|Protein Name||Protein S100-B|
|Ref Sequence Id||NP_001029727.1|
|Amino Acid Lenth||92|
|Protein Existence Status||Reviewed: Experimental evidence at protein level|
|Presence in other biological fluids/tissue/cells||S100B is expressed in astrocytes, certain neuronal populations, Schwann cells, melanocytes, chondrocytes, adipocytes, skeletal myofibers and associated satellite cells, certain dendritic cell and lymphocyte populations and a few other cell types;|
|Protein Function||it acts as a cytokine with a neurotrophic effect at physiological concentrations; acts as a stimulator of cell proliferation and migration and an inhibitor of apoptosis and differentiation;have important implications during brain, cartilage and skeletal muscle development and regeneration/repair, activation of astrocytes in the course of brain damage and neurodegenerative processes, and of cardiomyocyte remodeling after infarction, as well as in melanomagenesis and gliomagenesis; regulate a large variety of key activities including maintenance of shape, transcription, protein degradation, Ca2+ homeostasis, energy metabolism and enzyme functions by interacting with a wide array of target proteins;|
|Biochemical Properties||acidic calcium-binding protein of the EF-hand family, characterised by the most common calcium-binding motif of a helix–loop–helix structure; Binding partners of S100B within cells are tubulin and the microtubule-associated τ protein, the actin-binding protein caldesmon, calponin, type III intermediate filament subunits, annexin 6, membrane-bound guanylate cyclase, the small GTPase Rac1 and Cdc42 effector IQGAP1, Src kinase, the serine/threonine protein kinase Ndr, the tumor suppressor p53, intermediates upstream of IKKβ/NF-κB, the giant phosphoprotein AHNAK/desmoyokin, the E3 ligase hdm2, dopamine D2 receptor and the mitochondrial AAA ATPase, ATAD3A; changes in extracellular Ca2+ and K+ levels trigger release of S100B from astrocytes and fluoexitine stimulates S100B secretion from serotoninergic neurons;|
|Significance in milk||Human milk S100B protein possesses important neurotrophic properties; As found in human milk, S100B concentration increases as the milk matures|
|PDB ID||1CFP, 1MHO, 1PSB, 3CR2, 3CR4, 3CR5, 3GK1, 3GK2, 3GK4, 3IQO, 3IQQ, 3LK0, 3LK1, 3LLE, 3RLZ, 3RM1, 4FQO, 4PDZ, 4PE0, 4PE1, 4PE4, 4PE7, 5DKN, 5DKQ, 5DKR, 5ER4, 5ER5,|
|Bibliography||1. Gazzolo, D. et al. (2004) ‘Levels of S100B protein are higher in mature human milk than in colostrum and milk-formulae milks.’, Clinical nutrition (Edinburgh, Scotland), 23(1), pp. 23–6. Available at: http://www.ncbi.nlm.nih.gov/pubmed/14757389 (Accessed: 3 October 2019). |
2. Hachem, S. et al. (2007) ‘Expression of S100B during embryonic development of the mouse cerebellum’, BMC Developmental Biology, 7(1), p. 17. doi: 10.1186/1471-213X-7-17.
3. Donato, R. (1984) ‘Mechanism of action of S-100 protein(s) on brain microtubule protein assembly.’, Biochemical and biophysical research communications, 124(3), pp. 850–6. doi: 10.1016/0006-291x(84)91035-0.
4. Gilquin, B. et al. (2010) ‘The Calcium-Dependent Interaction between S100B and the Mitochondrial AAA ATPase ATAD3A and the Role of This Complex in the Cytoplasmic Processing of ATAD3A’, Molecular and Cellular Biology, 30(11), pp. 2724–2736. doi: 10.1128/MCB.01468-09.