Algal genomes reveal evolutionary mosaicism and the fate of nucleomorphs

@article{Curtis2012AlgalGR,
  title={Algal genomes reveal evolutionary mosaicism and the fate of nucleomorphs},
  author={Bruce A. Curtis and Goro Tanifuji and Fabien Burki and Ansgar Gruber and Manuel Irimia and Shinichiro Maruyama and Maria Cecilia Arias and Steven G Ball and Gillian H. Gile and Yoshihisa Hirakawa and Julia F. Hopkins and Alan Kuo and Stefan Andreas Rensing and Jeremy Schmutz and Aikaterini Symeonidi and Marek Eli{\'a}{\vs} and Robert Jm Eveleigh and Emily K. Herman and Mary J. Klute and Takuro Nakayama and Miroslav Oborn{\'i}k and Adri{\'a}n Reyes-Prieto and E. Virginia Armbrust and Stephen J Aves and Robert G. Beiko and Pedro M. Coutinho and Joel B. Dacks and Dion G Durnford and Naomi M. Fast and Beverley R. Green and Cameron J. Grisdale and Franziska Hempel and Bernard Henrissat and Marc P. H{\"o}ppner and Ken-Ichiro Ishida and Eunsoo Kim and Ludek Koreny and Peter G. Kroth and Yuan Liu and Shehre-Banoo Malik and Uwe G. Maier and Darcy L. McRose and Thomas Mock and Jonathan A. D. Neilson and Naoko T. Onodera and Anthony M. Poole and Ellen J. Pritham and Thomas A. Richards and Gabrielle Rocap and Scott William Roy and Chihiro Sarai and Sarah Schaack and Shu Shirato and Claudio H. Slamovits and D. F. Spencer and Shigekatsu Suzuki and Alexandra Z. Worden and Stefan Zauner and Kerrie W. Barry and Callum J. Bell and Arvind Kumar Bharti and John Allen Crow and Jane Grimwood and Robin Kramer and Erika A. Lindquist and Susan M. Lucas and Asaf A. Salamov and Geoffrey Ian McFadden and Christopher E. Lane and Patrick J. Keeling and Michael W. Gray and Igor V. Grigoriev and John M. Archibald},
  journal={Nature},
  year={2012},
  volume={492},
  pages={59-65}
}
Cryptophyte and chlorarachniophyte algae are transitional forms in the widespread secondary endosymbiotic acquisition of photosynthesis by engulfment of eukaryotic algae. Unlike most secondary plastid-bearing algae, miniaturized versions of the endosymbiont nuclei (nucleomorphs) persist in cryptophytes and chlorarachniophytes. To determine why, and to address other fundamental questions about eukaryote–eukaryote endosymbiosis, we sequenced the nuclear genomes of the cryptophyte Guillardia theta… 

Polyploidy of Endosymbiotically Derived Genomes in Complex Algae

Chlorarachniophyte and cryptophyte algae have complex plastids that were acquired by the uptake of a green or red algal endosymbiont via secondary endosymbiosis. The plastid is surrounded by four

Nucleomorph Comparative Genomics

The current state of knowledge of nucleomorphic genome biology is reviewed, focusing on the evolution, diversity, and function of nucleomorphs in the two lineages that bear them.

Endosymbiotic Gene Transfer in the Nucleomorph containing organisms Bigelowiella natans and Guillardia theta

To understand the process of EGT and endosymbiosis in general, the nuclear genomes of the cryptophyte Guillardia theta and the chlorarachniophyte Bigelowiella natans were sequenced and nuclear genes whose encoded proteins appear to function in the mitochondrion were investigated.

Diurnal Transcriptional Regulation of Endosymbiotically Derived Genes in the Chlorarachniophyte Bigelowiella natans

The results of this study suggest that nucleomorph genes have lost transcriptional regulation along the diurnal cycles, and nuclear genes exert control over the complex plastid including the nucleomorph.

Comparative genomics of mitochondria in chlorarachniophyte algae: endosymbiotic gene transfer and organellar genome dynamics

The results suggest that chlorarachniophyte mtDNAs are more evolutionarily dynamic than their plastid counterpart, despite being of similar size and coding capacity.

Algal endosymbionts as vectors of horizontal gene transfer in photosynthetic eukaryotes

The idea that Plantae (in particular red algae) are one of the major players in eukaryote genome evolution by virtue of their ability to act as "sinks" and "sources" of foreign genes through HGT and endosymbiosis, respectively is discussed.

PolyploidyofEndosymbioticallyDerivedGenomes inComplex Algae

Chlorarachniophyte and cryptophyte algae have complex plastids that were acquired by the uptake of a green or red algal endosymbiont via secondary endosymbiosis. The plastid is surrounded by four

Nucleomorph Genome Sequences of Two Chlorarachniophytes, Amorphochlora amoebiformis and Lotharella vacuolata

Comparative analyses among four chlorarachniophyte nucleomorph genomes revealed that these sequences share 171 function-predicted genes, including the same set of genes encoding 17 plastid-associated proteins, and no evidence of a recent nucleomorph-to-nucleus gene transfer was found, suggesting that chlorarchniophytes nucleomorph genome underwent most of their reductive evolution prior to the radiation of extent members of the group.

Evolutionary Dynamics of Cryptophyte Plastid Genomes

A comparative analysis of plastid genomes from six representative cryptophyte genera reveals examples of gene loss and intron insertion in cryptophytes, and the chlB/chlL/ chlN genes, which encode light-independent (dark active) protochlorophyllide oxidoreductase (LIPOR) proteins have undergone recent gene loss, pseudogenization, and pseudogenized in Cryptomonas paramecium.

Regulation of chloroplast and nucleomorph replication by the cell cycle in the cryptophyte Guillardia theta

The results of this study and previous studies on chlorarachniophytes suggest that there was a common evolutionary pattern in which an endosymbiont lost its replication cycle- dependent transcription while cell-cycle-dependent transcriptional regulation of host nuclear genes came to restrict the timing of nucleomorph replication and chloroplast division.
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