Figure 2.

Outline of DNA damage-tolerance pathways as triggered by lesions that block the replicative DNA polymerase. There are two DNA damage-tolerance strategies: error-prone translesion synthesis (the topic of the present review) and error-free damage avoidance (DA). DA pathways are still poorly defined and involve either gap filling by homologous recombination or fork regression. If all DNA damage strategies fail, it is likely that the fork collapses leading to gross genetic rearrangements or to cell death.