标题：Mutations in the RNase H domain of HIV-1 reverse transcriptase affect the initiation of DNA synthesis and the specificity of RNase H cleavage in vivo
期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：2002
卷号：99
期号：14
页码：9515-9520
DOI：10.1073/pnas.142123199
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：Retroviral reverse transcriptases contain a DNA polymerase activity that can copy an RNA or DNA template and an RNase H activity that degrades the viral RNA genome during reverse transcription. RNase H makes both specific and nonspecific cleavages; specific cleavages are used to generate and remove the polypurine tract primer used for plus-strand DNA synthesis and to remove the tRNA primer used for minus-strand DNA synthesis. We generated mutations in an HIV-1-based vector to change amino acids in the RNase H domain that contact either the RNA and DNA strands. Some of these mutations affected the initiation of DNA synthesis, demonstrating an interdependence of the polymerase and RNase H activities of HIV-1 reverse transcription during viral DNA synthesis. The ends of the linear DNA form of the HIV-1 genome are defined by the specific RNase H cleavages that remove the plus- and minus-strand primers; these ends can be joined to form two-long-terminal repeat circles. Analysis of two-long-terminal repeat circle junctions showed that mutations in the RNase H domain affect the specificity of RNase H cleavage.
