CNR ExploRA

Articolo in rivista, 2019, ENG, 10.3390/ijms20194788

Complete Sequence, Multichromosomal Architecture and Transcriptome Analysis of the Solanum tuberosum Mitochondrial Genome

Jean-Stéphane Varré 1,, Nunzio D'Agostino 2 , Pascal Touzet 3 , Sophie Gallina 3, Rachele Tamburino 4 , Concita Cantarella 2, Elodie Ubrig 5, Teodoro Cardi 2, Laurence Drouard 5, José Manuel Gualberto 5,* and Nunzia Scotti 4,*

1, Univ. Lille, CNRS, Centrale Lille, UMR 9189--CRIStAL--Centre de Recherche en Informatique Signal et Automatique de Lille, F-59000 Lille, France 2, CREA Research Centre for Vegetable and Ornamental Crops, 84098 Pontecagnano Faiano, SA, Italy 3, Univ. Lille, CNRS, UMR 8198--Evo-Eco-Paleo, F-59000 Lille, France 4, CNR-IBBR, National Research Council of Italy, Institute of Biosciences and BioResources, 80055 Portici, NA, Italy 5, Institut de Biologie Moléculaire des Plantes-CNRS, Université de Strasbourg, 67084 Strasbourg, France

Mitochondrial genomes (mitogenomes) in higher plants can induce cytoplasmic male sterility and be somehow involved in nuclear-cytoplasmic interactions affecting plant growth and agronomic performance. They are larger and more complex than in other eukaryotes, due to their recombinogenic nature. For most plants, the mitochondrial DNA (mtDNA) can be represented as a single circular chromosome, the so-called master molecule, which includes repeated sequences that recombine frequently, generating sub-genomic molecules in various proportions. Based on the relevance of the potato crop worldwide, herewith we report the complete mtDNA sequence of two S. tuberosum cultivars, namely Cicero and Désirée, and a comprehensive study of its expression, based on high-coverage RNA sequencing data. We found that the potato mitogenome has a multi-partite architecture, divided in at least three independent molecules that according to our data should behave as autonomous chromosomes. Inter-cultivar variability was null, while comparative analyses with other species of the Solanaceae family allowed the investigation of the evolutionary history of their mitogenomes. The RNA-seq data revealed peculiarities in transcriptional and post-transcriptional processing of mRNAs. These included co-transcription of genes with open reading frames that are probably expressed, methylation of an rRNA at a position that should impact translation efficiency and extensive RNA editing, with a high proportion of partial editing implying frequent mis-targeting by the editing machinery.

International journal of molecular sciences (Online) 20 , pp. 4788–?