Sequencing and phylogenetic analysis of chloroplast genes in freshwater raphidophytes

Research output: Contribution to journalArticle

Abstract

The complex evolution of chloroplasts in microalgae has resulted in highly diverse pigment profiles. Freshwater raphidophytes, for example, display a very different pigment composition to marine raphidophytes. To investigate potential differences in the evolutionary origin of chloroplasts in these two groups of raphidophytes, the plastid genomes of the freshwater species Gonyostomum semen and Vacuolaria virescens were sequenced. To exclusively sequence the organelle genomes, chloroplasts were manually isolated and amplified using single-cell whole-genome-amplification. Assembled and annotated chloroplast genes of the two species were phylogenetically compared to the marine raphidophyte Heterosigma akashiwo and other evolutionarily more diverse microalgae. These phylogenetic comparisons confirmed the high relatedness of all investigated raphidophyte species despite their large differences in pigment composition. Notable differences regarding the presence of light-independent protochlorophyllide oxidoreductase (LIPOR) genes among raphidophyte algae were also revealed in this study. The whole-genome amplification approach proved to be useful for isolation of chloroplast DNA from nuclear DNA. Although only approximately 50% of the genomes were covered, this was sufficient for a multiple gene phylogeny representing large parts of the chloroplast genes.

Details

Authors
Organisations
External organisations
  • University of the Littoral Opal Coast
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Genetics

Keywords

  • Chloroplast genome, LIPOR, Phylogeny, Raphidophytes, Whole-genome-amplification
Original languageEnglish
Article number245
JournalGenes
Volume10
Issue number3
Publication statusPublished - 2019 Mar 22
Publication categoryResearch
Peer-reviewedYes