Using information held in the cells of each of Earth's life forms, scientists from the Georgia Institute of Technology are tracing the evolution of life all the way back to 3.8 million years ago. Their study outlines the importance of the ribosome, one of the oldest building blocks of life, and its ability to provide insights into the biological processes that occurred at the root of the "Tree of Life."
"Biology is a great keeper of records," Loren Williams, who headed the research, said in a press release. "We are figuring out how to read some of the oldest records in biology to understand pre-biological processes, the origin of life, and the evolution of life on Earth."
Although ribosomes remain integral to modern organisms, they contain components that were important in the functioning of some of Earth's earliest organisms, with a common core that can be seen in all life forms.
"The ribosome recorded its history," said Williams. "It accreted and got bigger and bigger over time. But the older parts were continually frozen after they accreted, just like the rings of a tree. As long as that tree lives, the inner rings will not change. The very core of the ribosome is older than biology, produced by evolutionary processes that we still don't understand very well."
Despite this similarity, there are many additions that have been made over the years - for example, human ribosomes are the largest in the world and have approximately 7,000 nucleotides, a big change from the 100 or so that were present in the earliest organisms.
Using the knowledge from this research, scientists will not only be able to better understand evolution but also antibiotic treatment.
"The ribosome is one of the primary [sic] target for antibiotics, so understanding its architecture and consistently throughout biology could be of great benefit," said Williams. "By studying the ribosome, we can start thinking about biology in a different way. We can see the symbiotic relationship between RNA and proteins."
The next step for Williams and his team is to continue running experiments that further support their current model. "We have a coherent and consistent model that accounts for all the data we have going all the way back to a form of biology that is very primitive compared to what we have now," he said. "We plan to continue testing the predictions of the model."
