DNA postreplication repair gap filling in temperature-sensitive dnaG, dnaC, dnaA mutants of Escherichiacoli

Gaps in daughter-strand deoxyribonucleic acid (DNA) synthesized after exposure of wild-type $\text{Escherichia}\text{coli}$ to ultraviolet light are filled during reincubation. In this study the $\text{dnaG}\text{,}\text{dnaC}$, and $\text{dnaA}$ gene products have been examined for their role in postreplication repair. These gene products are unique in their specific control of certain types of DNA synthesis: initiation of rounds of replication and chain propagation. Initiation of rounds of replication is not essential to gap filling; however, chain propagation by short DNA piece initiation appears to be essential for gap filling.