The global obesity epidemic affects billions of people (1), and, in its wake, a worldwide epidemic of type 2 diabetes has followed (2,3). Obesity is not only associated with diabetes, of course, but also with the other partners in the X-gang: hypertension, hyperlipidemia, and cardiovascular disease (4). As exemplified in an original article in this issue of Diabetes (5), the link between diabet...

As first observed by Wittenberg (Kesti, T., Flick, K., Keranen, S., Syvaoja, J. E., and Wittenburg, C. (1999) Mol. Cell 3, 679–685), we find that deletion mutants lacking the entire N-terminal DNA polymerase domain of yeast pol e are viable. However, we now show that point mutations in DNA polymerase catalytic residues of pol e are lethal. Taken together, the phenotypes of the deletion and the ...

Escherichia coli DNA polymerase IV (Pol IV, also known as DinB) is a Y-family DNA polymerase capable of catalyzing translesion DNA synthesis (TLS) on certain DNA lesions, and accumulating data suggest that Pol IV may play an important role in copying various kinds of spontaneous DNA damage including N(2)-dG adducts and alkylated bases. Pol IV has a unique ability to coexist with Pol III on the ...

The ability of a series of haloalkanes, haloethanols and haloacetaldehydes to induce mutations in Salmonella typhrimurium and preferentially to inhibit the growth of DNA polymerase-deficient E. coli (pol A(+)/pol A(-)) was investigated. For the haloalkanes investigated, the order of reactivities towards the E. coli pol A(+)/pol A(-), was: 1,1,2,2-tetrabromoethane > 1,1-dibromoethane > 1,1,2,2-t...

Multisubunit RNA polymerases IV and V (Pol IV and Pol V) evolved as specialized forms of Pol II that mediate RNA-directed DNA methylation (RdDM) and transcriptional silencing of transposons, viruses, and endogenous repeats in plants. Among the subunits common to Arabidopsis thaliana Pols II, IV, and V are 93% identical alternative ninth subunits, NRP(B/D/E)9a and NRP(B/D/E)9b. The 9a and 9b sub...

Escherichia coli DNA polymerase IV (Pol IV) is involved in bypass replication of damaged bases in DNA. Reactive oxygen species (ROS) are generated continuously during normal metabolism and as a result of exogenous stress such as ionizing radiation. ROS induce various kinds of base damage in DNA. It is important to examine whether Pol IV is able to bypass oxidatively damaged bases. In this study...

This report demonstrates that the beta sliding clamp of E. coli binds two different DNA polymerases at the same time. One is the high-fidelity Pol III chromosomal replicase and the other is Pol IV, a low-fidelity lesion bypass Y family polymerase. Further, polymerase switching on the primed template junction is regulated in a fashion that limits the action of the low-fidelity Pol IV. Under cond...

The fidelity of Schizosaccharomyces pombe DNA polymerase delta was measured in the presence or absence of its processivity subunits, proliferating cell nuclear antigen (PCNA) sliding clamp and replication factor C (RFC) clamp-loading complex, using a synthetic 30-mer primer/100-mer template. Synthesis by pol delta alone was distributive. Processive synthesis occurred in the presence of PCNA, RF...