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Title: Dinophysis, a highly specialized mixoplanktonic protist
SeveralDinophysisspecies produce lipophilic toxins (diarrhetic shellfish poisoning, DSP and pectenotoxins PTX) which are transferred through the food web. Even at low cell densities (< 103cell L-1), they can cause human illness and shellfish harvesting bans; toxins released into the water may kill early life stages of marine organisms.Dinophysisspecies are mixotrophs: they combine phototrophy (by means of kleptoplastids stolen from their prey) with highly selective phagotrophy on the ciliateMesodinium, also a mixotroph which requires cryptophyte prey of theTeleaulax/Geminigeraclade. Life cycle strategies, biological interactions and plastid acquisition and functioning inDinophysisspecies make them exemplars of resilient holoplanktonic mixoplankters and of ongoing speciation and plastidial evolution. Nevertheless, 17 years after the first successful culture was established, the difficulties in isolating and establishing cultures with local ciliate prey, the lack of robust molecular markers for species discrimination, and the patchy distribution of low-density populations in thin layers, hinder physiological experiments to obtain biological measurements of their populations and slow down potential advances with next-generation technologies. The Omic’s age inDinophysisresearch has only just started, but increased efforts need to be invested in systematic studies of plastidic diversity and culture establishment of ciliate and cryptophyte co-occurring withDinophysisin the same planktonic assemblages.  more » « less
Award ID(s):
2140395
PAR ID:
10534316
Author(s) / Creator(s):
; ; ; ; ; ;
Publisher / Repository:
Frontiers
Date Published:
Journal Name:
Frontiers in Protistology
Volume:
1
ISSN:
2813-849X
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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