功能 |
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. May mediate calcium-dependent regulation on many physiological processes by interacting with other proteins, such as TPR-containing proteins, and modulating their activity.
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總結(jié) |
The family of EF-hand type Ca2+-binding proteins includes calbindin, S-100 alpha and beta, calgranulins, B and C, and the parvalbumin family members, including parvalbumin alpha and parvalbumin beta. The S-100 protein is involved in the regulation of cellular processes such as cell cycle progression and differentiation. S-100 protein may function in the activation of Ca2+ induced Ca2+ release, inhibition of microtubule assembly and inhibition of protein kinase C mediated phosphorylation. Two S-100 subunits, sharing 60% sequence identity, have been described as S-100 alpha chain and S-100 beta chain. Three S-100 dimeric forms have been characterized, differing in their subunit composition of two alpha chains, two beta chains or one alpha and one beta chain. S-100 localizes to the cytoplasm and nuclei of astrocytes, Schwann s cells, ependymomas and astrogliomas. S-100 is also detected in almost all benign naevi, malignant melanocytic tumours and in Langerhans cells in the skin. Calbindin, S-100 proteins and parvalbumin proteins are each expressed in neural tissues. In addition, S-100 alpha and beta are present in a variety of other tissues and calbindin is present in intestine and kidney.
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別名 |
Protein S100-A1, S-100 protein alpha chain, S-100 protein subunit alpha, S100 calcium-binding protein A1, S100A1, S100A
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