Program
| MSB3 | Woodward 3; 3:30 pm - 5:30 pm, July 27 |
|---|---|
| Title | Intermediate filaments - Part II |
| Organizer | Stephanie Portet |
| University of Manitoba | |
| Abstract | The cytoskeleton is an arrangement of structural proteins organized in three networks: microfilaments (MF), intermediate filaments (IF) and microtubules (MT). Each network has specific physical properties and spatial organization as well as particular roles in the cell. The organization of a cytoskeletal network is the main determinant of its function in cells. MF and MT networks have been extensively studied theoretically and experimentally for the last 40 years. On the contrary, works on IFs are less numerous. For instance, the mechanical properties of single filaments were unknown until recently (Kreplak, 2005), and so far only a few mathematical models studying the organization of IFs has been proposed (Beil, 2009, Craciun, 2005, Kirmse, 2007, Portet, 2003, 2009). IFs are involved in the mechanical resilience of the cell, cell migration and signal transduction. IFs differ from the two other networks in terms of subunits structure, mode of filament assembly and network organization but also in terms of mechanical properties exhibited by a single filament and the whole network. For instance, IFs are formed from fibrous proteins; they are non-polar and necessitate neither ATP nor GTP to assemble. Filaments self-interact without any crosslinker proteins. IFs are highly flexible polymers with a lower persistence length than MFs and MTs. Furthermore, IFs exhibit a specific viscoelastic behavior called strain stiffening (Kreplak, 2007, Wagner, 2007). More and more diseases have been associated to mutations of IF genes. These mutations are not well understood, but they affect the assembly of filaments and their integration into networks and in fine result in changes of their viscoelastic properties. Defects in the IF network organization are correlated to different human pathologies such as myopathies, and neurodegenerative disorders. Understanding the organization mechanisms of IFs and the link between the network architecture and its viscoelastic properties is essential. This interdisciplinary symposium, focused on IFs, will provide a forum for discussions between experimental and modeling approaches. References: Beil, M. et al (2009) J Theor Biol. 256: 518 Craciun, G. et al (2005) J Theor Biol. 237: 316 Kirmse, R. et al (2007) J Biol Chem. 282:18563 Kreplak, L. et al (2005) J Mol Biol 354: 569 Kreplak, L. et al (2007) BioEssays 29: 26 Portet, S. et al (2003) J Theor Biol. 223: 313 Portet, S. et al (2009) Math Bio Eng. 6: 117 Wagner, O. et al (2007) Exp Cell Res. 313: 2228 |
| Speaker 1 | Markus Meier |
| Department of Chemistry, University of Manitoba | |
| Biophysical characterization of vimentin coil 1A, a molecular switch | |
| Speaker 2 | Laurent Kreplak |
| Structural nanomechanics lab, Department of Physics and Atmospheric Science, Dalhousie University | |
| Nanomechanics of self-assembled protein filaments | |
| Speaker 3 | Paul Janmey |
| Departments of Physiology, Physics, Bioengineering, University of Pennsylviana | |
| Assembly and mechanics of intermediate filaments | |
| Speaker 4 | Gheorghe Craciun |
| Department of Mathematics and Department of Biomolecular Chemistry University of Wisconsin-Madison | |
| Dynamical system models of neurofilament transport in axons |
Link to Part I - MSA3
-- Minisymposium talks are scheduled for 30 min each, including time for questions.