title: Conformation of a clathrin triskelion in solution.
abstract: A principal component in the protein coats of certain post-golgi and endocytic vesicles is clathrin, which appears as a three-legged heteropolymer (known as a triskelion) that assembles into polyhedral cages principally made up of pentagonal and hexagonal faces. In vitro, this assembly depends upon the pH, with cages forming more readily at low pH and less readily at high pH. We have developed procedures, on the basis of static and dynamic light scattering, to determine the radius of gyration, R(g), and hydrodynamic radius, R(H), of isolated triskelia, under conditions where cage assembly occurs. Calculations based on rigid molecular bead models of a triskelion show that the measured values can be accounted for by bending the legs and a puckering at the vertex. We also show that the values of R(g) and R(H) measured for clathrin triskelia in solution are qualitatively consistent with the conformation of a triskelion in a "D6 barrel" cage assembly measured by cryoelectron microscopy.
authors: Laboratory of Integrative and Medical Biophysics, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland 20892, USA.
authors: Matthew L
authors: ML
authors: Ferguson
authors: Kondury
authors: K
authors: Prasad
authors: Dan L
authors: DL
authors: Sackett
authors: Hacène
authors: H
authors: Boukari
authors: Eileen M
authors: EM
authors: Lafer
authors: Ralph
authors: R
authors: Nossal