Fig. 4.

Multiple open components. Example histograms and single-channel current traces for different loop B mutants. Arrow indicates the long-opening component. There was no agonist present (spontaneous currents). In all constructs, the background was αDYS (Supplemental Data). Long openings are apparent in the background (no binding site mutations) and with the binding site mutations αG153S, (αG153S+αY93F), and (αG153S+αY190F). They were absent with the mutations (αG153S+ αG147S) and (αG153S+αY198F). The long openings possibly arise from a local isomerization of αTrp149 (Purohit and Auerbach, 2010).