The MutY protein is an adenine glycosylase that is specific for A residues opposite 8-oxoG residues. This allows repair that gives C another chance to be incorporated. Direct reversal by photolyase . Binds to pyrimidine dimers. Binding induces new absorption band in blue visible.
Absorbed photons photoreverse the dimer directly.
Only occurs in the light, thus called light repair . Three proteins acting together in a complex. UvrB and UvrC are endonucleases. The UvrB protein makes a nick 3 to 5 bases downstream of the lesion, on the strand containing the lesion. The UvrC protein makes a nick on the same strand about 7 bases to the 5' side of the lesion.