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Updated: Jul 17, 2026
08:57
Using Phylogenetic Analysis to Investigate Eukaryotic Gene Origin
Published on: August 14, 2018
Phylogeny of phagotrophic euglenids (Euglenozoa) as inferred from hsp90 gene sequences
Susana A Breglia1, Claudio H Slamovits, Brian S Leander
1Program in Evolutionary Biology, Department of Botany, Canadian Institute for Advanced Research, University of British Columbia, Vancouver, BC, Canada V6T 1Z4.
The Journal of Eukaryotic Microbiology
|February 16, 2007
Summary
This study used the heat-shock protein 90 gene (hsp90) to resolve deep euglenid phylogeny. Results clarify relationships within Euglenozoa, placing Petalomonas cantuscygni as basal, but highlight the need for further mitochondrial genome research.
Area of Science:
- * Protistology and Molecular Evolution
- * Eukaryotic Phylogenetics
Background:
- * Ribosomal RNA genes have limitations in resolving deep evolutionary relationships within euglenids.
- * The heat-shock protein 90 (hsp90) gene is a valuable tool for eukaryotic phylogenetics.
Purpose of the Study:
- * To investigate the deep phylogeny of euglenids using the hsp90 gene.
- * To clarify the evolutionary relationships among major euglenid lineages and their placement within Euglenozoa.
Main Methods:
- * Sequencing of the cytosolic hsp90 gene from three euglenid taxa: Petalomonas cantuscygni, Entosiphon sulcatum, and Peranema trichophorum.
- * Phylogenetic analyses utilizing hsp90 sequences, with careful consideration of outgroup selection (Reclinomonas americana).
- * Analysis of intron structure in the hsp90 gene of P. trichophorum.
Main Results:
- * Phylogenetic analyses confirmed a closer relationship between kinetoplastids and diplonemids than to euglenids.
- * The study supported existing views on the branching order of bacteriovorous, eukaryovorous, and photosynthetic euglenids.
- * Robust phylogenies, using R. americana as an outgroup, positioned P. cantuscygni as the most basal euglenid lineage.
Conclusions:
- * The hsp90 gene provides better resolution for deep euglenid phylogeny than rRNA genes.
- * The basal position of P. cantuscygni is robustly supported, though its mitochondrial inclusion warrants further investigation.
- * Further research into the mitochondrial genomes of euglenids and diplonemids is necessary to refine phylogenetic understanding.
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