NG2 (Cspg4): Cell Surface Proteoglycan on Oligodendrocyte Progenitor Cells in the Developing and Mature Nervous System

NG2 is an integral membrane chondroitin sulfate proteoglycan with a large extracellular domain and a short cytoplasmic tail. In the nervous system, NG2 is expressed on oligodendrocyte precursor cells (NG2 cells), Schwann cells, and pericytes. NG2 expression is associated with proliferative or activated phenotypes. Through its interaction with growth factors and their receptors, integrins, and extracellular matrix proteins such as collagen VI, NG2 regulates a variety of cellular phenomena including cell adhesion and spreading, migration, and proliferation. The phenotypes of total and conditional NG2-knockout mice indicate a critical role for NG2 in fine-tuning the cellular proliferative response and in mediating cell-cell or cell-matrix interactions.