Identification of multiple rate-limiting steps during the human mitochondrial transcription cycle in vitro.

ABSTRACT: We have reconstituted human mitochondrial transcription in vitro on DNA oligonucleotide templates representing the light strand and heavy strand-1 promoters using protein components (RNA polymerase and transcription factors A and B2) isolated from Escherichia coli. We show that 1 eq of each transcription factor and polymerase relative to the promoter is required to assemble a functional initiation complex. The light strand promoter is at least 2-fold more efficient than the heavy strand-1 promoter, but this difference cannot be explained solely by the differences in the interaction of the transcription machinery with the different promoters. In both cases, the rate-limiting step for production of the first phosphodiester bond is open complex formation. Open complex formation requires both

SUBMITTER: Lodeiro MF 

PROVIDER: S-EPMC2871506 | biostudies-literature | 2010 May

REPOSITORIES: biostudies-literature