RNA Structure Comes of Age

its receptor, could not have been predicted. The first * Department of Chemistry and Biochemistry talk by J. Doudna (Yale University) provided new insights University of Colorado into the structure and introduced what were to become Boulder, Colorado 80309 the leitmotifs of the meeting: domains, specific ion bind-Motifs, and Recognition. .. , " summed up these topics in the context of the largest ribosomal RNA domain structure solved thus far and pointed out the importance The first ever meeting devoted entirely to RNA Structure of metals, water-mediated hydrogen bonds, the 2ЈOH, was held under the redwoods on the University of Cali-and stacking interactions in holding RNA together. Steitz fornia, Santa Cruz campus, June 26–29, 1997. Meeting also reminded us that the non-Watson-Crick base pairs organizers H. incorporated into even the double helical regions of RNA Jr., and C. Wilson should be congratulated on having not only affect the groove widths but also provide a the prescience to organize this event. Even 2 1/2 years varied pattern of proton donors and acceptors in the ago, with the publication of the first large RNA structure major and minor grooves for recognition by proteins. since tRNA in 1978, the 48-nucleotide hammerhead ribo-zyme (Pley et al., 1994), it would have been hard to Structures of Small RNA Motifs predict the sheer numbers of recent successes in the One of the most striking aspects of the meeting was the past year or so (Figure 1). The sense of excitement at tremendous progress made in determining structures of the meeting was not unlike the feeling engendered in the small modular units of RNA structure: short helices, scientists by the overwhelming amounts of new data mismatches, bulges, internal loops, pseudoknots, etc. sent back by the recent explorations of the Sojourner No fewer than 30 such structures were presented using on Mars. After so many years with only a few RNA struc-both NMR and X-ray crystallography (Table 1). For many tures to analyze, we were now presented with more systems, the structural biologists use a reductionist ap-structural data than could be fully appreciated during proach where a small module or folding domain is stud-the short span of the meeting. It was also clear that ied. Even the crystal structures of RNA discussed above scientists are already looking beyond the pure beauty are still only modules of larger RNAs. However, studies of these new structures to what they can …