Betz, Timo

[["dc.bibliographiccitation.firstpage","1625"],["dc.bibliographiccitation.issue","6127"],["dc.bibliographiccitation.journal","Science"],["dc.bibliographiccitation.lastpage","1629"],["dc.bibliographiccitation.volume","339"],["dc.contributor.author","Lafaurie-Janvore, Julie"],["dc.contributor.author","Maiuri, Paolo"],["dc.contributor.author","Wang, Irène"],["dc.contributor.author","Pinot, Mathieu"],["dc.contributor.author","Manneville, Jean-Baptiste"],["dc.contributor.author","Betz, Timo"],["dc.contributor.author","Balland, Martial"],["dc.contributor.author","Piel, Matthieu"],["dc.date.accessioned","2020-11-23T10:41:55Z"],["dc.date.available","2020-11-23T10:41:55Z"],["dc.date.issued","2013-03-29"],["dc.description.abstract","The last step of cell division, cytokinesis, produces two daughter cells that remain connected by an intercellular bridge. This state often represents the longest stage of the division process. Severing the bridge (abscission) requires a well-described series of molecular events, but the trigger for abscission remains unknown. We found that pulling forces exerted by daughter cells on the intercellular bridge appear to regulate abscission. Counterintuitively, these forces prolonged connection, whereas a release of tension induced abscission. Tension release triggered the assembly of ESCRT-III (endosomal sorting complex required for transport-III), which was followed by membrane fission. This mechanism may allow daughter cells to remain connected until they have settled in their final locations, a process potentially important for tissue organization and morphogenesis."],["dc.identifier.doi","10.1126/science.1233866"],["dc.identifier.pmid","23539606"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/68970"],["dc.language.iso","en"],["dc.relation.eissn","1095-9203"],["dc.relation.issn","0036-8075"],["dc.title","ESCRT-III assembly and cytokinetic abscission are induced by tension release in the intercellular bridge"],["dc.type","journal_article"],["dc.type.internalPublication","no"],["dc.type.subtype","original_ja"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","5130"],["dc.bibliographiccitation.issue","12"],["dc.bibliographiccitation.journal","Biophysical Journal"],["dc.bibliographiccitation.lastpage","5138"],["dc.bibliographiccitation.volume","96"],["dc.contributor.author","Betz, Timo"],["dc.contributor.author","Koch, Daniel"],["dc.contributor.author","Lim, Daryl"],["dc.contributor.author","Käs, Josef A"],["dc.date.accessioned","2020-11-23T10:37:41Z"],["dc.date.available","2020-11-23T10:37:41Z"],["dc.date.issued","2009-06-17"],["dc.description.abstract","Neuronal growth is an extremely complex yet reliable process that is directed by a dynamic lamellipodial structure at the tip of every growing neurite, called the growth cone. Lamellipodial edge fluctuations are controlled by the interplay between actin polymerization pushing the edge forward and molecular motor driven retrograde actin flow retracting the actin network. The leading edge switches randomly between extension and retraction processes. We identify switching of \"on/off\" states in actin polymerization as the main determinant of lamellipodial advancement. Our analysis of motility statistics allows for a prediction of growth direction. This was used in simulations explaining the amazing signal detection capabilities of neuronal growth by the experimentally found biased stochastic processes. Our measurements show that the intensity of stochastic fluctuations depend on changes in the underlying active intracellular processes and we find a power law eta = a x(alpha) with exponent alpha = 2.63 +/- 0.12 between noise intensity eta and growth cone activity x, defined as the sum of protrusion and retraction velocity. Differences in the lamellipodial dynamics between primary neurons and a neuronal cell line further suggests that active processes tune the observed stochastic fluctuations. This hints at a possible role of noise intensity in determining signal detection sensitivity."],["dc.identifier.doi","10.1016/j.bpj.2009.03.045"],["dc.identifier.pmid","19527673"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/68920"],["dc.language.iso","en"],["dc.relation.eissn","1542-0086"],["dc.relation.issn","0006-3495"],["dc.title","Stochastic actin polymerization and steady retrograde flow determine growth cone advancement"],["dc.type","journal_article"],["dc.type.internalPublication","no"],["dc.type.subtype","original_ja"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","1667"],["dc.bibliographiccitation.issue","7"],["dc.bibliographiccitation.journal","Biophysical Journal"],["dc.bibliographiccitation.lastpage","1679"],["dc.bibliographiccitation.volume","114"],["dc.contributor.author","Ahmed, Wylie W"],["dc.contributor.author","Fodor, Étienne"],["dc.contributor.author","Almonacid, Maria"],["dc.contributor.author","Bussonnier, Matthias"],["dc.contributor.author","Verlhac, Marie-Hélène"],["dc.contributor.author","Gov, Nir"],["dc.contributor.author","Visco, Paolo"],["dc.contributor.author","van Wijland, Frédéric"],["dc.contributor.author","Betz, Timo"],["dc.date.accessioned","2020-11-23T10:38:42Z"],["dc.date.available","2020-11-23T10:38:42Z"],["dc.date.issued","2018"],["dc.description.abstract","Active diffusion of intracellular components is emerging as an important process in cell biology. This process is mediated by complex assemblies of molecular motors and cytoskeletal filaments that drive force generation in the cytoplasm and facilitate enhanced motion. The kinetics of molecular motors have been precisely characterized in vitro by single molecule approaches, but their in vivo behavior remains elusive. Here, we study the active diffusion of vesicles in mouse oocytes, where this process plays a key role in nuclear positioning during development, and combine an experimental and theoretical framework to extract molecular-scale force kinetics (force, power stroke, and velocity) of the in vivo active process. Assuming a single dominant process, we find that the nonequilibrium activity induces rapid kicks of duration τ ∼ 300 μs resulting in an average force of F ∼ 0.4 pN on vesicles in in vivo oocytes, remarkably similar to the kinetics of in vitro myosin-V. Our results reveal that measuring in vivo active fluctuations allows extraction of the molecular-scale activity in agreement with single-molecule studies and demonstrates a mesoscopic framework to access force kinetics."],["dc.identifier.arxiv","1510.08299v3"],["dc.identifier.doi","10.1016/j.bpj.2018.02.009"],["dc.identifier.pmid","29642036"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/68931"],["dc.language.iso","en"],["dc.relation.eissn","1542-0086"],["dc.relation.issn","0006-3495"],["dc.title","Active Mechanics Reveal Molecular-Scale Force Kinetics in Living Oocytes"],["dc.type","journal_article"],["dc.type.internalPublication","no"],["dc.type.subtype","original_ja"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","1019"],["dc.bibliographiccitation.issue","9"],["dc.bibliographiccitation.journal","Nature Materials"],["dc.bibliographiccitation.lastpage","1025"],["dc.bibliographiccitation.volume","19"],["dc.contributor.author","Rheinlaender, Johannes"],["dc.contributor.author","Dimitracopoulos, Andrea"],["dc.contributor.author","Wallmeyer, Bernhard"],["dc.contributor.author","Kronenberg, Nils M."],["dc.contributor.author","Chalut, Kevin J."],["dc.contributor.author","Gather, Malte C."],["dc.contributor.author","Betz, Timo"],["dc.contributor.author","Charras, Guillaume"],["dc.contributor.author","Franze, Kristian"],["dc.date.accessioned","2020-11-23T10:39:52Z"],["dc.date.available","2020-11-23T10:39:52Z"],["dc.date.issued","2020-09"],["dc.description.abstract","Cortical stiffness is an important cellular property that changes during migration, adhesion and growth. Previous atomic force microscopy (AFM) indentation measurements of cells cultured on deformable substrates have suggested that cells adapt their stiffness to that of their surroundings. Here we show that the force applied by AFM to a cell results in a significant deformation of the underlying substrate if this substrate is softer than the cell. This 'soft substrate effect' leads to an underestimation of a cell's elastic modulus when analysing data using a standard Hertz model, as confirmed by finite element modelling and AFM measurements of calibrated polyacrylamide beads, microglial cells and fibroblasts. To account for this substrate deformation, we developed a 'composite cell-substrate model'. Correcting for the substrate indentation revealed that cortical cell stiffness is largely independent of substrate mechanics, which has major implications for our interpretation of many physiological and pathological processes."],["dc.identifier.doi","10.1038/s41563-020-0684-x"],["dc.identifier.pmid","32451510"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/68945"],["dc.language.iso","en"],["dc.relation.issn","1476-1122"],["dc.title","Cortical cell stiffness is independent of substrate mechanics"],["dc.type","journal_article"],["dc.type.internalPublication","unknown"],["dc.type.subtype","original_ja"],["dspace.entity.type","Publication"]]

[["dc.contributor.author","Nguyen, Alfred"],["dc.contributor.author","Brandt, Matthias"],["dc.contributor.author","Betz, Timo"],["dc.date.accessioned","2020-11-23T10:41:30Z"],["dc.date.available","2020-11-23T10:41:30Z"],["dc.date.issued","2020"],["dc.identifier.doi","10.1101/2020.07.02.185330"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/68965"],["dc.title","Microchip based microrheology via Acoustic Force Spectroscopy shows that endothelial cell mechanics follows a fractional viscoelastic model"],["dc.type","preprint"],["dc.type.internalPublication","unknown"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","198a"],["dc.bibliographiccitation.issue","3"],["dc.bibliographiccitation.journal","Biophysical Journal"],["dc.bibliographiccitation.volume","110"],["dc.contributor.author","Ahmed, Wylie"],["dc.contributor.author","Fodor, Etienne"],["dc.contributor.author","Almonacid, Maria"],["dc.contributor.author","Bussonnier, Matthias"],["dc.contributor.author","Verlhac, Marie-Helene"],["dc.contributor.author","Gov, Nir"],["dc.contributor.author","Visco, Paolo"],["dc.contributor.author","Wijland, Frederic van"],["dc.contributor.author","Betz, Timo"],["dc.date.accessioned","2020-11-23T10:38:22Z"],["dc.date.available","2020-11-23T10:38:22Z"],["dc.date.issued","2016"],["dc.identifier.doi","10.1016/j.bpj.2015.11.1104"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/68927"],["dc.relation.issn","0006-3495"],["dc.title","Active Mechanics in Living Oocytes Reveal Molecular-Scale Force Kinetics"],["dc.type","journal_article"],["dc.type.internalPublication","no"],["dc.type.subtype","original_ja"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","e1295"],["dc.bibliographiccitation.issue","Suppl. 1"],["dc.bibliographiccitation.journal","Ultrasonics"],["dc.bibliographiccitation.lastpage","e1300"],["dc.bibliographiccitation.volume","44"],["dc.contributor.author","Kamanyi, Albert"],["dc.contributor.author","Ngwa, Wilfred"],["dc.contributor.author","Betz, Timo"],["dc.contributor.author","Wannemacher, Reinhold"],["dc.contributor.author","Grill, Wolfgang"],["dc.date.accessioned","2020-11-23T10:39:14Z"],["dc.date.available","2020-11-23T10:39:14Z"],["dc.date.issued","2006-12-22"],["dc.description.abstract","Combined phase-sensitive acoustic microscopy (PSAM) at 1.2 GHz and confocal laser scanning microscopy (CLSM) in reflection and fluorescence has been implemented and applied to polymer blend films and fluorescently labeled fibroblasts and neuronal cells in order to explore the prospects and the various contrast mechanisms of this powerful technique. Topographic contrast is available for appropriate samples from CLSM in reflection and, with significantly higher precision, from the acoustic phase images. Material contrast can be gained from acoustic amplitude V(z) graphs. In the case of the biological cells investigated, the optical and acoustic images are very different and exhibit different features of the samples."],["dc.identifier.doi","10.1016/j.ultras.2006.05.030"],["dc.identifier.pmid","16806359"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/68937"],["dc.language.iso","en"],["dc.relation.eissn","1874-9968"],["dc.relation.issn","0041-624X"],["dc.title","Combined phase-sensitive acoustic microscopy and confocal laser scanning microscopy"],["dc.type","journal_article"],["dc.type.internalPublication","no"],["dc.type.subtype","original_ja"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","1131"],["dc.bibliographiccitation.issue","5-7"],["dc.bibliographiccitation.journal","Materials Science & Engineering. C, Biomimetic and Supramolecular Systems"],["dc.bibliographiccitation.lastpage","1135"],["dc.bibliographiccitation.volume","26"],["dc.contributor.author","Rudolph, T."],["dc.contributor.author","Zimmer, K."],["dc.contributor.author","Betz, T."],["dc.date.accessioned","2020-11-23T10:39:09Z"],["dc.date.available","2020-11-23T10:39:09Z"],["dc.date.issued","2006"],["dc.identifier.doi","10.1016/j.msec.2005.09.072"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/68936"],["dc.relation.issn","0928-4931"],["dc.title","Microstructuring of UV-transparent functionalised films on glass by excimer laser irradiation"],["dc.type","journal_article"],["dc.type.internalPublication","no"],["dc.type.subtype","original_ja"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","1492"],["dc.bibliographiccitation.issue","13"],["dc.bibliographiccitation.journal","Current Biology"],["dc.bibliographiccitation.lastpage","1499"],["dc.bibliographiccitation.volume","24"],["dc.contributor.author","Elkhatib, Nadia"],["dc.contributor.author","Neu, Matthew B."],["dc.contributor.author","Zensen, Carla"],["dc.contributor.author","Schmoller, Kurt M."],["dc.contributor.author","Louvard, Daniel"],["dc.contributor.author","Bausch, Andreas R."],["dc.contributor.author","Betz, Timo"],["dc.contributor.author","Vignjevic, Danijela Matic"],["dc.date.accessioned","2020-11-23T10:38:57Z"],["dc.date.available","2020-11-23T10:38:57Z"],["dc.date.issued","2014-07-07"],["dc.description.abstract","Migrating cells nucleate focal adhesions (FAs) at the cell front and disassemble them at the rear to allow cell translocation. FAs are made of a multiprotein complex, the adhesome, which connects integrins to stress fibers made of mixed-polarity actin filaments [1-5]. Myosin II-driven contraction of stress fibers generates tensile forces that promote adhesion growth [6-9]. However, tension must be tightly controlled, because if released, FAs disassemble [3, 10-12]. Conversely, excess tension can cause abrupt cell detachment resulting in the loss of a major part of the adhesion [9, 12]. Thus, both adhesion growth and disassembly depend on tensile forces generated by stress fiber contraction, but how this contractility is regulated remains unclear. Here, we show that the actin-bundling protein fascin crosslinks the actin filaments into parallel bundles at the stress fibers' termini. Fascin prevents myosin II entry at this region and inhibits its activity in vitro. In fascin-depleted cells, polymerization of actin filaments at the stress fiber termini is slower, the actin cytoskeleton is reorganized into thicker stress fibers with a higher number of myosin II molecules, FAs are larger and less dynamic, and consequently, traction forces that cells exert on their substrate are larger. We also show that fascin dissociation from stress fibers is required to allow their severing by cofilin, leading to efficient disassembly of FAs."],["dc.identifier.doi","10.1016/j.cub.2014.05.023"],["dc.identifier.pmid","24930964"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/68934"],["dc.language.iso","en"],["dc.relation.eissn","1879-0445"],["dc.relation.issn","0960-9822"],["dc.title","Fascin plays a role in stress fiber organization and focal adhesion disassembly"],["dc.type","journal_article"],["dc.type.internalPublication","no"],["dc.type.subtype","original_ja"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","3083"],["dc.bibliographiccitation.issue","11"],["dc.bibliographiccitation.journal","Biochimica et Biophysica Acta"],["dc.bibliographiccitation.lastpage","3094"],["dc.bibliographiccitation.volume","1853"],["dc.contributor.author","Ahmed, Wylie W"],["dc.contributor.author","Fodor, Étienne"],["dc.contributor.author","Betz, Timo"],["dc.date.accessioned","2020-11-23T10:37:36Z"],["dc.date.available","2020-11-23T10:37:36Z"],["dc.date.issued","2015-11"],["dc.description.abstract","Living cells are active mechanical systems that are able to generate forces. Their structure and shape are primarily determined by biopolymer filaments and molecular motors that form the cytoskeleton. Active force generation requires constant consumption of energy to maintain the nonequilibrium activity to drive organization and transport processes necessary for their function. To understand this activity it is necessary to develop new approaches to probe the underlying physical processes. Active cell mechanics incorporates active molecular-scale force generation into the traditional framework of mechanics of materials. This review highlights recent experimental and theoretical developments towards understanding active cell mechanics. We focus primarily on intracellular mechanical measurements and theoretical advances utilizing the Langevin framework. These developing approaches allow a quantitative understanding of nonequilibrium mechanical activity in living cells. This article is part of a Special Issue entitled: Mechanobiology."],["dc.identifier.doi","10.1016/j.bbamcr.2015.05.022"],["dc.identifier.pmid","26025677"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/68919"],["dc.language.iso","en"],["dc.relation.issn","0006-3002"],["dc.title","Active cell mechanics: Measurement and theory"],["dc.type","journal_article"],["dc.type.internalPublication","no"],["dc.type.subtype","original_ja"],["dspace.entity.type","Publication"]]