['To obtain an insight into the function of cellular prion protein (PrPC), we studied PrPC-interacting proteins (PrPIPs) by analysing a protein microarray.', 'We identified 47 novel PrPIPs by probing an array of 5000 human proteins with recombinant human PrPC spanning amino acid residues 23-231 named PR209.', 'The great majority of 47 PrPIPs were annotated as proteins involved in the recognition of nucleic acids. Coimmunoprecipitation and cell imaging in a transient expression system validated the interaction of PR209 with neuronal PrPIPs, such as FAM64A, HOXA1, PLK3 and MPG. However, the interaction did not generate proteinase K-resistant proteins. KeyMolnet, a bioinformatics tool for analysing molecular interaction on the curated knowledge database, revealed that the complex molecular network of PrPC and PrPIPs has a significant relationship with AKT, JNK and MAPK signalling pathways.'] Does protein microarray analysis identify human cellular prion protein interactors?