Characterization of Densin-180, a New Brain-Specific Synaptic Protein of the O-Sialoglycoprotein Family

摘要: We purified an abundant protein of apparent molecular mass 180 kDa from the postsynaptic density fraction rat forebrain and obtained amino acid sequences three tryptic peptides generated protein. The were used to design a strategy for cloning cDNA encoding by polymerase chain reaction. open reading frame encodes novel predicted 167 kDa. have named densin-180. Antibodies raised against carboxyl densin-180 recognize band on immunoblots that is enriched in fraction. Immunocytochemical localization dissociated hippocampal neuronal cultures shows highly concentrated at synapses along dendrites. message brain specific more than cerebellum. sequence contains 17 leucine-rich repeats, sialomucin domain, transmembrane PDZ domain. This arrangement domains similar several adhesion molecules, particular GPIbalpha, which mediates binding platelets von Willebrand factor. propose participates between presynaptic membranes glutamatergic synapses.