Figure 1. Fluorescent image and conceptual structure of PNNs.
(A) A neuron expressing parvalbumin (red) covered by a PNN as visualized by WFA fluorescent staining. Scale bar, 3 μm. (B) Structural components and regulators of PNN structure: hyaluronan, tenascin-R, hyaluronan and proteoglycan link proteins (HAPLN1, HAPLN4), the lecticans (aggrecan, brevican, neurocan, and versican), and enzymes that degrade the extracellular matrix (MMP and ADAMTS proteins).