The m6A methylation perturbs the Hoogsteen pairing-guided incorporation of an oxidized nucleotide† †Electronic supplementary information (ESI) available. See DOI: 10.1039/c7sc02340e Click here for additional data file.
نویسندگان
چکیده
Natural nucleic acid bases can formWatson–Crick (WC) or Hoogsteen (HG) base pairs. Importantly, 8-oxo20-deoxyguanosine (8-oxo-dG) in DNA or 8-oxo-dG 50-triphosphate (8-oxo-dGTP) favors a syn conformation because of the steric repulsion between O8 and O40 of the deoxyribose ring. 8-oxo-dGTP can be incorporated into DNA opposite the templating adenine (A) using HG pairing as the dominant mechanism. Both RNA and DNA can be methylated at the N6 position of A to form N-methyladenine (mA). It has been found that certain viral infections may trigger an increase in the production of both 8oxo-dGTP and mA. The current study aims to systematically explore the effects of mA methylation on HG base pairs and the consequent nucleotide incorporation. Our thermodynamic melting study shows that the mA$8-oxo-dG is significantly less stable than the A$8-oxo-dG base pair in the paired region of a DNA duplex. Moreover, we have used pre-steady-state kinetics to examine the incorporation of 8oxo-dGTP opposite mA relative to A by a variety of reverse transcriptase (RT) enzymes and DNA polymerase (DNA pol) enzymes such as the human immunodeficiency virus type 1 (HIV-1) RT and human DNA pol b. The results demonstrate that all of these enzymes incorporate 8-oxo-dGTP less efficiently opposite mA relative to A. Considering the steric bulk of the purine–purine pair between 8-oxo-dG and A, mA methylation may affect the HG pairing to a great extent. Hence, it will be unfavorable to incorporate 8-oxo-dGTP into the growing strand opposite mA. Moreover, the impeded incorporation of 8-oxo-dGTP opposite mA has been extended to determine mA at pre-defined positions in human rRNA. Our study may provide new insights into the roles of mA in reducing the mutagenic potential of cellular 8-oxo-dGTP.
منابع مشابه
Transformable H-bonds and conformation in compressed glucose† †Electronic supplementary information (ESI) available: Detailed experimental data; detailed structural data. CCDC 1033994–1034008. For ESI and crystallographic data in CIF or other electronic format see DOI: 10.1039/c4sc03588g Click here for additional data file. Click here for additional data file. Click here for additional data file. Click here for additional data file.
متن کامل
Enantioselective dearomatization of isoquinolines by anion-binding catalysis en route to cyclic α-aminophosphonates† †Electronic supplementary information (ESI) available: Experimental details, characterization and analytical data. CCDC 1476699 (4w). For ESI and crystallographic data in CIF or other electronic format see DOI: 10.1039/c6sc02466a Click here for additional data file. Click here for additional data file.
متن کامل
Photoinduced single-crystal-to-single-crystal phase transition and photosalient effect of a gold(i) isocyanide complex with shortening of intermolecular aurophilic bonds† †Electronic supplementary information (ESI) available: X-ray crystallographic data, optical properties, DFT calculations, and other additional information. CCDC [987280 and 987281]. For ESI and crystallographic data in CIF or other electronic format see DOI: 10.1039/c4sc02676d Click here for additional data file. Click here for additional data file. Click here for additional data file. Click here for additional data file. Click here for additional data file.
متن کامل
Coordination polymers of 5-substituted isophthalic acid† †Electronic supplementary information (ESI) available. CCDC 1417516–1417520 contain the supplementary crystallographic data for this paper. For ESI and crystallographic data in CIF or other electronic format see DOI: 10.1039/c5ce02091c Click here for additional data file. Click here for additional data file.
متن کامل
ذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
دوره 8 شماره
صفحات -
تاریخ انتشار 2017