Has been proposed to act as a receptor for neuronostatin, a peptide derived from the somatostatin/SST precursor (PubMed:22933024). Involved in blood sugar regulation through the induction of glucagon in response to low glucose (By similarity). (Microbial infection) Required for intoxication by Pseudomonas aeruginosa exotoxin A and Campylobacter jejuni CDT. May contribute to the retrograde transport of bacterial toxins, including cholera toxin, from the trans-Golgi network to the endoplasmic reticulum. Cleaved by FURIN to yield two fragments of 17 and 35 kDa that remain associated via a disulfide bond. Belongs to the LU7TM family.