» Articles » PMID: 15004241

Using Pyrrolo-deoxycytosine to Probe RNA/DNA Hybrids Containing the Human Immunodeficiency Virus Type-1 3' Polypurine Tract

Overview
Specialty Biochemistry
Date 2004 Mar 9
PMID 15004241
Citations 38
Authors
Affiliations
Soon will be listed here.
Abstract

Recent structural analyses indicate that localized regions of abnormal base pairing exist within RNA/DNA hybrids containing the HIV-1 polypurine tract (PPT) and that these distortions may play a role in PPT function. To examine this directly, we have introduced pyrrolo-deoxycytosine (pdC), a fluorescent, environmentally sensitive analog of deoxycytosine (dC), into the DNA strand of PPT-containing hybrids. Steady-state fluorescence analysis of these hybrids reveals that the DNA base 11 nt from the PPT-U3 junction is unpaired even in the absence of reverse transcriptase (RT). Unstable base pairing is also observed within the (rG:dC)6 tract in the downstream portion of the duplex, suggesting that HIV-1 RT may recognize multiple pre-existing distortions during PPT selection. HIV-1 RT hydrolyzes pdC-containing hybrids primarily at the PPT-U3 junction, indicating that the analog does not induce a gross structural deformation of the duplex. However, aberrant cleavage is frequently observed 3 bp from the site of pdC substitution, most likely reflecting a specific interaction between the analog and amino acid residues within the RNase H primer grip. pdC substitution within the template strand of a DNA duplex does not appear to significantly affect RT-catalyzed DNA synthesis. Implications of these findings on the use of pdC to examine nucleic acid structure are discussed.

Citing Articles

Breaking the blue barrier of nucleobase fluorescence emission with dicyanovinyl-based uracil molecular rotor probes.

Chowdhury M, John A, Hudson R RSC Adv. 2024; 14(50):37605-37609.

PMID: 39588240 PMC: 11586925. DOI: 10.1039/d4ra07000c.


High fidelity DNA strand-separation is the major specificity determinant in DNA methyltransferase CcrM's catalytic mechanism.

Konttinen O, Carmody J, Kurnik M, Johnson K, Reich N Nucleic Acids Res. 2023; 51(13):6883-6898.

PMID: 37326016 PMC: 10359602. DOI: 10.1093/nar/gkad443.


6-phenylpyrrolocytosine as a fluorescent probe to examine nucleotide flipping catalyzed by a DNA repair protein.

Kotandeniya D, Rogers M, Fernandez J, Kanugula S, Hudson R, Rodriguez F Biopolymers. 2020; 112(1):e23405.

PMID: 33098572 PMC: 7856187. DOI: 10.1002/bip.23405.


Cell cycle regulated DNA methyltransferase: fluorescent tracking of a DNA strand-separation mechanism and identification of the responsible protein motif.

Konttinen O, Carmody J, Pathuri S, Anderson K, Zhou X, Reich N Nucleic Acids Res. 2020; 48(20):11589-11601.

PMID: 33053173 PMC: 7672430. DOI: 10.1093/nar/gkaa844.


Mechanism of polypurine tract primer generation by HIV-1 reverse transcriptase.

Figiel M, Krepl M, Park S, Poznanski J, Skowronek K, Golab A J Biol Chem. 2017; 293(1):191-202.

PMID: 29122886 PMC: 5766924. DOI: 10.1074/jbc.M117.798256.


References
1.
Rausch J, Qu J, Yi-Brunozzi H, Kool E, Le Grice S . Hydrolysis of RNA/DNA hybrids containing nonpolar pyrimidine isosteres defines regions essential for HIV type 1 polypurine tract selection. Proc Natl Acad Sci U S A. 2003; 100(20):11279-84. PMC: 208748. DOI: 10.1073/pnas.1932546100. View

2.
Lener D, Kvaratskhelia M, Le Grice S . Nonpolar thymine isosteres in the Ty3 polypurine tract DNA template modulate processing and provide a model for its recognition by Ty3 reverse transcriptase. J Biol Chem. 2003; 278(29):26526-32. DOI: 10.1074/jbc.M302374200. View

3.
Wohrl B, Moelling K . Interaction of HIV-1 ribonuclease H with polypurine tract containing RNA-DNA hybrids. Biochemistry. 1990; 29(44):10141-7. DOI: 10.1021/bi00496a001. View

4.
Clark Jr A, Williams R, Nanni R, Clark P, Ferris A, Hughes S . Crystals of a ternary complex of human immunodeficiency virus type 1 reverse transcriptase with a monoclonal antibody Fab fragment and double-stranded DNA diffract x-rays to 3.5-A resolution. Proc Natl Acad Sci U S A. 1991; 88(23):10895-9. PMC: 53038. DOI: 10.1073/pnas.88.23.10895. View

5.
Charneau P, Alizon M, Clavel F . A second origin of DNA plus-strand synthesis is required for optimal human immunodeficiency virus replication. J Virol. 1992; 66(5):2814-20. PMC: 241038. DOI: 10.1128/JVI.66.5.2814-2820.1992. View