Proteoglycans cell surface

Valenzuela-Femandez A, Palanche T, Amara A, et al. Optimal inhibition of X4 HIV isolates by the CXC chemokine stromal cell-derived factor 1 alpha requires interaction with cell surface heparan sulfate proteoglycans. J Biol Chem 2001 276(28) 26550-26558. 

Adhesion molecules such as LI, neural cell adhesion molecule (N-CAM) and N-cadherin promote axonal regeneration by homophilic interactions between axons and Schwann cell surfaces (see Ch. 7). The expression of p75 (low affinity NGF receptor, Ch. 27) is also increased at the Schwann cell surface after injury. Extracellular matrix molecules, such as tenascin and proteoglycans, increase the regenerative potential of damaged peripheral nerves by binding to integrins on the axonal surface. 

Fleckenstein, J. M., Holland, J. T., and Hasty, D. L. (2002). Interaction of an outer membrane protein of enterotoxigenic Escherichia coli with cell surface heparan sulfate proteoglycans. Infect. Immun. 70,1530-1537. 

Type I collagen can interact with various other molecules in the extracellular matrix and on the cell surface. Cell receptors of type I collagen have been identified and include the heterodimeric integrin family receptors, ctl, 0 2, olO, and ol 1, especially o2/3l, the receptor tyrosine kinase discoidin domain receptor (DDR), and the heparan sulfate membrane proteoglycan syndecan family... 

Fibronectins are typical representatives of adhesive proteins. They are filamentous dimers consisting of two related peptide chains (each with a mass of 250 kDa) linked to each other by disulfide bonds. The fibronectin molecules are divided into different domains, which bind to cell-surface receptors, collagens, fibrin, and various proteoglycans. This is what gives fibronectins their molecular glue" characteristics. 

Yanagishita, M. and Hascall, V. C. (1992). Cell surface heparan sulfate proteoglycans. J. Biol. Chem. 267, 9451-9454. 

Proteoglycans Are Glycosaminoglycan-Containing Macromolecules of the Cell Surface and Extracellular Matrix... 

Bernfleld, M., Gotte, M., Park, P.W., Reizes, O., Fitzgerald, M.L., Lincecum, J., Zako, M. (1999) Functions of cell surface heparan sulfate proteoglycans. Annu. Rev. Biochem. 68, 729-777. Extensive review of the biological roles of heparan sulfate. 

Here are two of many known examples of specific cell-cell adhesion. The species-specific reaggregation of dissociated cells of marine sponges (Chapter 1) depends upon a 20-kDa proteoglycan of unique structure209-211 together with a cell surface receptor protein and calcium ions. The recognition of egg cell surfaces by sperm212-214 is species... 

In addition to the cytosolic SOD there is a longer 222-residue extracellular form that binds to the proteoglycans found on cell surfaces.522,527 Manganese SODs are found in mitochondria and in bacteria and iron SODs in plants and bacteria. They all appear to be important in protecting cells from superoxide radicals.522/532/533 This importance was dramatically emphasized when it was found that a defective SOD is present in persons (about 1 in 100,000) with a hereditary form of amylotrophic lateral sclerosis (ALS), which is also called Lou Gehrig s disease after the baseball hero who was stricken with this terrible disease of motor neurons in 1939 at the age of 36.534-536... 

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