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Updated: Jun 4, 2026

Discrimintion and Mapping of the Primary and Processed Transcripts in Maize Mitochondrion Using a Circular RT-PCR-based Strategy
Published on: July 29, 2019
The transcription machineries of plant mitochondria and chloroplasts: Composition, function, and regulation
Karsten Liere1, Andreas Weihe, Thomas Börner
1Institut für Biologie/Genetik, Humboldt-Universität zu Berlin, Chausseestrasse 117, Berlin, Germany.
Abstract:
Although genomes of mitochondria and plastids are very small compared to those of their bacterial ancestors, the transcription machineries of these organelles are of surprising complexity. With respect to the number of different RNA polymerases per organelle, the extremes are represented on one hand by chloroplasts of eudicots which use one bacterial-type RNA polymerase and two phage-type RNA polymerases to transcribe their genes, and on the other hand by Physcomitrella possessing three mitochondrial RNA polymerases of the phage type. Transcription of genes/operons is often driven by multiple promoters in both organelles. This review describes the principle components of the transcription machineries (RNA polymerases, transcription factors, promoters) and the division of labor between the different RNA polymerases. While regulation of transcription in mitochondria seems to be only of limited importance, the plastid genes of higher plants respond to exogenous and endogenous cues rather individually by altering their transcriptional activities.
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