Computer models plus observations of RNA inside a cell help
scientists home in on a short list of interesting RNA ‘machines.’
DNA stores the information of life, proteins provide the
action, and in between sits elusive RNA, which serves both as a database of
information and as a molecular machine. RNA is more flexible than DNA, and its
three-dimensional structures are more complex than proteins. When studied in
the laboratory, RNA bends into so many convolutions that it is nearly
impossible to tease out which folds are worthy of scientific inquiry and which
can safely be ignored.