Large fluctuations in the disassembly rate of microtubules revealed by atomic force microscopy.

Details

Serval ID
serval:BIB_58679E1AEF31
Type
Article: article from journal or magazin.
Collection
Publications
Institution
Title
Large fluctuations in the disassembly rate of microtubules revealed by atomic force microscopy.
Journal
Ultramicroscopy
Author(s)
Thomson N.H., Kasas S., Riederer B.M., Catsicas S., Dietler G., Kulik A.J., Forró L.
ISSN
0304-3991 (Print)
ISSN-L
0304-3991
Publication state
Published
Issued date
2003
Volume
97
Number
1-4
Pages
239-247
Language
english
Abstract
Atomic force microscopy (AFM) in situ has been used to observe the cold disassembly dynamics of microtubules at a previously unrealised spatial resolution. Microtubules either electrostatically or covalently bound to aminosilane surfaces disassembled at room temperature under buffer solutions with no free tubulin present. This process was followed by taking sequential tapping-mode AFM images and measuring the change in the microtubule end position as a function of time, with an spatial accuracy down to +/-20nm and a temporal accuracy of +/-1s. As well as giving average disassembly rates on the order of 1-10 tubulin monomers per second, large fluctuations in the disassembly rate were revealed, indicating that the process is far from smooth and linear under these experimental conditions. The surface bound rates measured here are comparable to the rates for GMPCPP-tubulin microtubules free in solution, suggesting that inhibition of tubulin curvature through steric hindrance controls the average, relatively low disassembly rate. The large fluctuations in this rate are thought to be due to multiple pathways in the kinetics of disassembly with differing rate constants and/or stalling due to defects in the microtubule lattice. Microtubules that were covalently bound to the surface left behind the protofilaments covalently cross-linked to the aminosilane via glutaraldehyde during the disassembly process. Further work is needed to quantitatively assess the effects of surface binding on protofibril disassembly rates, reveal any differences in disassembly rates between the plus and minus ends and to enable assembly as well as disassembly to be imaged in the microscope fluid cell in real-time.
Keywords
Aluminum Silicates/chemistry, Animals, Glutaral, Microscopy, Atomic Force/methods, Microtubules/chemistry, Microtubules/metabolism, Swine, Telencephalon/ultrastructure, Tubulin/metabolism
Pubmed
Web of science
Create date
24/01/2008 14:34
Last modification date
20/08/2019 14:12
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