Microtubules

Question 1

How do you purify microtubules?

Answer 1

Get from brain and lower temp to disrupt hydrophobic interactions and make MTs fall apart

Question 2

Microtubules=heterodimer…of what subunits and what do they do? What do N and E sites refer to?

Answer 2

A and B tubulin. A is minus end and has GTP binding pocket closed= N-site for NON-exchangable. B is plus end. E-site for exchangable GTP binding pocket opened

Question 3

how many protofilaments in MT

Answer 3

13

Question 4

Kinesin is?

Answer 4

anterograde microtubule motor

Question 5

Dynein is?

Answer 5

retrograde motor

Question 6

which drugs depolymerize micro network?

Answer 6

colchicine and nocodazole, destroy it

Question 7

which drugs polymerize?

Answer 7

vinca alkaloids and taxol

Question 8

what is dynamic instability? whats rescue and catastrophe? how does it explain dropping # but increasing length?

Answer 8

rate of GTP addition/capping RESCUE vs. GTP hydrolysis CATASTROPHE, grows if capping is higher rate

Question 9

where does + end and - end attach during cell division?

Answer 9

+ end kineticore, - end centrosome