2016/03/28

The secret of surface chemistry

One of my research projects is about the polymerization of the protein tubulin to microtubules, which are long, thin and stiff rods in our cells. They are important for cell transport, division and shape. Microtubules can grow and shrink in our cells; so far, most research papers look at microtubules with motor proteins or networks which are stabilized with taxol, which is a cancer medication and inhibits microtubule growth and shrinkage. (Cell death is triggered when the microtubules' dynamics are stopped, so taxol treated cancer cells die.)


Microtubule / tubulin relation (wikipedia). The monomers (tubulin) polymerize to form a microtubule.

During the last few weeks, we hoped to see microtubules being dynamic, but the tubulin (the monomers) were sticking together in large chunks. Now we carried out exactly the same procedure and coated the surface of the chamber, which contains the tubulin solution, with a polymer that does not bind to tubulin. Otherwise, the tubulin would be exposed to glass and in general, glass really likes proteins and they stick together. Thus, the effective concentration of tubulin in our solution would be lower than with coating since no proteins are absorbed by the polymers. 

And the polymer coating changed a lot! We're still looking at some chunks, but the rest is a nice and homogeneous microtubule network :)