Macromolecular organization and functional architecture of basement membranes.
Basement membranes (BMs) are extracellular laminar matrices produced by endothelial and epithelial cells. They are composed by three major intrinsic macromolecules: type IV collagen, laminin and heparan sulfate proteoglycan (HSP), and by two major extrinsic ones: fibronectin and type V collagen. The intrinsic components are assembled in a three-dimensional network (type IV collagen) to which cells stick (by laminin) and through which (HSP) they interact with the stromal compartment. The BM is a barrier to be crossed by any cell that leaves the stroma to enter into the circulation or vice versa. Metastatic tumor cells secrete a protease which specifically degrades the BM collagen and some evidence suggests that the same enzyme is used also by normal monocytes.
D000818:Animals; D001485:Basement Membrane / Q000502:physiology / Q000648:ultrastructure*; D011508:Chondroitin Sulfate Proteoglycans / Q000378:metabolism; D003094:Collagen / Q000378:metabolism; D005353:Fibronectins / Q000378:metabolism; D019812:Heparan Sulfate Proteoglycans; D006497:Heparan Sulfate / Q000378:metabolism; D007678:Kidney Glomerulus / Q000648:ultrastructure; D007797:Laminin / Q000378:metabolism; D051379:Mice; D009369:Neoplasms / Q000648:ultrastructure
D011508:Chondroitin Sulfate Proteoglycans; D003094:Collagen; D005353:Fibronectins; D019812:Heparan Sulfate Proteoglycans; D006497:Heparan Sulfate; D007797:Laminin