Project/Area Number |
11837001
|
Research Category |
Grant-in-Aid for Scientific Research (C)
|
Allocation Type | Single-year Grants |
Section | 一般 |
Research Institution | HOKKAIDO UNIVERSITY |
Principal Investigator |
UEDA Tetsuo (2000) Hokkaido Univ.Res.Inst.for Electronic Sci., Prof., 電子科学研究所, 教授 (20113524)
西山 宣昭 (1999) 北海道大学, 電子科学研究所, 助教授 (10198525)
|
Co-Investigator(Kenkyū-buntansha) |
YAMADA Hiroyasu Hokkaido Univ.Res.Inst.for Electronic Sci., A part time research worker, 電子科学研究所, 非常勤研究員 (70291937)
上田 哲男 北海道大学, 電子科学研究所, 教授 (20113524)
|
Project Period (FY) |
1999 – 2000
|
Project Status |
Completed (Fiscal Year 2000)
|
Budget Amount *help |
¥3,500,000 (Direct Cost: ¥3,500,000)
Fiscal Year 2000: ¥900,000 (Direct Cost: ¥900,000)
Fiscal Year 1999: ¥2,600,000 (Direct Cost: ¥2,600,000)
|
Keywords | True slime molds / Maze problem / motile rhythm / phytochrome / action spectra / photomorphogenesis / Physarum polycephalum / cell shape / 記憶現象 / 真正粘菌変形体 / 代謝ダイナミクス / 細胞骨格 / 結合振動子系 |
Research Abstract |
The mechanism of higher information processing in a single cellular organism is clarified in terms of nonlinear dynamics in a large amoeboid cell of the Physarum plasmodium. 1. Maze-solving : The organism develops veins in a maze in such a way that veins which located initially at dead ends in a maze disappear and those which connect entrance and exit become thick. When there are two pathways, shorter one is selected. Thus, the organism connects the shortest route from entrance to exit. 2. Coupling among vein formation and rhythmic contraction : The veins are formed along the phase gradient of the rhythmic contraction which are artificially generated by oscillating the external temperature. 3. Size control : The large amoeboid cell fragments into many pieces by exposure to low temperature or by irradiation with light. Action spectroscopy and antagonistic action of red and far red indicate that one of the photoreceptors is phytochrome. 4. Time Memory : The effects of low temperature treatment remain in such a way that the total time of exposure is kept constant.
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