3E1334 High-resolution structural determination of the cofilin-decorated actin filament by single-particle analysis of cryo-electron micrographs(3E Muscle 2,The 49th Annual Meeting of the Biophysical Society of Japan)

TheBiophysicalSociety of Japan General IncorporatedAssociation moleculcs with a single fi1arnent was not knorvn yet.Especially. it should be of great importancc to know the Iinear-density of interacting rnyosin heads along an actin fi]ament with respcct to the pheiiomena that the tai[ region ofa filaincnt strictly tbllows moving trace or thc prcceding region.in order to approach this theme, we have focused on the hydrophobicity around the Cys374 of actin molecule and found that an environmcntal-sensitive clye, PyMPO, would bc a good candidate for detecting an acto-myosin interaction.Here, we have succeeded to visualizc both HMM molecule and its binding sites along a single actin filament in the absencc of ATP under a conventional micrescope.The detailed characterizations and the Tcsults in the preseiice of ATP, i.e. moving filaments, will be discussed.3EI048P071YEI030 Takashi FuJ Sch.F)'ontier Biosciences, To understand bow myosin binds structure of actin-myosin 7A resolution density map ofactin-myosin II Sl density map structures and possible.The structure suggests that myosin undeTgoes a drastic confonnational change upon strongly binding to the actin fllament and that a myosin binds to two actin monomers,The high resolution strueure gave us a relative three dimensional arrangement between actin and myosin, suggesLing that thc mutations caused myopathic ilrness is highiy related to the residues fonnfng the actin-myosin interfaee.