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 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.
