Characterization of an RNA Polymerase Activity from HeLa Cell Mitochondria, Which Initiates Transcription at the Heavy Strand rRNA Promoter and the Light Strand Promoter in Human Mitochondrial DNA
- Creators
- Shuey, David J.
- Attardi, Giuseppe
Abstract
An RNA polymerase activity capable of initiating transcription at both the heavy strand rRNA promoter and the light strand promoter of human mitochondrial DNA has been partially purified from HeLa cell mitochondria and characterized in its requirements and products. The ratio of the two transcription initiating activities varied considerably from preparation to preparation. The human mtRNA polymerase partially purified by DEAE-cellulose and heparin-agarose chromatography exhibits a great sensitivity to ionic strength and to Mn^(2+), characteristics which clearly differentiate this enzyme from bacterial and eukaryotic nuclear RNA polymerases, and in contrast resemble the behavior of the yeast mtRNA polymerase. The human mtRNA polymerase exhibits a requirement for ATP which is 15- to 20-fold higher than that for the other NTPs, a low optimum template DNA concentration, and a marked susceptibility to inhibition by non-mitochondrial DNA.
Additional Information
© 1985 by The American Society of Biological Chemists. Received for publication, June 11, 1984. These investigations were supported by National Institutes of Health Grants GM-11726 and T32 GM076165. The costs of publication of this article were defrayed in part by the payment of page charges. This article must therefore be hereby marked· "advertisement" in accordance with 18 U.S.C. Section 1734 solely to indicate this fact. We are greatly indebted to Michael King and George Gaines for supplying us with pUC-9 and M13 clones of human mtDNA, to B. Greenberg for the plasmid pBHK2, and to J. Campbell for a gift of mouse topoisomerase I. We also thank Carl Parker, George Gaines, and Anne Chomyn for their critical reading of the manuscript. The technical assistance of Arger Drew is gratefully acknowledged.Additional details
- Eprint ID
- 32194
- Resolver ID
- CaltechAUTHORS:20120629-103338460
- GM-11726
- NIH
- T32 GM076165
- NIH
- Created
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2012-07-02Created from EPrint's datestamp field
- Updated
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2019-10-03Created from EPrint's last_modified field