Secreted protein, acidic and rich

CS-PG, chondroitin sulfate-proteoglycan these are similar to the dermatan sulfate PGs (DS-PGs) of cartilage ffable 48-11). SPARC, secreted protein acidic and rich in cysteine. 

SPARC (Secreted Protein Acidic and Rich in Cysteine), 46 484-485 Specific activity method, of isotope half-life determination, 2 326-327 Specific interaction theory, application, 43 19-21... 

Puolakkainen P, Bradshaw AD, Kyriakides TR, Reed M, Brekken R, Wight T, Bomstein P, Ratner B, Sage EH. Compromised production of extracellular matrix in mice lacking secreted protein, acidic and rich in cysteine (SPARC) leads to a reduced foreign body reaction to implanted biomaterials. American Journal of Pathology 2003,162, 627-635. 

Bleomycin (0.15 U/mouse) given intratracheally induced significantly more pulmonary fibrosis in mice deficient in SPARC (secreted protein, acidic and rich in cysteine) compared with that in wild-type control mice, with the mutant mice demonstrating greater neutrophil accumulation in the lungs (Savani et al. 2000). However, in wild-type and SPARC-deficient mice given intraperitoneal bleomycin (0.8 U/injectionx 5 injections over 14 days), the pattern and severity of pulmonary fibrosis, as well as the levels of leucocyte recruitment, were similar in both strains of mice. 

Secreted protein, acidic and rich in cysteine (SPARC) is a multifunctional glycoprotein found within the extracellular matrix in a variety of tissues. It was found to be consistently upregulated in microarray analyses of tissue from scleroderma patients, and three new SNPs were found by sequencing the gene in... 

A second category of NCPs with Ca-binding properties is classified as mineraUzed tissue specific, since they are found in all the calcified connective tissues, namely, dentin, bone, and cementum. These proteins include osteocalcin (OC) and bone sialoprotein (BSP). A serine-rich phosphoprotein called dentin matrix protein 1 (Dmp-1), whose expression was first described as being restricted to odontoblasts [5], was later shown to be expressed by osteoblasts and cementoblasts [6]. Other NCPs include osteopontin and osteonectin [secreted protein acidic and rich in cysteine (SPARC)]. The fourth category of dentin NCPs is not expressed in odontoblasts but is primarily synthesized in the liver and released... 

The whey produced during cheese and casein manufacturing contains approximately 20% of all milk proteins. It represents a rich and varied mixture of secreted proteins with wide-ranging chemical, physical and functional properties (Smithers et al., 1996). Due to their beneficial functional properties, whey proteins are used as ingredients in many industrial food products (Cheftel and Lorient, 1982). According to Kinsella and Whitehead (1989), functional properties of foods can be explained by the relation of the intrinsic properties of the proteins (amino acid composition and disposition, flexibility, net charge, molecular size, conformation, hydrophobicity, etc.), and various extrinsic factors (method of preparation and storage, temperature, pH, modification process, etc.). 

The other major protein in the extracellular matrix is elastin, which is the main component of elastic fibers found in ligaments, large arteries, and lungs. After synthesis and partial hydroxylation of proline residues, a 72 kDa molecule of tropoelastin is secreted into the matrix. This protein is rich in nonpolar amino acids and contains repeating sequences, such as (Val-Pro-Gly-Val-Gly). These sections form an amorphous, random-coiled structure with frequent reverse turns. Other recurrent sequences are rich in alanine with paired lysine residues, e.g., -Ala-Ala-Ala-Ala-Lys-Ala-Ala-Lys-... 

As noted earher (Sect. 12.1.3), the reduced enamel epithelium is replaced with adherent salivary proteins, mostly amylase and acidic proline-rich proteins. The acidic PRPs are at about a three times greater concentration than in secreted saliva. The acidic domain of these proteins especially has a high affinity for hydroxyapatite. Once bound to pelhcle, the N-terminus of acidic-PRPs forms an attachment site for the major classes of commensal bacteria (viridans streptococci and Actinomyces spp.) that occupy the mucosal surfaces and saliva of a healthy oral cavity. Some streptococci grow by themselves in dental biofilms, but many others grow better if certain Actinomyces spp. are also present. 

The salivary proline-rich proteins have a two-domain structure, a proline poorN-terminal domain that is acidic or basic and determines enamel binding, and a proline-rich C-terminal domain that determines bacterial binding. Individual variations in acidic proline-rich proline allelic composition and in the amount of salivary agglutinin, a secreted innate immunity protein that binds bacteria, may account for differences in biofilm composition and dental caries susceptibility. 

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