Loss of LrrK2 Function Potentiates Dopamine Signaling in the Striatum to Promote Compulsive Alcohol Use

Abstract

Long-lasting plastic changes in the striatum play a central role in driving the transition from hedonic to compulsive alcohol drinking, a hallmark of alcohol use disorders. It is known that the propensity to undergo this transition varies with the individual, yet the underlying molecular mechanisms are not well understood. Here, we report that the Parkinson’s-related protein Leucine-rich repeat kinase 2 (LRRK2) plays a role in in this transition to compulsive alcohol drinking by modulating the function of dopamine D1 receptors within the striatonigral pathway. We find that alcohol decreases LRRK2 kinase activity in the dorsal striatum and that deletion of the Lrrk2 gene specifically from D1-expressing striatal neurons promotes compulsive-like alcohol drinking in mice by strengthening D1 receptor signaling and function. These findings identify a novel role for Lrrk2 in the striatum and suggest that Lrrk2 function promotes resilience for compulsive alcohol drinking and the development of alcohol use disorders.