Characterization of a specific interaction between ADAM23 and cellular prion protein

ADAMs are transmembrane proteins implicated in several biological functions, including cytokine and growth factor shedding, fertilization, muscle and nervous system development. Here, we show for the first time that ADAM23, which is predominantly expressed in the central nervous system, co-localizes with cellular prion protein (PrPC) at plasma membrane of mouse hippocampal neurons and neuroblastoma cells. Co-immunoprecipitation and pull-down assay showed a physical interaction between ADAM23 and both recombinant and endogenous PrPC. Glycosylation seems to be not relevant to the observed interaction since both ADAM23 and PrPC recombinant proteins expressed in bacteria or extracted from eukaryotic cells treated with tunicamycin are still able to bind each other. In vitro binding assays also suggested that the disintegrin domain of ADAM23 is able to interact directly with PrPC. Taken together, these findings point out PrPC as a novel molecular partner for ADAM23 in the nervous systems.