Fig. 2: ATRX RNA binding activity inhibits R-loop formation.

a DNA strand displacement assay with full-length ATRX (25 nM) and 1 nM DNA triplex substrates with or without ATP as indicated. Positions of duplex and DNA triplex are shown. For all subsequent panels in this figure, quantification of 3 independent experiments is shown as mean values ± SEM. p, two-sided Student’s t-test. b R-loop resolution assay with full-length ATRX (25 nM) and 1 nM R-loop substrates with or without ATP as indicated. Positions of duplex and R-loops are shown. c R-loop resolution assay with 25 nM DDX5 and 1 nM R-loop substrates without or with ATP as indicated. d D-loop resolution assay with full-length ATRX (25 nM) and 1 nM D-loop substrates with or without ATP as indicated. Positions of duplex and D-loops are shown. e R-loop formation assay with 1.25 nM DNA duplex, 3.75 nM RNA and increasing concentrations of full-length ATRX (5, 25, 125 nM). f D-loop formation assay 1.25 nM DNA duplex, 3.75 nM ssDNA and increasing concentrations of full-length ATRX (5, 25, 125 nM). g R-loop formation assay with 1.25 nM DNA duplex, 3.75 nM RNA, and increasing concentrations of full-length SLBP (5, 25, 125 nM). h R-loop formation assay with 1.25 nM DNA duplex, 3.75 nM RNA, and increasing concentrations of ATRXΔRBR (5, 25, 125 nM). i Model: ATRX interacts with repeat containing RNAs through its RNA binding region and prevents their incorporation into R-loops. ATRX deletion allows RNAs to hybridize to their complementary DNA, resulting in R-loop stabilization and accumulation. Source data underlying (a–h) are provided as a Source data file.