Reverse transcriptase and substrate dependence of the RNA hypermutagenesis reaction

Miguel Angel Martinez (1) , Monica Sala (1) , Jean Pierre Vartanian (1) , S Wain-Hobson (1) , Simon Wain-Hoboson (1)

1 Rétrovirologie Moléculaire

G-->A hypermutation is a remarkable phenomenon resulting from retroviral reverse transcription in the presence of highly biased dNTP concentrations. Of the three reverse transcriptases (RTases) available, those of human immunodeficiency virus type 1 (HIV-1), avian myeloblastosis virus (AMV) and Moloney murine leukemia virus (MoMLV), the HIV-1 enzyme showed the greatest sensitivity to biased [dCTP]/[dTTP] ratios. The HIV-1 RTase was able to discriminate between dUTP, dITP and the four DNA precursors and was insensitive to pH. There was little preference for nucleotide contexts. A few exceptionally modified sequences were found presumably resulting from G-->A hypermutation and multiple strand transfer. This particular predilection of the HIV-1 and, by extrapolation, the lentiviral RTases towards G-->A hypermutation suggests that the phenomenon may have contributed to the remarkably elevated A content of these retroviral genomes.

Domaines: Sciences du Vivant [q-bio]

Miguel Angel Martinez, Monica Sala, Jean Pierre Vartanian, S Wain-Hobson, Simon Wain-Hoboson. Reverse transcriptase and substrate dependence of the RNA hypermutagenesis reaction. Nucleic Acids Research, 1995, 23 (14), pp.2573-2578. ⟨10.1093/nar/23.14.2573⟩. ⟨pasteur-03520153⟩