S100B Human Recombinant Protein

The protein encoded by this gene is a member of the S100 family of proteins containing 2 EF-hand calcium-binding motifs. S100 proteins are localized in the cytoplasm and/or nucleus of a wide range of cells, and involved in the regulation of a number of cellular processes such as cell cycle progression and differentiation. S100 genes include at least 13 members which are located as a cluster on chromosome 1q21; however, this gene is located at 21q22.3. This protein may function in Neurite extension, proliferation of melanoma cells, stimulation of Ca2+ fluxes, inhibition of PKC-mediated phosphorylation, astrocytosis and axonal proliferation, and inhibition of microtubule assembly. Chromosomal rearrangements and altered expression of this gene have been implicated in several neurological, neoplastic, and other types of diseases, including Alzheimer's disease, Down's syndrome, epilepsy, amyotrophic lateral sclerosis, melanoma, and type I diabetes. [provided by RefSeq, Jul 2008]

S100B: Weakly binds calcium but binds zinc very tightly- distinct binding sites with different affinities exist for both ions on each monomer. Physiological concentrations of potassium ion antagonize the binding of both divalent cations, especially affecting high-affinity calcium-binding sites. Binds to and initiates the activation of STK38 by releasing autoinhibitory intramolecular interactions within the kinase. Interaction with AGER after myocardial infarction may play a role in myocyte apoptosis by activating ERK1/2 and p53/TP53 signaling. Dimer of either two alpha chains, or two beta chains, or one alpha and one beta chain. The S100B dimer binds two molecules of STK38. Interacts with AGER. The S100B dimer interacts with two molecules of CAPZA1. Although predominant among the water-soluble brain proteins, S100 is also found in a variety of other tissues. Belongs to the S-101 family.

Protein type: Calcium-binding

Chromosomal Location of Human Ortholog: 21q22.3

Cellular Component: ruffle; extracellular space; cell soma; intracellular membrane-bound organelle; perinuclear region of cytoplasm; cytoplasm; extracellular region; nucleus

Molecular Function: identical protein binding; RAGE receptor binding; protein binding; protein homodimerization activity; zinc ion binding; calcium ion binding; tau protein binding; calcium-dependent protein binding

Biological Process: positive regulation of I-kappaB kinase/NF-kappaB cascade; central nervous system development; positive regulation of apoptosis; response to glucocorticoid stimulus; memory; regulation of cell shape; cell proliferation; learning and/or memory; axonogenesis; astrocyte differentiation; response to methylmercury; positive regulation of cell proliferation; innate immune response; regulation of neuronal synaptic plasticity