DNA polymerase I acts in translesion synthesis mediated by the Y-polymerases in Bacillus subtilis.


Translesion synthesis (TLS) across damaged DNA bases is most often ...
Translesion synthesis (TLS) across damaged DNA bases is most often carried out by the ubiquitous error-prone DNA polymerases of the Y-family. Bacillus subtilis encodes two Y-polymerases, Pol Y1 and Pol Y2, that mediate TLS resulting in spontaneous and ultraviolet light (UV)-induced mutagenesis respectively. Here we show that TLS is a bipartite dual polymerase process in B. subtilis, involving not only the Y-polymerases but also the A-family polymerase, DNA polymerase I (Pol I). Both the spontaneous and the UV-induced mutagenesis are abolished in Pol I mutants affected solely in the polymerase catalytic site. Physical interactions between Pol I and either of the Pol Y polymerases, as well as formation of a ternary complex between Pol Y1, Pol I and the beta-clamp, were detected by yeast two- and three-hybrid assays, supporting the model of a functional coupling between the A- and Y-family polymerases in TLS. We suggest that the Pol Y carries the synthesis across the lesion, and Pol I takes over to extend the synthesis until the functional replisome resumes replication. This key role of Pol I in TLS uncovers a new function of the A-family DNA polymerases.




new topics/pols set partial results complete validated


No results available for this paper.

Entry validated by:

Using Polbase tables:


Tables may be sorted by clicking on any of the column titles. A second click reverses the sort order. <Ctrl> + click on the column titles to sort by more than one column (e.g. family then name).


It is also possible to filter the table by typing into the search box above the table. This will instantly hide lines from the table that do not contain your search text.