1,5-Isoquinolinediol, PARP-1 inhibitor

Supplementary information

This supplementary information is collated from multiple sources and compiled automatically.

PARP1 also known as poly(ADP-ribose) polymerase 1 is an enzyme that plays an important role in DNA repair processes. It detects DNA single-strand breaks and uses NAD+ as a substrate to add ADP-ribose polymers to itself and other proteins. This post-translational modification signals DNA repair machinery to the site of damage. PARP1 has a molecular weight of approximately 116 kDa. It is widely expressed in the nucleus of eukaryotic cells. PARP1 is often studied by western blotting techniques to analyze its expression and activation levels.

Biological function summary

Poly(ADP-ribose) polymerase 1 functions to maintain genomic stability by acting within the base excision repair complex. This complex is important for the detection and repair of DNA damage preventing the accumulation of mutations. By acting at sites of DNA stress PARP1 facilitates the binding of DNA repair proteins stabilizing the DNA structure during the repair process. This role is significant for cells that undergo frequent DNA replication or are exposed to high levels of genotoxic stress.

Pathways

The PARP1 protein is integral to the DNA damage response and repair pathway. It interacts with other proteins such as XRCC1 to coordinate repair activities at damaged DNA sites. Another important pathway involving PARP1 is the apoptosis pathway where excessive activation of PARP1 can lead to cell death due to depletion of cellular NAD+ and ATP. This indicates its dual role in both promoting cell survival through DNA repair and contributing to cell death when damage is irreparable.

Poly(ADP-ribose) polymerase 1 is strongly linked to cancer and neurodegenerative diseases. Its activity is heightened in many cancer types where cancer cells exploit PARP1 for survival by repairing DNA damage that would otherwise be lethal. Inhibitors of PARP1 are being developed as cancer therapies to target these survival mechanisms. Moreover overactivation of PARP1 in neurodegenerative disorders like Alzheimer's disease can lead to excessive energy consumption promoting neuronal cell damage. In these contexts PARP1 connects with proteins like BRCA1 in cancer or AIF in neurodegeneration illustrating its role in disease mechanisms.