Assembly and comparative analysis of the complete mitochondrial genome of Vaccinium carlesii Dunn.

ABSTRACT

Vaccinium L. is an important fruit tree with nutritional, medicinal, and ornamental values. However, the mitochondrial (mt) genome of Vaccinium L. remains largely unexplored. Vaccinium carlesii Dunn is an endemic wild resource in China, which is crucial for blueberry breeding. The V. carlesii mt genomes were sequenced using Illumina and Nanopore, which total length was 636,904 bp with 37 protein coding genes, 20 tRNA genes, and three rRNA genes. We found four pairs of long repeat fragments homologous recombination mediated the generation of substructures in the V. carlesii mt genome. We predicted 383 RNA editing sites, all converting cytosine (C) to uracil (U). According to the phylogenetic analysis, V. carlesii and V. macrocarpon of the Ericaceae exhibited the closest genetic relationship. This study provides a theoretical basis for understanding the evolution of higher plants, species classification and identification, and will also be useful for further utilization of Vaccinium germplasm resources.