Antigens of membranous nephropathy and their schematic molecular structure.Exostosins are transmembrane proteins in the Golgi apparatus that have a short amino-terminal cytoplasmic tail (N), a single transmembrane domain (S), and a long globular catalytic C-terminal domain(C) within the Golgi lumen.NCAM1contains an amino-terminal tail (N), five immunoglobulin domains (IgG), two fibronectin type III domains (FNIII), a transmembrane domain (TM), and an intracellular region at the C terminal end.Sema3Bhas large Sema domain region, a plexin-semaphorin-integrin (PSI) domain, an Ig domain, and a short C terminal basic domain.NELL1 is characterized by an amino-terminal TSP-1-like (TSPN) domain, a coiled-coil (C-C) domain, two von Willebrand factor type C (VWC) domains, six EGF-like domains (E), and two VWC domains at the cytoplasmic end.THSD7A contains 11 trombospondin type-1 domains (TSD),an arginine-glycine-aspartic acid motif (RDG),a transmembrane domain(TM) and a C terminalintracellular end.PLA2R contains a cys-rich domain (Cys-R), a fibronectin type II domain (FNII),8 C-type lectin-like domains (CTLD),a transmembrane domain (TM), and a C terminal intracellular end. Shown is the predominant Ig subclass of the relevant antibodies and the main activated complement pathway.