ADP-ribosylation signaling orchestrates the recruitment of various repair actors and
chromatin remodeling processes promoting access to lesions during the early stages
of the DNA damage response. The chromatin remodeler complex ACF, composed of the ATPase
subunit SMARCA5/SNF2H and the cofactor ACF1/BAZ1A, is among the factors that accumulate
at DNA lesions in an ADP-ribosylation dependent manner. In this work, we show that
each subunit of the ACF complex accumulates to DNA breaks independently from its partner.
Furthermore, we demonstrate that the recruitment of SMARCA5 and ACF1 to sites of damage
is not due to direct binding to the ADP-ribose moieties but due to facilitated DNA
binding at relaxed ADP-ribosylated chromatin. Therefore, our work provides new insights
regarding the mechanisms underlying the timely accumulation of ACF1 and SMARCA5 to
DNA lesions, where they contribute to efficient DNA damage resolution.
