S100 proteins

Ca2+-sensing Receptor Calpains Protein Phosphates S100 Proteins... 

S100 proteins (named because of their solubility in a 100% ammonium sulfate solution) constitute the largest family within the EF-hand Ca2+-binding proteins superfamily [1]. SI00 proteins are small, acidic proteins containing two distinct Ca2+-binding EF-hand structural motifs [2]. The C-terminal EF-hand contains the... 

S100 Proteins. Table 1 Nomenclature9 and chromosomal location of the S100 genes... 

S100 Proteins. Figure 1 Pathways of Ca2+-release and uptake. 

S100 Proteins. Table 2 S100 proteins in human diseases... 

S100 Proteins. Table 3 S100 proteins in clinical diagnostics... 

Monkey (Rhesus) 9 yr (F) 7 (decrease content of S100 protein in hippocampal glia cells) Noack et al. 1996 PbAc... 

A protein highly homologous to the S100 proteins has been isolated from Ehrlich ascites tumor cells it has subsequently been shown to be nearly identical with human calcyclin. The fluorescence intensity from the three tyrosine residues is enhanced on the binding of Ca2+.(l58)... 

J. Baudier and D. Gerard, Ions binding to S100 proteins Structural changes induced by calcium and zinc on SlOOa and SlOOb proteins, Biochemistry 22, 3360-3369 (1983). 

Abstract The S100 proteins are exclusively expressed in vertebrates and are the largest subgroup... 

Here, we review the most recent developments focussing on the biological functions of the S100 proteins and we discuss the presently available S100-specific mouse models and their possible use as human disease models... 

In addition, the SI 00-RAGE interaction and the activation of various cellular pathways will be discussed. Finally, the close association of S100 proteins with cardiomyopathy, cancer, inflammation and brain diseases is summarized as well as their use in diagnosis and their potential as drug targets to improve therapies in the future... 

Keywords Calcium, EF-hand, S100 proteins, human diseases, RAGE... 

Table 2. Involvement of S100 Proteins in Human Diseases...

Structural analyses have revealed a typical architecture of the S100 proteins. Each S100 protein is composed of two EF-hand Ca2+-binding domains connected by a central hinge region (Fritz and Heizmann, 2004 Bhattacharya et al., 2004 ... 

Vallely et al., 2002 Ikura and Ames, 2006). The C-terminal EF-hand contains the classical Ca2+-binding motif, common to all EF-hand proteins (see above). This Ca2+-binding motif has a typical sequence signature of 12 amino acids and is flanked by helices Hin and HIV. The N-terminal EF-hand is different from the classical EF-hand motif and is characteristic of the S100 proteins. Therefore, this EF-hand, with a 14 amino acid consensus sequence motif, is flanked by helices H, and Hn and is called the SlOO-specific or pseudo EF-hand. 

Some S100 proteins e.g. S100A9 have long and flexible C-terminal extensions, which might be required for target interaction independently of calcium binding. 

In general, the C-terminal end exhibits the highest sequence variation and therefore may contribute to the specificity of the different S100 proteins (Marenholz et al., 2004a Bhattacharya et al., 2004 Wilder et al., 2006). 

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