Molecular characterization of a new immunoglobulin superfamily protein with potential roles in opioid binding and cell contact. |
| |
Authors: | P R Schofield K C McFarland J S Hayflick J N Wilcox T M Cho S Roy N M Lee H H Loh P H Seeburg |
| |
Affiliation: | Genentech, Inc., Department of Developmental Biology, South San Francisco, CA 94080. |
| |
Abstract: | A purified opioid-binding protein has been characterized by cDNA cloning. The cDNA sequence predicts an extracellularly located glycoprotein of 345 amino acids. This protein does not possess a membrane-spanning domain but contains a C-terminal hydrophobic sequence characteristic of membrane attachment by a phosphatidylinositol linkage. It displays homology to the immunoglobulin protein superfamily, featuring three domains that resemble disulfide-bonded constant regions. More specifically, the protein is most homologous to a subfamily of proteins which includes the neural cell adhesion molecule (NCAM) and myelin-associated glycoprotein (MAG) and one subgroup of the tyrosine kinase growth factor receptors comprising the platelet-derived growth factor receptor (PDGF R), the colony-stimulating factor 1 receptor (CSF-1 R) and the c-kit protooncogene. These sequence homologies suggest that the protein could be involved in either cell recognition and adhesion, peptidergic ligand binding or both. |
| |
Keywords: | |
|
|