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PubMed · 11258484

One RNA polymerase serving two genomes.

B Hedtke·T Börner·A Weihe
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Abstract

The land plant Arabidopsis thaliana contains three closely related nuclear genes encoding phage-type RNA polymerases (RpoT;1, RpoT;2 and RpoT;3). The gene products of RpoT;1 and RpoT;3 have previously been shown to be imported into mitochondria and chloroplasts, respectively. Here we show that the transit peptide of RpoT;2 possesses dual targeting properties. Transient expression assays in tobacco protoplasts as well as stable transformation of Arabidopsis plants demonstrate efficient targeting of fusion peptides consisting of the N-terminus of RpoT;2 joined to green fluorescent protein to both organelles. Thus, RpoT;2 might be the first RNA polymerase shown to transcribe genes in two different genomes. RNA polymerase activity of recombinant RpoT;2 is uneffected by the inhibitor tagetin, qualifying the gene product of RpoT;2 as a phage-type polymerase.

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Amino Acid SequenceArabidopsisCloning, MolecularDNA, ComplementaryDNA-Directed RNA PolymerasesEscherichia coliFluorescein-5-isothiocyanateGenomeGreen Fluorescent ProteinsLuminescent ProteinsMicroscopy, FluorescenceMitochondriaModels, GeneticMolecular Sequence DataPeptidesPlants, ToxicPlastidsRecombinant Fusion ProteinsSequence Homology, Amino AcidNicotianaTranscription, GeneticJournal ArticleResearch Support, Non-U.S. Gov't

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B Hedtke, T Börner, A Weihe. 2000. One RNA polymerase serving two genomes.. https://doi.org/10.1093/embo-reports%2Fkvd086

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