Capillary morphogenesis protein 2 (ANTXR2)

Capillary morphogenesis protein 2 (ANTXR2, CMG2) is a multifunctional cell-surface transmembrane receptor that plays critical roles in tissue physiology and disease. It is a major high-affinity receptor for the protective antigen (PA) component of the anthrax toxin; this interaction initiates receptor-mediated endocytosis and cytosolic delivery of bacterial enzymes in host cells, which underpins anthrax pathogenesis. Beyond its role in mediating toxin uptake, ANTXR2 is essential for extracellular matrix integrity, angiogenesis, and connective tissue maintenance, primarily through binding collagen IV and laminin and regulating matrix remodeling enzymes. Mutations in ANTXR2 cause autosomal recessive Hyaline Fibromatosis Syndrome (HFS), marked by severe fibrotic tissue abnormalities. The receptor consists of a von Willebrand factor A domain and an immunoglobulin-like domain critical for ligand binding and endocytosis. It is expressed broadly in human tissues. Drugs targeting this receptor are being investigated for anthrax treatment, exploiting its unique role as a toxin anchor, though interference with normal receptor functions poses safety risks.

Other names

Anthrax toxin receptor 2ANTXR2CMG2Capillary morphogenesis gene 2 proteinCapillary morphogenesis protein 2HFSJHFISHFLJ31074

Antitoxin drugs act by competitively inhibiting protective antigen (PA) binding to ANTXR2, blocking the toxin uptake mechanism and preventing cell intoxication