The Exosome: RNA Degradation and Evolution

“When the cell makes a copy of a segment of DNA the result is called RNA. This long, thin molecule has many roles, including transmitting information, regulating the cell’s activities and helping molecular machines perform various tasks. But when its job is done, an RNA molecule must be broken apart. The job of destroying RNA is crucial for without it the cell’s RNA would rapidly build up and kill the cell. So cells are equipped with an intricate machine that chops up RNA molecules when they no longer are needed. This RNA degradation machine is called the exosome and it is comprised of ten finely-tuned proteins, nine of which form a cylinder through which the spent RNA is threaded. The tenth protein then chops up the RNA molecule. New research is now elucidating just how the exosome works, and the results pose yet more profound problems for evolution.” Read more: