NG2

NG2, also known as nerve/glial antigen 2 or CSPG4, is a transmembrane chondroitin sulfate proteoglycan encoded by the CSPG4 gene. It is widely studied for its roles in neural development and vascular biology.

NG2 is prominently expressed by oligodendrocyte precursor cells (OPCs) in the central nervous system and by pericytes in the vasculature, with broader expression in various progenitor cell populations. It functions as a cell surface receptor that participates in cell adhesion, migration, and proliferation. The extracellular portion of NG2 carries chondroitin sulfate glycosaminoglycan chains and can act as a co-receptor in signaling pathways, modulating growth factor signals such as those from PDGF and FGF. NG2 also interacts with extracellular matrix components like collagen and laminin and with integrins, influencing process extension and cell motility.

In development, NG2-expressing progenitors guide OPC migration and timing of myelination. Following CNS injury, NG2 expression is often upregulated and NG2-positive cells contribute to remyelination processes. In the vasculature, NG2 on pericytes supports vessel maturation and angiogenesis; proteolytic shedding of the NG2 ectodomain can release soluble fragments that affect surrounding cells.

Clinical and research relevance includes NG2 being a marker for certain glial progenitors and pericytes, as well as a potential therapeutic target in gliomas and other cancers where CSPG4/NG2 is expressed. Its multifaceted roles across neural development, vascular biology, and disease make NG2 a focus of ongoing investigation.