Arg-Gly-Asp sequence

Endothelial cell adhesion to surface-immobilized fibrinogen results in structural changes to the cells, including microfilament reorganization and cellular spreading. These interactions appear to be mediated by civ/33 binding to the Arg-Gly-Asp sequence in the C-terminal Act chain (Cheresh et al., 1989 Dejana et al., 1988 Francis et al., 1993 Suehiro et al., 1997). In... 

The structural basis for binding of the prototypical Arg-Gly-Asp sequence to the avp3 integrin was recently provided by the crystal structure of 35 complexed with the extracellular segment of integrin avP3 [48] as shown in Figure 1.13. 

To mimic the macromolecular-based ECM in biological tissue, the cell adhesion and proliferation properties of hydrogels are critical parameters. However, various hydrogels that originate from natural resources, such as alginate [87], chitosan [88, 89], and hyaluronic acid [90], and that are synthetically created, such as poly (7V-isopropylacrylamide) (PNIPAAm) [91], PEO [92], PVA [93], and poly(ethylene glycol) (PEG) [94], show a poor cellular viability without modification with cell adhesive proteins or peptides, such as collagen, laminin, fibronectin, and the RGD (Arg-Gly-Asp) sequence. 

Dedhar, S. Ruoslahti, E. Pierschbacher, M. D. A cell surface receptor complex for collagen type I recognizes the Arg-Gly-Asp sequence. J. Cell. Biol. 1987, 104, 585-593. 

The level of structure described as primary corresponds to the distribution of the 20 protein residues along the macromolecular chain. To indicate the arrangement of the various comonomeric units in the polypeptide sequences, it is necessary to give an abbreviation to each residue, corresponding to the first letters of the amino acid. For example, the -Arg-Gly-Asp- sequence is known to exhibit antithrombogenic properties that are used in biomedical engineering. 

The binding of integrins to certain ligands is mediated by a short amino acid sequence. Thus, the binding site for fibronectin is confined to a sequence of four amino acid residues, Arg-Gly-Asp-Ser (RGDS) (R7). Synthetic peptides containing the RGDS sequence prevented adhesion of cells to fibronectin (B4, R7) and also inhibited metastasis formation in animal models (B4, R7). 

The domain structure in fibronectins is made up of a few types of peptide module that are repeated numerous times. Each of the more than 50 modules is coded for by one exon in the fibronectin gene. Alternative splicing (see p. 246) of the hnRNA transcript of the fibronectin gene leads to fibronectins with different compositions. The module that causes adhesion to cells contains the characteristic amino acid sequence -Arg-Gly-Asp-Ser-. It is these residues that enable fibronectin to bind to cell-surface receptors, known as integrins. 

Brandley and Schnaar [140] immobilized a synthetic nonapeptide, Tyr- Ala-Val Thr-Gly Arg-Gly-Asp-Ser, on a polyacrylamide gel, which had been prepared by a ternary copolymerization of acrylamide, bisacrylamide and the acrylic ester of. V-hydroxysuccinimide. They reported that Balb/c 3T3 mouse fibroblast cells (in Hepes-buffered Dulbecco s modified Eagle medium) adhered readily to the peptide-derivatized surfaces, even in the absence of serum, although long-term cell growth required the presence of serum. It was noticed that reference nonapeptide. Tyr-Arg-Leu-Glu-Asp-Pro-Ala-Met-Trp, which has no RGD sequence, failed to promote cell-attachment. 

Archaeobacteria 7, 815 Area detector for X-rays 134 Arg-Gly-Asp (RGD) sequence 408 Arginase 888... 

All of the oncosphere antigens cloned to date contain either one of two copies of a predicted Fnlll domain. These domains are widely distributed in eukaryotic proteins and occur also in some prokaryotic proteins (Bork and Doolittle, 1992). Approximately 2% of animal proteins include Fnlll domains. Many, but not all, of these proteins are extracellular and some have roles as adhesins. The structure of this 100 amino acid domain is highly conserved and consists of two layers with three p strands in one plane and four p strands in another (Potts and Campbell, 1996). Overall, amino acid sequence identity between different Fnlll domains is low, even between Fnlll repeat domains within fibronectin itself (Plaxco et al., 1997). Nevertheless, certain residues are highly conserved and maintain the tertiary structure of the proteins (Bork and Doolittle, 1992). Other conserved motifs such as an Arg-Gly-Asp (RGD) motif within a loop of some Fnlll domains is associated with proteins having cell adhesion properties, as discussed above (Ruoslahti and Pierschbacher, 1987 D Souza et al., 1991). 

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