Proton conduction through gp91^phox

Previous Perspectives in the Journal of General Physiology have considered (a) the different advantages of two models of ion channel permeation and (b) whether ryanodine receptor adaptation might arise from flash photolysis. Each argument, over the choice of model or influence of technique, is an example of a classic scientific dispute. Here we turn to another hoary old problem—the identification of a “prime mover.”

The specific problem we are dealing with here concerns the structure and function of the voltage-gated proton channel in mammalian neutrophils. We have presented evidence recently that a component of the NADPH oxidase, gp91^phox, functions as a proton channel and as such plays an essential role in neutrophil action (Henderson and Meech, 1999). The proposal has proved controversial because the evidence we provided was necessarily circumstantial.