Clatharin is a protein which is present on the cystolic (inside) surface of a membrane and very important in intracellular vesicular trafficking. It forms an intracelular vesicle by budding off the membrane via endocytosis. Clathrin also coats COPI & COPII vesicles which bud off rom the Golgi and Endoplasmic Reticulum respectiviely. The structure of Clathrin itself consists of three large and three small polypeptide chains that form a three-legged structure called a triskelion. Triskelions assemble into a basketlike structure of pentagons and hexagons to form the Clathrin-coated pits on the cystolic surface of membranes.
- ↑ Molecular Biology of The Cell, 5th Edition, Alberts et al, pg 754-756.