AUTHOR=Hansen Per J. , Ojamäe Karin , Berge Terje , Trampe Erik C. L. , Nielsen Lasse T. , Lips Inga , Kühl Michael 

TITLE=Photoregulation in a Kleptochloroplastidic Dinoflagellate, Dinophysis acuta

JOURNAL=Frontiers in Microbiology

VOLUME=7

YEAR=2016

URL=https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2016.00785

DOI=10.3389/fmicb.2016.00785

ISSN=1664-302X

ABSTRACT=<p>Some phagotrophic organisms can retain chloroplasts of their photosynthetic prey as so-called kleptochloroplasts and maintain their function for shorter or longer periods of time. Here we show for the first time that the dinoflagellate <italic>Dinophysis acuta</italic> takes control over “third-hand” chloroplasts obtained from its ciliate prey <italic>Mesodinium</italic> spp. that originally ingested the cryptophyte chloroplasts. With its kleptochloroplasts, <italic>D. acuta</italic> can synthesize photosynthetic as well as photoprotective pigments under long-term starvation in the light. Variable chlorophyll fluorescence measurements showed that the kleptochloroplasts were fully functional during 1 month of prey starvation, while the chlorophyll <italic>a</italic>-specific inorganic carbon uptake decreased within days of prey starvation under an irradiance of 100 μmol photons m<sup>-2</sup> s<sup>-1</sup>. While <italic>D. acuta</italic> cells can regulate their pigmentation and function of kleptochloroplasts they apparently lose the ability to maintain high inorganic carbon fixation rates.</p>