NU 7026, DNA-PK inhibitor

Supplementary information

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

DNA-dependent protein kinase catalytic subunit often abbreviated as DNA-PKcs or PKcs is an important component in the cellular machinery responsible for DNA repair. This protein weighs approximately 470 kDa and is predominantly expressed in various tissue types with higher levels found in lymphoid tissues. The DNA-PKcs functions as a serine/threonine protein kinase and becomes active upon binding to DNA contributing to its role in maintaining genome integrity.

Biological function summary

DNA-PKcs plays an essential role in the non-homologous end joining (NHEJ) repair pathway which repairs double-strand breaks in DNA. DNA-PKcs forms a complex with the Ku70/80 heterodimer serving as a critical component of the DNA repair mechanism. This complex recognizes DNA ends facilitates their synapsis and activates other enzymes involved in ligating the broken DNA strands therefore promoting cellular survival following DNA damage.

Pathways

DNA-PKcs deeply integrates into the DNA damage response pathway. It collaborates closely with proteins such as ATM (ataxia-telangiectasia mutated) to sense DNA damage and initiate repair. DNA-PKcs is involved in V(D)J recombination vital for the generation of diverse antibodies in immune cells. Its activity is essential for coordinating with other proteins including XRCC4 and Ligase IV to ensure efficient DNA repair processes are executed.

Defects in DNA-PKcs are linked to severe combined immunodeficiency (SCID) due to its central role in V(D)J recombination. Dysfunction in its pathway also relates to cancer where impaired DNA repair mechanisms substantially increase genomic instability leading to tumorigenesis. DNA-PKcs interacts with other proteins like BRCA1 and p53 in tumors where its overexpression or mutations can contribute to resistance against radiation and chemotherapeutic agents. These interactions highlight the importance of DNA-PK inhibitors as potential therapeutic strategies in oncology.