Paul A. Janmey, Ph.D.
Professor of Physiology
Department: Physiology
Graduate Group Affiliations
Contact information
Institute for Medicine and Engineering
University of Pennsylvania
1010 Vagelos Research Laboratories
3340 Smith Walk
Philadelphia, PA 19104-6383
University of Pennsylvania
1010 Vagelos Research Laboratories
3340 Smith Walk
Philadelphia, PA 19104-6383
Office: 215 573-7380
Fax: 215 573-6815
Fax: 215 573-6815
Email:
janmey@mail.med.upenn.edu
janmey@mail.med.upenn.edu
Publications
Education:
A.B. (Chemistry and Philosophy)
Oberlin College, 1976.
Ph.D. (Physical Chemistry)
University of Wisconsin, 1982.
Permanent linkA.B. (Chemistry and Philosophy)
Oberlin College, 1976.
Ph.D. (Physical Chemistry)
University of Wisconsin, 1982.
Description of Research Expertise
Research Interestscytoskeleton, phosphoinositide signalling, cell mechanics.
Key words: actin, PIP2, cytoskeleton, gel, astrocyte, fibrin, gelsolin.
Description of Research
Our lab studies several aspects of cell mechanics. In one project, we produce soft materials, usually hydrogels, to which cell adhesion proteins are linked to study how the stiffness of surfaces alters cell structure, function, and growth. Endothelial cells, fibroblasts, neurons and astrocytes each show unique dependence on substrate stiffness, and we seek to understand how they sense and respond to this mechanical cue. In related work we measure the structure and mechanics of cytoskeletal polymers using a variety of imaging, scattering, and rheologic methods. Further studies examine how changes in cell membrane structure mediated by inositol phospholipids lead to production of signals that remodel the cytoskeleton.
Rotation Projects for 2009-2010
1. Image morphology and cytoskeletal changes in GFP-actin or GFP-vimentin expressing fibroblasts, endothelial cells, and other cell types grown of soft materials.
2. Fluorescence and atomic force microscopy of purified cytoskeletal polymers and associated motor proteins.
3. Use of fibrin gels as matrices for cell culture.
Lab personnel:
Robert Bucki, Fitzroy Byfield, Andrew Charlton, Yuning Chien, Katrina Cruz, Andrew Fang, Mariana Hernandez, Liesbeth Huisman, Maria Murray, Shaina Oake, JT Sauls, David Slochower, Erdem Tabdanov, Shang Tee, Eric Wang, Qi Wen, Tracy Wolfbiss
Selected Publications
Tee, SY, Bausch, A. R., Janmey, PA: The mechanical cell. Curr Biol Page: in press, 2009.Winer, J. P., Oake, S., Janmey, P. A.: Non-linear elasticity of extracellular matrices enables contractile cells to communicate local position and orientation. PLoS One 4(7): e6382, 2009.
Levental, I., Christian, D. A., Wang, Y. H., Madara, J. J., Discher, D. E., Janmey, P. A.: Calcium-dependent lateral organization in phosphatidylinositol (4,5) bisphosphate (PIP2)- and cholesterol-containing monolayers. Biochemistry 2009.
Byfield, F. J., Wen, Q., Levental, I., Nordstrom, K., Arratia, P. E., Miller, R. T., Janmey, P. A.: Absence of filamin A prevents cells from responding to stiffness gradients on gels coated with collagen but not fibronectin. Biophys J 96(12): 5095-102, 2009.
Winer, J. P., Janmey, P. A., McCormick, M. E., Funaki, M.: Bone Marrow-Derived Human Mesenchymal Stem Cells Become Quiescent on Soft Substrates but Remain Responsive to Chemical or Mechanical Stimuli. Tissue Eng Part A 15(1): 147-154, 2009.
Janmey, P. A., Winer, J. P., Murray, M. E., Wen, Q.: The hard life of soft cells. Cell Motil Cytoskeleton 2009.
Levental, I., Cebers, A., Janmey, P. A.: Combined electrostatics and hydrogen bonding determine intermolecular interactions between polyphosphoinositides. J Am Chem Soc 130(28): 9025-30, 2008.
Bucki, R., Byfield, F. J., Kulakowska, A., McCormick, M. E., Drozdowski, W., Namiot, Z., Hartung, T., Janmey, P. A.: Extracellular gelsolin binds lipoteichoic acid and modulates cellular response to proinflammatory bacterial wall components. J Immunol 181(7): 4936-44, 2008.
Janmey, P. A., McCormick, M. E., Rammensee, S., Leight, J. L., Georges, P. C., Mackintosh, F. C.: Negative normal stress in semiflexible biopolymer gels. Nat Mater 6(1): 48-51, 2007.
Janmey, P. A., McCulloch, C. A.: Cell Mechanics: Integrating Cell Responses to Mechanical Stimuli. Annu Rev Biomed Eng 9: 1-34, 2007.