The Advanced ESF-FEBS workshop on
Integrated Approaches in Cytoskeleton Research
27-31 August 2005
Luxembourg-City, Luxembourg

Organisers:

Evelyne Friederich, Centre de Recherche Public-Santé, Luxembourg
André Steinmetz, Centre de Recherche Public-Santé, Luxembourg

Draft Report

Introduction

Composed of more than thousands of proteins, the cytoskeleton is the supporting framework for cells interconnecting the nuclear matrix to the plasma membrane. Present in every animal or plant cell, this highly dynamic structure contributes to many cellular functions, including locomotion, cell division, membrane traffic, signalling and modelling of the chromatin. Playing an essential role in the compartmentalisation of the eucaryotic cell cytoplasm, the cytoskeleton controls cell and tissue plasticity during biological processes like development, wound repair or activation of the immune response. It is therefore not surprising that mutations in genes encoding cytoskeletal proteins cause a large panel of diseases including neurological disorders, immune deficiencies, skin disorders, deafness or muscle dysfunction. In addition, alterations of the cytoskeleton contribute to loss of cell-cell or cell-matrix adhesions and to uncontrolled movement of tumour cells. Cytoskeleton research, a fast moving area, is therefore far-reaching and not reserved to specialists in this field, but also of high interest for other scientists. Progress in cytoskeleton research in the European area can only be achieved through a multidisciplinary approach.

Summary

From the 27 - 31 August, over 150 participants from 12 European countries, Israel, Russia, the USA, Australia and Japan came together in the Cultural Centre of Neumünster Abbey located in the historical heart of Luxembourg-City, to exchange information and ideas in the cytoskeleton research field. Reflected by a large number of registrations, the attraction of the topics of this workshop to scientists highlighted the importance of cytoskeleton research in the European Research Area.

This international workshop was a joined affair of three scientific organisations that financed the event : the European Science Foundation (ESF, http://www.esf.org), the Federation of European Biochemical Societies (FEBS, http://www.febs.unibe.ch) and the National Research Fund of Luxembourg (FNR, http://www.fnr.lu), and was organised with the help of the European Cytoskeleton Forum, within a series of international meetings initiated in 1981 (please see scientific committee, http://www.weizmann.ac.il/eurocyto/home.html). The workshop was also the first scientific event to be held in Luxembourg in the context of the participation of the National Research Fund to the Functional Genomics Programme of the European Science Foundation (http://www.functionalgenomics.org.uk). A total of 49 YTFs (FEBS : 22; ESF : 16, FNR : 11) covering registration fee, living expenses and travel costs were awarded to students and young scientists from 10 European countries, Russia and Israel.

Aiming at stimulating communication and scientific exchange, the workshop brought together young scientists and their experienced colleagues. From the opening lecture of the workshop that was given by Eric KARSENTI, coordinator of the cell biology and biophysics program at the EMBL Heidelberg, to the end of the meeting on Wednesday 31st, there were 22 invited speakers coming from Europe (18), Israel (1), the USA (2), and Japan (1) who spoke at the 10 sessions. Young authors of the most attractive poster abstracts were selected to give 21 oral presentations alongside the senior scientists who introduced the session topics. Established scientists of the cytoskeleton research area who also contributed to the organisation of the workshop chaired the sessions.

Sessions covered hot spot areas of cytoskeleton research like cytoskeleton dynamics, diseases and biophysics, and aimed at breaking boundaries between subjects and scientists approaching the cytoskeleton from different angles of view. A particular emphasis was given to integrative, interdisciplinary aspects of cytoskeleton research bringing together molecular cell biologists, biochemists, physicists and medical researchers.

Scientific Content

Opening lecture Taking as an example the assembly of the mitotic spindle, Eric KARSENTI (EMBL, Heidelberg) gave an impressive talk on how intracellular regulatory gradients together with the collective behaviour of cell components can contribute to cell and tissue morphogenesis. Participants lively discussed his innovative approach that is based on cell imaging, biochemical data, mathematical and biophysical modelling.

Session 1 Structure and Assembly of Cytoskeleton Complexes
Chair: Joël VANDERKERCKHOVE, Belgium Toshio YANAGIDA (University of Osaka, Japan) introduced advanced intra-molecular FRET (Fluorescence Energy Transfer) methodologies and showed, based on this trechnology, that actin filaments undergo spontaneous, cyclic transitions from an active to an inactive state that might control the interaction with myosin by exposing hydrophobic faces. Ueli AEBI (M.E. Müller-Institut, Biozentrum, Basel, Switzerland) addressed the challenging question of how to solve the structure of the fibrous intermediate filaments. He proposed to reconstitute intermediate filament structure from information gained from the analysis the atomic structure of IF fragments.
Short presentations: Heidi ROMMELAERE, (University of Gent, VIB) addressed the structure-function relationship of alpha actin mutants occurring in patients with myopathia, in cell-based and novel, in vitro translation-coupled biochemical assays. Bernard WEHRLE-HALLER (Medical Center University of Geneva, Switzerland) reported on the assembly mechanism of focal adhesion protein complexes and showed that the cytoskeleton linker protein talin induced integrin- clustering, independent on dimer formation and detectable actin interaction.

Session 2 Molecular Motors
Chair: André STEINMETZ, Luxemburg Manfred SCHLIWA (University of Munich, Germany) gave an overview on motor proteins mechanics and addressed evolutionary aspects of kinesins during his talk. He reported how subtle structural differences in the neck domain of fungal kinesins can affect the motor activity of these proteins, the velocity of fungal kinesin1 being 4 fold faster than that of the animal homologue. Based on a large panel of assays in which kinesin1 mutants were analysed, he proposed a model where complex interactions of the coiled-coiled neck domain and the more flexible hinge region regulate motor activity and dimerisation. Mark MOOSEKER (Yale University, USA) dissected the cascade of molecular events leading, after the genetic inactivation of non-conventional myosin 1A, to structural and functional perturbations of the intestinal brush border, a complex plasma-membrane-actin cytoskeleton specialisation. Brush border microvilli of null mice were less stress-resistant, exhibiting increased sensitivity to Ca2+ and instability of membrane micro-domains, highlighting the integrative role of non-conventional myosins in the organisation of the cortical membrane actin cytoskeleton.
Short presentations: Kristopher CLARK (University of Nijmegen, The Netherlands) presented data on the role TRPM7, an integral membrane protein composed of a kinase domain linked to a cation channel in myosin II contractibility-dependent cell-matrix-adhesion. Sébastien SCHAUB (University of Lausanne, Switzerland) used fish keratinocytes as a cell model to investigate coordination of actin and myosin II movement in migrating cells by computer-assisted quantitative live-cell imaging.

Session 3 Cytoskeletal Dynamics I
Chair: Victor SMALL, Austria Marie France CARLIER (LEBS, CNRS, Gif/Yvette, France) opened this session by introducing control mechanisms of actin dynamics and actin-based movement in cells. She presented novel data on twinfilin, a protein structurally similar to the actin-depolymerising proteins cofilin/ADF, and showed that this protein has capping activity in vitro and can promote actin-based movement in a bio-mimetic assay. The potential physiological relevance of ADP-actin filaments capping by twinfilin was discussed. Alexander BERSHADSKY (The Weizmann Institute, Rehovot, Israel) addressed biophysical aspects of formin-dependent actin nucleation and proposed a novel model for processive actin capping by formins in which pulling forces would highly increase forming-dependent actin polymerisation. During the second part of his talk, he presented data on the functional links between myosin-based contractibility, actin polymerisation and microtubule dynamics in cell motility.
Short presentations: Heather LONG (University of Durham, UK) presented data on the intracellular distribution of the cytoskeleton linker plakin. Alphée MICHELOT (Labo. Physio. Cellulaire Végétale, Grenoble, France) reported on the nucleation and actin organisation activities of plant formin and their implications in pollen tube formation in plants. He reported a role for the formin FH1 domain in the modulation of actin dynamics by the formin FH2 domain.

Session 4 Cytoskeletal Dynamics II
Chair: Christophe AMPE, Belgium Tijs KETELAAR (Wageningen University, The Netherlands) introduced root hair cells as a plant cell model to study cytoskeleton dynamics and cell expansion. He reported and evaluated role of the microtubule and actin cytoskeletal systems in exocytosis and determination of directionality of cell growth.
Short presentations: Céline REVENU (Curie Institute, Paris, France) presented data on the dual role of villin, an actin filament bundling and severing protein in cell morphogenesis and migration. Gemma BELLETT (University of East Anglia, Norwich, UK) addressed the assembly mechanism of the non-radial microtubules in polarized epithelial cells. Based on nocodazole microtubule re-growth experiments and immuno-localisation studies, she proposed a mechanism in which microtubule plus ends capture at cell junctions constitutes a intermediate step in the generation of an apico-basal array of microtubules that is dependent on actin cytoskeleton. Roser PINYOL (Leibnitz-Institute for Neurobiology, Magdeburg, Germany) reported results on the activation mechanism of N-WASP by the SH3 domain of Abp1 and discussed the potential role of Arp2/3 complex mediated actin polymerization during endocytosis.

Session 5 Special session on Live Cell Imaging and Emerging Technologies
Chair: Mario GIMONA, Italy Klemens ROTTNER (GFB, Braunschweig, Germany) presented data on the functional dissimilarities of the WASP and WAVE-mediated actin nucleation. He dissected the recruitment of the actin-polymerisation machinery during clathrin-coated pit internalisation in living cells using two-colour total internal reflection microscopy and discussed the role of N-WASP-promoted actin polmerisation in endocytosis. Using live cell imaging microscopy approaches (FRAP, FLIP), Rainer PEPPERKOK (EMBL, Heidelberg), reported the interaction of the Sec23, a protein of the COPII complex, with p150glued of the dynactin microtubule motor complex. Based on biological and biochemical data as well on mathematical modelling, he discussed how this interaction might contribute to the regulation of cargo export from the endoplasmic reticulum.
Short presentations: Using multiple-colour live-cell imaging. Pirta HOTULAINEN (University of Helsinki, Finland) reported two distinct assembly mechanisms of actin cables in mammalian cells, one involving actin polymerisation and the other a-actinin and myosin II. Suha NAFFAR-ABU-AMARA (The Weizmann Institute, Rehovot, Israel) reported a novel high-throughput screening assay for invasion-associated genes, combining automated, computer-assisted analysis of the motile behaviour of non-invasive cells after their infection with a cDNA library established from invasive cells. Julien COLOMBELLI (EMBL, Heidelberg) presented a powerful microscopy-based approach based on a subnanosecond pulsed UV laser for localised severing of microtubules or actin filaments and subsequent measurement of their shrinkage rate in the context of living cells.

Session 6 Nuclear Function of Cytoskeletal Proteins
Chair: Christine CHAPONNIER (Switzerland) Richard TREISMAN (Cancer Research UK London Research Institute, London, UK) introduced how rho-GTPase control gene transcription, by regulated actin dynamics and G-actin content. He reported that rho-induced decrease of G-actin content controls the nuclear localisation of MAL, a co-activator of the SRF (Serum Response Factor) the nuclear import of which is inhibited when bound to G-actin. Roland FOISNER (Vienna Biocenter, Vienna, Austria) gave an introductory overview about the nuclear cytoskeleton and more specifically on nuclear lamina proteins. He addressed how mutations in these proteins can cause a large variety of human diseases, the laminopathies that affect various tissues. He discussed the potential physio-pathological functions and of the non-membrane bound LAP2a, a lamin A associated protein with a dual function in cell cycle-dependent chromatin organisation and cell plasticity.
Short communications: Avri BEN-ZE'EV (The Weizmann Institute, Rehovot, Israel) gave an introduction on cell-cell adhesion associated beta-catenin signalling to the nucleus and the implication of this signalling pathway in progression of cancer cells to a metastatic state. He reported and discussed findings on how cleavage of the extracellular domain of the neuronal cell adhesion molecule L1, a target gene of beta-catenin, by metalloproteases might contribute to the regulation cell motility and invasion of cancer cells. Jens GRUBER (Max Planck-Institute for Biophysical Chemistry, Göttingen, Germany) presented data on proteolytical processing of prelaminA by the endoprotease FACE1, and the relationship of prelaminA accumulation in the cells of patients with the Hutchinson - Gilford progeria syndrome.

Session 7 Model Organisms
Chair: Roger KARLSSON (Sweden) Angelika NOEGEL (University of Cologne, Germany) introduced the slime mold Dictyostelium discoideum as a powerful model organism to study cell migration, chemotaxis, phagocytosis. She presented the recently accomplished D. discoideum genome project and potential functional genomics applications. She reported data on the role of CAP (Cyclase Associated Protein) a protein linking the endomembrane system to the actin cytoskeleton, as an example of how to study cytoskeletal protein in D. discoideum. Jürgen WEHLAND (GFB, Braunschweig, Germany) gave first an overview on the different cytoskeleton-based strategies that microbial pathogens developed to survive and spread in the host organism and to avoid its immune system. How these pathogens can be used as model organisms to study cytoskeleton systems was discussed. Second, he reported a functional study of tyrosine-ligation, a post-translational modification of the C-terminus of alpha tubulin, in a mouse model and showed the implication of this enzyme in the differentiation process of neurons and the establishment of neuronal networks during brain development.
Short communications: Raissa ELUERE (IBSM-CNRS, France) introduced the budding yeast Saccaromyces cerevesiae as a genetic model system to study cytoskeleton-dependent cell processes and reported data on the role of Bud3 in the formation of the septin network during cytokinesis. Sawako YAMASHIRO reported data on the regulation of actin dynamics in myofibrils by the balance of actin-depolymerising and stabilising protein activities in the worm Caenorhabditis elegans.

Session 8 Integrated Cytoskeletal Circuits
Chair: Daniel LOUVARD (France) Mary BECKERLE (University of Utah, Huntsman Institute, Salt Lake City, USA) introduced LIM-proteins as molecular scaffolds linking the cytoskeleton to cell signalling and gene regulation, and reported novel findings on the mechano-sensor function of zyxin, the founding member of the LIM-protein family. The mechanisms by which zyxin might participate in the reinforcement of actin cables after application of mechanical stress to cells was discussed. Guy TANENTZAPF (Gurdon Institute, Cambridge, UK) introduced integrin adhesion receptors and approached the role of talin, a multiple-domain cytoskeleton- integrin protein, during embryonic development in the genetic Drosophila fly model. By genetic and mutational analyses, he demonstrated the unique role of talin in linking the actin cytoskeleton to integrins and the functional redundancy of binding sites that might contribute to the plasticity of membrane-cytoskeleton interactions. Monique ARPIN (Curie Institute, Paris, FRANCE) introduced ezrin, an ERM membrane-cytoskeleton linker family member involved in cell motility, proliferation and transformation. She reported novel data on the regulation of ezrin by PIP2 and by a feedback loop mechanism of src-mediated ezrin tyrosine phosphorylation. These data were integrated into models for ezrin function in cell motility and morphogenesis. Giorgio SCITA (IFOM, Milano, Italy) reported on the role of Abi1 and Eps8, two signalling molecules in the control of actin dynamics and spatial organisation of the actin cytoskeleton in a cellular context. How these proteins may participate in distinct cellular function through their localisation to various supra-molecular protein complexes was discussed.
Short communications: Chen LUXENBOURG (The Weizmann Institute, Rehovot, Israel) reported on the role of the role of the src-cortactin pathway, linking signaling to the actin cytoskeleton to podosome dynamics and osteoclast polarization, processes involved in the remodeling of the extracellular matrix. Jean Pierre WIPFF (Swiss Institute of Technology, Lausanne, Switzerland) addressed by combined biophysical and bio-chemical approaches the relationship between TGF-ß activation and mechanical stress. He discussed how intracellular response to stress and stress-induced compliance of the extracellular matrix might contribute to this process.

Session 9 Biophysics of the Cytoskeleton
Chair: Alexander BERSHADSKY (the Weizmann Institute, Rehovot, Israel, replacing Benny GEIGER) Cécile SYKES (Curie Institute, Paris, France) gave a comprehensive introduction to the history of biophysics and examples of how biophysical approaches might contribute to the understanding of biological system. She described a bio-mimetic acellular system for actin-based cell motility that is based on the Listeria bacteria model. She showed how actin polymerisation and asymmetric breakage of surface-associated actin gels might generate force required for biological processes like cell migration or cytokinesis. Marileen DOGTEROM (AMOLF, Amsterdam, The Netherlands) addressed the physical properties of microtubules and described experimental assays to measure and quantify force generated by microtubule polymerisation-motor systems.
Short communications: Based on biophysical approaches, Laurent KREPLAK (Biozentrum, Basel, Switzerland) addressed the issue of how intermediate filaments might act as integrators of mechanical of the cellular space. Using atomic force microscopy, he demonstrated their flexibility and capacity to respond to mechanical stretching, a property that may be relevant during muscle contraction. Jan W. VOS (AMOLF, Amsterdam, The Netherlands) reported modelling data on the microtubule organisation in interphase Tobacco BY-2 cells.

Session 10 Cytoskeleton and Disease
Chair: Olli CARPEN (Finland) In continuation with the session on nuclear aspects of the cytoskeleton Frans RAMAEKERS (University Maastricht, The Netherlands) reported how mutations in lamin A/C genes that encode proteins of the karyoskeleton can cause diseases like cardio-distrophy by altering the response of cells to mechanical stress. Complementary approaches were used to analyse the consequences of mechanical compression on the structural integrity of fibroblasts lacking lamin A/C, revealing a general cell weakening and a disorganisation of the three cytoplasmic cytoskeleton systems.
John CONDEELIS (Albert Einstein College of Medecine, New York, USA) reported how complementary biochemical, transcriptomic and intra-vital imaging methodologies can be integrated to address a complex biological process like tumour cell invasion. Combining these approaches, he investigated the role of EGF-signalling to the cytoskeleton during tumour cell invasion and dissected this regulatory pathway by gene expression profiling. He demonstrated that EGF-signalling through LIM-kinase controls the dual actin depolmerisation/polymerisation function of cofilin and the directionality of cell migration.
Short communication: Johan DE ROOIJ (The Netherlands Cancer Institute, Amsterdam, The Netherlands) reported that acto-myosin contraction might induce epithelial cell scattering and loss of cell-cell contcats, a key event of tumor cell invasion, independent on E-cadherin down-regulation.

Poster sessions Three poster sessions (please see abstracts) were held in the evening or afternoon at the Alvisse Park Hotel where all the participants were accommodated, stimulating animated discussions around the 103 posters that were exposed and accessible throughout the meeting. Three scientists (Christine Chaponnier, Mario Gimona, André Steinmetz) of the organisation committee selected the posters evaluation committee. The two best-presented posters were awarded prices sponsored by FEBS (Marjo DE GRAAUW : Phosphotyrosine Proteomics of the Epithelial-Mesenchymal Transition, Leiden University, The Netherlands; David MOSS : Microtubule Array Rearrangement during Epithelial Cell Apoptosis, School of Medical Sciences, Bristol, UK). Social interactions were further favoured through an excursion to the Moselle, the wine area of Luxembourg. Poster prices were awarded before the gala dinner that took place in a wine cellar in Wormeldange.


Conclusions and future directions

The workshop aimed at serving as a platform for discussion and exchange of novel developments in cytoskeleton research. Because of the far-reaching implications of cytoskeleton biology in many research areas and the societal importance of cytoskeleton-associated diseases, stimulating the development of innovative, interdisciplinary approaches is needed to unravel the biological and biophysical properties of the cytoskeleton systems. In line, breaking boundaries in the cytoskeleton research field was one of the objectives of the workshop. According the participants' feedback on the workshop, this goal was fully reached. For example, to stimulate comparative approaches dedicated to the analysis of cytoskeleton systems, presentations on plant cytoskeleton were integrated into sessions addressing common properties of cytoskeleton systems. During the discussions following the presentations it was also concluded that the three major cytoskeleton networks, actin filaments, microtubules and intermediate filaments are intimately linked and should be considered as a structural and functional entity. Single molecule and cell imaging technologies combined to biophysical and mathematical modelling are needed to advance in understanding complex cytoskeleton-based biological process like cell migration, morphogenesis, signalling or intracellular traffic. Addressing the issue of how cytoskeleton systems integrate cytoplasmic events and link them to nuclear processes like transcription was identified as an emerging topic. In this regard, several talks highlighted the importance of the actin cytoskeleton as a biochemical and mechano-senor involved in the regulation of cell and tissue plasticity. In addition, unravelling the function of the large repertoire of cytoskeleton proteins will require further development of global approaches like RNAi-based high throughput phenotypic screening or microarray-based expression profiling in cells or model organisms. Attendance at the workshop revealed that a broad scientific community is interested in the role of cytoskeleton systems in disease, yet is not necessary specialised in the cytoskeleton research area. Thus, it will be important to develop European networks brining together cytoskeleton specialists, clinicians, geneticists and physicists aiming at integrating knowledge on cytoskeleton aspects of complex-trait or genetic diseases including cancer, myopathies or laminopathies.

Programme
Saturday 27 August
14:00-16:00 Arrival and registration (Alvisse Parc Hotel)
16:15 Bus transportation to venue
17:00-17:15 Welcome: Raymond BAUSCH, National Research Fund, and Robert KANZ, Public Research Center for Health
17:15-18:15 Opening Lecture: Eric KARSENTI Self-Organization Principles and Mitotic Spindle Morphogenesis
19.00-22:15 Dinner followed by informal get-together
22:30 Bus transportation to Hotel

Sunday 28 August
8:50-10:30 Session 1 STRUCTURE AND ASSEMBLY OF CYTOSKELETON COMPLEXES
Chair: Joël Vandekerckhove
8:50-9:00 Evelyne FRIEDERICH Welcome and opening remarks
9:00-9.30 Toshio YANAGIDA Dynamic Polymorphism of Actin Molecules in the Filament
9:30-10:00 Ueli AEBI
Can We Ever Determine the Structure of Intermediate Filaments at Atomic Detail?
10:00-10:15 Heidi ROMMELAERE Characterization of Alpha-Skeletal Muscle Actin Mutants Causing Nemaline Myopathy: Expression in Cultured Skeletal Muscle Cells Causes Various Aberrant Phenotypes
10:15-10:30 Bernhard WEHRLE-HALLER The Mechanism and Dynamics of Avb3 Integrin Clustering in Living Cells
10:30-11:00 COFFEE BREAK
11:00-12:40 Session 2 MOLECULAR MOTORS
Chair: André Steinmetz
11:00-11:30 Manfred SCHLIWA Molecular Mechanics of the Kinesin Motor
11:30-12:00 Mark MOOSEKER Defining the In Vivo Functions for Enterocyte Class I Myosin, Myosin-Ia (Myo1a)
12:00-12:15 Kristopher CLARK TRPM7, a Novel Regulator of Actomyosin Contractility and Cell Adhesion
12:15-12:30 Sébastien SCHAUB Mapping the Movement and Assembly of Filamentous Actin and Myosin II in Migrating Fish Epidermal Keratocytes
12:40-14:30 LUNCH
14:30-16:30 Session 3
CYTOSKELETAL DYNAMICS 1
Chair: Victor Small
14:30-15:00 Marie-France CARLIER
Control Mechanisms of Actin Polymerisation
15:00-15:30 Alexander BERSHADSKY
Coordinated Regulation of the Actin Cytoskeleton and Microtubule
Dynamics by mDia1 Formin
15:30-15:45 Heather LONG
Subcellular Distribution of Cytoplasmic Linker Proteins in Migrating
Epithelial Carcinoma Cells
15:45-16:00 Alphée MICHELOT
The Formin Homology 1 Domain Modulates the Actin Nucleation and
Bundling Activity of Arabidopsis FORMIN1 (AFH1)
16:00-16:30 COFFEE BREAK
16:30-17:45 Session 4
CYTOSKELETAL DYNAMICS 2
Chair: Christophe Ampe
16:30-17:00 Tijs KETELAAR
Root Hairs: a Model System for Studying Cytoskeletal Dynamics and
Cell Expansion
17:00-17:15 Céline REVENU
What is the Role of Villin in Cell Dynamics ?
17:15-17:30 Gemma BELLETT
Microtubule Plus-End Capture and the Formation of Non-
Centrosomal Microtubule Arrays
17:30-17:45 Roser PINYOL
The Actin Binding Protein ABP1 Interacts with N-WASP and this
Complex May Link Actin Dynamics to Endocytosis
19:30-20:30 DINNER
20:30- Posters and refreshments POSTER SESSION I

Monday 29 August
9:30- 12:00 Session 5 - SPECIAL SESSION
LIVE CELL IMAGING AND EMERGING TECHNOLOGIES
Chair: Mario Gimona
9:30-10:00 Klemens ROTTNER
WASP versus WAVE: Differential Subcellular Distribution, Dynamics
and Function
10:00-10:30 Rainer PEPPERKOK
Studying the Coupling of ER Exit to Microtubules in Living Cells
10:30-11:00 COFFEE BREAK
11:00-10:15 Pirta HOTULAINEN Two Distinct Assembly Mechanisms are Utilized in Generation of the Actin Stress Fiber Network
11:15-11:30 Suha NAFFAR-ABU-AMARA Involvement of Motility- and Adhesion-Related Genes in Tumor Metastasis
11:30-11:45 Julien COLOMBELLI In Vivo Cytoskeleton Dynamics Quantification by Pulsed UV Laser Nanosurgery
12:00-13:50 LUNCH
13:50-15:40 Session 6 NUCLEAR FUNCTION OF CYTOSKELETAL PROTEINS
Chair: Christine Chaponnier
13:50-14:20 Richard TREISMAN Coupling Cytoskeletal Dynamics to the Regulation of Gene Transcription
14:20-14:50 Roland FOISNER Lamina Proteins in Nuclear Architecture, Dynamic Chromatin Organization and Cell Cycle Control
14:50-15:15 Avri BEN-ZE'EV Nuclear Function of Cytoskeletal Proteins: Coordinating Adhesion and Transcription by Novel Target Genes of Cadherin-Catenin Signaling in Colon Cancer
15:15-15:30 Jens GRUBER
RNAi of FACE1 Protease Results in Growth Inhibition of Human Cells
Expressing Lamin A; Implications for Hutchinson-Gilford Progeria
Syndrome
15:40-16:10 COFFEE BREAK
16:10-17:40 Session 7
MODEL ORGANISMS
Chair: Roger Karlsson
16:10-16-40 Angelika NOEGEL
Dictyostelium, a Model to Assess the Function of Cytoskeletal
Proteins
16:40-17:10 Jürgen WEHLAND
Bacterial Pathogens as Models for the Dissection of Cytoskeleton
Dynamics
17:10-17:25 Raissa ELUERE
A New Role for the Axial Budding Protein Bud3 in Regulating Septins
Network for Cytokinesis in Saccharomyces cerevisiae
17:25-17:40 Sawako YAMASHIRO
UNC-87, C. elegans Calponin-Repeat Protein, Inhibits both F-Actin-
Binding and Severing Activities of ADF/cofilin
19:00-20:00 BUFFET DINNER
20:00- Posters and refreshments POSTER SESSION II

Tuesday 30 August
9:00-12:10 Session 8
INTEGRATED CYTOSKELETAL CIRCUITS
Chair: Daniel Louvard
9:00-9:30 Mary BECKERLE
LIM Proteins: Molecular Scaffolds for Cytoskeletal Regulation and
Signaling
9:30-10:00 Guy TANENTZAPF
Talin: an Essential Link between Integrins and the Cytoskeleton
10:00-10:30 Monique ARPIN
Plasma Membrane Organization and Cell Growth Signaling by the
Membrane-Cytoskeleton Linker Ezrin
10:30-11:00 COFFEE BREAK
11:00-11:30 Giorgio SCITA Signaling Complexes Regulating Actin Nucleation and Barbed End Capping Activity
11:30-11:45 Chen LUXENBURG The Src-Cortactin Pathway Regulates Podosome Dynamics During Osteoclast Polarization
11:45-12:00 Pierre-Jean WIPFF Mechanical Stress Induces Immediate TGF-b Activation in Myofibroblast Culture
12:45-13:45 LUNCH
13:45-15:30 Posters + coffee POSTER SESSION III
15:30-20:00 Excursion to the Moselle (boat trip, visit of a winery + wine tasting)
20:00 GALA DINNER Poster prizes

Wednesday 31 August
9:00-10:30 Session 9
BIOPHYSICS OF THE CYTOSKELETON
Chair: Benny Geiger
9:00-9:30 Cécile SYKES
Biomimetic Systems to Study Actin-Based Movement and Force
Generation
9:30-10:00 Marileen DOGTEROM
Dynamics of Force-Generating Microtubules and Microtubule Bundles
10:00-10:15 Laurent KREPLAK
Evaluating the Mechanics of Single IFs In Vitro -towards
Understanding the Mechanical Role of Ifs In Situ
10:15-10:30 Jan W. VOS
Measuring and Modeling Microtubule Organisation in Interphase
Tobacco BY-2 Cells
10:30-11:00 COFFEE BREAK
11:00-12:15 Session 10 CYTOSKELETON AND DISEASE
Chair: Olli Carpen
11:00-11:30 FRANS RAMAEKERS Mechanical Weakness of Nuclei and Cells in Laminopathies Result from Both Lamin Disorganization land Cytoskeletal Abnormalities
11:30-12:00 John S. CONDEELIS The Invasion Signature of Mammary Tumours: Insights into Cell Signalling and Motility
12:00-12:15 Johan DE ROOIJ Integrin-Dependent Acto-Myosin Contraction Regulates Epithelial Cell Scattering
12:15-14:00 LUNCH
DEPARTURE