20663713
not annotated - annotated - LINNAEUS only
Conservation of POPs, the plant organellar DNA polymerases, in eukaryotes.
POPs, plant organellar DNA polymerases, have been isolated from various photosynthetic eukaryotes. Previously, we purified the native POP of Cyanidioschyzon merolae (CmPOP) from whole cellular extracts and showed that CmPOP has DNA polymerase activity with a high processivity and a 3'-5' exonuclease activity, and its expression is related to cell proliferation. In rice, the recombinant protein of POP has activities found in CmPOP, and high fidelity of POP has also been demonstrated. These facts suggest that POPs are involved in the replication of organellar genomes. POPs are also conserved in most non-opisthokont eukaryotes, which lack DNA polymerase gamma (Polgamma), a mitochondrial replication enzyme in opisthokonts (fungi and animals). The ciliate Tetrahymena thermophila contains a single gene for a putative POP (TetPOP). Immunoblot analysis demonstrated that TetPOP is localized in mitochondria, and TetPOP has been purified from mitochondria through a column chromatography series. Sensitivity to phosphonoacetate and dideoxyTTP was examined in POPs (TetPOP and CmPOP) or POP-containing organelles (chloroplasts of Arabidopsis) and other polymerases (DNA polymerase I and mitochondria of rat liver, which contain Polgamma), and the results suggest that high sensitivity to phosphonoacetate is unique to POPs in Family-A DNA polymerases. Finally, we propose a model for the succession of organellar DNA polymerases.
Ann file
T1 Species 217 240 Cyanidioschyzon merolae
N1 Reference T1 Taxonomy:45157
T2 Species 443 447 rice
N2 Reference T2 Taxonomy:4530
T3 Species 837 860 Tetrahymena thermophila
N3 Reference T3 Taxonomy:5911
T4 Out-of-scope 1208 1219 Arabidopsis
T5 Species 1281 1284 rat
N5 Reference T5 Taxonomy:10116
N4 Reference T4 Taxonomy:3701 Arabidopsis