That’s what’s still going inside this food-poisoning bacteria, according to Science Daily. Its genetic material is so ancient, it’s older than genes as we know them:
In old textbooks, RNA was viewed simply as the chemical intermediary between DNA’s instruction manual and the creation of proteins. However, Breaker’s lab has identified the existence and function of riboswitches, or RNA structures that have the ability to detect molecules and control gene expression — an ability once believed to be possessed solely by proteins. Breaker and many other scientists now believe the first forms of life depended upon such RNA machines, which would have had to find ways to interact and carry out many of the functions proteins do today.
The new study, however, suggests that in the pathogenic stomach bacterium Clostridium difficile, this RNA structure acts as a sort of sensor to help regulate the expression of genes, probably to help the bacterium manipulate human cells.
“They were though to be molecular parasites, but it is clear they are being harnessed by cells to do some good for the organism,” Breaker said.
Not only ancient, but a cellular weapon.