Question

The following drugs affect the cytoskeleton. For each of the drugs below, indicate (A) which cytoskeleton is affected, (B), If polymerization or depolymerization is affected, and (C) an example of a process that would be affected by the drug. (6 pt)

Vinblastine aggregrates tubulin dimers bound to GDP

Acrylamide cause loss of tetramer interactions

Cytochalasin D prevents actin-GTP from binding the plus end

Answer 1

Vinblastine affects microtubule polymerization and causes depolymerization at minus ends of microtubules. At a concentration between 0.1 and 0.4 micromolar, drug depolymerizes minus ends without significantly affecting microtubules at plus ends, thus increasing the dynamicity at minus ends.. Thus mitosisgets affected due to altered function of mitotic spindles.

Treatment with acrylamide causes collapse of vimentin filaments (intermediate filaments) and vimentin polymerization is affected. For example, acrylamide treatment to a cell affecting vimentin can help us to study viral infection and its movement through the endocytic pathway via vimentin network.

Cytochalasin D affects actin polymerization, affecting actin elongation. Usage of an inhibitor like cytochalasin can help researchers to understand several biological processes where actin plays an important role (eg: cell division)