Removal of 3'-phosphoglycolate (PG) moiety from DSB ends

Stable Identifier
Reaction [transition]
Gallus gallus
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Before rejoining of the broken DNA ends can occur, endonucleases removes possible 3' phospho-glycolate residues so that a DNA-PK synaptic complex with ligatable DNA is formed at the DSB. Rejoining of ionizing radiation (IR)-induced DNA DSBs usually follows biphasic kinetics with a fast (t(1/2): 5-30 min) component attributed to DNA PK dependent non homologous end joining (NHEJ) and a slow (t(1/2): 1-20 h) component of as yet uncharacterized reaction. In a systematic genetic study using the chicken DT40 cell line and employing a series of mutants defective in homologous recombination (HR), it was suggested that NHEJ is the main pathway for rejoining of IR-induced DNA DSBs in vertebrates. It is speculated that the contribution of homologous recombination repair (HRR) occurs at a stage after the initial rejoining.

Literature References
PubMed ID Title Journal Year
11402316 Efficient rejoining of radiation-induced DNA double-strand breaks in vertebrate cells deficient in genes of the RAD52 epistasis group

Wang, H, Zeng, ZC, Bui, TA, Sonoda, E, Takata, M, Takeda, S, Iliakis, G

Oncogene 2001
Participant Of
Catalyst Activity
Catalyst Activity
endonuclease activity of TDP1 [nucleoplasm]
Physical Entity