A Molecular Mechanism Deciphered (IMAGE) University of Konstanz Caption A molecular mechanism deciphered: Once activated, e.g. through DNA damage, the enzyme PARP-1 forms the biopolymer PAR (poly(ADP-ribose)). PAR, in turn, initiates binding to the tumour-suppressor protein p53 in the region of the C-terminal domain (CTD). PARP-1 will then modify p53 with the PAR biopolymer. As depicted in the lower part of the picture, these molecular processes have far-reaching implications for a number of biochemical and cellular functions that play an important role in tumour biology. Credit Aswin Mangerich, University of Konstanz Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.