title: Latexin is involved in bone morphogenetic protein-2-induced chondrocyte differentiation.
abstract: Latexin is the only known carboxypeptidase A inhibitor in mammals. We previously demonstrated that BMP-2 significantly induced latexin expression in Runx2-deficient mesenchymal cells (RD-C6 cells), during chondrocyte and osteoblast differentiation. In this study, we investigated latexin expression in the skeleton and its role in chondrocyte differentiation. Immunohistochemical studies revealed that proliferating and prehypertrophic chondrocytes expressed latexin during skeletogenesis and bone fracture repair. In the early phase of bone fracture, latexin mRNA expression was dramatically upregulated. BMP-2 upregulated the expression of the mRNAs of latexin, Col2a1, and the gene encoding aggrecan (Agc1) in a micromass culture of C3H10T1/2 cells. Overexpression of latexin additively stimulated the BMP-2-induced expression of the mRNAs of Col2a, Agc1, and Col10a1. BMP-2 treatment upregulated Sox9 expression, and Sox9 stimulated the promoter activity of latexin. These results indicate that latexin is involved in BMP-2-induced chondrocyte differentiation and plays an important role in skeletogenesis and skeletal regeneration.
authors.affiliation: Department of Orthopedic Surgery, Jichi Medical University, Shimotsuke, Tochigi, Japan.
authors.forename: Ichiro
authors.initials: I
authors.lastname: Kadouchi
authors.forename: Kei
authors.initials: K
authors.lastname: Sakamoto
authors.forename: Liu
authors.initials: L
authors.lastname: Tangjiao
authors.forename: Takashi
authors.initials: T
authors.lastname: Murakami
authors.forename: Eiji
authors.initials: E
authors.lastname: Kobayashi
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Hoshino
authors.forename: Akira
authors.initials: A
authors.lastname: Yamaguchi
mesh_terms: D053674:Aggrecans / Q000235:genetics / Q000378:metabolism; D000818:Animals; D000941:Antigens / Q000235:genetics / Q000378:metabolism*; D055396:Bone Morphogenetic Protein 2 / Q000494:pharmacology; D001861:Bone Regeneration / Q000235:genetics; D002454:Cell Differentiation / Q000235:genetics; D002460:Cell Line; D019902:Chondrocytes / Q000166:cytology* / Q000187:drug effects / Q000378:metabolism; D024043:Collagen Type II / Q000235:genetics / Q000378:metabolism; D024121:Collagen Type X / Q000235:genetics / Q000378:metabolism; D004622:Embryo, Mammalian / Q000378:metabolism; D018507:Gene Expression Regulation, Developmental; D051379:Mice; D008815:Mice, Inbred Strains; D010012:Osteogenesis / Q000235:genetics; D011401:Promoter Regions, Genetic; D055758:SOX9 Transcription Factor / Q000235:genetics / Q000378:metabolism; D012863:Skeleton
chemical_list: C508320:Acan protein, mouse; D053674:Aggrecans; D000941:Antigens; C525719:Bmp2 protein, mouse; D055396:Bone Morphogenetic Protein 2; C447413:Col2a1 protein, mouse; D024043:Collagen Type II; D024121:Collagen Type X; C086812:Lxn protein, rat; D055758:SOX9 Transcription Factor; C527933:Sox9 protein, mouse