Environmental barcoding reveals massive dinoflagellate diversity in marine environments
Rowena F Stern1, Ales Horak, Rose L Andrew
1The Biodiversity Research Centre, University of British Columbia, Vancouver, British Columbia, Canada. rstern71@yahoo.com
Plos One
|November 19, 2010
Summary
DNA barcoding using the COI gene revealed massive natural diversity in dinoflagellates, with most environmental sequences not matching cultured species. This highlights our underestimation of microbial diversity.
Area of Science:
- Marine Biology
- Microbial Ecology
- Genetics
Background:
- Dinoflagellates are crucial marine protists with roles in primary production, coral symbiosis, and harmful algal blooms.
- Despite their ecological importance, the full natural diversity of dinoflagellates remains largely unknown.
- DNA barcoding offers a powerful tool for assessing microbial diversity.
Purpose of the Study:
- To establish a cytochrome c oxidase 1 (COI) barcode database for cultured dinoflagellates.
- To assess the effectiveness of COI barcoding for dinoflagellate species identification.
- To investigate the natural diversity of dinoflagellates in three distinct marine environments.
Main Methods:
- Assembled a global database of 336 COI barcodes from cultured dinoflagellates.
- Applied COI barcoding to environmental DNA samples from the Northeast Pacific, Northwest Atlantic, and Caribbean.
- Evaluated single-cell barcoding for identifying uncultivated dinoflagellate groups.
Main Results:
- COI barcoding successfully identified species in 70% of cultured dinoflagellate genera.
- The majority of environmental barcodes did not match known cultured species, indicating vast undiscovered diversity.
- Significant diversity was observed within the Kareniaceae family, previously thought to have modest species numbers.
- Only 51 out of 603 unique environmental barcodes could be linked to cultured species.
Conclusions:
- COI barcoding is effective for identifying dinoflagellate species and revealing hidden biodiversity.
- Environmental DNA sequencing demonstrates a massive underestimation of natural dinoflagellate diversity.
- Future research should focus on exploring these uncultivated dinoflagellate lineages.
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