Genetic basis of oxygen sensing in the carotid body: HIF2α and an isoform switch in cytochrome c oxidase subunit 4.
Bishop T., Ratcliffe PJ.
The mechanistic basis of the marked oxygen sensitivity of glomus cells in the carotid body has long puzzled physiologists. In this issue of Science Signaling, Moreno-Domínguez et al. show the critical importance of high levels of hypoxia-inducible factor, HIF2α/EPAS1, and the nuclear-encoded mitochondrial cytochrome c oxidase subunit, COX4I2, in glomus cell sensitivity to hypoxia.