@article {benites_evolutionary_2021,
	title = {Evolutionary Genomics of Sex-Related Chromosomes at the Base of the Green Lineage},
	journal = {Genome Biology and Evolution},
	volume = {13},
	number = {10},
	year = {2021},
	pages = {evab216},
	abstract = {Although sex is now accepted as a ubiquitous and ancestral feature of eukaryotes, direct observation of sex is still lacking in most unicellular eukaryotic lineages. Evidence of sex is frequently indirect and inferred from the identification of genes involved in meiosis from whole genome data and/or the detection of recombination signatures from genetic diversity in natural populations. In haploid unicellular eukaryotes, sex-related chromosomes are named mating-type (MTs) chromosomes and generally carry large genomic regions where recombination is suppressed. These regions have been characterized in Fungi and Chlorophyta and determine gamete compatibility and fusion. Two candidate MT{\th} and MT{\`A} alleles, spanning 450{\textendash}650 kb, have recently been described in Ostreococcus tauri, a marine phytoplanktonic alga from the Mamiellophyceae class, an early diverging branch in the green lineage. Here, we investigate the architecture and evolution of these candidate MT{\th} and MT{\`A} alleles. We analyzed the phylogenetic profile and GC content of MT gene families in eight different genomes whose divergence has been previously estimated at up to 640 Myr, and found evidence that the divergence of the two MT alleles predates speciation in the Ostreococcus genus. Phylogenetic profiles of MT transspecific polymorphisms in gametologs disclosed candidate MTs in two additional species, and possibly a third. These Mamiellales MT candidates are likely to be the oldest mating-type loci described to date, which makes them fascinating models to investigate the evolutionary mechanisms of haploid sex determination in eukaryotes.},
	keywords = {RCC1105, RCC1115, RCC2590, RCC299, rcc3401, RCC4221, RCC809, RCC834},
	issn = {1759-6653},
	doi = {10.1093/gbe/evab216},
	url = {https://academic.oup.com/gbe/article/doi/10.1093/gbe/evab216/6380139},
	author = {Benites, Luis Felipe and Bucchini, Fran{\c c}ois and Sanchez-Brosseau, Sophie and Grimsley, Nigel and Vandepoele, Klaas and Piganeau, Gwenael},
	editor = {Wolfe, Kenneth}
}
@article {castillo_seasonal_2021,
	title = {Seasonal dynamics of natural Ostreococcus viral infection at the single cell level using VirusFISH},
	journal = {Environmental Microbiology},
	volume = {n/a},
	number = {n/a},
	year = {2021},
	note = {_eprint: https://onlinelibrary.wiley.com/doi/pdf/10.1111/1462-2920.15504},
	abstract = {Ostreococcus is a cosmopolitan marine genus of phytoplankton found in mesotrophic and oligotrophic waters, and the smallest free-living eukaryotes known to date, with a cell diameter close to 1 μm. Ostreococcus has been extensively studied as a model system to investigate viral{\textendash}host dynamics in culture, yet the impact of viruses in naturally occurring populations is largely unknown. Here, we used Virus Fluorescence in situ Hybridization (VirusFISH) to visualize and quantify viral-host dynamics in natural populations of Ostreococcus during a seasonal cycle in the central Cantabrian Sea (Southern Bay of Biscay). Ostreococcus were predominantly found during summer and autumn at surface and 50 m depth, in coastal, mid-shelf and shelf waters, representing up to 21\% of the picoeukaryotic communities. Viral infection was only detected in surface waters, and its impact was variable but highest from May to July and November to December, when up to half of the population was infected. Metatranscriptomic data available from the mid-shelf station unveiled that the Ostreococcus population was dominated by the species O. lucimarinus. This work represents a proof of concept that the VirusFISH technique can be used to quantify the impact of viruses on targeted populations of key microbes from complex natural communities. This article is protected by copyright. All rights reserved.},
	keywords = {RCC2590, RCC4221, RCC809},
	issn = {1462-2920},
	doi = {10.1111/1462-2920.15504},
	url = {http://sfamjournals.onlinelibrary.wiley.com/doi/abs/10.1111/1462-2920.15504},
	author = {Castillo, Yaiza M. and Forn, Irene and Yau, Sheree and Mor{\'a}n, Xos{\'e} Anxelu G. and Alonso-S{\'a}ez, Laura and Arandia-Gorostidi, N{\'e}stor and Vaqu{\'e}, Dolors and Sebasti{\'a}n, Marta}
}
@article {Leconte2020,
	title = {Genome resolved biogeography of mamiellales},
	journal = {Genes},
	volume = {11},
	number = {1},
	year = {2020},
	note = {tex.mendeley-tags: RCC1105,RCC299,RCC4221: RCC2590,RCC809},
	month = {jan},
	pages = {66},
	abstract = {Among marine phytoplankton, Mamiellales encompass several species from the genera Micromonas, Ostreococcus and Bathycoccus, which are important contributors to primary production. Previous studies based on single gene markers described their wide geographical distribution but led to discussion because of the uneven taxonomic resolution of the method. Here, we leverage genome sequences for six Mamiellales species, two from each genus Micromonas, Ostreococcus and Bathycoccus, to investigate their distribution across 133 stations sampled during the Tara Oceans expedition. Our study confirms the cosmopolitan distribution of Mamiellales and further suggests non-random distribution of species, with two triplets of co-occurring genomes associated with different temperatures: Ostreococcus lucimarinus, Bathycoccus prasinos and Micromonas pusilla were found in colder waters, whereas Ostreococcus spp. RCC809, Bathycoccus spp. TOSAG39-1 and Micromonas commoda were more abundant in warmer conditions. We also report the distribution of the two candidate mating-types of Ostreococcus for which the frequency of sexual reproduction was previously assumed to be very low. Indeed, both mating types were systematically detected together in agreement with either frequent sexual reproduction or the high prevalence of a diploid stage. Altogether, these analyses provide novel insights into Mamiellales{\textquoteright} biogeography and raise novel testable hypotheses about their life cycle and ecology.},
	keywords = {Biogeography, mamiellales, mating-type, RCC1105, RCC2590, RCC299, RCC4221, RCC809, sexual reproduction, tara oceans},
	issn = {2073-4425},
	doi = {10.3390/genes11010066},
	url = {https://www.mdpi.com/2073-4425/11/1/66},
	author = {Leconte and Benites and Vannier and Wincker and Piganeau and Jaillon}
}
@article {Yau2020,
	title = {Virus-host coexistence in phytoplankton through the genomic lens},
	journal = {Science Advances},
	volume = {6},
	number = {14},
	year = {2020},
	note = {tex.mendeley-tags: RCC2590,RCC2596},
	month = {apr},
	pages = {eaay2587},
	abstract = {Virus-microbe interactions in the ocean are commonly described by {\textquotedblleft}boom and bust{\textquotedblright} dynamics, whereby a numerically dominant microorganism is lysed and replaced by a virus-resistant one. Here, we isolated a microalga strain and its infective dsDNA virus whose dynamics are characterized instead by parallel growth of both the microalga and the virus. Experimental evolution of clonal lines revealed that this viral production originates from the lysis of a minority of virus-susceptible cells, which are regenerated from resistant cells. Whole-genome sequencing demonstrated that this resistant-susceptible switch involved a large deletion on one chromosome. Mathematical modeling explained how the switch maintains stable microalga-virus population dynamics consistent with their observed growth pattern. Comparative genomics confirmed an ancient origin of this {\textquotedblleft}accordion{\textquotedblright} chromosome despite a lack of sequence conservation. Together, our results show how dynamic genomic rearrangements may account for a previously overlooked coexistence mechanism in microalgae-virus interactions.},
	keywords = {RCC2590, RCC2596},
	issn = {2375-2548},
	doi = {10.1126/sciadv.aay2587},
	url = {https://advances.sciencemag.org/lookup/doi/10.1126/sciadv.aay2587},
	author = {Yau, Sheree and Krasovec, Marc and Benites, L. Felipe and Rombauts, Stephane and Groussin, Mathieu and Vancaester, Emmelien and Aury, Jean-Marc and Derelle, Evelyne and Desdevises, Yves and Escande, Marie-Line and Grimsley, Nigel and Guy, Julie and Moreau, Herv{\'e} and Sanchez-Brosseau, Sophie and Van de Peer, Yves and Vandepoele, Klaas and Gourbi{\`e}re, S{\'e}bastien and Piganeau, Gwenael}
}
@article {Subirana2013,
	title = {Morphology, genome plasticity, and phylogeny in the genus ostreococcus reveal a cryptic species, o. mediterraneus sp. nov. (mamiellales, mamiellophyceae)},
	journal = {Protist},
	volume = {164},
	number = {5},
	year = {2013},
	note = {tex.mendeley-tags: RCC1112,RCC1114,RCC1117,RCC143,RCC1620,RCC1621,RCC1623,RCC1624,RCC2572,RCC2573,RCC2574,RCC2575,RCC2577,RCC2578,RCC2579,RCC2582,RCC2583,RCC2584,RCC2585,RCC2587,RCC2590,RCC344,RCC356,RCC393,RCC501,RCC745,RCC809},
	pages = {643{\textendash}659},
	abstract = {Coastal marine waters in many regions worldwide support abundant populations of extremely small (1-3 ??m diameter) unicellular eukaryotic green algae, dominant taxa including several species in the class Mamiellophyceae. Their diminutive size conceals surprising levels of genetic diversity and defies classical species{\textquoteright} descriptions. We present a detailed analysis within the genus Ostreococcus and show that morphological characteristics cannot be used to describe diversity within this group. Karyotypic analyses of the best-characterized species O. tauri show it to carry two chromosomes that vary in size between individual clonal lines, probably an evolutionarily ancient feature that emerged before species{\textquoteright} divergences within the Mamiellales. By using a culturing technique specifically adapted to members of the genus Ostreococcus, we purified {\textquestiondown}30 clonal lines of a new species, Ostreococcus mediterraneus sp. nov., previously known as Ostreococcus clade D, that has been overlooked in several studies based on PCR-amplification of genetic markers from environment-extracted DNA. Phylogenetic analyses of the S-adenosylmethionine synthetase gene, and of the complete small subunit ribosomal RNA gene, including detailed comparisons of predicted ITS2 (internal transcribed spacer 2) secondary structures, clearly support that this is a separate species. In addition, karyotypic analyses reveal that the chromosomal location of its ribosomal RNA gene cluster differs from other Ostreococcus clades.},
	keywords = {barcode, Chromosome, culture, ITS2, karyotype, picoeukaryote, rcc, RCC1112, RCC1114, RCC1117, RCC143, RCC1620, RCC1621, RCC1623, RCC1624, RCC2572, RCC2573, RCC2574, RCC2575, RCC2577, RCC2578, RCC2579, RCC2582, RCC2583, RCC2584, RCC2585, RCC2587, RCC2590, RCC344, RCC356, RCC393, rcc501, RCC745, RCC809, ribosomal gene},
	doi = {10.1016/j.protis.2013.06.002},
	url = {http://www.sciencedirect.com/science/article/pii/S1434461013000497},
	author = {Subirana, Lucie and P{\'e}quin, B{\'e}rang{\`e}re and Michely, St{\'e}phanie and Escande, Marie-Line and Meilland, Julie and Derelle, Evelyne and Marin, Birger and Piganeau, Gwenael and Desdevises, Yves and Moreau, Herv{\'e} and Grimsley, Nigel H}
}
