Background

DNA-dependent protein kinase (DNA-PK) is a serine/threonine kinase that plays a critical role in repairing DNA double-strand breaks through the non-homologous end joining (NHEJ) pathway. Following DNA damage, DNA-PK helps coordinate repair processes essential for maintaining genomic stability and cell survival. Dysregulation of DNA-PK activity has been linked to cancer progression and resistance to radiation and chemotherapy, making it an important target for oncology research.

DNA-PK functions within the broader DNA damage response (DDR) network, alongside ATM and ATR, to regulate DNA repair and cellular responses to genotoxic stress. The Eurofins DiscoverX DNA-PK Kinase Enzyme Activity Assay Kit (#44-950) provides a convenient biochemical assay for measuring DNA-PK activity in enzyme characterization, inhibitor profiling, and screening applications.

Product Highlights
  • Specifically developed for DNA-PK kinase activity measurement
  • Simple ADP accumulation assay with a DNA-PK-specific peptide substrate
  • Suitable for evaluation of DNA-PK inhibitors and pathway modulators
  • Supports DDR, genome stability, and DNA repair research
  • Applicable to drug discovery, lead optimization, and kinase profiling studies

DNA-PK Kinase Enzyme Activity Assay Kit Assay Principle

The DNA-PK Kinase Enzyme Activity Assay Kit measures DNA-PK activity by quantifying ADP generated during a kinase reaction. In the presence of ATP, the kinase phosphorylates the DNA-PK-specific peptide substrate (EK-15), converting ATP to ADP. Following the kinase reaction, ADP is detected using ADP Hunter™ technology, in which ADP is enzymatically converted through a series of coupled reactions to generate hydrogen peroxide. Hydrogen peroxide subsequently reacts with a fluorogenic substrate to produce resorufin, generating a fluorescent signal proportional to DNA-PK activity. The red-shifted fluorescence of resorufin minimizes interference from compound autofluorescence and other assay components, improving assay robustness for inhibitor profiling and screening applications. The homogeneous format enables sensitive and quantitative measurement of DNA-PK activity.

DNA-PK Kinase Enzyme Activity Assay Assay Principle