Previous cell biological studies demonstrated that S100B protein enhances neurite extension of cortical neurons and stimulates proliferation of glial cells. Although these activities of the protein are ascribed to its disulfide-linked dimeric form, there have been no indications as to how the dimer is formed in vivo. We have found by an in vitro study that it is produced by copper-dependent oxidation of noncovalent S100B dimer. The disulfide-linked dimer markedly stimulated nitric oxide production in a microglial cell line, BV2. Interestingly, the disulfide-linked dimer formation was found to be prevented by ascorbic acid. The copper-dependent formation of the dimer may not happen in vivo under normal conditions; however, under pathological conditions where copper is likely to be released from tissues and catalyze autoxidation of ascorbic acid, the dimer formation may proceed, resulting in the stimulated production of nitric oxide that would induce toxic signaling pathways. (C) 2000 Academic Press.
|Number of pages||5|
|Journal||Archives of Biochemistry and Biophysics|
|State||Published - Feb 15 2000|
Bibliographical noteFunding Information:
1This work was supported in part by Grant-in-Aid 08457055 for Scientific Research from the Ministry of Education, Science, Sports, and Culture of Japan, by a Grant-in-Aid from Fujita Health University, and by National Institutes of Health Grant AG13939.
- Ascorbic acid
- Nitric oxide
- S100B protein
ASJC Scopus subject areas
- Molecular Biology