Structural Basis for DNA Damage–Dependent Poly(ADP-ribosyl)ation by Human PARP-1

+ See all authors and affiliations

Science  11 May 2012:
Vol. 336, Issue 6082, pp. 728-732
DOI: 10.1126/science.1216338

You are currently viewing the abstract.

View Full Text


Poly(ADP-ribose) polymerase–1 (PARP-1) (ADP, adenosine diphosphate) has a modular domain architecture that couples DNA damage detection to poly(ADP-ribosyl)ation activity through a poorly understood mechanism. Here, we report the crystal structure of a DNA double-strand break in complex with human PARP-1 domains essential for activation (Zn1, Zn3, WGR-CAT). PARP-1 engages DNA as a monomer, and the interaction with DNA damage organizes PARP-1 domains into a collapsed conformation that can explain the strong preference for automodification. The Zn1, Zn3, and WGR domains collectively bind to DNA, forming a network of interdomain contacts that links the DNA damage interface to the catalytic domain (CAT). The DNA damage–induced conformation of PARP-1 results in structural distortions that destabilize the CAT. Our results suggest that an increase in CAT protein dynamics underlies the DNA-dependent activation mechanism of PARP-1.

View Full Text