Protein microarray analysis identifies human cellular prion protein interactors.
OBJECTIVE
To obtain an insight into the function of cellular prion protein (PrPC), we studied PrPC-interacting proteins (PrPIPs) by analysing a protein microarray.


METHODS
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.


RESULTS
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.


CONCLUSIONS
Protein microarray is a useful tool for systematic screening and comprehensive profiling of the human PrPC interactome. Because the network of PrPC and interactors involves signalling pathways essential for regulation of cell survival, differentiation, proliferation and apoptosis, these observations suggest a logical hypothesis that dysregulation of the PrPC interactome might induce extensive neurodegeneration in prion diseases.
Satoh
J
J
Department of Bioinformatics and Molecular Neuropathology, Meiji Pharmaceutical University, Tokyo, Japan. satoj@my-pharm.ac.jp
Obayashi
S
S
Misawa
T
T
Sumiyoshi
K
K
Oosumi
K
K
Tabunoki
H
H
D015153:Blotting, Western; D002352:Carrier Proteins / Q000378:metabolism; D002460:Cell Line; D030541:Databases, Genetic; D019286:Endopeptidase K / Q000378:metabolism; D006801:Humans; D047468:Immunoprecipitation; D047908:Intracellular Signaling Peptides and Proteins; D048031:JNK Mitogen-Activated Protein Kinases / Q000378:metabolism; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism; D009474:Neurons / Q000378:metabolism; D009687:Nuclear Proteins; D018621:PrPC Proteins / Q000378:metabolism*; D040081:Protein Array Analysis; D017346:Protein Serine-Threonine Kinases / Q000378:metabolism; D051057:Proto-Oncogene Proteins c-akt / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D015203:Reproducibility of Results; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015398:Signal Transduction / Q000502:physiology; D025521:Tumor Suppressor Proteins; D000097868:Polo-like Kinases
D002352:Carrier Proteins; D019286:Endopeptidase K; D047908:Intracellular Signaling Peptides and Proteins; D048031:JNK Mitogen-Activated Protein Kinases; D020928:Mitogen-Activated Protein Kinases; D009687:Nuclear Proteins; D018621:PrPC Proteins; D017346:Protein Serine-Threonine Kinases; D051057:Proto-Oncogene Proteins c-akt; D012333:RNA, Messenger; D025521:Tumor Suppressor Proteins; C512398:PIMREG protein, human; C486256:PLK3 protein, human; D000097868:Polo-like Kinases