Academic
Publications
A Tertiary Plastid Uses Genes from Two Endosymbionts

A Tertiary Plastid Uses Genes from Two Endosymbionts,10.1016/j.jmb.2006.01.084,Journal of Molecular Biology,Nicola J. Patron,Ross F. Waller,Patrick J.

A Tertiary Plastid Uses Genes from Two Endosymbionts   (Citations: 60)
BibTex | RIS | RefWorks Download
The origin and subsequent spread of plastids by endosymbiosis had a major environmental impact and altered the course of a great proportion of eukaryotic biodiversity. The ancestor of dinoflagellates contained a secondary plastid that was acquired in an ancient endosymbiotic event, where a eukaryotic cell engulfed a red alga. This is known as secondary endosymbiosis and has happened several times in eukaryotic evolution. Certain dinoflagellates, however, are unique in having replaced this secondary plastid in an additional (tertiary) round of endosymbiosis. Most plastid proteins are encoded in the nucleus of the host and are targeted to the organelle. When secondary or tertiary endosymbiosis takes place, it is thought that these genes move from nucleus to nucleus, so the plastid retains the same proteome. We have conducted large-scale expressed sequence tag (EST) surveys from Karlodinium micrum, a dinoflagellate with a tertiary haptophyte-derived plastid, and two haptophytes, Isochrysis galbana and Pavlova lutheri. We have identified all plastid-targeted proteins, analysed the phylogenetic origin of each protein, and compared their plastid-targeting transit peptides. Many plastid-targeted genes in the Karlodinium nucleus are indeed of haptophyte origin, but some genes were also retained from the original plastid (showing the two plastids likely co-existed in the same cell), in other cases multiple isoforms of different origins exist. We analysed plastid-targeting sequences and found the transit peptides in K. micrum are different from those found in either dinoflagellates or haptophytes, pointing to a plastid with an evolutionarily chimeric proteome, and a massive remodelling of protein trafficking during plastid replacement.
Journal: Journal of Molecular Biology - J MOL BIOL , vol. 357, no. 5, pp. 1373-1382, 2006
Cumulative Annual
View Publication
The following links allow you to view full publications. These links are maintained by other sources not affiliated with Microsoft Academic Search.
    • ...In K. brevis and K. micrum, dinoflagellates that have plastids derived from haptophytes, a large proportion of the nuclear-encoded plastid genes were derived from the plastid donor [54,55]...

    Jennifer H Wisecaveret al. Transcriptome analysis reveals nuclear-encoded proteins for the mainte...

    • ...Intriguingly, several algal lineages, such as the red algae Cyanidioschyzon merolae, the land plant Arabidopsis thaliana, various chromalveolates and the chlorarachniophyte Bigelowiella natans, seem to have nucleusencoded plastid-targeted protein genes originating from phylogenetically divergent algae [15,31-36]...
    • ...The level of plastid integration varies among dinoflagellates, ranging from fully integrated permanent plastid replacements such as the tertiary haptophyte-derived plastids found in Karenia and Karlodinium species [31] to less integrated plastids (i.e...
    • ...loss of all characters from the previous plastid as earlier predicted [31,48,49]...
    • ...The retention of “old” genes in the new plastid proteome mirrors the results of studies of the transcriptome of K. veneficum and K. brevis ,w hich harbor tertiary haptophyte-derived plastids [31,33]...
    • ...In K. veneficum, the apparent lack of peridinin-plastid derived photosynthesis genes suggests that its ancestor was heterotrophic when the new haptophyte plastid was acquired, and that the relic plastid was retained at that time for anabolic purposes [31]...
    • ...Horizontal or endosymbiotic gene transfer? The retention of nuclear-encoded genes from the peridinin-containing plastid in the L. chlorophorum plastid proteome is analogous with the situation in K. veneficum and K. brevis [31,33]...
    • ...The putative change of transit peptide characteristics is also seen in K. veneficum, whose transit signals are different from those of peridinin-containing plastids and those of haptophyte plastids [31]...
    • ...required a way to discriminate between the plastid genes [31]...

    Marianne A Mingeet al. A phylogenetic mosaic plastid proteome and unusual plastid-targeting s...

    • ...Perhaps the large-scale transfer of so many genes to the nucleus explains the apparent ease with which dinoflagellates can lose plastids and transiently or permanently acquire new ones (Saldarriaga et al., 2001; Green, 2004; Patron et al., 2006; Larkum et al., 2007)...

    Christopher J. Howeet al. The remarkable chloroplast genome of dinoflagellates

Sort by: