Integral component of basement membranes. Component of the glomerular basement membrane (GBM), responsible for the fixed negative electrostatic membrane charge, and which provides a barrier which is both size- and charge-selective. It serves as an attachment substrate for cells. Plays essential roles in vascularization. Critical for normal heart development and for regulating the vascular response to injury. Also required for avascular cartilage development (By similarity). Endorepellin in an anti-angiogenic and anti-tumor peptide that inhibits endothelial cell migration, collagen-induced endothelial tube morphogenesis and blood vessel growth in the chorioallantoic membrane. Blocks endothelial cell adhesion to fibronectin and type I collagen. Anti-tumor agent in neovascularization. Interaction with its ligand, integrin alpha2/beta1, is required for the anti-angiogenic properties. Evokes a reduction in phosphorylation of receptor tyrosine kinases via alpha2/beta1 integrin-mediated activation of the tyrosine phosphatase, PTPN6 (By similarity). The LG3 peptide has anti-angiogenic properties that require binding of calcium ions for full activity. Purified perlecan has a strong tendency to aggregate in dimers or stellate structures. It interacts with other basement membrane components such as laminin, prolargin and collagen type IV. Interacts with COL13A1, FGFBP1 and VWA1. Interacts (via C-terminus) with ECM1 (via C-terminus) (By similarity). Found in the basement membranes. Proteolytic processing produces the C-terminal angiogenic peptide, endorepellin. This peptide can be further processed to produce the LG3 peptide (By similarity). N- and O-glycosylated; contains 3 heparan sulfate chains. The LG3 peptide contains at least three and up to five potential O-glycosylation sites and no N-glycosylation (By similarity). About 40% of perlecan null mice die at 10.5 dpc, the rest die just after birth. Embryonic percelan-null mice exhibit cardiac abnormalities including mechanical instability in the early stages of development (10.5 dpc) with lower amounts of critical basement membrane components, collagen IV and lamanins. Basement membranes are absent in cardiomyocytes whereas adherens junctions formed and matured around 9.5 dpc. Mice also have skeletal dysplasia characterized by micromelia with broad and bowed long bones, narrow thorax and craniofacial abnormalities. Cartilage matrix containd reduced and disorganized collagen fibrils and glycosaminoglycans. In cartilage, proliferation of chondrocytes was reduced and the prehypertrophic zone was diminished.