SEX-SPECIFIC TRAJECTORIES OF REELIN-DEPENDENT MATURATION OF DEEP LAYER PREFRONTAL NEURONS

ABSTRACT Throughout early adulthood, the anatomical and functional maturation of PFC circuitry continues under the influence of multiple extrinsic and intrinsic factors, most notably electrical activity, and molecular cues. We previously showed that the extracellular matrix protein reelin orchestrates the structural and functional maturation of deep layers medial PFC (mPFC) pyramidal neurons. Additionally, we reported that reelin haploinsufficiency is associated to prefrontal disruptions of long-term memory retention thereby illustrating the eminent role of reelin in cognitive maturation of the PFC. Prefrontal maturation follows a sex-specific developmental pattern, supporting the existence of sexual differences in the morphology-functional properties PFC. Here, we interrogated the role of reelin in the functional maturation of excitatory networks in the mPFC. The developmental trajectory of reelin’s expression and deep layer pyramidal neurons synaptic plasticity was tracked in the mPFC of male and female mice, from the juvenile period to adulthood. To assess the role of reelin in both sexes, wild-type and heterozygous reeler mice (HRM) were compared. The results show that the maturational profile of reelin expression in the mPFC is sex-dependent and that the developmental trajectory of long-term potentiation is different between wild-type males and females. These data demonstrate reelin’s influence on prefrontal synapses is sex and period specific