Journal
JOURNAL OF BIOLOGICAL CHEMISTRY
Volume 281, Issue 11, Pages 7421-7428Publisher
AMER SOC BIOCHEMISTRY MOLECULAR BIOLOGY INC
DOI: 10.1074/jbc.M511380200
Keywords
-
Categories
Funding
- NIAID NIH HHS [R37 AI030861, AI 30861] Funding Source: Medline
- NIGMS NIH HHS [T32 GM 07461] Funding Source: Medline
Ask authors/readers for more resources
Single-base deletions at nucleotide runs or - 1 frameshifting by human immunodeficiency virus type 1 (HIV-1) reverse transcriptase (RT) result from template slippage during polymerization. In crystal structures of HIV-1 RT complexed with DNA-DNA template-primer, the palm subdomain in the template cleft contacts the template backbone near the proposed site of slippage via the Glu(89) side chain. We investigated the role of Glu(89) in frameshifting by perturbing this interaction. Substitutions with Asp, Gly, Ala, Val, Ser, Thr, Asn, or Lys were created in recombinant HIV RT, and frameshift frequencies of the resulting mutant RTs were measured. All substitutions led to reduced -1 frameshifting by HIV-1 RT (2-40-fold). Interestingly, the suppression of -1 frameshifting frequently coincided with an enhancement of -1 frameshifting (3-47-fold) suggesting that Glu(89) can influence the slippage of both strands. Glu(89) substitutions also led to reduced rates of dNTP mis-incorporation that paralleled reductions in -1 frameshifting, suggesting a common structural mechanism for both classes of RT error. Our results reveal a major influence of Glu(89) on slippage-mediated errors and dNTP incorporation fidelity. The crystal structure of HIV-1 RT reveals a salt bridge between Glu(89) and Lys(154), which may facilitate -1 frameshifting; this concept is supported by the observed reduction in -1 frameshifting for K154A and K154R mutants.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available