Author: Zachary Joseph RomeroPublisher:
ISBN:
Category :
Languages : en
Pages : 0
Book Description
In every round of replication, the replisome encounters various forms of damage such as DNA breaks, protein-DNA crosslinks, and oxidized bases. Escherichia coli has evolved multiple pathways to repair the various types of DNA damage that accumulates in the cell. Recombinational repair is a non-mutagenic repair pathway that utilizes a neighboring undamaged duplex to restore lost genetic information. Our lab has recently implicated the E. coli Uup and RadD in the recombinational repair of a wide variety of DNA lesions. We show that the SF2 helicase RadD is essential when another helicase, RecG, is removed from the cell. This synthetically lethal phenotype allowed us to leverage existing knowledge of RecG to better understand the functions that become essential in its absence. Functions that are specifically carried out by RadD. This synthetically lethal phenotype is rapidly suppressed by mutations that affect replication restart (PriA) and homologous recombination (RecA). We also identify that a full gene deletion of uup is capable of suppressing the [Delta]rad[Delta]recG phenotype. By using a variety of biochemical and genetic approaches we show that Uup and RadD are involved in the processing of the intermediates generated by RecA-dependent and independent recombination in every replication cycle. When this activity is lost, these intermediates are targeted for alternative processing, by PriA and Uup. This alternative processing has deleterious consequences and results in cell death. Altogether, the results presented here shed further light on Uup and RadD and their roles in recombinational repair.
