| Project/Area Number |
11102007
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| Research Category |
Grant-in-Aid for Specially Promoted Research
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| Allocation Type | Single-year Grants |
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| Review Section |
Biological Sciences
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| Research Institution | OSAKA BIOSCIENCE INSTITUTE |
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Principal Investigator |
HANAFUSA Hidesaburo Osaka Biosience institute, Director, 所長 (50312228)
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| Co-Investigator(Kenkyū-buntansha) |
IWAHARA Toshinori Osaka Biosience institute, Dept. of Molecuar Oncology, Research Associate, 分子腫瘍学部門, 研究員 (80332229)
ISHIMARU Satoshi Osaka Biosience institute, Dept. of Molecuar Oncology, Research Associate, 分子腫瘍学部門, 研究員 (00203026)
宍戸 知行 (財)大阪バイオサイエンス研究所, 第1研究部, 研究員 (80321701)
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| Project Period (FY) |
1999 – 2003
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| Project Status |
Completed (Fiscal Year 2003)
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| Budget Amount *help |
¥246,400,000 (Direct Cost: ¥208,000,000、Indirect Cost: ¥38,400,000)
Fiscal Year 2003: ¥54,600,000 (Direct Cost: ¥42,000,000、Indirect Cost: ¥12,600,000)
Fiscal Year 2002: ¥54,600,000 (Direct Cost: ¥42,000,000、Indirect Cost: ¥12,600,000)
Fiscal Year 2001: ¥57,200,000 (Direct Cost: ¥44,000,000、Indirect Cost: ¥13,200,000)
Fiscal Year 2000: ¥34,000,000 (Direct Cost: ¥34,000,000)
Fiscal Year 1999: ¥46,000,000 (Direct Cost: ¥46,000,000)
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| Keywords | Crk / Pl13K / AKT / FAK / C3G / JNK / Rho / Abl / SV40l / Abl / P13K / SV40T / AK / MAPK / Cbl / Src |
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| Research Abstract |
1.Molecular analysis of the v-Crk-induced transformation
We have found that constitutive activation of the phosphatidylinositide 3-kinase (Pl3K)/AKT pathway plays a critical role in the v-Crk-induced transformation. Our data indicated that the v-Crk-induced activation of Pl3K/AKT pathway was cooperatively achieved by two distinct interactions. One is the interaction of p85 with tyrosine phosphorylated FAK promoted by the v-Crk SH2 domain, and another is the interaction of p110 with H-Ras dictated by the v-Crk SH3 domain.
2.Genetic analyses of Crk and Crk binding factors using Drosophila.
We found that RNA interference (RNAi) of Crk, C3G and mbc in larval and pupal wing imaginal discs caused the thorax closure (TC) defect showing a cleft along the dorsal midline of the thorax like as JNK/AP-1 and Dpp pathway mutants. During TC, Crk is supposed to be involved in Rac activation by making a complex with Mbc and ELMO/CED-12, a Mbc SH3 binding. We also found that both ectopic expression of domi
… More
nant-negative PVR, a Drosophila PDGFR/VEGFR homolog, and RNAi against PVR caused a TC defect.
3.Analysis of c-Crk II function in signal transduction.
We have clearly demonstrated that c-Crk II-overexpression induces transformation of NlH 3T3 cells. We also showed that the c-Crk II-overexpression induces transcriptional activation mediated by serum response element (SRE), which can be activated by various oncoproteins, and the Crk II-induced SRE activation occurred through activation of Rho small G protein.
4.Analysis of non-receptor tyrosine kinase c-Abl
We found that c-Abl kinase activity is regulated by trans-acting factors, such as c-Src and c-Crk. We also found that c-Abl deficiency promotes anchorage independence in the fibroblasts in the presence of SV40 T antigen. We also analyzed binding proteins of Mena, which genetically interact with c-Abl. We found that Abi (Abl interactor) is one of the Mena binding proteins. We demonstrated that Abi binds to both c-Abl and Mena. In the presence of Abi, Mena phosphorylation by c-Abl is greatly enhanced. These observations suggest that Abi functions as bridging c-Abl kinase to Mena.
5.Analysis of the species differences in the susceptibility to oncogene-mediated transformation.
We have demonstrated that normal human fibroblasts are more resistant than normal rodent fibroblasts to oncogenic transformation even with the ectopic expression of hTERT (human catalytic subunit of telomerase). Our results clearly indicate that a difference in telomere biology can not fully account for the species difference in transformability and that normal human cells have still undefined intrinsic mechanisms rendering them resistant to oncogenic transformation. Less
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