The crystal structures of human S100B in the zinc- and calcium-loaded state at three pH values reveal zinc ligand swapping.

S100B is a homodimeric zinc-, copper-, and calcium-binding protein of the family of EF-hand S100 proteins. Zn(2+) binding to S100B increases its affinity towards Ca(2+) as well as towards target peptides and proteins. Cu(2+) and Zn(2+) bind presumably to the same site in S100B.

Structural and functional insights into RAGE activation by multimeric S100B.

Nervous system development and plasticity require regulation of cell proliferation, survival, neurite outgrowth and synapse formation by specific extracellular factors. The EF-hand protein S100B is highly expressed in human brain. In the extracellular space, it promotes neurite extension and neuron survival via the receptor RAGE (receptor for advanced glycation end products).

Expression and purification of the soluble isoform of human receptor for advanced glycation end products (sRAGE) from Pichia pastoris.

RAGE is a multi-ligand receptor involved in various human diseases including diabetes, cancer or Alzheimer's disease. Engagement of RAGE by its ligands triggers activation of key cellular signalling pathways such as the MAP kinase and NF-kappaB pathways. Whereas the main isoform of RAGE is a transmembrane receptor with both extra- and intracellular domains, a secreted soluble isoform (sRAGE), corresponding to the extracellular part only, has the ability to block RAGE signalling and suppress cellular activation.

Purification, crystallization and preliminary X-ray diffraction studies on human Ca2+-binding protein S100B.

S100B, a Ca2+-binding protein, acts intracellularly as a Ca2+-signalling protein but is also secreted to the extracellular space, acting in a cytokine-like manner through its receptor RAGE. Recombinant human S100B has been purified and crystallized in the Ca2+-bound state. Size-exclusion chromatography indicates that S100B can exist as a dimer and as a multimer in solution.