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DHX9/RHA Binding to the PBS-Segment of the Genomic RNA during HIV-1 Assembly Bolsters Virion Infectivity.

ABSTRACT: Cellular RNA-binding proteins incorporated into virions during human immunodeficiency virus type 1 (HIV-1) assembly promote the replication efficiency of progeny virions. Despite its critical role in bolstering virion infectivity, the molecular basis for the incorporation of DHX9/RNA helicase A (RHA) to virions remains unclear. Here, cell-based experiments demonstrate that the truncation of segments of the HIV-1 5'-untranslated region (5'-UTR) distinct from the core encapsidation sequence eliminated virion incorporation of RHA, indicating that RHA recruitment is mediated by specific interactions with the HIV-1 5'-UTR. In agreement with biological data, isothermal titration calorimetry determined that the dimer conformation of the 5'-UTR binds one RHA molecule per RNA strand, and the interaction is independent of nucleocapsid protein binding. NMR spectra employing a deuterium-labeling approach enabled resolution of the dimeric 5'-UTR in complex with the RHA N-terminal domain. The structure of the large molecular mass complex was dependent on RHA binding to a double-stranded region of the primer binding site (PBS)-segment of the 5'-UTR. A single A-to-C substitution was sufficient to disrupt biophysical conformation and attenuate virion infectivity in cell-based assays. Taken together, our studies demonstrate the structural basis for HIV-1 genomic RNA to recruit beneficial cellular cofactor to virions. The support of progeny virion infectivity by RHA is attributable to structure-dependent binding at the PBS-segment of the HIV-1 5'-UTR during virus assembly.

SUBMITTER: Boeras I

PROVIDER: S-EPMC4884555 | biostudies-literature | 2016 Jun

REPOSITORIES: biostudies-literature

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DHX9/RHA Binding to the PBS-Segment of the Genomic RNA during HIV-1 Assembly Bolsters Virion Infectivity.

Boeras Ioana I Song Zhenwei Z Moran Andrew A Franklin Jarryd J Brown William Clay WC Johnson Marc M Boris-Lawrie Kathleen K Heng Xiao X

Journal of molecular biology 20160421 11

Cellular RNA-binding proteins incorporated into virions during human immunodeficiency virus type 1 (HIV-1) assembly promote the replication efficiency of progeny virions. Despite its critical role in bolstering virion infectivity, the molecular basis for the incorporation of DHX9/RNA helicase A (RHA) to virions remains unclear. Here, cell-based experiments demonstrate that the truncation of segments of the HIV-1 5'-untranslated region (5'-UTR) distinct from the core encapsidation sequence elimin ...[more]

PMID: 27107641

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Dataset Information

DHX9/RHA Binding to the PBS-Segment of the Genomic RNA during HIV-1 Assembly Bolsters Virion Infectivity.

Publications

DHX9/RHA Binding to the PBS-Segment of the Genomic RNA during HIV-1 Assembly Bolsters Virion Infectivity.

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