| Project/Area Number |
14571951
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| Research Category |
Grant-in-Aid for Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Field |
矯正・小児・社会系歯学
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| Research Institution | HIROSHIMA UNIVERSITY |
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Principal Investigator |
MITSUHAHA Chieko Hiroshima University, Graduate School of Biomedical Sciences, Research Associate, 大学院医・歯薬学総合研究科, 助手 (10335664)
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| Co-Investigator(Kenkyū-buntansha) |
DOHI Toshihiro Hiroshima University, Graduate School of Biomedical Sciences, Professor, 大学院・医歯薬学総合研究科, 教授 (00034182)
KOZAI Katsuyuki Hiroshima University, Graduate School of Biomedical Sciences, Professor, 大学院・医歯薬学総合研究科, 教授 (10178212)
KITAYAMA Shigeo Okayama University, Graduate School of Medicine and Dentistry, Professor, 大学院・医歯学総合研究科, 教授 (80177873)
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| Project Period (FY) |
2002 – 2003
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| Project Status |
Completed (Fiscal Year 2003)
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| Budget Amount *help |
¥3,200,000 (Direct Cost: ¥3,200,000)
Fiscal Year 2003: ¥1,500,000 (Direct Cost: ¥1,500,000)
Fiscal Year 2002: ¥1,700,000 (Direct Cost: ¥1,700,000)
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| Keywords | Dopamine Transporter / Attention Deficit Hyperactivity Disorder (ADHD) / Neurotransmitter / Dopamine / Neurotransmitter Transporter / 3'-untranslated region (UTR) / VNTR polymorphism / ADHD / DAT3'UTR / DAT3'-UTR / VNTR |
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| Research Abstract |
Attention-deficit hyperactivity disorder (ADHD) is a mental illness occurred in childhood, and thought to be related to the changes in dopaminergic neural activity, especially in dopamine transporter (DAT), which is known to regulate synaptic dopamine (DA) concentration by reuptake of released DA. To explore the possible relationship between regulated expression of DAT and ADHD, we focused on 3'-untranslated region (UTR) of DAT mRNA, and investigated the role of 3'-UTR in the regulation of DAT expression and function.
Deletion of 3'-UTR near stop codon in rat DAT cDNA reduced the [3H]DA uptake activity when expressed transiently in COS-7 cell, as compared to the original 3.4 kb DAT cDNA, which includes 1.5 kb 3'-UTR.Although rat DAT does not have variable number of tandem repeat (VNTR) in its 3'-UTR, the results F Uggest the importance of 3'-UTR in DAT functional expression. We further examine the influence of VNTR on DAT by constructing the mutant rat DATs possessing the different number of this insert in combination with their functional assays. Contrary to our respects, these mutants possessed similar functional expression in COS-7 cells.
Next, we investigated the possibility of alternative splicing of DAT at 3'-region by two different ways. 3'-RACE in human substantia nigra cDNA library revealed a single amplification identical to the reported human DAT cDNA. Analyses of database indicate the possible exons downstream of 03'-UTR within 20Kb. Using primers specific to these candidate sites, screenong of the cDNA library by PCR revealed several amplicons related to DAT, however, the subsequent nested PCR failed to determine the specific amplification.
These results suggested that 3'-UTR of DAT plays an important role in the functional expression, however, its involvement differs from the case of norepinephrine transporter (NET), in which we have demonstrated that alternative splicing of NET 'at 3'-region produces functionally different isoforms.
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