A trypanosome mitochondrial RNA polymerase is required for transcription and replication

Jayleen Grams, James C. Morris, Mark E. Drew, Zefeng Wang, Paul T. Englund, Stephen L. Hajduk

Research output: Contribution to journalArticle


Understanding mitochondrial transcription is a requisite first step toward understanding the regulation of mitochondrial gene expression in kinetoplastids. Here we report the identification and functional characterization of a mitochondrial RNA polymerase (mtRNAP) from Trypanosoma brucei, the first trans-acting factor involved in kinetoplast mitochondrial transcription to be identified. Using sequences conserved among the catalytic domains of the single-subunit mtRNAPs, we were able to obtain a full-length sequence for a candidate mtRNAP from T. brucei. Sequence comparison indicates that it shares homology in its catalytic domain with other single-subunit mtRNAPs, including functionally conserved residues that are identical in all single-subunit RNAPs. We used RNA interference to functionally knock out the gene product to determine whether the candidate gene represents an mtRNAP. As predicted for a mitochondrial specific RNA polymerase, reduction of the gene product resulted in a specific decrease of mitochondrial versus nuclear transcripts. Additionally, similar to the mtRNAP of other organisms, the mtRNAP characterized here is involved in replication of the mitochondrial genome. Thus, based on sequence comparison and functional studies, we have cloned an mtRNAP from trypanosomes.

Original languageEnglish (US)
Pages (from-to)16952-16959
Number of pages8
JournalJournal of Biological Chemistry
Issue number19
Publication statusPublished - May 10 2002
Externally publishedYes


ASJC Scopus subject areas

  • Biochemistry

Cite this

Grams, J., Morris, J. C., Drew, M. E., Wang, Z., Englund, P. T., & Hajduk, S. L. (2002). A trypanosome mitochondrial RNA polymerase is required for transcription and replication. Journal of Biological Chemistry, 277(19), 16952-16959. https://doi.org/10.1074/jbc.M200662200