The principal constituent of a polyhedral protein lattice that coats eukaryotic cell membranes (vesicles) and coated pits and appears to be involved in protein secretion. This protein also occurs in synaptic vesicles. [L. clathri, lattice]
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clath·rin 'klath-rin n the major component protein of a cagelike polyhedral molecular arrangement that forms on the cytoplasmic side of a cell's plasma membrane and coats the endocytotic vesicles which bud off from the membrane
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clath·rin (klathґrin) a protein consisting of three limbs, each composed of a heavy (180 kD) and a light (about 35 kD) chain, in a triskelion arrangement; it coats the cytoplasmic face of coated pits (q.v.) in receptor-mediated endocytosis. Clathrin-coated vesicles are also involved in retrieval of synaptic vesicle membrane following neurotransmitter release and in vesicle formation on the trans-Golgi network and endosomes. The coat depolymerizes after the vesicle buds from the membrane and the clathrin units are reused.Medical dictionary. 2011.