R. Leonardo Petrucelli received his doctoral degree from Loyola University Chicago in 2000, working with Benjamin Wolozin, MD, PhD, to study the structure and function of alpha-synuclein, a gene product involved in the pathogenesis of Parkinson's disease. Dr. Petrucelli next pursued his research interests at the Mayo Clinic in Jacksonville, Florida to work in the laboratories of John Hardy PhD and Mike Hutton PhD. At the Mayo Clinic, his projects have focused on identifying substrates of parkin, a protein thought to be directly involved in the development of Parkinson's, and understanding the molecular mechanisms responsible for selective dopaminergic cell death in Parkinson's disease. Dr. Petrucelli and colleagues recently identified tau as parkin substrate, and discovered that tau protein accumulates in autosomal recessive juvenile parkinsonism (ARJP). Moreover, ARJP brain tissue shows markers of tau pathology and NFT formation. He also demonstrated that parkin protects against the toxicity associated with over expression of mutant alpha-synuclein and that the over expression of this protein selectively affects domainergic neurons and impairs net proteasome activity. He has extended these findings to develop in vivo mouse model of proteasomal activity that can directly correlate proteasome activity to abnormal protein accumulation, a hallmark of many neurodegenerative diseases including Parkinson's disease. Dr. Petrucelli is currently an assistant professor at Mayo Clinic Jacksonville.