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Transcripts and sequence elements suggest differential promoter usage within the ycf3-psaAB gene cluster on mustard (Sinapis alba L.) chloroplast DNA.

H Summer·T Pfannschmidt·G Link
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Abstract

The mustard chloroplast DNA region spanning the ycf3 gene and part of the psaAB operon was investigated. The ycf3 gene reveals two class-II introns that are removed during processing to give a mature 0.7-kb transcript, but no RNA editing seems to be involved. RNase protection and RT-PCR experiments suggest cotranscription of ycf3 with the downstream psaA gene, possibly from a NEP promoter upstream of ycf3, whereas distinct ycf3 and psaA transcripts are each initiated from PEP promoters. This situation is reminiscent of that for the trnK-psbA gene region. The implications for light-regulated versus light-independent expression of photosystem core-protein genes are discussed.

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Amino Acid SequenceBase SequenceDNA, ChloroplastExonsGene Expression Regulation, PlantGenes, PlantIntronsLight-Harvesting Protein ComplexesMembrane ProteinsMolecular Sequence DataMustard PlantOperonPhotosynthetic Reaction Center Complex ProteinsPhotosystem I Protein ComplexPlant ProteinsPlants, MedicinalPromoter Regions, GeneticRNA SplicingRNA, ChloroplastRNA, MessengerSequence AlignmentTerminator Regions, GeneticTranscription, GeneticJournal ArticleResearch Support, Non-U.S. Gov't

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H Summer, T Pfannschmidt, G Link. 2000. Transcripts and sequence elements suggest differential promoter usage within the ycf3-psaAB gene cluster on mustard (Sinapis alba L.) chloroplast DNA.. https://doi.org/10.1007/s002940050007

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