# The First Complete Mitochondrial Genome of Corydalis impatiens (Papaveraceae) and Its Phylogenetic Implications

## TL;DR

This study reports the first complete mitochondrial genome of the Tibetan medicinal plant Corydalis impatiens and explores its evolutionary adaptations to high-altitude environments.

## Contribution

The first complete mitochondrial genome of an alpine Corydalis species, providing insights into high-altitude adaptation and phylogenetic relationships.

## Key findings

- The mitochondrial genome is 688,959 bp with 74 genes and distinct GC content patterns across gene types.
- 719 RNA editing sites were identified, particularly in NADH dehydrogenase genes, indicating adaptation to hypoxia.
- The genome contains 50 repeats and 67 SSRs, offering markers for authenticating the medicinal plant 'Pa Xia Ga'.

## Abstract

Corydalis impatiens (Papaveraceae) is a traditional Tibetan medicinal plant (“Pa Xia Ga”) whose mitochondrial genome evolution remains unexplored, particularly in the context of high-altitude adaptation. This study presents the first complete mitochondrial genome sequence of an alpine Corydalis species to establish a comparative framework with the lowland congener C. pauciovulata for investigating environment-associated mitochondrial evolution. Using Illumina sequencing and reference-guided assembly, we characterized a 688,959 bp circular genome containing 74 genes, with GC content variations reflecting functional compartmentalization—elevated in structural RNA genes (tRNAs: 51.24%; rRNAs: 52.79%) versus protein-coding genes (44.19%). We identified 719 RNA editing sites concentrated in NADH dehydrogenase genes, suggesting post-transcriptional optimization of respiratory complex I under hypoxic conditions. The genome harbors 50 dispersed repeats (7.50%) and 67 SSRs with A-rich predominance, providing species-specific markers for authenticating “Pa Xia Ga” in Tibetan medicine quality control. Phylogenomic analysis confirms close affinity with C. pauciovulata while resolving intrageneral relationships within Ranunculales. These findings establish a dual-reference system for distinguishing conserved genus-level features from altitude-associated adaptations, enabling future comparative mitogenomics across the 465-species genus and supporting DNA-based medicinal plant identification.