Figure 5.

Nucleotide excision repair patterns for prokaryotes, archaea, and eukaryotes. In the two prokaryotes, E. coli and M. smegmatis, dual incisions occur 7 nt 5´ and 3–4 nt 3´ to the UV photoproduct, resulting in excision products predominantly 12–13 nt in length. In the archaea, M. thermoautotrophicum, dual incisions occur 5–6 nt 5´ and 3–4 nt 3´ to the UV photoproduct, resulting in excision products predominantly 11 nt in length (8). In yeast cells, the photoproducts are excised by dual incisions 13–18 nt 5´ and 6–7 nt 3´ to the damage (28). In humans, plants, and insects, the dual-incision sites are at 19–22 nt 5´ and 5–6 nt 3´ to the UV damage (27, 29, 42). In eukaryotes there is considerable variability in incision sites, principally at the 5´ incision site, giving rise to excision products with a median length of 24 nt in S. cerevisiae and 26–27 nt in D. melanogaster, H. sapiens, and A. thaliana.