Structural characteristics and phylogenetic analysis of the complete mitochondrial genome of Sanguisorba officinalis (Rosaceae)

Sanguisorba officinalis , a wild forage grass in the Rosaceae family that is widely distributed throughout China, is characterized by its tenderness, hairless foliage, and odorlessness. This species is highly appreciated as a food and traditional Chinese herbal medicine and for its ornamental value. However, research on the genomics of S. officinalis , particularly its mitochondrial genome, remains limited. In the present investigation, the mitochondrial genome of S. officinalis was sequenced and assembled, and a single master circular molecule 295,903 bp in length was identified. Thirty-three protein-coding, twenty-four transfer RNA, and three ribosomal RNA genes were among the sixty genes that were successfully annotated. Among these, atp8 exhibited high nucleotide polymorphism across six Rosaceae species. In the mitochondrial genome of S. officinalis , we detected 76 simple sequence repeats (SSRs), 50 dispersed repeats, and 15 tandem repeats. Notably, 460 RNA editing sites were detected among 32 distinct protein-coding genes (PCGs), all of which involved cytosine-to-uracil conversion, and 68 DNA fragments generated from chloroplasts were determined to have been transferred from the chloroplast genome to the mitochondrial genome. Finally, a phylogenetic tree was constructed using the mitochondrial genome data of 29 Rosaceae species and two outgroup species to validate the evolutionary relationships within Rosaceae. This study provides insights into the genetic background of S. officinalis , as well as useful findings for the exploration and practical application of Rosaceae germplasm resources.