An error-prone repair pathway that directly ligates broken DNA ends.
Ku70/80 bind broken ends, and DNA-PK, XRCC4 and ligase IV join them, often losing or adding a few bases. It works in all cell cycle phases and is the dominant repair route in mammalian cells.
Its error-proneness is used in CRISPR to disrupt genes.
An error-prone repair pathway that directly ligates broken DNA ends.
Non-Homologous End Joining is one of the 52 topics in Molecular Biology. It is rated Advanced, so it suits learners who want specialist depth. Related topics in this area include DNA Repair, Homologous Recombination, Nonsense-Mediated Decay.
V(D)J recombination in lymphocytes uses NHEJ, so defects cause immunodeficiency.
Work through the Beginner topics in Molecular Biology first, such as Central Dogma, DNA Replication, Base Pairing, then return to Non-Homologous End Joining. Advanced topics assume the Intermediate vocabulary.
The closest topics to Non-Homologous End Joining are DNA Repair, Homologous Recombination, Nonsense-Mediated Decay, Okazaki Fragments. Comparing them side by side is a good way to see how the ideas connect.
Read the summary and the in-depth section, then use the quick check on the interactive lesson for Non-Homologous End Joining. To practise the whole of Molecular Biology, use the Molecular Biology quiz.
Non-Homologous End Joining: An error-prone repair pathway that directly ligates broken DNA ends. DNA Repair: Mechanisms such as mismatch, excision and double-strand break repair that fix errors and damage in DNA. Read both side by side and note what each one explains.
First, read the summary and write the definition in your own words. Second, read the in-depth section and note any example. Third, compare it with DNA Repair and explain the difference aloud. Finally, take the Molecular Biology quiz and come back to this page for any question you miss.
Mechanisms such as mismatch, excision and double-strand break repair that fix errors and damage in DNA.
🧫 Molecular BiologyAn accurate repair pathway and meiotic mechanism exchanging DNA between similar sequences using RAD51.
🧫 Molecular BiologyA quality-control pathway that destroys mRNAs with premature stop codons.
🧫 Molecular BiologyShort DNA segments synthesised discontinuously on the lagging strand and joined by DNA ligase.
🧫 Molecular Biology