| Project/Area Number |
17570134
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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 |
Biophysics
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| Research Institution | KYUSHU UNIVERCITY |
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Principal Investigator |
MATSUMOTO Akira Kyushu University, Center for Research and Advancement in Higher Education, 高等教育開発推進センター, 助手 (40229539)
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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 |
¥3,600,000 (Direct Cost: ¥3,600,000)
Fiscal Year 2006: ¥900,000 (Direct Cost: ¥900,000)
Fiscal Year 2005: ¥2,700,000 (Direct Cost: ¥2,700,000)
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| Keywords | circadian rhythm / culture cell / Drosophila / reconstruction / gene network |
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| Research Abstract |
Gene-protein networks composed of artificial chimeric genes were reconstructed by "molecular LEGO" method in Drosophila S2 cell. A double feedback loop mimicking Drosophila circadian system showed a relatively stable oscillation with 4-6 hrs in period. Parameters which significantly influences to stability and period of the oscillation were analyzed with the altered components having mutation in each domain. The half life of mRNA of a negative loop component, hereafter called as a negative factor, drastically affects to a stability of oscillation. When the half-life becomes shorter, the rhythmicity becomes more stable. However, any significant change in period was not found by changing the half-life of mRNA in a negative factor. The protein degradation of a negative factor in the range from 2 to 16 hrs in its half-life had no effect on either stability or period of the oscillation. When the protein half-life of a negative factor was similar to that of a positive one, the oscillation becomes stable. The nuclear localization of negative factor was found as an important parameter to generate a periodicity because its efficiency changed the period of the reconstructing rhythm. Moreover, the less efficiency of nuclear localization of a negative factor induced no rhythmicity. The ratio between negative and positive factor is also important. A given period lengthened when the ratio is 1:5 or 5:1 as compared to when they were even. Surprisingly, the reconstructing oscillation showed a temperature-compensation in its period in the range between 20 and 25 C.
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