Protein folds in channel structure.

Advances have been made during the past year in our understanding of the structural basis of channel-protein function. With the convergence of conceptual and technical breakthroughs, we stand at the threshold of an exciting phase in the analysis of membrane proteins with the same molecular detail that used to be the exclusive domain of aqueous soluble proteins. The provocative prospect of establishing the occurrence of minimum units of structure with specific functional attributes may provide a realistic pathway towards understanding the fundamental principles underlying the sequence-structure determinism.