Fig. 1: smFRET assay for probing the DNA conformation in presence of PARP-1.
From: Structural dynamics of DNA strand break sensing by PARP-1 at a single-molecule level
a Domain architecture of full-length PARP-1 and PARP-1 fragments F2 and F1F2. Domains are abbreviated as: F1, F2, F3: zinc finger domains; BRCT: breast cancer susceptibility protein C-terminal domain; WGR: WGR domain; HD: α-helical subdomain; ART: ADP-ribosyl transferase subdomain. b Schematic displaying the sequence and predicted secondary structure of the DNA ligand used in this study. The DNA is labeled with Alexa647 (red) at position T18 and with ATTO 550 (blue) at position T37; both dyes are attached via a C2 linker (Methods). c smFRET efficiency histogram obtained from freely diffusing molecules of the nicked DNA (blue), DNA after highly efficienct ligation of the nick (grey, Supplementary Fig. 1), and of the nicked DNA in the presence of full-length PARP-1 (black). d Schematic depicting how changes in DNA conformation can be detected by smFRET.
