Structure and expression of osteonectin mRNA in human tissue.

Bone Research Branch, National Institute of Dental Research, National Institutes of Health, Bethesda, MD 20892.
Connective Tissue Research (Impact Factor: 1.98). 02/1990; 24(1):17-28. DOI: 10.3109/03008209009152419
Source: PubMed

ABSTRACT A cDNA encoding osteonectin was isolated from a human bone cell cDNA library and used to examine osteonectin protein structure, mRNA structure and expression in human tissue. The deduced protein sequence shows complete identity with a recently isolated placental form and extensive homology to mouse and bovine counterparts. The protein is rich in cysteine residues, which are conserved between species except for cys 194 which is only present in the bovine. In the human, osteonectin mRNA is of two sizes, 2.3 and 3.0 kb, the former being dominant in all tissues studied. Human mRNA was detected in the Ewing sarcoma and in non-bone cell and tissue sources. The potential folded structure of osteonectin mRNA was estimated, based on computer predictions, and indicates the presence of a bulge at the 5' end of the message which includes the start of translation. Southern analysis of human genomic DNA using radiolabeled osteonectin cDNA as probe demonstrates a simple banding pattern confirming earlier studies that the osteonectin gene is present in one copy per haploid human genome.

  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: The learning process acquires new dimensions and features by using e-learning technologies. The educational activity improvement in e-learning systems requires the setting up of modular learning resources, therefore an interdisciplinary approach is necessary in order to combine teaching with computer science and cognitive psychology. Thus the learning systems using the Internet become important tools in developing users’ personality and creativity. This work aims at presenting the advantages provided by the reusable learning objects and the prospects of their use in the educational process, emphasizing the researchers’ concern to bring about learning systems with modular resources.
    Procedia - Social and Behavioral Sciences 01/2011; 15:311-315. DOI:10.1016/j.sbspro.2011.03.092
  • [Show abstract] [Hide abstract]
    ABSTRACT: Urinary calcium stones are a pathological substance, and they show similarities to physiological mineralization and other pathological mineralizations. The expression of messenger (m) RNAs of osteopontin (OPN), matrix Gla protein (MGP), osteonectin (ON) and osteocalcin (OC) in bones and teeth has been described. We previously identified OPN as an important stone matrix protein. In addition, the spontaneous calcification of arteries and cartilage in mice lacking MGP was recently reported, a finding which indicates that MGP has a function as an inhibitor of mineralization. Here, we examined the mRNA expressions of OPN, MGP, ON, and OC in the kidneys of stone-forming model rats administered an oxalate precursor, ethylene glycol (EG) for up to 28 days. The Northern blotting showed that the mRNA expressions of OPN and MGP were markedly increased with the administration of EG, but their expression patterns differed. The OPN mRNA expression reached the maximal level at day 7 after the initiation of the EG treatment and showed no significant difference after 14 and 28 days, whereas the MGP mRNA expression rose gradually to day 28. The in situ hybridization demonstrated that the cell type expressing OPN mRNA was different from that expressing MGP. We suggest that OPN acts on calcification and MGP acts on suppression.
    Urological Research 07/1999; 27(4):255-261. DOI:10.1007/s002400050119 · 1.31 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: A neoplastic clonal cell line, which was prepared by 5-azacytidine treatment of a neoplastic human salivary intercalated duct cell line, was cultivated in the presence of 22-oxa-1α, 25-dihydroxyvitamin D3 and 3 mM β-glycerophosphate. Major alterations, such as expression of type 1 collagen and alkaline phosphatase as well as of human osteopontin and osteonectin, were observed in these cells with a phenotype similar to osteoblasts. In addition, formation of bone nodule was observed in the cultured cells. The tumors produced by transplantation into nude mice of the clonal cells were treated with 22-oxa-1α, 25-dihydroxyvitamin D3 and examined for tumor growth and morphology. Consequently, growth of the treated tumor was significantly suppressed. Moreover, it was found that bone formation was induced in the treated tumor, in which the tumor cells around bone formation expressed human osteopontin and osteonectin mRNA as could be detected by in situ hybridization. The above findings indicate that the emergence of osteoblast-like cells in the human salivary cancer cells occurs in the presence of 22-oxa-1α, 25-dihydroxyvitamin D3 and β-glycerophosphate.
    Cancer Letters 06/1997; DOI:10.1016/S0304-3835(97)04722-8 · 5.02 Impact Factor