Steady state EB cap size fluctuations are determined by stochastic microtubule growth and maturation Journal Article


Author(s): Rickman, Jamie; Duellberg, Christian; Cade, Nicholas I; Griffin, Lewis D; Surrey, Thomas
Article Title: Steady state EB cap size fluctuations are determined by stochastic microtubule growth and maturation
Affiliation IST Austria
Abstract: Growing microtubules are protected from depolymerization by the presence of a GTP or GDP/Pi cap. End-binding proteins of the EB1 family bind to the stabilizing cap, allowing monitoring of its size in real time. The cap size has been shown to correlate with instantaneous microtubule stability. Here we have quantitatively characterized the properties of cap size fluctuations during steadystate growth and have developed a theory predicting their timescale and amplitude from the kinetics of microtubule growth and cap maturation. In contrast to growth speed fluctuations, cap size fluctuations show a characteristic timescale, which is defined by the lifetime of the cap sites. Growth fluctuations affect the amplitude of cap size fluctuations; however, cap size does not affect growth speed, indicating that microtubules are far from instability during most of their time of growth. Our theory provides the basis for a quantitative understanding of microtubule stability fluctuations during steady-state growth.
Keywords: Microtubules; Biochemical network; dynamic instability; EB1; GTP cap
Journal Title: PNAS
Volume: 114
Issue 13
ISSN: 1091-6490
Publisher: National Academy of Sciences  
Date Published: 2017-03-28
Start Page: 3427
End Page: 3432
URL:
DOI: 10.1073/pnas.1620274114
Open access: yes (repository)