Mechanism of Calponin Stabilization of Cross-Linked Actin Networks

Jensen, Mikkel H.; Morris, Eliza J.; Gallant, Cynthia; Morgan, Kathleen G.; Weitz, David A.; Moore, Jeffrey R.

doi:10.1016/j.bpj.2013.12.042

Cited by 24 publications

(30 citation statements)

References 52 publications

(77 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…From its known function as a stabilizer of actin filaments , it was not surprising that we identified Cnn3 as being localized to the apical lining of the NE in close vicinity to the adhesion junctions formed by beta‐Catenin and N ‐Cadherin. It is believed that a rearrangement of the actin cytoskeleton at the apical side of the NE is one crucial step during correct neural tube folding as it appears to be a prerequisite in changing the shape of the neural folds from a flat to a more concave shape and, as mentioned before, many cytoskeleton regulators have been identified to cause cranial neural tube closure defects when disturbances in their expression or function are present .…”

Section: Discussionmentioning

confidence: 99%

Cnn3 regulates neural tube morphogenesis and neuronal stem cell properties

Junghans

Herzog

2017

The FEBS Journal

View full text Add to dashboard Cite

Calponin 3 (Cnn3) is a member of the Cnn family of actin-binding molecules that is highly expressed in the mammalian brain and has been shown to control dendritic spine morphology, density, and plasticity by regulating actin cytoskeletal reorganization and dynamics. However, little is known about the role of Cnn3 during embryonic development. In this study, we analyzed mutant animals deficient in Cnn3 to gain a better understanding of its role in brain morphogenesis. Embryos lacking Cnn3 exhibited massive malformation of the developing brain including exoencephaly, closure defects at the rostral neural tube, and strong enlargement of brain tissue. In wild-type animals, we found Cnn3 being localized to the apical lining of the neuroepithelium in close vicinity to beta-Catenin and N-cadherin. By performing immunohistochemistry on beta-Catenin and p-Smad, and furthermore taking advantage of Wnt-reporter animals, we provide evidence that the loss of Cnn3 during development can affect signaling pathways crucial for correct morphogenesis of the neural tube. In addition, we used embryonic neurosphere cultures to investigate the role of Cnn3 in embryonic neuronal stem cells (NSC). Here, we observed that Cnn3 deficiency in NSCs increased the number of newly formed neurospheres and increased neurosphere size without perturbing their differentiation potential. Together, our study provides evidence for an important role of Cnn3 during development of the embryonic brain and in regulating NSC function.

show abstract

Section: Discussionmentioning

confidence: 99%

Cnn3 regulates neural tube morphogenesis and neuronal stem cell properties

Junghans

Herzog

2017

The FEBS Journal

View full text Add to dashboard Cite

show abstract

“…Depending on the local cross-linker protein abundance in the cell, turnover kinetics on the order of 1 μm of filament within ∼1 minute can be achieved, a rate at which treadmilling could become a contributing factor to cellular retrograde flow in the lamellipodium (Ponti et al, 2004; Watanabe and Mitchison, 2002). Additionally, filament structural changes generated by side-binding proteins may also play a more active role in the identity and turnover of actin-based sub-cellular structures than previously thought, by regulating processes such as branching and fragmentation (Hansen et al, 2013) or network mechanics (Jensen et al, 2014). Given the vast number of side-binding proteins, kinetic modulation via structural alteration may be a general regulatory mechanism of actin dynamics.…”

Section: Discussionmentioning

confidence: 99%

Side-binding proteins modulate actin filament dynamics

Crevenna

Arciniega

Dupont

et al. 2014

Preprint

View full text Add to dashboard Cite

Actin filament dynamics govern many key physiological processes from cell motility to tissue morphogenesis. A central feature of actin dynamics is the capacity of filaments to polymerize and depolymerize at their ends in response to cellular conditions. It is currently thought that filament kinetics can be described by a single rate constant for each end. In this study, using direct visualization of single actin filament elongation, we show that actin polymerization kinetics at both filament ends are strongly influenced by the binding of proteins to the lateral filament surface. We also show that the pointed-end has a nonelongating state that dominates the observed filament kinetic asymmetry. Estimates of flexibility as well as effects on fragmentation and growth suggest that the observed kinetic diversity arises from structural alteration. Tuning elongation kinetics by exploiting the malleability of the filament structure may be a ubiquitous mechanism to generate a rich variety of cellular actin dynamics.

show abstract

“…the expectation value L 0 c and standard variance ∆, where the variance can be controlled in experiments. 11 The mean length L 0 c is related to the number density of crosslinks n via L 0 c ∼ n −1/3 . Free energy of transient filament network can be obtained by adding the contributions from all the sub-networks of different mesh size:…”

Section: Polydisperse Networkmentioning

confidence: 99%

Fluidization of Transient Filament Networks

Meng

Terentjev

2018

Macromolecules

View full text Add to dashboard Cite

Stiff or semiflexible filaments can be crosslinked to form a network structure with unusual mechanical properties, if the crosslinks at network junctions have the ability to dynamically break and reform. The characteristic rheology, arising from the competition of plasticity from the transient crosslinks and nonlinear elasticity from the filament network, has been widely tested in experiments. Though the responses of a transient filament network under small deformations are relatively well understood by analyzing its linear viscoelasticity, a continuum theory adaptable for finite or large deformations is still absent. Here we develop a model for transient filament networks under arbitrary deformations, which is based on the crosslink dynamics and the macroscopic system tracking the continuously reshaping reference state. We apply the theory to explain the stress relaxation, the shape recovery after instant deformation, and the necking instability under a ramp deformation. We also examine the role of polydispersity in the mesh size of the network, which leads to a stretched exponential stress relaxation and a diffuse elastic-plastic transition under a ramp deformation. Although dynamic crosslinks are taken as the source of the transient network response, the model can be easily adjusted to incorporating other factors inducing fluidization, such as filament

show abstract

Mechanism of Calponin Stabilization of Cross-Linked Actin Networks

Cited by 24 publications

References 52 publications

Cnn3 regulates neural tube morphogenesis and neuronal stem cell properties

Cnn3 regulates neural tube morphogenesis and neuronal stem cell properties

Side-binding proteins modulate actin filament dynamics

Fluidization of Transient Filament Networks

Contact Info

Product

Resources

About