Scientists at The Rockefeller University have created the most detailed three-dimensional images to date of an important step in the process by which cells make the nano-machines responsible for producing all-important protein. The results, described December 15 in Science, are prompting the researchers to re-evaluate how they envision this early phase in the construction of ribosomes.
“The structure they determined, shown above, belongs to a particle formally called the “small subunit processome.” Before this particle can fulfill its destiny to become the smaller half of a complete ribosome, the RNA within it needs to be folded, tweaked, and cut.
“Initially, we thought of the small subunit processome as a product on an assembly line, with molecular workers arriving from outside, much like the robots that would put together a car. But that analogy no longer appears apt,” says senior author Sebastian Klinge, head of the Laboratory of Protein and Nucleic Acid Chemistry.