A transcription factor required for promoter recognition by human mitochondrial RNA polymerase. Accurate initiation at the heavy- and light-strand promoters dissected and reconstituted in vitro.

janelia7_blocks-janelia7_biblio_header | block

The Journal of Biological Chemistry. 1985 Sep 15;260:11330-8. doi: 10.1101/gad.1352105

Fisher RP, Clayton DA

Note: Research in this publication was not performed at Janelia.

janelia7_blocks-janelia7_biblio_abstract | block

Abstract

Faithful transcription of human mitochondrial DNA has been reproduced in vitro, using a fraction of mitochondrial proteins capable of accurate initiation at both the heavy- and light-strand promoters. Here we report the initial dissection of this system into two nonfunctional components which, upon mixing, reconstitute promoter-specific transcriptional capacity in vitro. One of these components copurifies with the major nonspecific RNA polymerase activity, suggesting its identity. The other component lacks significant polymerase activity, but contains a protein or proteins required for accurate initiation at the two individual promoters by isolated mitochondrial RNA polymerase. This factor facilitates specific transcription, but has little or no effect on nonspecific transcription of a synthetic copolymer (poly(dA-dT)), indicating a positive role in proper promoter recognition. The transcription factor markedly stimulates light-strand transcription, but only moderately enhances transcription initiation at the heavy-strand promoter, suggesting different or additional factor requirements for heavy-strand transcription. These requirements may reflect the functional differences between heavy- and light-strand transcription in vivo and, in particular, the role of the light-strand promoter in priming of heavy-strand DNA replication.

node:body | entity_field

Main Menu (Mobile)- Block

Main Menu - Block

A transcription factor required for promoter recognition by human mitochondrial RNA polymerase. Accurate initiation at the heavy- and light-strand promoters dissected and reconstituted in vitro.

Note: Research in this publication was not performed at Janelia.

Abstract