Scientists link evolution to the ribosome

CHAMPAIGN, Ill., Aug. 21 (UPI) -- U.S. scientists say new analyses of cellular structures for making proteins -- the ribosome -- are consistent with a theory of life's early evolution.

The theory of life's early evolution states that life forms branched into three domains: bacteria, certain microbes and eukarya -- the domain that includes plants and humans. The theory was based on 1970s studies by University of Illinois Professor Carl Woese that found differences in the sequence of nucleotides in ribosomes.

In the current study, graduate student Elijah Roberts created computer programs that analyzed the three-dimensional sequence of nucleotides making up a cell's ribosome. He found most of the differences in nucleotide sequence between bacteria and microbes occurred in regions critical to ribosomal function.

"In that the ribosome constitutes the core of the cellular translation mechanism, which is the sine qua non of gene expression, which is the essence of life as we know it, these findings constitute a major step in understanding the evolution of life, which is still a journey of a thousand miles," said Woese, one of the new study's authors.

The research is reported in the Proceedings of the National Academy of Sciences.