminal half of the protein. We describe the application of solid-state NMR techniques to Rev fibrils as a means of obtaining site-specific, atomic-level structural constraints without requiring a high degree of solubility or crystallinity. Solid-state NMR measurements, using the double-quantum chemical shift anisotropy and constant-time double-quantum-filtered dipolar recoupling techniques, provide constraints on the phi and psi backbone dihedral angles at sites in which consecutive backbone carbonyl groups are labeled with (13)C. Quantitative analysis of the solid-state NMR data, by comparison with numerical simulations, indicates helical phi and psi angles at residues Leu13 and Val16 in the predicted helix 1 segment, and at residues Arg39, Arg 42, Arg43, and Arg44 in the predicted helix 2 segment. These data represent the first site-specific structural constraints from NMR spectroscopy on full-length Rev, and support the helix-loop-helix structural model for its N-terminal half.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Produtos do Gene rev
/
HIV-1
/
Sequências Hélice-Alça-Hélice
/
Ressonância Magnética Nuclear Biomolecular
Tipo de estudo:
Prognostic_studies
Idioma:
En
Revista:
J Mol Biol
Ano de publicação:
2001
Tipo de documento:
Article
País de afiliação:
Estados Unidos