Tubulin glycerol buffer: cushion buffer
Product Uses Include
- Promote tubulin polymerization
- Use as a microtubule cushion buffer
Material
Formerly called Microtubule Cushion Buffer. Contains BST01 in 60% [v/v] glycerol. When diluted in G-PEM to a final concentration of e.g. 5% glycerol, it can be used to promote tubulin polymerization. It is also used to separate microtubules from non-polymerized tubulin by centrifugation and to separate microtubule bound MAPs from non-microtubule-binding proteins.
For product Datasheets and MSDSs please click on the PDF links below. For additional information, click on the FAQs tab above or contact our Technical Support department at tservice@cytoskeleton.com
Question 1: Can the tubulin glycerol buffer be used to separate microtubules from non-polymerized tubulin and/or non-MAP proteins?
Answer 1: Yes, the tubulin glycerol buffer (Cat. # BST05; aka cushion buffer) can be used undiluted as a 60% glycerol cushion. Microtubules should be layered onto a 5X volume of cushion buffer and centrifuged at 100,000 x g for 30 minutes. The microtubules will pellet through the cushion and leave any unpolymerized tubulin and non-MAP proteins at the cushion buffer interface. The cushion can be gently removed and the microtubule pellet resuspended and analyzed as required. It is important to note that the cushion buffer should be supplemented with reagents that are necessary for tubulin/microtubule stability (e.g., 1 mM GTP and 10 μM taxol).
Question 2: What is the optimal concentration of glycerol to include for enhancement of polymerization?
Answer 2: Glycerol is often added to a final concentration of 5 - 10% to enhance polymerization; however, glycerol is not necessary for the maintenance of biologically active tubulin. We also do not recommend adding high concentrations of glycerol (10-20%) with taxol. Either glycerol or taxol alone should be used to enhance tubulin polymerization. As tubulin concentrations are reduced (<2 mg/ml), the glycerol concentration can be increased up to 20%, but we do not recommend using above this concentration. A high glycerol concentration can lead to a ceiling effect and mask other enhancers, so if testing polymerization enhancers, we recommend omitting glycerol in the experimental drug conditions. Glycerol is ideal as a treatment standard against which test enhancers can be evaluated.
If you have any questions concerning this product, please contact our Technical Service department at tservice@cytoskeleton.com
