Paper Chase is a research database designed to offer abstracts of research articles published in journals that have a highly rated impact factor as determined by ISI Impact Factor and PageRank. Abstracts are organized by date, with the most recently published papers listed first. 

Paper Chase

Dopamine covalently modifies and functionally inactivates parkin.

Nat. Med.. 10 16, 2005;11(11):1214-21.
LaVoie MJ, Ostaszewski BL, Weihofen A, Schlossmacher MG, Selkoe DJ.

Center for Neurologic Diseases, Department of Neurology, Brigham and Women's Hospital, 77 Avenue Louis Pasteur, HIM 7th Floor, Boston, Massachusetts 02115, USA. mlavoie@rics.bwh.harvard.edu

Abstract:

Inherited mutations in PARK2, the gene encoding parkin, cause selective degeneration of catecholaminergic neurons in the substantia nigra and locus coeruleus of the brainstem, resulting in early-onset parkinsonism. But the role of parkin in common, sporadic forms of Parkinson disease remains unclear. Here we report that the neurotransmitter dopamine covalently modifies parkin in living dopaminergic cells, a process that increases parkin insolubility and inactivates its E3 ubiquitin ligase function. In the brains of individuals with sporadic Parkinson disease, we observed decreases in parkin solubility consistent with its functional inactivation. Using a new biochemical method, we detected catechol-modified parkin in the substantia nigra but not other regions of normal human brain. These findings show a vulnerability of parkin to modification by dopamine, the principal transmitter lost in Parkinson disease, suggesting a mechanism for the progressive loss of parkin function in dopaminergic neurons during aging and sporadic Parkinson disease.