@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 {leblond_galactolipids_2022,
	title = {Galactolipids of the genus Amphidinium (Dinophyceae): an hypothesis that they are basal to those of other peridinin-containing dinoflagellates},
	journal = {European Journal of Phycology},
	year = {2022},
	note = {Publisher: Taylor \& Francis _eprint: https://doi.org/10.1080/09670262.2022.2092215},
	pages = {1{\textendash}10},
	abstract = {The genus Amphidinium is shown in many phylogenies to be basal to other peridinin-containing, photosynthetic dinoflagellates as one of the first photosynthetic genera to arise after the evolution of heterotrophic genera. As part of our continuing examination of the plastid-associated galactolipids, namely mono- and digalactosyldiacylglycerol (MGDG and DGDG, respectively), in dinoflagellates, we here examine the galactolipid composition of members of the genus Amphidinium. We show that this genus is characterized by an abundance of 20:5(n-3)/18:5(n-3) and 20:5(n-3)/18:4(n-3) forms of MGDG and DGDG (with sn-1/sn-2 regiochemical specificity of fatty acids), but also sometimes with generally lesser amounts of some polyunsaturated C18/C18 forms, thus placing the examined species within a previously identified cluster of C20/C18 MGDG- and DGDG-containing, peridinin-containing dinoflagellates. We also show that Testudodinium testudo, previously known as Amphidinium testudo, conversely falls within a previously identified C18/C18 cluster, indicating a distinct difference in galactolipid biosynthesis capability. While it is likely that further revision of the genus may occur in the future and/or more basal peridinin-containing, photosynthetic genera may be discovered, at the current time Amphidinium is the currently agreed-upon most basal dinoflagellate genus for which isolates are available for biochemical characterization such as what we describe in this paper. Thus, because of the presumed basal position of the genus Amphidinium, we present a hypothesis that its galactolipids currently represent those that are ancestral to other genera of peridinin-containing dinoflagellates, including those within the C18/C18 cluster.},
	keywords = {Amphidinium, chloroplast, Dinoflagellate, Dinophyceae, lipid, RCC1981, Testudodinium},
	issn = {0967-0262},
	doi = {10.1080/09670262.2022.2092215},
	url = {https://doi.org/10.1080/09670262.2022.2092215},
	author = {Leblond, Jeffrey D. and Elkins, Lindsey C. and Graeff, Jori E. and Sabir, Kyra}
}
@article {Kayal2020,
	title = {Dinoflagellate host chloroplasts and mitochondria remain functional during amoebophrya infection},
	journal = {Frontiers in Microbiology},
	volume = {11},
	number = {December},
	year = {2020},
	note = {tex.mendeley-tags: RCC1627,RCC4398},
	month = {dec},
	pages = {1{\textendash}11},
	abstract = {Dinoflagellates are major components of phytoplankton that play critical roles in many microbial food webs, many of them being hosts of countless intracellular parasites. The phototrophic dinoflagellate Scrippsiella acuminata (Dinophyceae) can be infected by the microeukaryotic parasitoids Amoebophrya spp. (Syndiniales), some of which primarily target and digest the host nucleus. Early digestion of the nucleus at the beginning of the infection is expected to greatly impact the host metabolism, inducing the knockout of the organellar machineries that highly depend upon nuclear gene expression, such as the mitochondrial OXPHOS pathway and the plastid photosynthetic carbon fixation. However, previous studies have reported that chloroplasts remain functional in swimming host cells infected by Amoebophrya . We report here a multi-approach monitoring study of S. acuminata organelles over a complete infection cycle by nucleus-targeting Amoebophrya sp. strain A120. Our results show sustained and efficient photosystem II activity as a hallmark of functional chloroplast throughout the infection period despite the complete digestion of the host nucleus. We also report the importance played by light on parasite production, i.e., the amount of host biomass converted to parasite infective propagules. Using a differential gene expression analysis, we observed an apparent increase of all 3 mitochondrial and 9 out of the 11 plastidial genes involved in the electron transport chains (ETC) of the respiration pathways during the first stages of the infection. The longer resilience of organellar genes compared to those encoded by the nucleus suggests that both mitochondria and chloroplasts remain functional throughout most of the infection. This extended organelle functionality, along with higher parasite production under light conditions, suggests that host bioenergetic organelles likely benefit the parasite Amoebophrya sp. A120 and improve its fitness during the intracellular infective stage.},
	keywords = {amoebophrya, chloroplast, Dinoflagellate, frontiers in microbiology, frontiersin, kleptoplast, marine plankton, org, organelles, parasitism, RCC1627, RCC4398, www},
	issn = {1664-302X},
	doi = {10.3389/fmicb.2020.600823},
	url = {https://www.frontiersin.org/articles/10.3389/fmicb.2020.600823/full},
	author = {Kayal, Ehsan and Alves-de-Souza, Catharina and Farhat, Sarah and Velo-Suarez, Lourdes and Monjol, Joanne and Szymczak, Jeremy and Bigeard, Estelle and Marie, Dominique and Noel, Benjamin and Porcel, Betina M and Corre, Erwan and Six, Christophe and Guillou, Laure}
}
@article {Avilan2020,
	title = {ppGpp influences protein protection, growth and photosynthesis in Phaeodactylum tricornutum},
	journal = {bioRxiv},
	year = {2020},
	note = {Publisher: Cold Spring Harbor Laboratory tex.mendeley-tags: RCC2967},
	month = {mar},
	pages = {2020.03.05.978130},
	abstract = {{\textbullet} Chloroplasts retain elements of a bacterial stress response pathway that is mediated by the signalling nucleotides guanosine penta-and tetraphosphate, or (p)ppGpp. In the model flowering plant Arabidopsis, ppGpp acts as a potent regulator of plastid gene expression and influences photosynthesis, plant growth and development. However, little is known about ppGpp metabolism or its evolution in other photosynthetic eukaryotes. {\textbullet} Here, we studied the function of ppGpp in the diatom P. tricornutum using transgenic lines containing an inducible system for ppGpp accumulation. We used these lines to investigate the effects of ppGpp on growth, photosynthesis, lipid metabolism and protein expression. {\textbullet} We demonstrate that ppGpp accumulation reduces photosynthetic capacity and promotes a quiescent-like state with reduced proliferation and ageing. Strikingly, using non-targeted proteomics, we discovered that ppGpp accumulation also leads to the coordinated upregulation of a protein protection response in multiple cellular compartments. {\textbullet} Our findings highlight the importance of ppGpp as a fundamental regulator of chloroplast function across different domains of life, and lead to new questions about the molecular mechanisms and roles of (p)ppGpp signalling in photosynthetic eukaryotes.},
	keywords = {chloroplast, diatoms, lipid droplets, Phaeodactylum tricornutum, Photosynthesis, ppGpp, proteome, RCC2967},
	doi = {10.1101/2020.03.05.978130},
	url = {https://doi.org/10.1101/2020.03.05.978130},
	author = {Avilan, Luisana and Lebrun, Regine and Puppo, Carine and Citerne, Sylvie and Cuin{\'e}, Stephane and Li-Beisson, Yonghua and Menand, Benoit and Field, Ben and Gontero, Brigitte}
}
