Molecular mimicry in channel-protein structure.

The approach to probing the sequence-structure relationship of ion-channel proteins using small peptides stems from the abundance of sequence information and the virtual absence of structures at atomic resolution. It is anticipated that model peptides may fold predictably into stable structures and reproduce functional properties of specific proteins. Model peptides are well suited to the application of NMR methods to determine protein structure in a membrane environment or to high-resolution X-ray diffraction analysis. It is timely to ask what we have learned through this strategy and where it may lead in our quest to understand the sequence-structure determinism.