Figure 7.

Model representing the regulating roles of histone transfer pathways on the usage of error-free versus error-prone pathways of DNA damage tolerance. (Top) Schematics showing that Dpb3–Dpb4 and Mcm2–Ctf4–Polα facilitate parental (H3–H4)₂ transfer to the leading and lagging strands of the replication fork. (Bottom) In WT cells, error-free and error-prone pathways are correctly balanced to favor error-free template switching and exclude TLS polymerases from the nascent strands. When Dbp3–Dpb4 and Mcm2–Ctf4–Polα pathways of parental histone transfer are defective, the error-free branch of DDT is impaired and TLS polymerases have increased access to the nascent strands, leading to increased mutagenesis and drug resistance.