From Sequences to Shapes and Back: A Case Study in RNA Secondary Structures

摘要: RNA folding is viewed here as a map assigning secondary structures to sequences. At fixed chain length the number of sequences far exceeds structures. Frequencies are highly non-uniform and follow generalized form Zipf's law: we find relatively few common many rare ones. By using an algorithm for inverse folding, show that sharing same structure distributed randomly over sequence space. All can be accessed from arbitrary by mutations much smaller than length. The space percolated extensive neutral networks connecting nearest neighbours into identical Implications evolutionary adaptation applied molecular evolution evident: finding particular mutation selection simpler expected and, even if catalytic activity should turn out sparse in structures, it hardly missed processes.