0382165 - BC 2013 RIV GB eng J - Journal Article
Burki, F. - Flegontov, Pavel - Oborník, Miroslav - Cihlář, Jaromír - Pain, A. - Lukeš, Julius - Keeling, P. J.
Re-evaluating the green versus red signal in eukaryotes with secondary plastid of red algal origin.
Genome Biology and Evolution. Roč. 4, č. 6 (2012), s. 738-747. ISSN 1759-6653. E-ISSN 1759-6653
R&D Projects: GA ČR GAP506/12/1522; GA ČR GBP501/12/G055
Institutional support: RVO:60077344
Keywords : Endosymbiotic gene transfer * plastid evolution * protist * algae * chromera
Subject RIV: EB - Genetics ; Molecular Biology
Impact factor: 4.759, year: 2012 ; AIS: 2.278, rok: 2012
DOI: https://doi.org/10.1093/gbe/evs049

The transition from endosymbiont to organelle in eukaryotic cells involves the transfer of significant numbers of genes to the host genomes, a process known as endosymbiotic gene transfer (EGT). In the case of plastid organelles, EGTs have been shown to leave a footprint in the nuclear genome that can be indicative of ancient photosynthetic activity in present-day plastid-lacking organisms, or even hint at the existence of cryptic plastids. Here, we evaluated the impact of EGT on eukaryote genomes by reanalyzing the recently published EST dataset for Chromera velia, an interesting test case of a photosynthetic alga closely related to apicomplexan parasites. Previously, 513 genes were reported to originate from red and green algae in a 1:1 ratio. In contrast, by manually inspecting newly generated trees indicating putative algal ancestry, we recovered only 51 genes congruent with EGT, of which 23 and 9 were of red and green algal origin, respectively, whereas 19 were ambiguous regarding the algal provenance. Our approach also uncovered 109 genes that branched within a monocot angiosperm clade, most likely representing a contamination. We emphasize the lack of congruence and the subjectivity resulting from independent phylogenomic screens for EGT, which appear to call for extreme caution when drawing conclusions for major evolutionary events.
Permanent Link: http://hdl.handle.net/11104/0212464