This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. This collaborative project involves the proteomic characterization of signaling complexes in neuronal cell axoplasm. Two types of complexes are under investigation, those important for long distance communication along the axon, and those involved in localized responses. Both affinity and differential proteomics incorporating advanced mass spectrometry methods are being employed. In addition, mass spectrometric methods are being developed to identify and establish novel posttranslational modifications in neuronal axoplasm proteins.