Required, with oct-8, for the localization of a subset of 7 transmembrane domain odorant receptors, including odr-10, to the cilia of olfactory neurons AWA and AWC (PubMed:9590179, PubMed:24603482). Regulates chemotaxis responses to benzaldehyde, diacetyl and 2,4,5-trimethylthiazole in AWA and AWC neurons (PubMed:8348618). Plays a role in nociceptive neurons to mediate avoidance of high oxygen (PubMed:16581509). Interacts with odr-8 and odr-10. Punctate expression in dendrite and axons. Expressed in the amphid head neurons AWA, AWC, AWB, ADF, ADL, ASG, ASH, ASI, ASJ, and ASK, and in the phasmid tail neurons, PHA and PHB. Expression is seen from 3-fold embryonic stage onward. Failure to localize the diacetyl receptor odr-10. Belongs to the ODR-4 family.