Cloned (Comment) | Organism |
---|---|
recombinant expression of POL3 containing a cleavable N-terminal GST-tag, and of POL31 and POL32 from the galactose-inducible GAL1-10 promoter in protease-deficient strain BJ2168, expression of c-Myc-tagged catalytic subunits Pol1, Pol2, and Pol3 in Escherichia coli strain BL21. Expression of the C-terminal domain of Pol3 (amino acids 982-1097) with a N-terminal HA epitope tag or C-terminally Strep-tagged CTD domains of Pol1, Pol2, Pol3 in Escherichia coli strain HMS174 (DE3) pLysS | Saccharomyces cerevisiae |
Localization | Comment | Organism | GeneOntology No. | Textmining |
---|---|---|---|---|
mitochondrion | - |
Saccharomyces cerevisiae | 5739 | - |
Metals/Ions | Comment | Organism | Structure |
---|---|---|---|
Fe2+ | required, in [4Fe-4S] clusters, that are bound to the CysB motif in all yeast B family DNA polymerases, assembly of the essential Fe-S cluster is strictly dependent on the function of mitochondrial Nfs1 and cytosolic Nbp35. The C-terminal domain of the catalytic subunit binds the Fe-S cluster in the CysB motif requiring all Cys residues of motif Cysb | Saccharomyces cerevisiae | |
Zn2+ | required, Zn2+ is bound to the CysA motif in yeast B family DNA polymerases | Saccharomyces cerevisiae |
Organism | UniProt | Comment | Textmining |
---|---|---|---|
Saccharomyces cerevisiae | - |
- |
- |
Saccharomyces cerevisiae W303-1A | - |
- |
- |
Purification (Comment) | Organism |
---|---|
GST-tagged POL3, POL31, and POL32 by glutathione affinity chromatography | Saccharomyces cerevisiae |
Subunits | Comment | Organism |
---|---|---|
More | the catalytic subunits Pol1, Pol2 and Pol3 are phylogenetically related, and belong to the class B DNA polymerases | Saccharomyces cerevisiae |
tetramer | isozymes pol alpha and epsilon contain subunits Pol1, Pol12, Pri1, and Pri2, Pol2, Dpb2, Dpb3 and Dpb4, respectively | Saccharomyces cerevisiae |
trimer | isozyme pol delta contains subunits Pol3, Pol31 and Pol32 | Saccharomyces cerevisiae |
Synonyms | Comment | Organism |
---|---|---|
pol alpha | - |
Saccharomyces cerevisiae |
pol delta | - |
Saccharomyces cerevisiae |
POl epsilon | - |
Saccharomyces cerevisiae |
General Information | Comment | Organism |
---|---|---|
evolution | the catalytic subunits Pol1, Pol2 and Pol3 or isozymes pol alpha, pol epsilon, and pol delta are phylogenetically related, and belong to the class B DNA polymerases. The B subunits are all essential and share a phosphodiesterase-like and oligosaccharide binding domain. Eukaryotes contain a fourth class B DNA polymerase, Pol zeta, which is the major enzyme responsible for mutagenesis in response to DNA damage | Saccharomyces cerevisiae |
malfunction | weakened Fe-S cluster binding efficiency of CysA mutant proteins, caused by a lack of polymerase complex stabilization by Pol31, even though this subunit interacts primarily with the CysB region, overexpression of Pol31 results in a 4 to 8fold higher 55Fe binding to both wild-type and CysA mutant Pol3-CTDs. Depletion of the cysteine desulfurase Nfs1 by growth on glucose of the galactose-regulatable strain Gal-NFS1 almost completely abolishes Fe binding to the polymerases, and depletion of the CIA machinery components Nbp35 and Nar1 in regulatable yeast strains abrogates Fe-S cluster formation on the polymerases | Saccharomyces cerevisiae |
additional information | physiological importance of the two different metal cofactors, the [4Fe-4S] cluster in CysB and Zn2+ in CysA, in the stabilization of DNA polymerase interactions with different accessory proteins essential for processive DNA synthesis at the replication fork. CysA is an important determinant for proliferating cell nuclear antigen binding | Saccharomyces cerevisiae |