Question

You have discovered a single cellular eukaryotic organism that has very little vesicle trafficking. You suspect that this may be due to the relatively few formed microtubules that are observed in this species. Upon close examination, you find the microtubules that are present are unusually stable. When looking at an amino acid comparison with human alpha and beta tubulin, you notice that the alpha tubulin is identical, but the beta tubulin is different in the region responsible for GTP hydrolysis. You isolated the heterodimer subunits from this new species and put them in a cell free system in a GTP bound form of the heterodimer along with centrosome nucleation sites. How would the dynamics be different from human heterodimer subunits in the same situation

Answer 1

Micro-tubules from the freshly revealed species are strangely constant, perhaps its beta tubulin sub-unit doesn’t experience GTP hydrolysis certainly. GTP assured that the tubulin is anatomically more constant than GTP bound tubulin and permits polymerization to take their place. However, the micro-tubules of new species’ would be less liable to disaster and they might grow to a longer distance than standard cellular micro-tubules.