The “RNA world” hypothesis proposes that the earliest life on Earth may have been based on RNA -; a single-stranded molecule similar in many ways to DNA -; like some modern viruses. This is because, like DNA, RNA can carry genetic information, but, like a protein, it can also act as an enzyme, initiating or accelerating reactions. While the activity of a few RNA enzymes -; called ribozymes -; have been tested on a case-by-case basis, there are thousands more that have been computationally predicted to exist in organisms ranging from bacteria to plants and animals. Now, a new method, developed by Penn State researchers, can test the activity of thousands of these predicted ribozymes in a single experiment.
The research team tested the activity of over 2,600 different RNA sequences predicted to belong to a class of RNA enzymes called “twister ribozymes,” which have the ability to cut themselves in two. Approximately 94% of the tested ribozymes were active, and the study revealed that their function can persist even when their structure contains slight imperfections. The research team also identified the first example of a twister ribozyme in mammals, specifically in the genome of the bottlenose dolphin.
A paper describing the study appeared online today, Nov. 5, in the journal Nucleic Acids Research.
“Whereas DNA is a double-stranded molecule that typically forms a simple helical structure, RNA is single stranded and can fold back on itself, forming diverse structures, including loops, bulges and helixes,” said Phil Bevilacqua, distinguished