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Effect of tRNA on the Maturation of HIV-1 Reverse Transcriptase.

ABSTRACT: The mature HIV-1 reverse transcriptase is a heterodimer that comprises 66?kDa (p66) and 51?kDa (p51) subunits. The latter is formed by HIV-1 protease-catalyzed removal of a C-terminal ribonuclease H domain from a p66 subunit. This proteolytic processing is a critical step in virus maturation and essential for viral infectivity. Here, we report that tRNA significantly enhances in vitro processing even at a substoichiometric tRNA:p66/p66 ratio. Other double-stranded RNAs have considerably less pronounced effect. Our data support a model where interaction of p66/p66 with tRNA introduces conformational asymmetry in the two subunits, permitting specific proteolytic processing of one p66 to provide the mature RT p66/p51 heterodimer.

SUBMITTER: Ilina TV

PROVIDER: S-EPMC5988984 | biostudies-literature | 2018 Jun

REPOSITORIES: biostudies-literature

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Effect of tRNA on the Maturation of HIV-1 Reverse Transcriptase.

Ilina Tatiana V TV Slack Ryan L RL Elder John H JH Sarafianos Stefan G SG Parniak Michael A MA Ishima Rieko R

Journal of molecular biology 20180508 13

The mature HIV-1 reverse transcriptase is a heterodimer that comprises 66 kDa (p66) and 51 kDa (p51) subunits. The latter is formed by HIV-1 protease-catalyzed removal of a C-terminal ribonuclease H domain from a p66 subunit. This proteolytic processing is a critical step in virus maturation and essential for viral infectivity. Here, we report that tRNA significantly enhances in vitro processing even at a substoichiometric tRNA:p66/p66 ratio. Other double-stranded RNAs have considerably less pro ...[more]

PMID: 29751015

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