Mechanism of initiation of yeast mitochondrial DNA replication: Role of RNA polymerase.

Yeast mitochondrial RNA polymerase was purified and resolved into 2 distinct fractions. Peak A was found to be nonspecific and exhibited characteristics of the core polymerase, whereas peak Β exhibited characteristics of the holoenzyme. In vitro replication assays were carried out, using the peak Β enzyme, the cloned ori sequences and other DNA templates. It was found that ori 2 was the most efficient template for RNA polymerase primed DNA synthesis, as compared to all the other templates studied.