Cellular oxygen sensor which regulates the stability and the activity of hypoxia-inducible transcription factor, hif-1. In normoxic conditions, hydroxylates hif-1 targeting it for vhl-1-mediated proteasomal degradation (PubMed:11595184). In addition, regulates hif-1 transcriptional activity in a vhl-1-independent manner and independently of its hydroxylase activity (PubMed:19737748). By regulating hif-1 activity, controls several cellular responses. Mediates susceptibility to B.thuringiensis and V.cholerae pore-forming toxins and enteropathogenic E.coli (PubMed:20011506, PubMed:16091039). Mediates susceptibility to P.aeruginosa PAO1-mediated killing by regulating resistance to cyanide produced by P.aeruginosa (PubMed:10611362, PubMed:11591663, PubMed:20865124). Mediates resistance to S.aureus-mediated killing (PubMed:22792069). In addition, plays a role in heat acclimation, neuronal development, behavioral responses to reoxygenation and hydrogen sulfide, iron homeostasis and aging (PubMed:12686697, PubMed:18477695, PubMed:22405203, PubMed:19372390, PubMed:22396654). In neurons, involved in mitochondrion fusion during reoxygenation (PubMed:24385935). Involved in egg laying (PubMed:10611362, PubMed:11813735). Regulates the trafficking of the glutamate receptor glr-1, probably independently of hif-1, by regulating lin-10 subcellular localization in response to oxygen levels. May hydroxylate lin-10. 2-oxoglutarate + L-prolyl-[hypoxia-inducible factor alpha subunit] + O2 = CO2 + succinate + trans-4-hydroxy-L-prolyl-[hypoxia-inducible factor alpha subunit] Binds 1 Fe(2+) ion per subunit. Inhibited by Co(2+) and dimethyloxalylglycine (PubMed:11595184). Inhibited by the iron chelator 2, 2'-dipyridyl (PubMed:19737748). Interacts (via catalytic domain) with lin-10 (via N-terminus); the interaction regulates lin-10 subcellular localization; the interaction is direct (PubMed:22252129). Interacts (via catalytic domain) with swan-1 (via WD 1-3 repeats); the interaction may regulate vhl-1-independent hif-1 transcriptional activity; the interaction is direct (PubMed:20865124). Interacts (via C-terminus) with cysl-1; the interaction is enhanced by hydrogen disulfide and activates hif-1-mediated transcription; the interaction is direct (PubMed:22405203). In interneurons, localizes throughout the ventral cord dendrites. In interneurons, localizes throughout the ventral cord dendrites. In interneurons, localizes in puncta (which probably correspond to endosomes) along the ventral cord. Localization to puncta is regulated by oxygen levels. Co-localizes with lin-10 in puncta. In larvae and adults, expressed in pharyngeal and body wall muscles. Induced by hypoxia. The MYND-type domain is not required for oxygen-mediated hif-1 degradation or for inhibiting hif-1 transcriptional activity (PubMed:19737748). Susceptibility to S.aureus infection requires the Ser-rich region but not the MYND-type or Fe2OG dioxygenase domains (PubMed:22792069). RNAi-mediated knockdown causes enhanced resistance to polyglutamine or amyloid-beta-mediated paralysis and an increase in adult life span (PubMed:19372390). In addition, causes resistance to B.thuringiensis pore-forming toxin CryA21-mediated toxicity (PubMed:20011506).