Annexin V: the key to understanding ion selectivity and voltage regulation?

Annexin V is a Ca(2+)-dependent membrane-binding protein that forms voltage-dependent Ca2+ channels in phospholipid bilayers and is the first ion channel to be structurally and functionally characterized. Data outlined here indicate that key amino acid residues act as selectivity filters and voltage sensors, thereby regulating the permeability of the channel pore to ions.