| Project/Area Number |
09680718
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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 |
Developmental biology
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| Research Institution | Tohoku University |
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Principal Investigator |
OHSUGI Kojune Tohoku Univ., Graduate School of Science, Dept.of Biology, Research Assistant, 大学院・理学研究科, 助手 (00201377)
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| Co-Investigator(Kenkyū-buntansha) |
TAMURA Koji Tohoku Univ., Graduate School of Science, Dept.of Biology, Research Assistant, 大学院・理学研究科, 助手 (70261550)
YAMAMOTO Hiroaki Tohoku Univ., Graduate School of Science, Dept.of Biology, Associate Professor, 大学院・理学研究科, 助教授 (40174809)
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| Project Period (FY) |
1997 – 1998
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| Project Status |
Completed (Fiscal Year 1998)
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| Budget Amount *help |
¥3,800,000 (Direct Cost: ¥3,800,000)
Fiscal Year 1998: ¥900,000 (Direct Cost: ¥900,000)
Fiscal Year 1997: ¥2,900,000 (Direct Cost: ¥2,900,000)
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| Keywords | Developmental Biology / morphogenesis / pattern formation / Cell cycle / Limb / Cell growth |
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| Research Abstract |
We have shown previously that when anterior cell cycles are lengthened by Aphidicolin beads during chick limb development, expression of some genes characteristic of the posteriorregion (BMP-2, Hoxdll and Fgf4) is induced, and the extra digit formation is also induced.
In this study, we showed that these inductions are not related to the occurrence of ectopic cell death, and this further supports that cell cycle length could affect limb pattern formation by influencing gene expression in a particular region of limb buds. This raised the possibility that there may be a regional differences in the cell cycle length during normal limb development which may correlate with patterns of gene expression. To examine this possibility, we have analyzed the spatial distribution of relative cell cycle times in limb buds of several different stages. Using BrdU incorpo-ration, we find that cell cycle lengths are not uniform, and that domains of cells with cycles that are longer than surrounding areas can be identified. One of these domains is in the posterior of the limb bud. By double staining method, we showed that this domain closely corresponds to regions of Shh and BMP-2 expression and co-localizes with the ZPA.This finding further supports the link between cell cycle length and patterns of gene expression. Furthermore, when genes which are members of Cyclin dependent kinase inhibitors (CKI), p16, p18, p19 were ectopically over-expressed in limb bud by expression vectors using a electroporation method, ectopic expression of BMP-2 was observed in cells in which p16 or p18 gene was introduced. This showed more directory that cell cycle length could control the expression of patterning genes in limb development.
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