Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.6.3.14 (ATP synthase)
 7,042 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Among several bioactive substances known as coupling factors, transforming growth factor-beta (TGF-beta), interleukin-1 (IL-1), and prostaglandin (PG) E1 and E2 increased not only the activity of alkaline phosphatase but also the rate of incorporation of 45Ca2+ into ROS 17/2.8 during a 3-day culture: the former two factors are known to be formed at the site where bone is resorbed, while PG's are known as one of the factors involved in bone resorption. Parathyroid hormone, another hormone that affects bone metabolism, elevated the incorporation of 45Ca2+ by and decreased the alkaline phosphatase activity of the cells. The facts indicate the possibility that the osteoblastic cells are involved in the transport of calcium ions when bones are being resorbed. On the other hand, when these osteosarcoma cells were cultured in DMEM containing ascorbate and beta-glycerophosphate, followed by staining with silver nitrate by the procedure of von Kossa, there appeared many groups of cells that were positively stained as dark brown spots. Cells were then cultured under the same conditions in the presence of radioactive calcium, and the radioactivity accumulated was measured. The result showed that the presence of both ascorbate and beta-glycerophosphate in the culture medium dramatically increased the accumulation of 45Ca2+. It appears from these facts that ROS 17/2.8 cells are capable of incorporating and/or accumulating calcium ion if they are cultured under appropriate conditions. These cells will probably be able to produce a calcified matrix in vitro.
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PMID:[Effects of L-ascorbic acid and bone metabolism factors on alkaline phosphatase activity of and 45Ca2+ incorporation by ROS 17/2.8 cells]. 213 81

The effects of interleukin 1, transforming growth factor-beta (coupling factors), prostaglandin E1, and prostaglandin E2 on incorporation of 45Ca2+ and on alkaline phosphatase activity were studied using cultured ROS 17/2.8 cells, one of cell lines derived from rat osteosarcoma. We found that all these factors stimulate both the incorporation of 45Ca2+ and alkaline phosphatase activity of these cells. On the other hand, one of the bone resorption hormones, parathyroid hormone (PTH), suppressed the proliferation of cells and decreased the alkaline phosphatase activity at considerably low concentrations (1 X 10(-12)-1 X 10(-11) M). However, the hormone stimulated the incorporation of 45Ca2+ by these cells in a dose-dependent manner; the maximum stimulation on day 3 was observed at 1 X 10(-7) M and it was approximately 3 times the control value. The data suggest therefore, that the osteoblasts incorporated calcium ions and transported them while bone resorption was occurring. Thus the ROS 17/2.8 cell line appears to be an advantageous experimental system for the study of calcium metabolism of osteoblasts in vitro.
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PMID:[Effects of various factors involved in bone metabolism on 45Ca2+ incorporation and alkaline phosphatase activity of ROS 17/2.8 cells]. 260 4

In this study, our goal was to identify genes whose expression in liver is altered in female F-344 rats during mitosuppression induced by 42 days of ethinyl estradiol (EE) treatment (Yager et al., Carcinogenesis, 15, 2117-2123, 1994). Northern analysis demonstrated that the mRNA levels for transforming growth factor-beta1 (TGF-beta1) and the mannose 6-phosphate/insulin-like growth factor II receptor were significantly increased by EE treatment. Ten cDNA clones representing mRNAs whose expression was increased two- to four-fold in the mitosuppressed livers were identified by differential display. Sequence analysis revealed that one was homologous to the S-24 ribosomal protein and another to mitochondrial ATPase subunit e. The remaining clones showed no homology to known genes in GenBank. However, the expression of clones 15, 16 and 17 was increased in HepG2 cells following treatment with doxorubicin suggesting their induction by oxidative DNA damage. These results suggest that two independent but interrelated signalling pathways, one mediated through transforming growth factor-beta and the other through oxidative DNA damage, may contribute to hepatic mitosuppression caused by EE, perhaps through activation of cyclin-dependent kinase inhibitors.
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PMID:Identification of genes whose expression is altered during mitosuppression in livers of ethinyl estradiol-treated female rats. 900 20