Abstract
In plants and algae, the replication enzyme of organellar genomes has not been identified. The mitochondrial replication enzyme in animals, DNA polymerase gamma, is not encoded by the completely sequenced genomes of Arabidopsis thaliana and Cyanidioschyzon merolae. Genes encoding two DNA polymerases having homology to Escherichia coli DNA polymerase I in the nuclear genome of C. merolae were found (termed PolA and PolB). We examined intracellular localization of PolA and PolB by use of fused protein with GFP and immunoblotting analysis using isolated plastids from C. merolae. These results suggested that PolA and PolB are both localized to plastids and mitochondria. We measured enzymatic activity of PolA, PolB and plastid nucleoids of C. merolae and compared these characteristics. We are now analyzing the expression of these polymerases in synchronized culture.
