Figure 1. Heterogeneity of Slo2.2 particles in 20 – 160 mM NaCl.

(A) Ten 3D class averages of Slo2.2 vitrified in the presence of 20 mM, 40 mM, 80 mM and 160 mM Na⁺. The nine classes that closely resemble closed, Na⁺-free Slo2.2 are colored red and the open class is colored blue. (B) Fraction of particles in each class is shown for the four Na⁺ concentrations. The sum of fractions of all ten classes for each Na⁺ concentration is 1.0.