| Project/Area Number |
10680626
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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 | The University of Tokyo |
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Principal Investigator |
TOYOSHIMA Yoko The University of Tokyo, Graduate School of Arts and Sciences, Associate Professor, 大学院・総合文化研究科, 助教授 (40158043)
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| Co-Investigator(Kenkyū-buntansha) |
EDAMATSU Masaki The University of Tokyo, Graduate School of Arts and Sciences, Research Associate, 大学院・総合文化研究科, 助手 (60251328)
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| Project Period (FY) |
1998 – 1999
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| Project Status |
Completed (Fiscal Year 1999)
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| Budget Amount *help |
¥3,500,000 (Direct Cost: ¥3,500,000)
Fiscal Year 1999: ¥1,000,000 (Direct Cost: ¥1,000,000)
Fiscal Year 1998: ¥2,500,000 (Direct Cost: ¥2,500,000)
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| Keywords | kinesin / ncd / kid / microtubule / processivity / optical tweezers / キメラタンパク質 |
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| Research Abstract |
Kinesin, a motor protein for microtubules, can move on a microtubule processively more than I um. This is explained by a model that the each heads of a double-headed kinesin molecule can interact with a microtubule alternately. In that case, there must be some coordination between each heads, and it is important to investigate the origin of processivity of the movement to know the molecular mechanism of motor proteins. In this study, we measured the processivity of kinesin, several kinesin-1ike proteins, and chimera proteins between them in a nanometer detecting in vitro system using optical tweezers.
Kinesin dimers, kinesin monomers, ncd dimers, and kid monomers were expressed in E. coli and then purified. These proteins were bound to microbeads via biotin-avidin system and the fractions of beads which show the binding to a microtubule in the absence of ATP and the fractions of beads which show the movement on a microtubule more than 20 nm were scored. The results showed that a single molecule of ncd and kid cannot move more than 20 nm. We further examined the motility of chimera proteins between kinesin and kid, and found that a single molecule of the chimera protein which has kinesin head can move processively, but a single molecule of the chimera protein which has double-headed kid via kinesin neck cannot move processively. These results suggest that the coordination between two kinesin heads via kinesin neck is not essential for processivity.
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