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.

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.

Figures