Transcription from the second heavy-strand promoter of human mtDNA is repressed by transcription factor A in vitro.

ABSTRACT: Cell-based studies support the existence of two promoters on the heavy strand of mtDNA: heavy-strand promoter 1 (HSP1) and HSP2. However, transcription from HSP2 has been reported only once in a cell-free system, and never when recombinant proteins have been used. Here, we document transcription from HSP2 using an in vitro system of defined composition. An oligonucleotide template representing positions 596-685 of mtDNA was sufficient to observe transcription by the human mtRNA polymerase (POLRMT) that was absolutely dependent on mitochondrial transcription factor B2 (TFB2M). POLRMT/TFB2M-dependent transcription was inhibited by concentrations of mitochondrial transcription factor A (TFAM) stoichiometric with the transcription template, a condition that activates transcription from the lig

SUBMITTER: Lodeiro MF 

PROVIDER: S-EPMC3340051 | biostudies-literature | 2012 Apr

REPOSITORIES: biostudies-literature