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

• Authors: Tatiana V. Ilina, University of Pittsburgh; Ryan L. Slack, University of Pittsburgh; John H. Elder, Scripps Research Institute; Stefan Sarafianos, Emory University; Michael A. Parniak, University of Pittsburgh; Rieko Ishima, University of Pittsburgh
• Journal Title: Journal of Molecular Biology
• Volume: Volume 430, Number 13
• Publisher: Elsevier | 2018-06-22, Pages 1891-1900
• Type of Work: Article | Post-print: After Peer Review
• Publisher DOI: http://doi.org/10.1016/j.jmb.2018.02.027
• Subjects: Biology, Molecular; Chemistry, Biochemistry; Health Sciences, Public Health
• Keywords: Science & Technology; Life Sciences & Biomedicine; Biochemistry & Molecular Biology; HIV-1; proteolysis; maturation; tRNA; reverse transcriptase; RNase H; IMMUNODEFICIENCY-VIRUS TYPE-1; POL POLYPROTEIN PRECURSOR; TRYPTOPHAN REPEAT MOTIF; RIBONUCLEASE-H DOMAIN; ANGSTROM RESOLUTION; CRYSTAL-STRUCTURE; IN-VITRO; GAG-POL; PROTEASE INHIBITORS; HOMODIMER FORMATION

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.