BIOL 1111 Lecture Notes - Brownian Ratchet, Myosin, Microfilament

• School: University of Windsor
• Department: Biological Sciences
• Course: BIOL 1111
• Professor: Habetler

Document Summary

Taxol inhibits cell division by slowing microtubule disassembly. Viscosity: f=g v v = f/g (applying constant force results in constant speed) diffusion: larger proteins, organelles cannot diffuse due to random thermal motion due to presence of cytoskeleton sol"n: to use motor proteins to use cytoskeletal network! Gtpase for polymerization actin monomers support myosin-based motility/contractility. Atpase structural/mechanical support dimers non-polar not used as tracks structural/mechanical function only most flexible. B always towards (+) end; a to (-) end. Gdp binding: depol. (causes end of protofilament to bow ) splaying. Dynamic instability: alternating between gtp and gdp at plus end results in alternate growth (rescue) and shrinkage (catasprophe) rapid growth . A/b dimers used up concentration dips below cc slowed growth (+) caps have enough time to hydrolyze gtp . Catastrophe (depol) concentration eventually regains above cc . Gdp-gtp exchange is necessary for readdition to filament. Taxol: keeps all microtubules in polymer form (prevents catastrophe)