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bioRxiv · 10.1101/2020.10.22.346726

Insights into the mitochondrial transcriptome landscapes of two Brassicales plant species, Arabidopsis thaliana (var. Col-0) and Brassica oleracea (var. botrytis)

Abstract

Mitochondria play key roles in cellular energy metabolism within eukaryotic cells. As relics of endosymbiotic bacteria, most (but not all) mitochondria contain their own genome (mitogenome, mtDNA), as well as intrinsic biosynthetic machinery for making organelle RNAs and proteins. The expression of the mtDNA requires regulated metabolism of its transcriptome by nuclear-encoded factors. Post-transcriptional mtRNA modifications play a central role in the expression of the plant mitogenomes, and hence in organellar biogenesis and plant physiology. Despite extensive investigations, a full map of angiosperm mitochondrial transcriptomes, a prerequisite for the elucidation of the basic RNA biology of mitochondria, has not been reported yet. Using RNA-seq data, RT-PCR and bioinformatics, we sought to explore the gene expression profiles of land plant mitochondria. Here, we present the mitochondrial transcriptomic maps of two key Brassicaceae species, Arabidopsis thaliana (var Col-0) and cauliflower (Brassica oleracea var. botrytis). The revised transcriptome landscapes of Arabidopsis and cauliflower mitogenomes provide with more detail into mtRNA biology and processing in angiosperm mitochondria, and we expect that they would serve as a valuable resource for the plant organellar community. Accession numbersSequences are available at the Sequence Read Archive (accession no. PRJNA472433), for both Arabidopsis thaliana var. Col-0 mtRNA (SRA no. SRX4110179) and Brassica oleracea var. botrytis mtRNA (SRA no. SRX4110177).

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Best, C., Sultan, L. D., Murik, O., Ostersetzer, O.. 2020-10-22. Insights into the mitochondrial transcriptome landscapes of two Brassicales plant species, Arabidopsis thaliana (var. Col-0) and Brassica oleracea (var. botrytis). https://doi.org/10.1101/2020.10.22.346726

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