The identification and characterization of proteins and peptides involved in causing or preventing many important diseases is the central focus of many NIH-funded research programs at the New York University School of Medicine. Recent developments in mass spectrometry have made it possible to gain essential information about these proteins that would be impractical or impossible to obtain in any other way. The NYU Protein Analysis Facility within the Skirball Institute of Biomolecular Medicine at-the NYU School of Medicine is strongly committed to assuring that scientists here can benefit from this new technology. Because of its versatility, high sensitivity, ease of use and high speed of sample processing, Matrix-Assisted Laser Desorption Time-of-Flight (MALDI- TOF) mass spectrometry is essential for many of our protein analyses. Examples of NIH-funded research projects that will benefit from the requested MALDI-TOF mass spectrometer include the identification of signal transduction proteins involved in nerve cell development, structural characterization of HIV-1 antigens for AIDS vaccine development, identification of signaling proteins involved in intracellular stress responses, structural studies of proteins involved in insulin signal transduction, the study of exotoxin production and virulence responses in pathogenic Staphylococcus aureus, molecular mechanisms that modulate opioid receptor function, the characterization of amyloid peptides involved in Alzheimer's Disease, the pathogenic role of apoptosis in Shigella infection, the pathology of Alzheimer's Disease and aging, signaling proteins involved in neuromuscular synapse formation, and the study of proteins that are important for transcriptional regulation in hepatitis B.