title: Nanoscale Characterization of Interaction of APOBEC3G with RNA.
abstract: The human cytidine deaminase APOBEC3G (A3G) is a potent inhibitor of the HIV-1 virus in the absence of viral infectivity factor (Vif). The molecular mechanism of A3G antiviral activity is primarily attributed to deamination of single-stranded DNA (ssDNA); however, the nondeamination mechanism also contributes to HIV-1 restriction. The interaction of A3G with ssDNA and RNA is required for its antiviral activity. Here we used atomic force microscopy to directly visualize A3G-RNA and A3G-ssDNA complexes and compare them to each other. Our results showed that A3G in A3G-RNA complexes exists primarily in monomeric-dimeric states, similar to its stoichiometry in complexes with ssDNA. New A3G-RNA complexes in which A3G binds to two RNA molecules were identified. These data suggest the existence of two separate RNA binding sites on A3G. Such complexes were not observed with ssDNA substrates. Time-lapse high-speed atomic force microscopy was applied to characterize the dynamics of the complexes. The data revealed that the two RNA binding sites have different affinities for A3G. On the basis of the obtained results, a model for the interaction of A3G with RNA is proposed.
authors.affiliation: Department of Pharmaceutical Sciences, College of Pharmacy, WSH, University of Nebraska Medical Center , 986025 Nebraska Medical Center, Omaha, Nebraska 68198-6025, United States.
authors.forename: Yangang
authors.initials: Y
authors.lastname: Pan
authors.affiliation: Department of Pharmaceutical Sciences, College of Pharmacy, WSH, University of Nebraska Medical Center , 986025 Nebraska Medical Center, Omaha, Nebraska 68198-6025, United States.
authors.forename: Zhiqiang
authors.initials: Z
authors.lastname: Sun
authors.affiliation: Frederick National Laboratory for Cancer Research, Leidos Biomedical Research, Inc. , Advanced Technology Research Facility, 8560 Progress Drive, Frederick, Maryland 21702, United States.
authors.forename: Atanu
authors.initials: A
authors.lastname: Maiti
authors.affiliation: Frederick National Laboratory for Cancer Research, Leidos Biomedical Research, Inc. , Advanced Technology Research Facility, 8560 Progress Drive, Frederick, Maryland 21702, United States.
authors.forename: Tapan
authors.initials: T
authors.lastname: Kanai
authors.affiliation: Frederick National Laboratory for Cancer Research, Leidos Biomedical Research, Inc. , Advanced Technology Research Facility, 8560 Progress Drive, Frederick, Maryland 21702, United States.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Matsuo
authors.affiliation: Department of Biochemistry, Molecular Biology and Biophysics, Institute for Molecular Virology, Center for Genome Engineering, Masonic Cancer Center, University of Minnesota , Minneapolis, Minnesota 55455, United States.
authors.forename: Ming
authors.initials: M
authors.lastname: Li
authors.affiliation: Department of Biochemistry, Molecular Biology and Biophysics, Institute for Molecular Virology, Center for Genome Engineering, Masonic Cancer Center, University of Minnesota , Minneapolis, Minnesota 55455, United States.|Howard Hughes Medical Institute, University of Minnesota , Minneapolis, Minnesota 55455, United States.
authors.forename: Reuben S
authors.initials: RS
authors.lastname: Harris
authors.affiliation: Department of Pharmaceutical Sciences, College of Pharmacy, WSH, University of Nebraska Medical Center , 986025 Nebraska Medical Center, Omaha, Nebraska 68198-6025, United States.
authors.forename: Luda S
authors.initials: LS
authors.lastname: Shlyakhtenko
authors.affiliation: Department of Pharmaceutical Sciences, College of Pharmacy, WSH, University of Nebraska Medical Center , 986025 Nebraska Medical Center, Omaha, Nebraska 68198-6025, United States.
authors.forename: Yuri L
authors.initials: YL
authors.lastname: Lyubchenko
mesh_terms: D000071480:APOBEC-3G Deaminase / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D001665:Binding Sites; D003001:Cloning, Molecular; D004277:DNA, Single-Stranded / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D004279:DNA, Viral / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism; D015870:Gene Expression; D054884:Host-Pathogen Interactions; D006801:Humans; D018625:Microscopy, Atomic Force; D011485:Protein Binding; D000072417:Protein Domains; D012367:RNA, Viral / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism
chemical_list: D004277:DNA, Single-Stranded; D004279:DNA, Viral; D012367:RNA, Viral; D011994:Recombinant Proteins; D000071480:APOBEC-3G Deaminase; C464924:APOBEC3G protein, human