Open AccessThe Interaction between tRNALys3 and the Primer Activation Signal Deciphered by NMR Spectroscopy
Author(s) -
Dona Sleiman,
Pierre Barraud,
Franck Brachet,
Carine Tisné
Publication year - 2013
Publication title -
plos one
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.99
H-Index - 332
ISSN - 1932-6203
DOI - 10.1371/journal.pone.0064700
Subject(s) - primer binding site , nucleotide , rna , primer (cosmetics) , biology , nuclear magnetic resonance spectroscopy , transcription (linguistics) , reverse transcriptase , chemistry , microbiology and biotechnology , genetics , gene , stereochemistry , linguistics , philosophy , organic chemistry
The initiation of reverse transcription of the human immunodeficiency virus type 1 (HIV-1) requires the opening of the three-dimensional structure of the primer tRNA Lys 3 for its annealing to the viral RNA at the primer binding site (PBS). Despite the fact that the result of this rearrangement is thermodynamically more stable, there is a high-energy barrier that requires the chaperoning activity of the viral nucleocapsid protein. In addition to the nucleotide complementarity to the PBS, several regions of tRNA Lys 3 have been described as interacting with the viral genomic RNA. Among these sequences, a sequence of the viral genome called PAS for “primer activation signal” was proposed to interact with the T-arm of tRNA Lys 3 , this interaction stimulating the initiation of reverse transcription. In this report, we investigate the formation of this additional interaction with NMR spectroscopy, using a simple system composed of the primer tRNA Lys 3 , the 18 nucleotides of the PBS, the PAS (8 nucleotides) encompassed or not in a hairpin structure, and the nucleocapsid protein. Our NMR study provides molecular evidence of the existence of this interaction and highlights the role of the nucleocapsid protein in promoting this additional RNA-RNA annealing. This study presents the first direct observation at a single base-pair resolution of the PAS/anti-PAS association, which has been proposed to be involved in the chronological regulation of the reverse transcription.