Poly ADP Ribose Transferase (PARP) is an enzyme that plays a crucial role in several cellular processes, particularly in the regulation of DNA repair and cell death. It catalyzes the transfer of ADP-ribose units from nicotinamide adenine dinucleotide (NAD+) to various protein acceptors, thereby causing post-translational modifications.
PARP is primarily associated with the repair of single-stranded DNA breaks (SSBs). Upon detection of such breaks, PARP is rapidly activated and binds to the damaged DNA, facilitating the recruitment of repair proteins to the site of injury. By attaching ADP-ribose units to these proteins, PARP helps to promote their proper functioning and coordination, ultimately repairing the DNA damage.
Additionally, PARP is involved in cellular processes such as chromatin remodeling, transcriptional regulation, and cell death pathways. In cases where DNA damage is extensive and irreparable, PARP can initiate programmed cell death by consuming large amounts of NAD+ and ATP, leading to cellular energy depletion and activation of apoptosis.
PARP has attracted significant interest in the field of cancer research due to its vital role in DNA repair. Inhibitors of PARP have been developed as potential therapeutic agents for various cancers, including those with defects in DNA repair mechanisms such as BRCA-mutated tumors.
Overall, PARP is an essential enzyme that contributes to the maintenance of genome stability, cell survival, and regulation of various cellular processes.
