8.592 - HST.452J (Spring 2026)

Statistical Physics in Biology

Lecture 13

Microtubules

1. Filaments in the cycloskeleton and their function:
   • Actin filaments
     • Structure
     • Treadmilling and regulation
   • Intermediate filaments
   • Microtubules
   • Video
2. Microtubule structure:
• Tubulin subunits
• Protofilaments, nucleation and growth
• Polarity
3. Dynamic Instability [Mitchison & Kirchner, Nature 312, 237 (1984)] (video)
• Model of growth and regulation (Leibler, et al)   [JCB 118, 1097 (1992)] [PRL70, 1347 (1993).]
• Model of catastrophes [H. Flyvbjerg, TE Holy, & S. Leibler, PRL73, 2372 (1994).]
4. Search strategy
   • Mitosis
   • Condensation of RecA on ssDNA as a tool for computation by stochastic assembly
   • Relation to kinetic proof-reading
     • Fidelity of replication (Hopfield 74)

(Lecture notes)

Some related links

• Nonosimulations of the cytoskeleton (a PhD thesis by Christopher Betts)