Structural biology. The ribosome is a ribozyme.
Ribosomes, the cellular factories that manufacture proteins, contain both RNA and protein, but exactly how all of the different ribosomal components contribute toprotein synthesis is still not clear. Now, as Thomas Cech explains in his Perspective, atomic resolution of the structure of the large ribosomal subunit reveals that, as predicted by those convinced of a prebiotic RNA world, RNA is the catalytic component with proteins being the structural units that support and stabilize it (Ban et al., Nissen et al., Muth et al.).