| Project/Area Number |
17580037
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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 |
Plant pathology
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| Research Institution | The University of Tokyo |
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Principal Investigator |
TAMURA Katsunori The University of Tokyo, Institute of Molecular and Cellular Biosciences, Research Associate, 分子細胞生物学研究所, 助手 (90291335)
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| Project Period (FY) |
2005 – 2006
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| Project Status |
Completed (Fiscal Year 2006)
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| Budget Amount *help |
¥3,300,000 (Direct Cost: ¥3,300,000)
Fiscal Year 2006: ¥1,500,000 (Direct Cost: ¥1,500,000)
Fiscal Year 2005: ¥1,800,000 (Direct Cost: ¥1,800,000)
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| Keywords | telomerase / hypersensitive response / cell death / disease resistance / Hrp / type III secretion system / Arabidopsis / rice / サリチル酸 / Type III分泌装置 |
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| Research Abstract |
In order to understand regulatory mechanisms of hypersensitive cell death response (HR), one of the specific disease resistance reactions, I studied on function and modulation of telomerase activity (TA), which has been thought to mediate the regulation of HR. The results obtained are as follows.
1. Among various plant-pathogenic bacterium interactions, compatible interactions without eliciting HR were found to induce TA in infected plant tissues, suggesting that TA is closely associated with disease susceptibility of plants. The TA in infected Arabidopsis leaves was shown to be regulated at the transcriptional level of AtTERT the telomerase reverse transcriptase gene in this plant species. It was also shown that the BBF motif upstream of AtTERT was involved in the transcriptional control of this gene.
2. I found that the induction of TA is mediated by certain effecter(s), which are secreted through the bacterial type III secretion system, and that some known Hrp effecters including AvrRpm1 and AvrRpt2 are involved in suppression of TA. The results also showed a possibility that the regulation of TA is mediated in part through salicylic acid pathway of HR induction.
3. By analyzing telomere length and cell death of Arabidopsis suspension cells treated with telomerase inhibitor telomestatin, TA was found to be essential for maintenance of cellular viability and prevention of apoptosis-like cell death. The results also suggested that the telomere-addition activity of TA contributes to suppression of HR cell death.
4. I found that the apoptosis inhibition factor AtBI-1 in Arabidopsis functions in suppression of HR cell death and that the telomere-binding factor Ku70 functions in positive regulation of TA.
In addition, it was shown that the dihydroflavonol-4-reductase in rice contributes to cellular redox homeostasis and suppression of cell death occurred in response to biotic and abiotic stress.
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