BIOL 2020 Lecture Notes - Lecture 24: Vinculin, Filamin, Nissan L Engine
Document Summary
Filamin folds actin filaments at right angles: f has a right angle, villin holds filaments together in parallels, villin has a double l so it is parallel. Secures microfilament to the membrane so that the membrane follows actin movement. Cell locomotion: mostly a good thing but sometimes a very bad thing, ex. Steps to locomotion (all involved actin): extension, wasp activates arp2/3 complex, nucleation on the sides of filaments, microfilaments will grow. Profilin will recharge monomers by exchanging adp to atp: barbed ends elongate: membrane is pushed forward, capping protein terminates elongation, old f-actin capped to influence growth direction, cofilin will depolymerize the pointed end of older microfilaments. Adp to atp: adhesion, black box is adhesion point, where cell is touching the surface, so it can push off, semi- permanent attachment. Leading edge is the lamellipodium (flat and close to the surface, fans out: the direction the cell is going, actin fibers underneath the surface and pushing the lamellipodium out.