Persistent Increases of PKM? in Sensorimotor Cortex Maintain Procedural Long-Term Memory Storage.

ABSTRACT: Procedural motor learning and memory are accompanied by changes in synaptic plasticity, neural dynamics, and synaptogenesis. Missing is information on the spatiotemporal dynamics of the molecular machinery maintaining these changes. Here we examine whether persistent increases in PKM?, an atypical protein kinase C (PKC) isoform, store long-term memory for a reaching task in rat sensorimotor cortex that could reveal the sites of procedural memory storage. Specifically, perturbing PKM? synthesis (via antisense oligodeoxynucleotides) and blocking atypical PKC activity (via zeta inhibitory peptide [ZIP]) in S1/M1 disrupts and erases long-term motor memory maintenance, indicating atypical PKCs and specifically PKM? store consolidated long-term procedural memories. Immunostaining reveals that PKM? increases in S1/M1 layers II/III and V as performance improved to an asymptote. After storage for 1 month without reinforcement, the increase in M1 layer V persists without decrement. Thus, the persistent increases in PKM? that store long-term procedural memory are localized to the descending output layer of the primary motor cortex.

SUBMITTER: Gao PP 

PROVIDER: S-EPMC6123865 | biostudies-literature | 2018 Jul

REPOSITORIES: biostudies-literature