Glomerular basement membrane proteins

As noted above, the presence of Met(O) in proteins would go undetected after acid hydrolysis and subsequent amino acid analysis. Thus, since this method of hydrolysis is most commonly used, it is impossible to ascertain from the literature the abundance of Met(O) residues normally present in proteins. However, a number of studies have reported the presence of Met(O) residues in various proteins using one of the appropriate procedures described above. It has been found that Met(O) residues comprise 30% of the total Met in proteins isolated from bovine glomerular basement membranes and anterior lens . Other investigators have reported that the levels of Met(O) in proteins of the trabecular meshwork of human eyes increased with the age of the donor . The amount of Met(O) detected ranged from 15% (10 years old) to 55% (79 years old) of the total methionine content found in the tissue samples. Other studies have shown that in certain species of clams the proteins of the hinge ligament contain only Met(0) residues and no Met . In addition, it has also been reported that as much as 18% of the Met residues in pea seed proteins is in the form of Met(O) . Lastly, Met(O) residues have been found in... 

GAP GTPase-activating protein GBM Glomerular basement membrane... 

Daniels, B.S., Hauser, E.B.,Deen, W.M. and Hostetter, T.H. (1992) Glomerular basement membrane in vitro studies of water and protein permeability. Am. J. Physiol., 262, F919-F926. de Gennes, P.G. (1979) Scaling Concepts in Polymer Physics. Cornell University Press, Ithaca. 

Laminin [consisting of three polypeptide chains, A, Bl (possibly replaced in GBM by S) and B2] is the most important noncollagenous protein of the glomerular basement membrane. Laminin forms a second network, which is connected to the collagen IV network probably via another protein called entactin or nidogen. Laminin is probably very important for cellular differentiation and adhesion, but its mesh clearly also contributes to the structure of the glomerular basement membrane. The postnatally common embryonic laminin-10 isoform is... 

Congenital nephrotic syndrome of the Finnish type is clinically characterized by heavy proteinuria present already in utero, which leads without nephrectomy and renal replacement therapy to the death of the affected children usually before the second year of life. Electronoptically, the glomerular basement membrane seems to be intact with the fusion of the podocyte foot processes. The chemical composition of the glomerular basement membrane is normal in patients with congenital nephrotic syndrome and all genes of the main proteins of the glomerular... 

Charge selectivity is probably mediated mainly by the polyanionic glycosamino-glycans present in the glomerular basement membrane (C5, G6). This barrier restricts mostly the movement of relatively small polyanionic proteins (molecular weight 70-150 kDa), mainly albumin. Loss of charge selectivity is believed to be the main cause of albuminuria (selective proteinuria) in minimal change disease (B10). 

Heikkila, P., Tibell, A., Morita, T., Chen, Y., Wu, G., Sado, Y., Ninomiya, Y., Pettersson, E. and Tryggvason, K. (2001). Adenovirus-mediated transfer of type IV collagen alpha5 chain cDNA into swine kidney in vivo Deposition of the protein into the glomerular basement membrane. Gene Ther. 8, 882-890. 

The major components of beef glomerular basement membrane were solubilized with sodium dodecyl sulphate and resolved on 6% agarose [229]. 0.1% SDS has also been used in the separation of lipoprotein and apolipoprotein from human plasma [230] and 3% SDS used in gel chromatography of human erythrocyte membranes on Sepharose 6B [231]. Stokes radius determination of insulin-binding protein was performed on Sepharose 6B with 0.5% Triton X-100 [232]. 

Daniels BS, Hauser EB, Deen MW, Hostetter TH. Glomerular basement membrane In vitro studies of water and protein permeability. Am J Physiol 1992 262 F919-26. 

Little attention has been devoted to the relation of late browning reactions to human metabolism. However, in considering long-lived proteins in man (e.g., lens crystallins, collagens, glomerular basement membrane), it is apparent that such reactions may be relevant to aging processes. 

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