title: Lrrk2 interaction with alpha-synuclein in diffuse Lewy body disease.
abstract: Mutations of the leucine-rich repeat kinase 2 (LRRK2) gene are the leading cause of genetically inherited Parkinson's disease (PD) and its more severe variant diffuse Lewy body disease (DLB). Pathological mutations in Lrrk2 are autosomal dominant, suggesting a gain of function. Mutations in alpha-synuclein also produce autosomal dominant disease. Here we report an interaction between Lrrk2 and alpha-synuclein in a series of diffuse Lewy body (DLB) cases and in an oxidative stress cell based assay. All five cases of DLB, but none of five controls, showed co-immunoprecipitation of Lrrk2 and alpha-synuclein in soluble brain extracts. Colocalization was also found in pathological deposits in DLB postmortem brains by double immunostaining. In HEK cells transfected simultaneously with plasmids expressing Lrrk2 and alpha-synuclein, co-immunoprecipitation of Lrrk2 and alpha-synuclein was detected when they were exposed to oxidative stress by H(2)O(2). Taken together, these results suggest the possibility that in PD and related synucleinopathies, oxidative stress upregulates alpha-syn and Lrrk2 expression, paving the way for pathological interactions. New therapeutic approaches to PD and the synucleinopathies may result from limiting the interaction between Lrrk2 and alpha-synuclein.
authors.affiliation: Kinsmen Laboratory of Neurological Research, University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z3.
authors.forename: Hong
authors.initials: H
authors.lastname: Qing
authors.forename: Yanyan
authors.initials: Y
authors.lastname: Zhang
authors.forename: Yulin
authors.initials: Y
authors.lastname: Deng
authors.forename: E G
authors.initials: EG
authors.lastname: McGeer
authors.forename: P L
authors.initials: PL
authors.lastname: McGeer
mesh_terms: D001921:Brain / Q000378:metabolism / Q000473:pathology; D002460:Cell Line; D006801:Humans; D047468:Immunoprecipitation; D000071158:Leucine-Rich Repeat Serine-Threonine Protein Kinase-2; D020961:Lewy Body Disease / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D018384:Oxidative Stress; D017346:Protein Serine-Threonine Kinases / Q000235:genetics / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism; D051844:alpha-Synuclein / Q000235:genetics / Q000378:metabolism*
chemical_list: D012333:RNA, Messenger; D051844:alpha-Synuclein; C495280:LRRK2 protein, human; D000071158:Leucine-Rich Repeat Serine-Threonine Protein Kinase-2; D017346:Protein Serine-Threonine Kinases