Analyses of the Complete Mitochondrial Genome of Paraconiothyrium sp. and Gene Rearrangement Diversity in the Pleosporales

Abstract

The Pleosporales is the most predominant order in the Dothideomycetes class, which contains over 4700 species that function in a variety of ways. The material used in this research was previously isolated from the Chinese white wax scale insect, and it was determined to be a Paraconiothyrium genus species that belonged to the Pleosporales order. For further molecular analysis, we assembled the complete mitochondrial genome of Paraconiothyrium sp. based on short reads of BGISEQ sequencing and subreads from Pacbio sequencing. The results showed that it was 42,734 bp in length and contained 8 open reading frames, 12 protein-coding genes and 31 non-coding genes. Phylogenetic analysis showed it was affiliated to the Pleosporales order and formed a sister relationship with Pithomyces chartarum. Compared to the seven other species in the Pleosporales order, Paraconiothyrium sp. has generally conserved gene content and structure, while the homologous blocks and gene order were shown to be significantly rearranged, in accordance with the species diversity in the Pleosporales order. In this study, we presented the first mitochondrial genome of Paraconiothyrium fungi to be reported, and we also showed gene order diversity in the Pleosporales order. These findings will lay the foundation for further species studies regarding molecular diversity and our understanding of species characteristics in the Paraconiothyrium genus.