Phylogenomic Analysis of Chloroplast Genome Evolution

Phylogenomic analysis of chloroplast genomes integrates high-throughput sequencing and comparative genomics to resolve evolutionary relationships among plants. Chloroplast genomes, typically 120–170 kb in size, exhibit a conserved quadripartite structure comprising large single-copy (LSC) and small single-copy (SSC) regions flanked by two inverted repeats (IRs). By sampling complete plastomes across diverse lineages, researchers can reconstruct phylogenies with enhanced resolution, infer divergence times and biogeographic histories, and detect patterns of gene loss, rearrangement and selection. Studies have revealed that variation in IR boundary placement and hotspot regions in coding and intergenic spacers provide robust markers for species delimitation, while integration of chloroplast and nuclear ribosomal data uncovers instances of hybridisation, incomplete lineage sorting and cytoplasmic introgression. Applications range from elucidating crop domestication pathways and reconstructing rapid radiations in complex clades to informing conservation strategies for endangered taxa and guiding marker-assisted breeding programmes. The global significance of this work lies in its ability to chart green plant diversity, clarify taxonomic ambiguities and underpin sustainable management of genetic resources.

Research from Nature Portfolio

Recent studies have produced complete chloroplast genome sequences alongside nuclear ribosomal units to refine family-level phylogenies and date key divergence events. In one investigation, ten species of the Araliaceae were analysed to reveal two major monophyletic lineages separated around 8–11 million years ago, with insights into conserved photosynthetic and ribosomal genes and lineage-specific nucleotide variation. In another study of 30 accessions across nine rice species, concurrent phylogenomic reconstruction using plastome and ribosomal data resolved inter-species relationships, clarified the impact of hybridisation on cytoplasmic lineages and pinpointed the geographic origins of cultivated rice, thereby advancing understanding of domestication and gene flow in the Oryza AA genome complex.

Phylogenomic Analysis of Chloroplast Genome Evolution publication trend

The graph below shows the total number of articles in phylogenomic analysis of chloroplast genome evolution across all publications each year (not limited to Nature Index journals).

Technical terms

Phylogenomics: The study of evolutionary relationships using genome-scale data.

Plastome: The complete chloroplast genome of a plant.

Quadripartite structure: Organisation of the plastome into two inverted repeats and two single-copy regions.

Inverted repeats (IRs): Identical sequences in opposite orientation that flank the single-copy regions.

Single-nucleotide polymorphism (SNP): A single base-pair variation in a genome, used as a genetic marker.

Molecular marker: A specific DNA sequence used to track inheritance or distinguish taxa.

References

1. Evolution of the Araliaceae family inferred from complete chloroplast genomes and 45S nrDNAs of 10 Panax-related species. Scientific Reports (2017).
2. Complete chloroplast and ribosomal sequences for 30 accessions elucidate evolution of Oryza AA genome species. Scientific Reports (2015).
3. Pan-chloroplast genomes for accession-specific marker development in Hibiscus syriacus. Scientific Data (2024).
4. Comparative Analysis of Six Complete Plastomes of Tripterospermum spp.. International Journal of Molecular Sciences (2024).
5. Comparative chloroplast genomics of 34 species in subtribe Swertiinae (Gentianaceae) with implications for its phylogeny. BMC Plant Biology (2023).