Nature Structural & Molecular Biology
11, 435 - 442 (2004)
Published online: 18 April 2004; | doi:10.1038/nsmb758
Single-strand specificity of APOBEC3G accounts for minus-strand deamination of the HIV genomeQin Yu1, Renate König1, Satish Pillai2, Kristopher Chiles1, Mary Kearney3, Sarah Palmer3, Douglas Richman4, 5, John M Coffin3
& Nathaniel R Landau11
Infectious Disease Laboratory, The Salk Institute for Biological Studies, 10010 North Torrey Pines Road, La Jolla, California
92037, USA. 2
Division of Biological Sciences, University of California, San Diego, La Jolla, California
92093-0679, USA. 3
HIV Drug Resistance Program, National Cancer Institute, National Institutes of Health, Frederick, Maryland
21702, USA. 4
Departments of Pathology and Medicine, University of California, San Diego, La Jolla, California
92093-0679, USA. 5
Veterans Administration, San Diego Healthcare System, San Diego, California
92161, USA.
Correspondence should be addressed to Nathaniel R Landau landau@salk.eduHIV-1 deleted for the vif accessory gene encapsidates the cellular cytidine deaminase APOBEC3G. Upon infection, the encapsidated APOBEC3G induces G A mutations in the viral reverse transcripts. The G A mutations result either from C U deamination of the minus strand or deamination of both strands followed by repair of the plus strand. We report here that minus-strand deamination occurred over the length of the virus genome, preferentially at CCCA sequences, with a graded frequency in the 5' 3' direction. APOBEC3G induced previously undetected C T mutations in the 5' U3 and the primer-binding site, both of which become transiently single-stranded during reverse transcription. In vitro, APOBEC3G bound and deaminated single-stranded DNA (ssDNA) but not double-stranded DNA (dsDNA) or DNA-RNA hybrids. We propose that the requirement for ssDNA accounts for the minus-strand mutations, the 5' 3' graded frequency of deamination and the rare C T mutations.
MORE ARTICLES LIKE THIS These links to content published by NPG are automatically generated.
|