REGIONAL EXPRESSION AND CHROMOSOMAL LOCALIZATION OF THE DELTA-OPIATE RECEPTOR GENE

The delta opiate receptor gene has been cloned from the mouse neurobla stoma-rat glioma hybrid cell NG108-15. The clone that we isolated is a pparently identical to that reported by Evans et al. [Evans, C. J., Ke ith, D. E., Jr., Morrison, H., Magendzo, K. & Edwards, R. H. (1992) Sc ience 258, 1952-1955] and essentially identical with that of Kieffer e t al. [Kieffer, B. L., Befort, K., Gaveriaux-Ruff, C. & Hirth, C. G. ( 1992) Proc. Natl. Acad. Sci. USA 89, 12048-12052]. We have found full- length transcripts of the gene in mouse brain but in no other tissues examined. Within the brain the gene is expressed at low levels in many regions but transcripts are found in particularly large amounts in th e anterior pituitary and pineal glands. Since these tissues are locate d outside the blood-brain barrier, opioid peptides easily can reach re ceptors in these areas from the blood. The gene, which is present as a single copy, has been mapped to the distal region of mouse Chromosome 4.