Great Burnet Mitochondrial Genome Assembled to Reveal Rosaceae Evolution

Researchers have sequenced and assembled the complete mitochondrial genome of Sanguisorba officinalis, a widely distributed member of the rose family valued in China as forage, food, traditional herbal medicine and an ornamental plant. The work, published open access in BMC Genomics, identifies a single master circular molecule of 295,903 base pairs and provides a detailed mitochondrial genome characterization for this species, whose genomic resources had previously remained limited.

The assembled genome yielded sixty successfully annotated genes. Of these, thirty-three are protein-coding genes, twenty-four encode transfer RNAs and three encode ribosomal RNAs. This gene complement establishes a reference baseline for the organellar genetics of S. officinalis, a species described by the authors as a wild forage grass in the Rosaceae family with tender, hairless and odorless foliage.

Comparative analysis across six Rosaceae species highlighted atp8, a protein-coding gene, as showing high nucleotide polymorphism within the family. This variation marks atp8 as a notably divergent mitochondrial locus among the sampled relatives.

Repeat structure emerged as a prominent feature of the genome. The team detected 76 simple sequence repeats, 50 dispersed repeats and 15 tandem repeats, and their cataloguing provides a structural map for subsequent work on this genome.

RNA editing proved extensive. The researchers identified 460 RNA editing sites in the mitochondrial genome, and every detected event involved a cytosine-to-uracil conversion. This documents the scale of post-transcriptional modification associated with the genome’s protein-coding content.

The assembly also captured evidence of organelle-to-organelle DNA transfer. In total, 68 DNA fragments originating from the chloroplast genome were determined to have been transferred into the mitochondrial genome of S. officinalis. This chloroplast-derived DNA documents the flow of genetic material between the two organelles and adds to the structural characterization of the mitochondrial molecule.

To place the species in an evolutionary context, the authors constructed a phylogenetic tree from mitochondrial genome data covering 29 Rosaceae species together with two outgroup species. The analysis was used to validate evolutionary relationships within Rosaceae, adding mitochondrial evidence to the family’s known phylogenetic framework.

The study’s authors frame the results as insights into the genetic background of S. officinalis and as findings useful for the exploration and practical application of Rosaceae germplasm resources. A complete reference sequence of this kind supplies a foundation for future genetic investigations in the family.

As with any single-species genome report, the findings describe one assembled mitochondrial molecule and comparative patterns within the sampled Rosaceae set rather than broader functional or agronomic outcomes. The value of the work lies in the annotated reference itself: a defined gene inventory, a quantified repeat landscape, a complete tally of RNA editing sites and a documented record of chloroplast-derived insertions, all now available for further study of S. officinalis and its relatives.

Subject of Research: Complete mitochondrial genome assembly and phylogenetic analysis of Sanguisorba officinalis (Rosaceae)

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

Article References: Wu, D., Tian, C., Yang, Y., Liu, L., Gong, W., Feng, Y., Li, Y., Li, Z., & Wu, Z. (2026). Structural characteristics and phylogenetic analysis of the complete mitochondrial genome of Sanguisorba officinalis (Rosaceae). BMC Genomics. https://doi.org/10.1186/s12864-026-13493-1

Image Credits: AI Generated

DOI: 10.1186/s12864-026-13493-1

Keywords: Sanguisorba officinalis, mitochondrial genome, Rosaceae, genomics, RNA editing, chloroplast DNA transfer, phylogenetics, simple sequence repeats, atp8, BMC Genomics, Structural, characteristics