2D and 3D Quantitative Analysis of Cell Motility and Cytoskeletal Dynamics

Cell migration is critical for regional dissemination and distal metastasis of cancer cells, which remain the major causes of poor prognosis and death in patients with colorectal cancer (CRC). Although cytoskeletal dynamics and cellular deformability contribute to the migration of cancer cells and metastasis, the mechanisms governing the migratory ability of cancer stem cells (CSCs), a nongenetic source of tumor heterogeneity, are unclear. Here, we expanded colorectal CSCs (CRCSCs) as colonospheres and showed that CRCSCs exhibited higher cell motility in transwell migration assays and 3D invasion assays and greater deformability in particle tracking microrheology than did their parental CRC cells. Mechanistically, in CRCSCs, microRNA-210-3p (miR-210) targeted stathmin1 (STMN1), which is known for inducing microtubule destabilization, to decrease cell elasticity in order to facilitate cell motility without affecting the epithelial–mesenchymal transition (EMT) status. Clinically, the miR-210-STMN1 axis was activated in CRC patients with liver metastasis and correlated with a worse clinical outcome. This study elucidates a miRNA-oriented mechanism regulating the deformability of CRCSCs beyond the EMT process.

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A quantitative analysis of wiring lengths in 2D and 3D VLSI implementation of 2D systolic arrays

1997 21st International Conference on Microelectronics. Proceedings ◽

10.1109/icmel.1997.632973 ◽

2002 ◽

Cited By ~ 1

Author(s):

A. Milenkovic ◽

V. Milutinovic

Keyword(s):

Quantitative Analysis ◽

Vlsi Implementation ◽

Systolic Arrays ◽

2D And 3D

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Arp2/3-Branched Actin Maintains an Active Pool of GTP-RhoA and Controls RhoA Abundance

Cells ◽

10.3390/cells8101264 ◽

2019 ◽

Vol 8 (10) ◽

pp. 1264

Author(s):

Yuxing Huang ◽

Xin Yi ◽

Chenlu Kang ◽

Congying Wu

Keyword(s):

Signal Transduction ◽

Cell Motility ◽

Small Gtpases ◽

Small Gtpase ◽

Protein Abundance ◽

Rhoa Activity ◽

Cytoskeletal Dynamics ◽

Active Pool ◽

Spatiotemporal Control

Small GTPases regulate cytoskeletal dynamics, cell motility, and division under precise spatiotemporal control. Different small GTPases exhibit cross talks to exert feedback response or to act in concert during signal transduction. However, whether and how specific cytoskeletal components’ feedback to upstream signaling factors remains largely elusive. Here, we report an intriguing finding that disruption of the Arp2/3-branched actin specifically reduces RhoA activity but upregulates its total protein abundance. We further dissect the mechanisms underlying these circumstances and identify the altered cortactin/p190RhoGAP interaction and weakened CCM2/Smurf1 binding to be involved in GTP-RhoA reduction and total RhoA increase, respectively. Moreover, we find that cytokinesis defects induced by Arp2/3 inhibition can be rescued by activating RhoA. Our study reveals an intricate feedback from the actin cytoskeleton to the small GTPase. Our work highlights the role of Arp2/3-branched actin in signal transduction aside from its function in serving as critical cytoskeletal components to maintain cell morphology and motility.

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Actin-depolymerizing Factor and Cofilin-1 Play Overlapping Roles in Promoting Rapid F-Actin Depolymerization in Mammalian Nonmuscle Cells

Molecular Biology of the Cell ◽

10.1091/mbc.e04-07-0555 ◽

2005 ◽

Vol 16 (2) ◽

pp. 649-664 ◽

Cited By ~ 240

Author(s):

Pirta Hotulainen ◽

Eija Paunola ◽

Maria K. Vartiainen ◽

Pekka Lappalainen

Keyword(s):

Cell Motility ◽

Actin Filament ◽

Actin Filaments ◽

Actin Dynamics ◽

Actin Binding ◽

Actin Depolymerizing Factor ◽

Cytoskeletal Dynamics ◽

Nonmuscle Cells ◽

In Cells

Actin-depolymerizing factor (ADF)/cofilins are small actin-binding proteins found in all eukaryotes. In vitro, ADF/cofilins promote actin dynamics by depolymerizing and severing actin filaments. However, whether ADF/cofilins contribute to actin dynamics in cells by disassembling “old” actin filaments or by promoting actin filament assembly through their severing activity is a matter of controversy. Analysis of mammalian ADF/cofilins is further complicated by the presence of multiple isoforms, which may contribute to actin dynamics by different mechanisms. We show that two isoforms, ADF and cofilin-1, are expressed in mouse NIH 3T3, B16F1, and Neuro 2A cells. Depleting cofilin-1 and/or ADF by siRNA leads to an accumulation of F-actin and to an increase in cell size. Cofilin-1 and ADF seem to play overlapping roles in cells, because the knockdown phenotype of either protein could be rescued by overexpression of the other one. Cofilin-1 and ADF knockdown cells also had defects in cell motility and cytokinesis, and these defects were most pronounced when both ADF and cofilin-1 were depleted. Fluorescence recovery after photobleaching analysis and studies with an actin monomer-sequestering drug, latrunculin-A, demonstrated that these phenotypes arose from diminished actin filament depolymerization rates. These data suggest that mammalian ADF and cofilin-1 promote cytoskeletal dynamics by depolymerizing actin filaments and that this activity is critical for several processes such as cytokinesis and cell motility.

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The lipid phosphatase-like protein PLPPR1 increases cell adhesion by modulating RhoA/Rac1 activity

10.1101/470914 ◽

2018 ◽

Author(s):

Chinyere Agbaegbu Iweka ◽

Sharada Tilve ◽

Caitlin Mencio ◽

Yasuhiro Katagiri ◽

Herbert M Geller

Keyword(s):

Cell Adhesion ◽

Cell Motility ◽

Lipid Phosphatase ◽

Rac1 Activity ◽

Cytoskeletal Dynamics ◽

Membrane Protrusions ◽

Exogenous Expression ◽

Pleiotropic Functions ◽

Related Proteins

ABSTRACTPhospholipid Phosphatase-Related Protein Type 1 (PLPPR1) is a member of a family of lipid phosphatase related proteins, integral membrane proteins characterized by six transmembrane domains. PLPPR1 is enriched in the brain and recent data indicate potential pleiotropic functions in several different contexts. An inherent ability of PLPPR1 is to induce membrane protrusions, and we have previously reported that members within this family may act in concert. However, the mechanism by which PLPPR1 produces these actions is not yet understood. Here, we report that exogenous expression of PLPPR1 reduces cell motility and increases cell adhesion to the ECM substrate by altering cytoskeletal dynamics and modulating RhoA and Rac1 activity through association with RhoGDI. This signaling also allows overexpression of PLPPR1 to overcome the inhibitory activity of CSPGs and LPA on neurites. Together, these results establish a novel signaling pathway for the PLPPR1 protein.SUMMARYPLPPR1 increases cell adhesion and decreases cell motility by modulating RhoA and Rac1 activation through its association with RhoGDI.

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