The first complete mitochondrial genome of Curcuma amarissima (Zingiberaceae): insights into multi-branch structure, codon usage, and phylogenetic evolution.

Summary

Using both Nanopore and Illumina sequencing, the authors generated the first complete mitochondrial genome in Zingiberaceae, revealing a 6.5 Mb, 39-segment multi-branched architecture with weak codon usage bias and abundant repeats. The resource enables phylogenetic analyses and supports breeding, conservation, and molecular studies of Curcuma—relevant to botanical ingredients used in cosmetics.

Key Findings

• First complete mitochondrial genome in Zingiberaceae using combined Illumina and Nanopore sequencing
• Large, multi-branched mitogenome (6,505,655 bp; 39 segments) with 43 PCGs, 63 tRNAs, 4 rRNAs, GC 44.04%
• Weak codon usage bias and neutrality plot suggesting natural selection influences codon usage
• High repeat content potentially contributing to mitochondrial structural stability
• Phylogenetic analyses based on the mitogenome provide a framework for Zingiberaceae evolution

Clinical Implications

No direct clinical practice change; however, improved genomic resources can enhance traceability, quality control, and breeding of Curcuma-derived cosmetic ingredients.

Limitations

• Single-species mitogenome; generalizability across Curcuma not established
• No functional validation linking structure to mitochondrial function or phenotype

Future Directions

Expand mitogenome sequencing across Curcuma/Zingiberaceae, integrate nuclear/chloroplast genomes, and functionally probe the roles of repeats and multi-branch architecture.