Flashcards in Lab 9 Deck (6)
colchicine and cycloheximide.
Colchicine binds to free tubulin dimers and prevents the addition of dimers to microtubules.
Cycloheximide is a potent inhibitor of protein synthesis.
Deflagellate the algae in the beaker by
rapidly lowering the pH of the medium
extensions from the cell surface that consist of 9 doublets of microtubules, 2 central microtubules, plus several MAPs
Discuss, in a few sentences, how cycloheximide and colchicine affect flagellar regeneration
Cycloheximide is a potent inhibitor of protein synthesis so it acts to stop the entire process of micro tubular formation. As soon as it’s added flagella stop growing, so the only thing left in the solution is whatever managed to grow before cycloheximide was added. This means that flagella cannot at all regenerate in the presents of cycloheximide. Colchicine binds to free tubulin dimers and prevents the addition of dimers to microtubules. This means that the formation of microtubules are halted until the 5mls of of colchicine is used up by binding to the dimers, after that the dimers that are still being formed start making more microtubules again. Therefore the process of microtubule formation is briefly halted till colchicine is used then continues.
What was the purpose of collecting flagellar-length measurements for the original culture (non-deflagellated cells)?
added mainly to prove that the lugs iodine and medium I did not cause deflagration but rather the acid added caused deflagration