HIF2α: the interface between oxygen-sensing systems in physiology and pathology

More than 100 years after the original descriptions of altitude adaptation, it is now clear that many of these responses are mediated by a specific isoform of the transcription factor hypoxia-inducible factor (HIF-2α). Here, we review this work, including connectivity with the oxygen chemosensitive response itself, and with paraganglioma, a tumour often affecting chemosensitive tissues.