EC Explorer

3.1.21.2

deoxyribonuclease IV

Endonucleolytic cleavage of ssDNA at apurinic/apyrimidinic sites to 5′-phosphooligonucleotide end-products

deoxyribonuclease IV (phage-T₄-induced) (misleading), endodeoxyribonuclease IV (phage T₄-induced) (misleading), E. coli endonuclease IV, endodeoxyribonuclease (misleading), redoxyendonuclease, deoxriboendonuclease (misleading), endonuclease II, endonuclease IV, DNA-adenine-transferase, nfo (gene name)

63363-78-0

The enzyme is an apurinic/apyrimidinic (AP) site endonuclease that primes DNA repair synthesis at AP sites. It specifically cleaves the DNA backbone at AP sites and also removes 3′ DNA-blocking groups such as 3′ phosphates, 3′ phosphoglycolates, and 3′ α,β-unsaturated aldehydes that arise from oxidative base damage and the activity of combined glycosylase/lyase enzymes. It is also the only known repair enzyme that is able to cleave the DNA backbone 5′ of the oxidative lesion α-deoxyadenosine. The enzyme has a strong preference for single-stranded DNA.

created 1972 as EC 3.1.4.30, transferred 1978 to EC 3.1.21.2, modified 2014