Making seeds

We want to look at dynamic microtubules which are a common biopolymer in cells. So far, our microtubules just grow, but don't shrink, but we want to have both types of dynamics in our studies. To get there, we left out the stabilizing chemical and we ended up with clumps only and no network.

After talking to experts in the field of microtubules, it turned out that seeds could be helpful. The microtubules would just start growing on them. Thus, we had to made those seeds (made of tiny stable microtubules) which took seven hours! But after lots of centrifuging and incubating, the last step involved freezing the sample tubes (the small colorful tubes at the bottom of the photo) in liquid nitrogen which is great fun:

Just slowly freezing the protein would have led to the depolymerization of the seeds, i.e. we would have lots of protein in solution, but no seeds. The liquid nitrogen freezes the seeds so quickly that there's no time to disassemble. Afterwards we store them at -80°C so that no thawing happens.