Sunday, September 17, 2006
Plastids are the photo-synthetic engines in all algae and plants, and their origin and spread among eukaryotes, ultimately giving rise to land plants, was fundamental to the evolution of plants and animals on our planet. Plastids, which possess genomes that are distinct from the primary, nuclear genomes of cells, are thought to have arisen from so-called endosymbiosis, in which a cyano-bacterium is captured by another cell, leading the conversion of the cyanobacterium to a plastid organelle that is an essential constituent of a eukaryotic cell.
By analyzing DNA sequences contained in the plastid of the thecate amoeba Paulinella, researchers have shown that it is a recent endosymbiont whose genome features are virtually unchanged from those of its cyano-bacterial progenitor. The findings, which help elucidate how plastid organelles arise from endo-symbiosis, are reported by Debashish Bhattacharya and colleagues at the University of Iowa and appear in the September 5th (2006) issue of Current Biology, published by Cell Press.
Based on "Minimal plastid genome evolution in the Paulinella endosymbiont" - no Abstract available but the full text can currently be downloaded as a pdf file from here.
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