Curriculum
Module 05 · 65 min

Cytoskeleton & Cell Motility

Actin, microtubules, intermediate filaments — and the motors that walk on them.

CoreClinicalResearch
Topics

What this module covers

  • 01Actin polymerisation: ATP/ADP states, treadmilling, Arp2/3, formins
  • 02Microtubule dynamic instability, GTP cap, +TIPs, MAPs
  • 03Intermediate filaments (keratins, vimentin, lamins, neurofilaments, desmin)
  • 04Motors: myosin, kinesin, dynein — directionality and cargoes
  • 05Lamellipodia vs filopodia; Rho/Rac/Cdc42 GTPases in migration
  • 06Cilia and flagella; ciliopathies
Deep dives

Lesson sub-pages

advanced 25 min· 3 refs
Actin treadmilling and the motile cell
How a polymer that hydrolyses ATP becomes a force-generating machine — and the drugs that break it.
Learning objectives

By the end of this module you will be able to

  • L01Match a cytoskeletal drug (cytochalasin, latrunculin, paclitaxel, vinblastine, colchicine) to its mechanism.
  • L02Predict the consequence of a mutation in a specific intermediate filament for a specific tissue.
  • L03Explain why ciliary defects produce a remarkably consistent set of organ malformations.
Expected takeaways

What you should walk away believing

  • →The cytoskeleton is mechanically active and biochemically signalling — not a 'scaffold'.
  • →Intermediate filament mutations produce tissue-specific fragility (skin, muscle, neuron, nucleus).
  • →Microtubule-targeting drugs are central to oncology and gout; resistance often emerges via β-tubulin isoforms or efflux.
Core summary

At the Core level

The cytoskeleton is three filament systems with overlapping roles: actin for shape and locomotion (sub-second), microtubules for transport and division (seconds-minutes), intermediate filaments for mechanical resilience (hours-days). Each is dynamic, regulated, and drugged at the bedside.

Evidence-graded claims

Claims, scored A–F

A
Microtubules undergo dynamic instability
Mitchison & Kirschner, foundational.
B
Paclitaxel resistance often involves β-tubulin isotype switching
Supported but tumour-context-dependent.
F
Cilia are vestigial in adult humans
Primary cilia are critical signaling hubs (Hedgehog, PDGFR) on most cells.
Quiz

Check your understanding

Q1. Paclitaxel kills cells by:
Q2. Which Rho-family GTPase drives lamellipodial actin protrusion?
Flashcards

Lock it in

1 / 4
Front
Three intermediate-filament diseases and tissues?
Click to flip
Suggested reading

Primary literature

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Organelles & the Secretory Pathway
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Cell Junctions & the Extracellular Matrix