GTP (100mM Stock)

Question 1: Does GTP need to be included in tubulin buffers prepared for reconstituting and storing tubulin if the tubulin will not be used for polymerization?

Answer 1: Cytoskeleton&rsquo, s tubulin proteins are lyophilized in a buffer that contains 1 mM GTP, so omitting additional GTP (Cat. #BST06) in the reconstitution buffer can be done if the tubulin will not be used for polymerization. However, this is not recommended. Under most preparation conditions, GTP is required for tubulin stability and for the formation of microtubules in vivo and in vitro and we recommend adding fresh GTP (1 mM) to the PEM buffer used for reconstitution and polymerization.

Question 2: How long is GTP-containing tubulin buffer stable for when stored on ice the day of the experiment?

Answer 2: Buffers that contain GTP (Cat. #BST06) should not be kept longer than 2 hours on ice. After this time, GTP-supplemented buffers should be discarded. Do not attempt to freeze and re-use these buffers.