Figure 4.

DNA Damage Arising in Absence of BRCA1/SETX Complexes at Termination Pause Sites Is R-Loop Dependent

(A and B) BRCA1 (A) and SETX (B) ChIP analyses performed on the ENSA and Akirin1 genes in HeLa cells transfected with siCt, siBRCA1, or siSETX. ENSA and Akirin1 transcription termination is regulated by R-loops and CoTC sequences, respectively. Intronic regions (Intr) were studied as controls. Average ChIP values ± SD from three independent experiments are shown.

(C) γH2AX ChIP experiments performed as in (A) and analyzed as in Figure 3A. Average ChIP values ± SD from three independent experiments are shown.

(D) Representative pictures of comet assays performed under alkaline conditions in HeLa cells transfected with siCt, siBRCA1, or siSETX in the absence (−RNaseH1) and presence (+RNaseH1) of ectopic RNaseH1 expression.

(E) Quantitative analysis of comet tail lengths for each condition showed in (D). Average tail lengths ±SEM from three independent experiments are shown. ^∗∗∗p < 0.001 by two-tailed Student’s t test.

See also Figure S4.