Astrocytic Regulation of aberrant perineuronal net formation in Mecp2-null Neocortex

PNNs are lattice-like substructures of extracellular matrix (ECM) that enwrap specific subpopulations of neurons. PNNs are essential in the modulation of neuronal plasticity and brain maturation, and their enzymatic disruption can partially restore plasticity in adults and improve memory.

Although precocious PNN formation is well-established in RTT, there is little known of the cellular, molecular, or biochemical underpinnings of their precocious formation. Further, whether precocious PNN formation is due to cell-autonomous or non-cell-autonomous mechanisms is not fully understood. While PNNs form on subsets of neurons throughout the brain, astrocytes secrete many ECM components that form PNNs, and they play a central role in controlling closure of the critical period.