| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH |
|
|
|
|||||||
|
|||||||||
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
E-mail contact: j-jones3{at}nwu.edu
To gain insight into the dynamic properties of focal contacts, we induced expression of green fluorescent protein-tagged b3 integrin (GFP-b3) and actinin-1 (GFP-actinin-1) in endothelial cells. Both tagged proteins localize with avb3 integrin in focal contacts distributed towards the periphery of transfected cells. Labeled focal contacts migrate at about 0.1 mm/min in stationary live endothelial cells. We compared b3 integrin and actinin-1 dynamics in focal contacts by using fluorescence recovery after photobleaching. Recovery of signal in bleached focal contacts that have incorporated actinin-1 is rapid and occurs within less than 4 min. This recovery is energy-dependent. In contrast, recovery of bleached focal contacts that contain GFP-b3 integrin takes longer than 30 min. Yet, when a narrow stripe of fluorescence is bleached across a b3 integrin-labeled focal contact, recovery is complete within 16 min. The latter recovery is energy-dependent and is blocked not only by actin-filament disrupting drugs but also by a myosin light chain kinase inhibitor. Thus, integrins are not immobile when incorporated into focal contacts, as some have suggested. We propose that integrins are mobile within the confines of focal contacts and that this mobility is supported by an actin-associated molecular motor.
Key words: matrix adhesion · matrix receptors · FRAP · actin cytoskeleton · actinin
This article has been cited by other articles:
|
|
 |
|
  A. M. Malek, C. Xu, E. S. Kim, and S. L. Alper Hypertonicity triggers RhoA-dependent assembly of myosin-containing striated polygonal actin networks in endothelial cells Am J Physiol Cell Physiol, May 1, 2007; 292(5): C1645 - C1659. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 P. J. DeBiase, K. Lane, S. Budinger, K. Ridge, M. Wilson, and J. C.R. Jones Laminin-311 (Laminin-6) Fiber Assembly by Type I-like Alveolar Cells J. Histochem. Cytochem., June 1, 2006; 54(6): 665 - 672. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 T. Shemesh, B. Geiger, A. D. Bershadsky, and M. M. Kozlov Focal adhesions as mechanosensors: A physical mechanism PNAS, August 30, 2005; 102(35): 12383 - 12388. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 T. S. Fraley, C. B. Pereira, T. C. Tran, C. Singleton, and J. A. Greenwood Phosphoinositide Binding Regulates {alpha}-Actinin Dynamics: MECHANISM FOR MODULATING CYTOSKELETAL REMODELING J. Biol. Chem., April 15, 2005; 280(15): 15479 - 15482. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 T. Pompe, L. Renner, and C. Werner Nanoscale Features of Fibronectin Fibrillogenesis Depend on Protein-Substrate Interaction and Cytoskeleton Structure Biophys. J., January 1, 2005; 88(1): 527 - 534. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. Puig-de-Morales, E. Millet, B. Fabry, D. Navajas, N. Wang, J. P. Butler, and J. J. Fredberg Cytoskeletal mechanics in adherent human airway smooth muscle cells: probe specificity and scaling of protein-protein dynamics Am J Physiol Cell Physiol, September 1, 2004; 287(3): C643 - C654. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
A. Nicolas, B. Geiger, and S. A. Safran Cell mechanosensitivity controls the anisotropy of focal adhesions PNAS, August 24, 2004; 101(34): 12520 - 12525. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
G. Giannone, P. Ronde, M. Gaire, J. Beaudouin, J. Haiech, J. Ellenberg, and K. Takeda Calcium Rises Locally Trigger Focal Adhesion Disassembly and Enhance Residency of Focal Adhesion Kinase at Focal Adhesions J. Biol. Chem., July 2, 2004; 279(27): 28715 - 28723. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
H. Delanoe-Ayari, R. Al Kurdi, M. Vallade, D. Gulino-Debrac, and D. Riveline Membrane and acto-myosin tension promote clustering of adhesion proteins PNAS, February 24, 2004; 101(8): 2229 - 2234. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 D. Tsuruta and J. C. R. Jones The vimentin cytoskeleton regulates focal contact size and adhesion of endothelial cells subjected to shear stress J. Cell Sci., December 15, 2003; 116(24): 4977 - 4984. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
A. Chigaev, T. Buranda, D. C. Dwyer, E. R. Prossnitz, and L. A. Sklar FRET Detection of Cellular {alpha}4-Integrin Conformational Activation Biophys. J., December 1, 2003; 85(6): 3951 - 3962. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
D. Tsuruta, S. B. Hopkinson, K. D. Lane, M. E. Werner, V. L. Cryns, and J. C. R. Jones Crucial Role of the Specificity-determining Loop of the Integrin {beta}4 Subunit in the Binding of Cells to Laminin-5 and Outside-in Signal Transduction J. Biol. Chem., October 3, 2003; 278(40): 38707 - 38714. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
G. Mayer, G. Boileau, and M. Bendayan Furin interacts with proMT1-MMP and integrin {alpha}V at specialized domains of renal cell plasma membrane J. Cell Sci., May 1, 2003; 116(9): 1763 - 1773. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH |
