Finding the gates

Abstract

Structural Biology Hundreds of ion channel structures are available thanks in large part to recent advances in electron microscopy. Insights into channel gating have come from structures of the same channel in different conformational states, supported by biophysical approaches. Gating can occur in hydrophobic regions of the pore even when the diameter is larger than that of a water molecule. Rao et al. simulate the water distribution in nearly 200 representative ion channel structures. Using a machine learning approach, they classify the hydrophobicity–pore radius landscape into two regions, depending on whether water is likely to be excluded or not. This enables them to predict the presence of hydrophobic gates by analysis of the hydrophobicity and pore radius of a single set of coordinates without molecular dynamic simulation of the structure. Proc. Natl. Acad. Sci. U.S.A. 116 , 13989 (2019).