Length regulation of microtubules by molecular motors: exact solution and density profiles

Arita, Chikashi; Lück, Alexander; Santen, Ludger

doi:10.1088/1742-5468/2015/06/p06027

Cited by 8 publications

(5 citation statements)

References 27 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…We now discuss a phenomenological approach to the dynamics of the MTOC position C. We consider that the motion of the MTOC is eectively governed by a random walk with leftward and rightward hopping rates, qρ + C and qρ + L−C , respectively, with some factor q. This interpretation leads to the stationary distribution as (18) with normalization Z. Furthermore this expression is approximated in the localization phase as in the limit L → ∞, due to equation (17).…”

Section: Dynamics Of the Mtoc Positionmentioning

confidence: 99%

See 1 more Smart Citation

Localization of a microtubule organizing center by kinesin motors

et al. 2017

Self Cite

View full text Add to dashboard Cite

The microtubule (MT) motor Kip3p is very processive kinesin that promotes catastrophes and pausing in particular on cortical contact. These properties explain the role of Kip3p in positioning the mitotic spindle in budding yeast and potentially other processes controlled by kinesin-8 family members. We present a theoretical approach to positioning of a MT network in a cell. In order to explore the underlying mechanism we introduce an idealized system of two MTs connected by a microtubule organizing center (MTOC). The dynamics of Kip3p is modeled by interacting stochastic particles, which allows us to study the effects of motor-induced depolymerization under spatial confinement. We find that localization in the middle of the system is realized in a parameter regime where the motor densities on the MTs are increasing with the distance from the MTOC. Localization at an asymmetric position is also possible by tuning the kinesin input rates at the MT minus ends or attachment rates depending on different compartments of the cell.

show abstract

Section: Dynamics Of the Mtoc Positionmentioning

confidence: 99%

“…The exclusion process is one of the best studied stochastic interacting particle systems far from equilibrium. It often serves as a reference model for stochastic transport and is exactly solvable [15], even in some cases of varying system size [16][17][18].…”

Section: Introductionmentioning

confidence: 99%

Localization of a microtubule organizing center by kinesin motors

et al. 2017

Self Cite

View full text Add to dashboard Cite

show abstract

“…The MT length regulation mechanism has been theoretically studied over the last two decades 9 10 29 30 31 32 . More recently, the interplay between polymerization kinetics and motor-induced depolymerization has been incorporated into the stochastic models for the length regulation of MTs and other active biopolymers 9 10 .…”

Section: Modelmentioning

confidence: 99%

Tracking of plus-ends reveals microtubule functional diversity in different cell types

Shaebani

Pasula

Ott

et al. 2016

Sci Rep

Self Cite

View full text Add to dashboard Cite

Many cellular processes are tightly connected to the dynamics of microtubules (MTs). While in neuronal axons MTs mainly regulate intracellular trafficking, they participate in cytoskeleton reorganization in many other eukaryotic cells, enabling the cell to efficiently adapt to changes in the environment. We show that the functional differences of MTs in different cell types and regions is reflected in the dynamic properties of MT tips. Using plus-end tracking proteins EB1 to monitor growing MT plus-ends, we show that MT dynamics and life cycle in axons of human neurons significantly differ from that of fibroblast cells. The density of plus-ends, as well as the rescue and catastrophe frequencies increase while the growth rate decreases toward the fibroblast cell margin. This results in a rather stable filamentous network structure and maintains the connection between nucleus and membrane. In contrast, plus-ends are uniformly distributed along the axons and exhibit diverse polymerization run times and spatially homogeneous rescue and catastrophe frequencies, leading to MT segments of various lengths. The probability distributions of the excursion length of polymerization and the MT length both follow nearly exponential tails, in agreement with the analytical predictions of a two-state model of MT dynamics.

show abstract

“…In a further interesting line of research, extensions of the TASEP to dynamic lattices have been developed [12][13][14][15][16][17][18][19][20][21][22][23][24][25][26][27][28]. On the one hand, motivated by the transport of vesicles along microtubules that facilitate growth of fungal hyphae, or by growth of flagellar filaments, TASEP models have been considered in which a particle that reaches the end of the lattice may extend it by a single site [12,14,15,17,22].…”

Section: Introductionmentioning

confidence: 99%

Self-organized system-size oscillation of a stochastic lattice-gas model

2018

View full text Add to dashboard Cite

The totally asymmetric simple exclusion process (TASEP) is a paradigmatic stochastic model for nonequilibrium physics, and has been successfully applied to describe active transport of molecular motors along cytoskeletal filaments. Building on this simple model, we consider a two-lane lattice-gas model that couples directed transport (TASEP) to diffusive motion in a semiclosed geometry, and simultaneously accounts for spontaneous growth and particle-induced shrinkage of the system's size. This particular extension of the TASEP is motivated by the question of how active transport and diffusion might influence length regulation in confined systems. Surprisingly, we find that the size of our intrinsically stochastic system exhibits robust temporal patterns over a broad range of growth rates. More specifically, when particle diffusion is slow relative to the shrinkage dynamics, we observe quasiperiodic changes in length. We provide an intuitive explanation for the occurrence of these self-organized temporal patterns, which is based on the imbalance between the diffusion and shrinkage speed in the confined geometry. Finally, we formulate an effective theory for the oscillatory regime, which explains the origin of the oscillations and correctly predicts the dependence of key quantities, such as the oscillation frequency, on the growth rate.

show abstract

Length regulation of microtubules by molecular motors: exact solution and density profiles

Cited by 8 publications

References 27 publications

Localization of a microtubule organizing center by kinesin motors

Localization of a microtubule organizing center by kinesin motors

Tracking of plus-ends reveals microtubule functional diversity in different cell types

Self-organized system-size oscillation of a stochastic lattice-gas model

Contact Info

Product

Resources

About