Topic
Cell Surface Extension
About: Cell Surface Extension is a research topic. Over the lifetime, 52 publications have been published within this topic receiving 4152 citations.
Papers published on a yearly basis
Papers
TL;DR: A new approach to produce genetically encoded photoactivatable derivatives of Rac1, a key GTPase regulating actin cytoskeletal dynamics in metazoan cells, which was shown to inhibit RhoA in mouse embryonic fibroblasts, with inhibition modulated at protrusions and ruffles.
Abstract: The precise spatio-temporal dynamics of protein activity are often critical in determining cell behaviour, yet for most proteins they remain poorly understood; it remains difficult to manipulate protein activity at precise times and places within living cells. Protein activity has been controlled by light, through protein derivatization with photocleavable moieties or using photoreactive small-molecule ligands. However, this requires use of toxic ultraviolet wavelengths, activation is irreversible, and/or cell loading is accomplished via disruption of the cell membrane (for example, through microinjection). Here we have developed a new approach to produce genetically encoded photoactivatable derivatives of Rac1, a key GTPase regulating actin cytoskeletal dynamics in metazoan cells. Rac1 mutants were fused to the photoreactive LOV (light oxygen voltage) domain from phototropin, sterically blocking Rac1 interactions until irradiation unwound a helix linking LOV to Rac1. Photoactivatable Rac1 (PA-Rac1) could be reversibly and repeatedly activated using 458- or 473-nm light to generate precisely localized cell protrusions and ruffling. Localized Rac activation or inactivation was sufficient to produce cell motility and control the direction of cell movement. Myosin was involved in Rac control of directionality but not in Rac-induced protrusion, whereas PAK was required for Rac-induced protrusion. PA-Rac1 was used to elucidate Rac regulation of RhoA in cell motility. Rac and Rho coordinate cytoskeletal behaviours with seconds and submicrometre precision. Their mutual regulation remains controversial, with data indicating that Rac inhibits and/or activates Rho. Rac was shown to inhibit RhoA in mouse embryonic fibroblasts, with inhibition modulated at protrusions and ruffles. A PA-Rac crystal structure and modelling revealed LOV-Rac interactions that will facilitate extension of this photoactivation approach to other proteins.
1,103 citations
TL;DR: It is demonstrated that mechanical force applied locally to C-cadherins on single Xenopus mesendoderm cells is sufficient to induce polarized cell protrusion and persistent migration typical of individual cells within a collectively migrating tissue.
385 citations
TL;DR: The data reveal that the type of protrusion formed by migrating cells can be dynamically controlled independently of overall cell morphology, suggesting that protrusion formation is an autonomous module in the regulatory network that controls the plasticity of cell migration.
Abstract: Protrusion formation is an essential step during cell migration. Cells migrating in three-dimensional environments and in vivo can form a wide variety of protrusion types, including actin polymerization-driven lamellipodia, and contractility-driven blebs. The ability to switch between different protrusions has been proposed to facilitate motility in complex environments and to promote cancer dissemination. However, plasticity in protrusion formation has so far mostly been investigated in the context of transitions between amoeboid and mesenchymal migration modes, which involve substantial changes in overall cell morphology. As a result, the minimal requirements of transitions between blebs and lamellipodia, as well as the time scales on which they occur, remain unknown. To address these questions, we investigated protrusion switching during cell migration at the single cell level. Using cells that can be induced to form either blebs or lamellipodia, we systematically assessed the mechanical requirements, as well as the dynamics, of switching between protrusion types. We demonstrate that shifting the balance between actin protrusivity and actomyosin contractility leads to immediate transitions between blebs and lamellipodia in migrating cells. Switching occurred without changes in global cell shape, polarity, or cell adhesion. Furthermore, rapid transitions between blebs and lamellipodia could also be triggered upon changes in substrate adhesion during migration on micropatterned surfaces. Together, our data reveal that the type of protrusion formed by migrating cells can be dynamically controlled independently of overall cell morphology, suggesting that protrusion formation is an autonomous module in the regulatory network that controls the plasticity of cell migration.
360 citations
TL;DR: A novel role for cell-cell adhesion in polarization is demonstrated, and have implications for wound healing and developmental patterning.
Abstract: Cell polarity is orchestrated by numerous extracellular cues, and guides events such as chemotaxis, mitosis and wound healing. In scrape-wound assays of cell monolayers, wound-edge cells orient their centrosomes towards the wound, a process that appears to depend on the formation of new cell–extracellular-matrix adhesions as cells spread into the wound. In direct contrast to scrape-wounded cells, isolated cells without cell-cell contacts failed to polarize, suggesting that asymmetry of cell-cell adhesions resulting from monolayer disruption might contribute to polarization. By using micropatterned substrates to engineer such asymmetries in kidney epithelial cells, we found that cell-cell contact induced displacement of the nucleus towards the contact, and also caused centrosomal reorientation and lamellipodial ruffling to the distal side of the nucleus. Upon release from micropatterned constraints, cells exhibited directed migration away from the cell-cell contact. Disrupting E-cadherin engagement randomized nuclear position and lamellipodial ruffling in patterned cultures, and abrogated scrape-wound-induced cell reorientation, but not migration rate. Polarity that was induced by cell-cell contact required an intact actin cytoskeleton and Cdc42 activity, but not RhoA or Rac signaling. Together, these findings demonstrate a novel role for cell-cell adhesion in polarization, and have implications for wound healing and developmental patterning.
259 citations
TL;DR: An assay based on high-resolution 3D multiple-particle tracking that allows us to probe local matrix remodeling during mesenchymal cell migration through a 3D matrix and simultaneously monitor protrusion dynamics indicates that Matrix remodeling spatially correlates with protrusive activity.
162 citations
Related Topics (5)
Performance Metrics
| Year | Papers |
|---|---|
| 2020 | 1 |
| 2018 | 2 |
| 2017 | 2 |
| 2016 | 4 |
| 2015 | 5 |
| 2014 | 1 |