BIOL 2021 Chapter Notes - Chapter 16.9: Intermediate Filament, Cytoskeleton, Microtubule
11 Feb 2018
School
Department
Course
Professor
Document Summary
Green is microtubules, actin is red; green is spindle microtubules, red is intermediate filaments. The cytoskeleton is composed of filaments for strength, shape, and cell movement. Actin filaments: provide cell surface shape and locomotion. Microtubules: used for intracellular transport, organelle location, and mitotic spindles. The cytoskeleton can be either dynamic or stable, depending on what the cell requires. Dynamic structure is used for cytoskeletal organization in cell division (left) Stable structure is used for organization of the cytoskeleton in polarized epithelial cells (right) The cytoskeleton is constantly in flux because the components are assembled of small subunits. These subunits are held together by non-covalent interactions so that rapid changes can take place. Small subunits create a protofilament: one row of connected subunits. Helical filament: formed by wrapping protofilaments around each other. Accessory proteins control the assembly and disassembly of subunits and link filaments to each other.
