TRPA1 underlies a sensing mechanism for O(2).

The redox-sensitive TRP channel TRPA1 is activated in hyperoxic and hypoxic conditions directly through modification of cysteine residues by O2 and indirectly through prolyl hydroxylation by PHDs, enzymes related to the hypoxia-inducible factor HIF-1, thus helping to explain how O2 is sensed by sensory and vagal neurons.