Revisiting Plus-Strand DNA Synthesis in Retroviruses and Long Terminal Repeat Retrotransposons: Dynamics of Enzyme: Substrate Interactions

Viruses

Daniele Fabris¹  John P. Marino² 

[1] Department of Chemistry and Biochemistry, University of Maryland Baltimore County, 1000 Hilltop Circle, Baltimore, MD 21228, USA;Center for Advanced Research in Biotechnology of the University of Maryland Biotechnology Institute and the National Institute of Standards and Technology, 9600 Gudelsky Drive, Rockville, MD 20850, USA

关键词: retroviruses;    LTR-retrotransposons;    polypurine tract;    plus strand DNA synthesis;    NMR spectroscopy;    single molecule spectroscopy;    antiviral strategies;   

DOI  :  10.3390/v1030657

来源: mdpi

【 摘 要 】

Although polypurine tract (PPT)-primed initiation of plus-strand DNA synthesis in retroviruses and LTR-containing retrotransposons can be accurately duplicated, the molecular details underlying this concerted series of events remain largely unknown. Importantly, the PPT 3’ terminus must be accommodated by ribonuclease H (RNase H) and DNA polymerase catalytic centers situated at either terminus of the cognate reverse transcriptase (RT), and in the case of the HIV-1 enzyme, ~70Å apart. Communication between RT and the RNA/DNA hybrid therefore appears necessary to promote these events. The crystal structure of the HIV-1 RT/PPT complex, while informative, positions the RNase H active site several bases pairs from the PPT/U3 junction, and thus provides limited information on cleavage specificity. To fill the gap between biochemical and crystallographic approaches, we review a multidisciplinary approach combining chemical probing, mass spectrometry, NMR spectroscopy and single molecule spectroscopy. Our studies also indicate that nonnucleoside RT inhibitors affect enzyme orientation, suggesting initiation of plus-strand DNA synthesis as a potential therapeutic target.

【 授权许可】

CC BY   
© 2009 by the authors; licensee Molecular Diversity Preservation International, Basel, Switzerland