Observing Microtubule End-Binding Proteins Fused to mKusabira Orange Fluorescent Protein at 100X Magnification
Because all eukaryotic cells depend on the integrity of microtubules and other cytoskeletal filaments to maintain their structure and function, many plants produce natural toxins aimed at disrupting the microtubule network as a means of self-defense. Taxol, for example, is a toxic substance produced by a species of the yew tree that increases microtubule polymerization by binding to the filament and stabilizing it. Other natural toxins, such as the colchicine produced by the meadow saffron, destabilize microtubules and hinder their polymerization. Both of these effects can be fatal to the affected cell, though in some circumstances, this can be beneficial to animals, as demonstrated by taxol, which is commonly used as a cancer medication. In the digital videos presented above, normal Gray fox lung fibroblast cells (FoLu line) are expressing monomeric Kusabira Orange fused to the microtubule end-binding protein, EB3.