Experimental Approaches to Investigate the Role of Helicase Acetylation in Regulating R-Loop Stability

  • Chenlin Song
  • Ingrid GrummtEmail author
Part of the Methods in Molecular Biology book series (MIMB, volume 1983)


R-loops are three-stranded nucleic acid structures composed of a DNA-RNA heteroduplex and a displaced single-stranded DNA. Although R-loops serve important roles in transcription and chromatin structure, they are also a major threat to genome stability. Cells prevent accumulation of genomic R-loops by mechanisms that remove these structures, such as ribonucleases which digest DNA-RNA hybrids and helicases which unwind R-loops. Here we describe methods to monitor resolvement of R-loops by the helicase DDX21 focussing on the impact of acetylation on helicase activity.


R-loops DNA-RNA hybrids Helicase DDX21 Recombinant proteins Immunopurification Protein acetylation Unwinding of DNA-RNA structures Gel electrophoresis 



Work in the Grummt lab is supported by the Deutsche Forschungsgemeinschaft (GR475/22-2 and SFB1036), CellNetworks (EcTop Survey 2014), and the Baden-Württemberg Stiftung.


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© Springer Science+Business Media, LLC, part of Springer Nature 2019

Authors and Affiliations

  1. 1.Division of Molecular Biology of the Cell IIGerman Cancer Research Center (DKFZ), DKFZ-ZMBH AllianceHeidelbergGermany

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