Updated project metadata. LRRK2 mutations are associated with both familial and sporadic forms of Parkinson’s disease (PD). Convergent evidence suggests that LRRK2 plays critical roles in regulating striatal function. Here, by using knock-in mouse lines that express the two most common LRRK2 pathogenic mutations—G2019S and R1441C—we investigated how pathogenic LRRK2 mutations altered striatal physiology. To identify the signaling pathways that underlie the motor learning deficits, specifically in the RC mice we performed six-plex tandem mass tag (TMT) quantitative mass spectrometry (MS) to compare the protein expression of either RC or GS and WT mice following the five days of the rotarod test.