MCD BIO 165A Lecture Notes - Lecture 9: Tubulin, Motility, Microtubule

• School: UCLA
• Department: Molecular, Cell, and Developmental Biology
• Course: MCD BIO 165A
• Professor: arispe

Document Summary

Intracellular motility mostly associated with microtubules: microtubules critical for cell division, cell structure maintenance & cell response to physical forces. Drug depolymerizing microtubules -> cell falls apart, e(cid:448)e(cid:374) if the(cid:396)e"s a(cid:272)ti(cid:374) & if. Microtubule overview: a tubulin + b tubulin -> dimer -> protofilaments (column) -> microtubules, gtp required for a- & b-tubulin to form dimers. Gtp hydrolyzed -> depolymerization: polymerization promoted by gamma tubulin. Present in high concentration around centrosomes & in area associated with golgi in centrioles: columns are called protofilaments. 13 of them form sheet -> folds -> microtubule (~24nm: grows by adding gtp-bound a- & b-tubulin, growing & shrinking -> dynamic instability. If microtubule loses gdp -> catastrophe, protofilaments falls apart: gtp cap prevents depolymerization, microtubules dependent on other microtubule associated proteins -> architecture & dynamic of microtubules. Microtubules in there far apart, because of map2. D has de(cid:374)se(cid:396) dist(cid:396)i(cid:271)utio(cid:374) of (cid:373)i(cid:272)(cid:396)otu(cid:271)ule tha(cid:374) c, (cid:271)e(cid:272)ause the(cid:455) do(cid:374)"t ha(cid:448)e map4: other proteins.