Perlecan

Part of speech: noun

Definitions

1. A large protein carrying heparan sulfate chains that forms a key structural component of basement membranes in animal tissues
2. A big proteoglycan molecule with sugar side chains that helps build the supporting layer beneath epithelial and endothelial cells
3. A major extracellular matrix molecule, rich in heparan sulfate, that gives structure and filtering properties to basement membranes

Etymology: Perlecan is a modern scientific coinage, so its history is recent and documented in the scientific literature rather than in older dictionaries. The name most likely combines "perle," the French and German word for pearl, with a suffix, a reference to the beaded appearance the molecule shows under the microscope. That fits its role: it is a large protein carrying many sugar chains, found in the thin sheets of tissue that line blood vessels and wrap around muscle and nerve cells. The ending "-can" is shared with a family of related molecules. Aggrecan and versican, both large proteoglycans in connective tissue, follow the same naming pattern. The suffix signals membership in a group of proteins that carry sugar chains, so the name tells a researcher what kind of molecule to expect before any structure is studied.