| Project/Area Number |
05680549
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| Research Category |
Grant-in-Aid for General Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Research Field |
Functional biochemistry
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| Research Institution | Yokohama City University |
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Principal Investigator |
YAMADA Michiyuki Yokohama City University Liberal Art and Science Professor, 文理学部, 教授 (10076995)
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| Co-Investigator(Kenkyū-buntansha) |
YAMADA Michiyuki Yokohama City University Liberal Art and Science Professor (10076995)
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| Project Period (FY) |
1993 – 1994
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| Project Status |
Completed (Fiscal Year 1994)
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| Budget Amount *help |
¥1,900,000 (Direct Cost: ¥1,900,000)
Fiscal Year 1994: ¥900,000 (Direct Cost: ¥900,000)
Fiscal Year 1993: ¥1,000,000 (Direct Cost: ¥1,000,000)
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| Keywords | Granulocytes / Gene expression / Retinoic acid / Myeloperoxidase / Leukemia cells / Differentiation / cis-elements / シス-エレメント |
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| Research Abstract |
All trans retinoic acid (RA) is very effective for curing patients with acute promyelocytic leukemia. The therapeutic effect was due to RA-induced differentiation of the leukemic cells. The mechanism is not yet known. The gene expression of myeloperoxidase (MPO) is limited to this type of leukemic cells and to a promyelocyte during normal granulocyte development. Human leukemic cells, HL-60 and SKM-1, express the MPO gene. When the cells were treated with RA or 1alpha, 25 (OH) vitamin D3 (D3), the cells stopped the expression. In this work we studied the transcriptional cis-acting elements of the MPO gene and the RA-and D3-induced cessation of the gene expression.
The CAT gene expression dependent on MPO genomic DNA fragments showed that two transcriptional cis-elements with an enhancer activity were located on introns 7 and 9 of the MPO gene. Methylation interference experiment showed that the intron 7 element was a consensus sequence of an estrogen response element. DNase I footprint analysis showed that the intron 9 element was 39 bp long and contained a palindromic sequence consisting of the conserved half motif of an estrogen response element with 5-bp spacing.
Next we studied the effects of RA and D3 on the MPO gene expression of SKM-1 cells. A low concentration of RA or D3 alone did not affect the gene expression, but both together suppressed the expression. These results suggested that RA and D3 might act on the gene through a common factor.
To clarify the molecular mechanism of the gene expession, studeis on transcriptional trans-acting factors are required. Cloning of a DNA binding protein cDNA is in progress.
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