General Information

Mice: FVB

Expression of the full-length human wild type LRRK2 protein using the bacterial artificial chromosome (BAC).

Endogenous LRRK2: yes

Corresponding human genotype: LRRK2 is the greatest known genetic contributor to Parkinson’s disease.

Targeted gene: LRRK2

References: Li 2009, Merlose 2010, Winner 2011

Transgene expression

Overall transgene expression is about 3.5 fold higher than the endogenous LRRK2 in the brain of the transgenic animals (although it is much higher in the hippocampus: 20 fold). Anatomical expression patterns are similar to the endogenous mouse gene but the level of the protein is increased.

Neurodegeneration

22-24 months: No differences are detected in the number of TH-positive cells in the SN.

Dopamine Homeostasis

18 months: In vivo striatal levels of DA are significantly lower in transgenic animals compared to control littermates at baseline (striatal microdialysis). No differences are observed after amphetamine injection Note that no differences in the level of DA or its metabolites (DOPAC, HVA) are observed in the striatum of the transgenic mice post-mortem (HPLC). A modest increase in the number of striatal dopamine D1 (significant) and D2 (non-significant) receptors density is observed.

Inclusions

up to 24 months: No abnormalities can be seen with alpha-synuclein, phosphorylated alpha-synuclein or phosphorylated tau staining.

Motor Behaviours

22-24 months: No significant changes are observed during motor assessments (open field, beam crossing test, inked footprint analysis, negative geotaxis test).

Response to dopaminergic treatment

18 months: No differences are observed the DA/metabolites striatal ratio changes and stored DA induced by treatment with the D2 receptor antagonist raclopride.

Non-motor Behaviours

Not reported

Electrophysiology

Not reported

Neuroinflammation

18-24 months: No visible changes are observed in activated microglia (Iba-1 immunostaining).