Fibronectin receptor

Fibronectin receptor is a two-chain glycoprotein of the integrin family that serves as a transmembrane linker by binding to talin on the cytoplasmic side and to fibronectin on the external side of the membrane. The pull exerted by stress fibers on attached structures may be produced by bipolar assemblies of nonmuscle myosin molecules producing a sliding of actin filaments of opposite polarity. 

Figure 48-5. Schematic representation of fibronectin interacting with an integrin fibronectin receptor situated in the exterior of the plasma membrane of a cell of the ECM and of various attachment proteins interacting indirectly or directly with an actin microfilament in the cytosol. For simplicity, the attachment proteins are represented as a complex.

Duband, J.-L., Nuckolls, G., Ishihara, A., Hasegawa, T., Yamada, K., Thiery, J.P., and Jacobson, K. (1988) Fibronectin receptor exhibits high lateral mobility in embryonic locomoting cells but is immobile in focal contacts and fibrillar streaks in stationary cells./. Cell Biol. 107, 1385-1396. 

CR1 and CR3. Thus, it is envisaged that occupancy of fibronectin receptors somehow also activates CR1 and CR3. 

Other adhesion receptors that are structurally and functionally related include the receptors for fibronectin, vitronectin, platelet glycoproteins 13b and Ilia and the VLA (very-late antigen) series. All molecules involved in adhesion recognise the RGD motif and require the divalent cations Ca2+ and Mg2+ for binding. All are dimers of glycosylated proteins with relative molecular masses 95-190 kDa. There is also some sequence homology between the /J-chain (CD18) and one chain of the fibronectin receptor. 

Froman, G., Switalski, L., Speziale, P., and Hook, M. (1987). Isolation and characterization of a fibronectin receptor from Staphylococcus aureus, f. Biol. Chem. 262,6564-6571. 

Schematic illustration of a so-called focal contact, showing how extracellular fibronectin is believed to be indirectly attached to the intracellular cytoskeleton through a transmembrane fibronectin receptor and several other peripheral membrane proteins.

Bogaert TN, Brown N, Wilcox M. The Drosophila PS2 antigen is an invertebrate integrin that, like the fibronectin receptor, becomes localized to muscle attachments. Cell 1987 51 929-940. 

Akiyama, S. K., Yamada, S. S., Chen, W. T. and Yamada, K. M. (1989). Analysis of fibronectin receptor function with monoclonal antibodies roles in cell adhesion, migration, matrix assembly, and cytoskeletal organization. J. Cell Biol. 109, 863-875. 

Giancotti, F. G. and Ruoslahti, E. (1990). Elevated levels of the alpha 5 beta 1 fibronectin receptor suppress the transformed phenotype of Chinese hamster ovary cells. 60, 849-859. 

Stallmach, A., von Lampe, B., Orzechowski, H. D., Matthes, H. and Riecken, E. O. (1994). Increased fibronectin-receptor expression in colon carcinoma-derived HT 29 cells decreases tumorigenicity in nude mice. Gastroenterology 106, 19-27. 

The evidence is increasing that glycosylation of integrins plays important modulatory roles in the function of these molecules. In other studies it appears that the glycosylation of at least one extracellular matrix glycoprotein, namely laminin, is important in cellular adhesion mediated by integrins. So far most information on the role of carbohydrates in integrin-mediated adhesive interactions has been obtained for the fibronectin receptors... 

Tang DG, Chen YQ, Diglio CA, Honn KV. Protein kinase C-dependent effects of 12(S)-HETE on endothelial cell vitronectin receptor and fibronectin receptor. J Cell Biol. 121... 

Duband, J.L., Rocher, S., Chen, W.T., Yamada, K.M. and Thiery, J.P. (1986) Cell adhesion and migration in the early vertebrate embryo location and possible role of the putative fibronectin receptor complex. J. Cell Biol. 102 160-178. 

Cohen, J., Burne, J.F., McKinley, C. and Winter, J. (1987) The role of laminin and the laminin/fibronectin receptor complex in the outgrowth of retinal ganglion cell axons. Dev. Biol. 122 407-418. 

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