73 researchers from 27 institutions, including the U.S. Department of Energy Joint Genome Institute (DOE JGI), collaborated to sequence and analyze the genomes and transcriptomes (the expressed genes) of two minute algae.
The ultimate goal was to understand secondary endosymbiosis, from which chloroplasts originally evolved, and why certain organisms contain nucleomorphs. The findings were published online November 29, 2012 in Nature.
Researchers determined these algae have a complex sub-cellular protein targeting machinery and four genomes derived from the two eukayotes that merged over time. Over half of the genes in the genomes are completely unique.
The head of the DOE JGI Fungal Genomics Program said he considers the two algae, B. natans and G. theta, to be living fossils that have the power to explain volumes about living organisms. The DOE is particularly interested in algae because of the practical applications in the fields of bioenergy and environment. In fact, the DOE JGI has published over 75% of the publicaly available algal genomes.
The findings published in Nature are important because they provide detailed information about how host and nucleomorph genomes were remodeled during evolution. Researchers have also discovered that nucleomorph-containing organisms are far more complicated than previously thought and their evolutionary history is quite complex that initially understood.
This research has illuminated the fundamental processes of cell symbiosis and genome reshaping that produced many of the most important organisms on the earth today. If we understand more about the origin of those organisms, we understand more about life, itself.