Atomic Structure of Tubulin.
(Ribbon and Space Filling Models)
Molecular Structure of a Nucleoside Triphosphate(ATP or GTP)
TEM of Self Assembled MTs and MTs Assembled on a Centrosome “template”
Microtubules and Motors: MT polymer ratchets and motor proteins.
F ~ 1-10pN
F ~1-50pN
Filament Assembly and Force Production.
Flux. (Margolis and Wilson, 1978; Mitchison, 1989).
Dynamic Instability.(Mitchison and Kirschner, 1984).
Microtubule Polymer Dynamics
GTP hydrolysis and Dynamic Instability at Steady State.
Microtubule Dynamics in Anaphase A
Metaphase
Anaphase A
Anaphase B
Kinetochore motility - Pacman versus poleward flux.
Mechanism of Chromosome Movement.
MT dynamics in Anaphase B
Metaphase
Anaphase A
Anaphase B
Anaphase B Spindle Elongation
1. A motor-dependent sliding filament mechanism generates force to push the poles apart.
2. Poleward flux acts as a regulatory switch.