@article {graeff_composition_2023,
	title = {Composition of galactolipids, betaine lipids and triglyceride-associated fatty acids of the symbiotic dinoflagellate Zooxanthella (Brandtodinium) nutricula: A glimpse into polyunsaturated fatty acids available to its polycystine radiolarian host},
	journal = {Phycological Research},
	volume = {n/a},
	number = {n/a},
	year = {2023},
	note = {_eprint: https://onlinelibrary.wiley.com/doi/pdf/10.1111/pre.12530},
	abstract = {<p>Zooxanthella nutricula is a photosynthetic dinoflagellate symbiont of polycystine radiolarians. As such, it is hypothesized to provide fixed organic carbon, including in the form of acylglycerolipids and sterols, to its non-photosynthetic host. We have previously characterized the sterols of Z. nutricula that may be transferred to its host and, in the present study, have turned our attention to three classes of fatty acid-containing lipids, chloroplast-associated galactolipids, betaine lipids, which are non-phosphorylated phospholipid analogs present in many eukaryotes, and triglycerides. Zooxanthella nutricula was observed using positive-ion electrospray/mass spectrometry (ESI/MS) and ESI/MS/MS to produce the galactolipids mono- and digalactosyldiacylglycerol (MGDG and DGDG, respectively) enriched in octadecapentaenoic (18:5(n-3)) and octadecatetraenoic (18:4(n-3)) acid to place it within a group of peridinin-containing dinoflagellates in a C18/C18 (sn-1/sn-2 fatty acid regiochemistry) cluster, as opposed to another cluster with C20/C18 MGDG and DGDG, where the C20 fatty acid is eicosapentaenoic acid (20:5(n-3)) and the C18 fatty acid is either 18:5(n-3) or 18:4(n-3). Zooxanthella nutricula was also observed to produce 38:10 (total number of fatty acid carbons:total number of double bonds), 38:6, and 44:7 diacylglycerylcarboxyhydroxymethylcholine (DGCC) as the sole type of betaine lipid. Although it is more difficult to determine which fatty acids are present in the sn-1 and sn-2 positions on the glycerol backbone of DGCC using ESI/MS/MS, gas chromatography/mass spectrometry (GC/MS)-based examination indicated the putatively DGCC-associated polyunsaturated fatty acid (PUFA) docosahexaenoic acid (22:6(n-3)). Coupled with the C18 PUFAs of MGDG and DGDG, and fatty acids associated with triglycerides (also examined via GC/MS), Z. nutricula could serve as a rich source of PUFAs for its radiolarian host. These data demonstrate that Z. nutricula produces a similar set of PUFA-containing lipids as Symbiodinium microadriaticum, a photosynthetic dinoflagellate symbiont of cnidarians, indicating a metabolic commonality in these phylogenetically discrete dinoflagellate symbionts with unrelated host organisms.</p>
},
	keywords = {Brandtodinium, chloroplast, Dinoflagellate, Dinophyceae, lipid, RCC3387, Zooxanthella},
	issn = {1440-1835},
	doi = {10.1111/pre.12530},
	url = {https://onlinelibrary.wiley.com/doi/abs/10.1111/pre.12530},
	author = {Graeff, Jori E. and Leblond, Jeffrey D.}
}
@article {yee_v-type_2023,
	title = {The V-type ATPase enhances photosynthesis in marine phytoplankton and further links phagocytosis to symbiogenesis},
	journal = {Current Biology},
	year = {2023},
	month = {may},
	pages = {S0960982223006152},
	abstract = {Diatoms, dinoflagellates, and coccolithophores are dominant groups of marine eukaryotic phytoplankton that are collectively responsible for the majority of primary production in the ocean.1 These phytoplankton contain additional intracellular membranes around their chloroplasts, which are derived from ancestral engulfment of red microalgae by unicellular heterotrophic eukaryotes that led to secondary and tertiary endosymbiosis.2 However, the selectable evolutionary advantage of these membranes and the physiological significance for extant phytoplankton remain poorly understood. Since intracellular digestive vacuoles are ubiquitously acidified by V-type H+-ATPase (VHA),3 proton pumps were proposed to acidify the microenvironment around secondary chloroplasts to promote the dehydration of dissolved inorganic carbon (DIC) into CO2, thus enhancing photosynthesis.4,5 We report that VHA is localized around the chloroplasts of centric diatoms and that VHA significantly contributes to their photosynthesis across a wide range of oceanic irradiances. Similar results in a pennate diatom, dinoflagellate, and coccolithophore, but not green or red microalgae, imply the co-option of phagocytic VHA activity into a carbon-concentrating mechanism (CCM) is common to secondary endosymbiotic phytoplankton. Furthermore, analogous mechanisms in extant photosymbiotic marine invertebrates6{\textendash}8 provide functional evidence for an adaptive advantage throughout the transition from endosymbiosis to symbiogenesis. Based on the contribution of diatoms to ocean biogeochemical cycles, VHA-mediated enhancement of photosynthesis contributes at least 3.5 Gtons of fixed carbon per year (or 7\% of primary production in the ocean), providing an example of a symbiosis-derived evolutionary innovation with global environmental implications.},
	keywords = {RCC3387},
	issn = {09609822},
	doi = {10.1016/j.cub.2023.05.020},
	url = {https://linkinghub.elsevier.com/retrieve/pii/S0960982223006152},
	author = {Yee, Daniel P. and Samo, Ty J. and Abbriano, Raffaela M. and Shimasaki, Bethany and Vernet, Maria and Mayali, Xavier and Weber, Peter K. and Mitchell, B. Greg and Hildebrand, Mark and Decelle, Johan and Tresguerres, Martin}
}
@article {graeff_sterol_2021,
	title = {Sterol Composition of the Peridinioid Dinoflagellate Zooxanthella nutricula, A Symbiont of Polycystine Radiolarians},
	journal = {Protist},
	volume = {172},
	number = {3},
	year = {2021},
	month = {jul},
	pages = {125817},
	abstract = {Some dinoflagellates, such as Symbiodinium, are able to form symbiotic relationships with larger marine organisms. An important aspect of dinoflagellate symbiosis involves the exchange of lipids, namely sterols, from the symbiont to the host. Much research has explored the lipid biochemistry of the symbiotic relationship between cnidarians and Symbiodinium dinoflagellates. However, no research has addressed the sterol biochemistry of the symbiosis between radiolarians and dinoflagellates such as Zooxanthella nutricula. To this end, we have provided the first sterol characterization of Z. nutricula isolated from a spumellarian polycystine radiolarian. Fifteen sterols and one steroidal ketone were observed where the major sterol identified was C27 22-dehydrocholesterol, which does not tend to be a dominant sterol among dinoflagellates, including closely related peridinioid species in the genus Heterocapsa. However, C30 dinosterol and dinostanol were major sterols in both Z. nutricula and Heterocapsa spp., thus indicating common sterols between closely related taxa. Major sterols of the distantly related genus Symbiodinium, a symbiont of foraminifera and cnidarians, have included C27 cholesterol and C30 gorgosterol, whereas in Z. nutricula these sterols were minor and absent, respectively. Our results indicate potentially different sterol pools available to cnidarian and radiolarian symbiont hosts during their respective relationships with symbiotic dinoflagellates.},
	keywords = {Dinoflagellate, lipid, Peridiniales, Radiolaria, rcc, RCC3387, sterol},
	issn = {1434-4610},
	doi = {10.1016/j.protis.2021.125817},
	url = {https://www.sciencedirect.com/science/article/pii/S1434461021000262},
	author = {Graeff, Jori E. and Leblond, Jeffrey D.}
}
@article {Liu2019,
	title = {Transcriptome of thalassicolla nucleata holobiont reveals details of a radiolarian symbiotic relationship},
	journal = {Frontiers in Marine Science},
	volume = {6},
	number = {June},
	year = {2019},
	note = {tex.mendeley-tags: RCC3387},
	month = {jun},
	pages = {1{\textendash}11},
	keywords = {Brandtodinium, holobiont, photosymbiosis, radiolarian, RCC3387, Transcriptome},
	issn = {2296-7745},
	doi = {10.3389/fmars.2019.00284},
	url = {https://www.frontiersin.org/article/10.3389/fmars.2019.00284/full},
	author = {Liu, Zhenfeng and Mesrop, Lisa Y. and Hu, Sarah K. and Caron, David A.}
}
@article {Meng2018,
	title = {Analysis of the genomic basis of functional diversity in dinoflagellates using a transcriptome-based sequence similarity network},
	journal = {Molecular Ecology},
	year = {2018},
	note = {tex.mendeley-tags: RCC1491,RCC1516,RCC3387,RCC3468,RCC3507},
	pages = {0{\textendash}2},
	abstract = {Dinoflagellates are one of the most abundant and functionally diverse groups of eukaryotes. Despite an overall scarcity of genomic information for dinoflagellates, constantly emerging high-throughput sequencing resources can be used to characterize and compare these organisms. We assembled de novo and processed 46 dinoflagellate transcriptomes and used a sequence similarity network (SSN) to compare the underlying genomic basis of functional features within the group. This approach constitutes the most comprehensive picture to date of the genomic potential of dinoflagellates. A core predicted proteome composed of 252 connected components (CCs) of putative conserved protein domains (pCDs) was identified. Of these, 206 were novel and 16 lacked any functional annotation in public databases. Integration of functional information in our network analyses allowed investigation of pCDs specifically associated to functional traits. With respect to toxicity, sequences homologous to those of proteins found in species with toxicity potential (e.g. sxtA4 and sxtG) were not specific to known toxin-producing species. Although not fully specific to symbiosis, the most represented functions associated with proteins involved in the symbiotic trait were related to membrane processes and ion transport. Overall, our SSN approach led to identification of 45,207 and 90,794 specific and constitutive pCDs of respectively the toxic and symbiotic species represented in our analyses. Of these, 56\% and 57\% respectively (i.e. 25,393 and 52,193 pCDs) completely lacked annotation in public databases. This stresses the extent of our lack of knowledge, while emphasizing the potential of SSNs to identify candidate pCDs for further functional genomic characterization. This article is protected by copyright. All rights reserved.},
	keywords = {Genomics/Proteomics, Microbial Biology, Molecular Evolution, Protists, rcc1491, RCC1516, RCC3387, rcc3468, rcc3507, transcriptomics},
	issn = {09621083},
	doi = {10.1111/mec.14579},
	url = {http://www.ncbi.nlm.nih.gov/pubmed/29624751\%0Ahttp://doi.wiley.com/10.1111/mec.14579},
	author = {Meng, Arnaud and Corre, Erwan and Probert, Ian and Gutierrez-Rodriguez, Andres and Siano, Raffaele and Annamale, Anita and Alberti, Adriana and Da Silva, Corinne and Wincker, Patrick and Le Crom, St{\'e}phane and Not, Fabrice and Bittner, Lucie}
}
@article {Probert2014a,
	title = {Brandtodinium gen. nov. and B. nutricula comb. Nov. (Dinophyceae), a dinoflagellate commonly found in symbiosis with polycystine radiolarians},
	journal = {Journal of Phycology},
	volume = {50},
	number = {2},
	year = {2014},
	note = {tex.mendeley-tags: RCC3378,RCC3379,RCC3380,RCC3381,RCC3382,RCC3383,RCC3384,RCC3385,RCC3386,RCC3387,RCC3388},
	pages = {388{\textendash}399},
	abstract = {Symbiotic interactions between pelagic hosts and microalgae have received little attention, although they are widespread in the photic layer of the world ocean, where they play a fundamental role in the ecology of the planktonic ecosystem. Polycystine radiolarians (including the orders Spumellaria, Collodaria and Nassellaria) are planktonic heterotrophic protists that are widely distributed and often abundant in the ocean. Many polycystines host symbiotic microalgae within their cytoplasm, mostly thought to be the dinoflagellate Scrippsiella nutricula, a species originally described by Karl Brandt in the late nineteenth century as Zooxanthella nutricula. The free-living stage of this dinoflagellate has never been characterized in terms of morphology and thecal plate tabulation. We examined morphological characters and sequenced conservative ribosomal markers of clonal cultures of the free-living stage of symbiotic dinoflagellates isolated from radiolarian hosts from the three polycystine orders. In addition, we sequenced symbiont genes directly from several polycystine-symbiont holobiont specimens from different oceanic regions. Thecal plate arrangement of the free-living stage does not match that of Scrippsiella or related genera, and LSU and SSU rDNA-based molecular phylogenies place these symbionts in a distinct clade within the Peridiniales. Both phylogenetic analyses and the comparison of morphological features of culture strains with those reported for other closely related species support the erection of a new genus that we name Brandtodinium gen. nov. and the recombination of S. nutricula as B. nutricula comb. nov.},
	keywords = {Dinoflagellate, MACUMBA, Peridiniales, polycystines, Radiolaria, rcc, RCC3378, RCC3379, RCC3380, RCC3381, RCC3382, RCC3383, RCC3384, RCC3385, RCC3386, RCC3387, RCC3388, SBR$_\textrmP$hyto$_\textrmD$PO, Scrippsiella, symbiosis, taxonomy, Zooxanthella},
	doi = {10.1111/jpy.12174},
	url = {http://dx.doi.org/10.1111/jpy.12174},
	author = {Probert, Ian and Siano, Raffaele and Poirier, Camille and Decelle, Johan and Biard, Tristan and Tuji, Akihiro and Suzuki, Noritoshi and Not, Fabrice}
}
