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Updated: Feb 28, 2026
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Robust DNA Isolation and High-throughput Sequencing Library Construction for Herbarium Specimens
Published on: March 8, 2018
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Chloroplast Genome Evolution in Pleurothallidinae (Orchidaceae): Lineage-Specific Selection, Codon Usage Patterns,
Yuxue Liu1, Qiang Zhang1, Zhenhua Wu1
1College of Biological Engineering, Qingdao University of Science and Technology, Qingdao 266042, China.
Genes
|February 27, 2026
Summary
Comparative plastome analysis of Pleurothallidinae orchids reveals lineage-specific selection and identifies new molecular markers. This study enhances our understanding of orchid genome evolution and aids future taxonomic research.
Area of Science:
- Orchidaceae genomics
- Plant evolutionary biology
- Molecular systematics
Background:
- The subtribe Pleurothallidinae, a diverse orchid group, possesses a complex taxonomic history.
- Comparative plastome analysis offers insights into genome evolution and phylogenetic reconstruction.
Purpose of the Study:
- To investigate plastome evolution within the Pleurothallidinae subtribe.
- To identify candidate molecular markers for taxonomic and evolutionary studies.
Main Methods:
- Analysis of 25 complete chloroplast genomes from 15 Pleurothallidinae genera.
- Investigation of selection pressures on protein-coding genes and codon usage bias.
- Identification of hypervariable intergenic regions for molecular marker development.
Main Results:
- Conserved quadripartite plastome structure and gene content across analyzed genera.
- Detection of positive selection in specific lineages, such as ndhF in Lepanthes tachirensis.
- Identification of eight hypervariable intergenic regions suitable as molecular markers.
- Phylogenetic analysis indicating that Lepanthes and Pleurothallis are non-monophyletic.
Conclusions:
- Expanded plastome resources for Pleurothallidinae.
- Revealed lineage-specific selection patterns and codon usage bias.
- Provided valuable molecular markers for future orchid research.
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