Assembly of the Complete Mitochondrial Genome of Chinese Plum (<i>Prunus salicina</i>): Characterization of Genome Recombination and RNA Editing Sites

Despite the significant progress that has been made in the genome sequencing of <i>Prunus</i>, this area of research has been lacking a systematic description of the mitochondrial genome of this genus for a long time. In this study, we assembled the mitochondrial genome of the Chinese pl...

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Bibliographic Details
Main Authors: Bo Fang, Jingling Li, Qian Zhao, Yuping Liang, Jie Yu
Format: Article
Language:English
Published: MDPI AG 2021-12-01
Series:Genes
Subjects:
Online Access:https://www.mdpi.com/2073-4425/12/12/1970
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Summary:Despite the significant progress that has been made in the genome sequencing of <i>Prunus</i>, this area of research has been lacking a systematic description of the mitochondrial genome of this genus for a long time. In this study, we assembled the mitochondrial genome of the Chinese plum (<i>Prunus salicina</i>) using Illumina and Oxford Nanopore sequencing data. The mitochondrial genome size of <i>P. salicina</i> was found to be 508,035 base pair (bp), which is the largest reported in the Rosaceae family to date, and <i>P. salicina</i> was shown to be 63,453 bp longer than sweet cherry (<i>P. avium</i>). The <i>P. salicina</i> mitochondrial genome contained 37 protein-coding genes (PCGs), 3 ribosomal RNA (rRNA) genes, and 16 transfer RNA (tRNA) genes. Two plastid-derived tRNA were identified. We also found two short repeats that captured the <i>nad</i>3 and <i>nad</i>6 genes and resulted in two copies. In addition, nine pairs of repeat sequences were identified as being involved in the mediation of genome recombination. This is crucial for the formation of subgenomic configurations. To characterize RNA editing sites, transcriptome data were used, and we identified 480 RNA editing sites in protein-coding sequences. Among them, the initiation codon of the <i>nad</i>1 gene confirmed that an RNA editing event occurred, and the genomic encoded ACG was edited as AUG in the transcript. Combined with previous reports on the chloroplast genome, our data complemented our understanding of the last part of the organelle genome of plum, which will facilitate our understanding of the evolution of organelle genomes.
ISSN:2073-4425