Extracellular role of S100A4 calcium-binding protein in the periodontal ligament.
S100A4 is a member of the S100 calcium-binding protein family. S100A4 is expressed in several tissues; however, it is secreted by few cell types and its extracellular roles are unknown. In the present study we showed by in situ hybridization that periodontal ligament (PDL) cells express the S100A4 mRNA. Immunolocalization of the S100A4 protein in cryosections of PDL and analyses of PDL cell culture medium revealed that PDL cells secrete the S100A4 protein both in vivo and in vitro. Interestingly, addition of a recombinant mouse S100A4 protein to a bone marrow cell culture inhibited mineralized nodule formation in a concentration-dependent manner. This is the first report of an extracellular role for S100A4 as an inhibitor of mineralization. The PDL space is kept free of mineralization and S100A4 may be one of the factors responsible for such phenomenon.
Faculty of Dentistry, Tokyo Medical and Dental University, Japan. wagner.peri@dent.tmd.ac.jp
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Duarte
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Iimura
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Takenaga
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Ohya
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Ishikawa
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Kasugai
D000818:Animals; D001853:Bone Marrow / Q000502:physiology; D002113:Calcification, Physiologic / Q000187:drug effects; D002135:Calcium-Binding Proteins / Q000502:physiology*; D002417:Cattle; D002478:Cells, Cultured; D005110:Extracellular Space / Q000502:physiology*; D017403:In Situ Hybridization; D008297:Male; D051379:Mice; D010513:Periodontal Ligament / Q000737:chemistry* / Q000166:cytology / Q000378:metabolism; D012333:RNA, Messenger / Q000096:biosynthesis; D051381:Rats; D017208:Rats, Wistar; D011994:Recombinant Proteins / Q000494:pharmacology; D000071999:S100 Calcium-Binding Protein A4; D009418:S100 Proteins / Q000235:genetics / Q000378:metabolism / Q000502:physiology*
D002135:Calcium-Binding Proteins; D012333:RNA, Messenger; D011994:Recombinant Proteins; D000071999:S100 Calcium-Binding Protein A4; D009418:S100 Proteins; C499413:S100A4 protein, Bos taurus; C470944:S100a4 protein, mouse; C499412:S100a4 protein, rat