2005 Fiscal Year Final Research Report Summary
Elucidation of roles of Cbl-family proteins in the nervous system.
| Project/Area Number |
16500237
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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 |
Neurochemistry/Neuropharmacology
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| Research Institution | The University of Tokyo |
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Principal Investigator |
TEZUKA Tohru The University of Tokyo, The Institute of Medical Science, Div.Oncology, Research Associate, 医科学研究所, 助手 (50312319)
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| Project Period (FY) |
2004 – 2005
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| Keywords | Nervous System / tyrosine phosphorylation / Neuroscience |
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| Research Abstract |
Cbl-family proteins negatively regulate signaling through activated tyrosine kinases by acting as ubiquitin ligases. We elucidated roles of Cbl-family in the nervous system mainly by analyzing mice lacking the family members. We carried out histological analyses on Cbl- and Cbl-b- single knockout mice. In addition, we performed behavioral analyses on Cbl-b knockout mice that were highly backcrossed with C57BL/6 mice. Furthermore, we established Cre-mediated conditional Cbl/Cbl-b double knockout mice in which Cre was expressed in olfactory bulb and cerebral cortex. In these mice, the profile of tyrosine-phosphorylated proteins in the brain was different compared with that in wild-type, and Cbl- or Cbl-b-single knockout mice. The result suggest that Cbl and Cbl-b have overlapping roles in the brain. Establishment of other lines of conditional Cbl/Cbl-b double knockout mice is in progress by using different Cre-transgenic mice. We also searched for substrates for Cbl-family proteins in the brain. We found that mDab1, which is crucial for laminar formation, is ubiquitinated by Cbl upon being tyrosine-phosphorylated. Accordingly, tyrosine-phosphorylated mDab1 was degraded via proteasomes. Furthermore, we found that Cbl and Cbl-b suppressed signaling through TrkA, TrkB, Alk, and ErbB-4. Especially, we showed ubiquitination of Alk and ErbB-4 by Cbl, and identified tyrosine residues on these two kinases that were critical for Cbl-mediated ubiquitination.
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Research Products
(6 results)
