Prosapip1-Dependent Synaptic Adaptations in the Nucleus Accumbens Drive Alcohol Intake, Seeking, and Reward

The mammalian target of rapamycin complex 1 (mTORC1), a transducer of local dendritic translation, participates in learning and memory processes as well as in mechanisms underlying alcohol-drinking behaviors. Using an unbiased RNA-seq approach, we identified Prosapip1 as a novel downstream target of mTORC1 whose translation and consequent synaptic protein expression are increased in the nucleus accumbens (NAc) of mice excessively consuming alcohol. We demonstrate that alcohol-dependent increases in Prosapip1 levels promote the formation of actin filaments, leading to changes in dendritic spine morphology of NAc medium spiny neurons (MSNs). We further demonstrate that Prosapip1 is required for alcohol-dependent synaptic localization of GluA2 lacking AMPA receptors in NAc shell MSNs. Finally, we present data implicating Prosapip1 in mechanisms underlying alcohol self-administration and reward. Together, these data suggest that Prosapip1 in the NAc is a molecular transducer of structural and synaptic alterations that drive and/or maintain excessive alcohol use. •Alcohol intake initiates mTORC1-dependent translation of Prosapip1 in the NAc•Prosapip1 contributes to alcohol-dependent actin dynamics and spine morphology•Alcohol-dependent synaptic localization of GluA2-lacking AMPAR requires Prosapip1•Prosapip1-dependent cellular adaptations drive alcohol seeking, drinking, and reward Laguesse et al. identified Prosapip1 as a novel downstream target of mTORC1 in the nucleus accumbens that promotes actin reorganization as well as morphological and synaptic alterations that in turn drive alcohol drinking and seeking behaviors.