| Project/Area Number |
04670137
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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 |
General medical chemistry
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| Research Institution | University of Tokyo |
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Principal Investigator |
NISHIMURA Tetsuji University of Tokyo, School of Medicine, Department of Biochemistry, Assistant, 医学部(医), 助手 (20156110)
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| Project Period (FY) |
1992 – 1993
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| Project Status |
Completed (Fiscal Year 1993)
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| Budget Amount *help |
¥2,100,000 (Direct Cost: ¥2,100,000)
Fiscal Year 1993: ¥800,000 (Direct Cost: ¥800,000)
Fiscal Year 1992: ¥1,300,000 (Direct Cost: ¥1,300,000)
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| Keywords | Ribosomal RNA Gene / DNA Binding Proteins / Promoter Region / CAT Assay / Transcriptional Regulation / In Vitro rRNA Synthesis / House-keeping Gene / Genetic Engineering / 核移行シグナル / 核小体 / HMG‐box |
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| Research Abstract |
It is necessary two DNA binding proteins, Upstream Binding Protein(UBF)and SL-1, for formation of the initiation complex of ribosomal RNA gene(rDNA)transcription. Mouse UBF has a nuclear localization sequence in the 4th HMG-box. Deletion of either the HMG-box1, a region crucial for rDNA binding, or the acidic tail, a region that may interasct with SL-1, results in the loss of necleolar targeting. HMG-box1 is necessary for UBF to bind to the upstream control element of the rDNA.Mouse UBF is transferred to the nucleus by its NLS and is sequestered in the nucleous by its specific and stable binding to the rDNA promoter via HMG-boxes and the acidic tail.
The region between the transcriptional initiation site and -1200nt shows the promoter activities. In this region, there are several GC-boxes and three kinds of serum response elements, but no TATA-box or CAT-box. The existence of those cis acting element is necessary for regulation of the UBF gene. The mRNA of UBF was expressed 4 times after nutritional shift-up. These observation indicates UBF gene is one of the house-keeping genes and is regulated through several kinds of element in the promoter region correspondingly with growth-stimulation signals. SL-1 is constituted with 5 kinds of proteins, containing TATA binding protein(TBP), at least. UBF binds with protein associated TBP.Ribosomal RNA synthesis in vitro is inhibited with anti-body against TBP.
So TBP binds the promoter region of rDNA.And then UBF makes a stable complex with SL-1/DNA complex as pre-initiation complex of rDNA transcription.
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