title: Differential LRRK2 expression in the cortex, striatum, and substantia nigra in transgenic and nontransgenic rodents.
abstract: Mutations in leucine-rich repeat kinase 2 (LRRK2) are found in a significant proportion of late-onset Parkinson's disease (PD) patients. Elucidating the neuroanatomical localization of LRRK2 will further define LRRK2 function and the molecular basis of PD. Here, we utilize recently characterized monoclonal antibodies to evaluate LRRK2 expression in rodent brain regions relevant to PD. In both mice and rats, LRRK2 is highly expressed in the cortex and striatum, particularly in pyramidal neurons of layer V and in medium spiny neurons within striosomes. Overall, rats have a more restricted distribution of LRRK2 compared with mice. Mice, but not rats, show high levels of LRRK2 expression in the substantia nigra pars compacta. Expression of the pathogenic LRRK2-G2019S protein from mouse bacterial artificial chromosome (BAC) constructs closely mimics endogenous LRRK2 distribution in the mouse brain. However, LRRK2-G2019S expression derived from human BAC constructs causes LRRK2 to be expressed in additional neuron subtypes in the rat such as striatal cholinergic interneurons and the substantia nigra pars compacta. The distribution of LRRK2 from human BAC constructs more closely resembles descriptions of LRRK2 in humans and nonhuman primates. Computational analyses of DNA regulatory elements in LRRK2 show a primate-specific promoter sequence that does not exist in lower mammalian species. These noncoding regions may be involved in directing neuronal expression patterns. Together, these studies will aid in understanding the normal function of LRRK2 in the brain and will assist in model selection for future studies.
authors.affiliation: Center for Neurodegeneration and Experimental Therapeutics, Department of Neurology, University of Alabama at Birmingham, Birmingham, Alabama, 35294.
authors.forename: Andrew B
authors.initials: AB
authors.lastname: West
authors.forename: Rita M
authors.initials: RM
authors.lastname: Cowell
authors.forename: João P L
authors.initials: JP
authors.lastname: Daher
authors.forename: Mark S
authors.initials: MS
authors.lastname: Moehle
authors.forename: Kelly M
authors.initials: KM
authors.lastname: Hinkle
authors.forename: Heather L
authors.initials: HL
authors.lastname: Melrose
authors.forename: David G
authors.initials: DG
authors.lastname: Standaert
authors.forename: Laura A
authors.initials: LA
authors.lastname: Volpicelli-Daley
mesh_terms: D000818:Animals; D002540:Cerebral Cortex / Q000502:physiology*; D022202:Chromosomes, Artificial, Bacterial / Q000235:genetics; D003342:Corpus Striatum / Q000502:physiology*; D055786:Gene Knockout Techniques; D007395:Interneurons / Q000502:physiology; D000071158:Leucine-Rich Repeat Serine-Threonine Protein Kinase-2; D008297:Male; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D009154:Mutation; D011401:Promoter Regions, Genetic; D017346:Protein Serine-Threonine Kinases / Q000235:genetics / Q000378:metabolism*; D017966:Pyramidal Cells / Q000502:physiology; D020318:Rats, Long-Evans; D017207:Rats, Sprague-Dawley; D055647:Rats, Transgenic; D016415:Sequence Alignment; D013045:Species Specificity; D013378:Substantia Nigra / Q000502:physiology*
chemical_list: C495280:LRRK2 protein, human; C547428:LRRK2 protein, rat; D000071158:Leucine-Rich Repeat Serine-Threonine Protein Kinase-2; C495279:Lrrk2 protein, mouse; D017346:Protein Serine-Threonine Kinases
keywords: Parkinson's disease; bacterial-artificial chromosome (BAC) transgenics; neurodegeneration; nigrostriatal circuit