Project/Area Number |
07283102
|
Research Category |
Grant-in-Aid for Scientific Research on Priority Areas
|
Allocation Type | Single-year Grants |
Research Institution | University of Tokyo |
Principal Investigator |
YAMAMOTO Masayuki Graduate School of Science, Professor, 大学院・理学系研究科, 教授 (40114706)
|
Co-Investigator(Kenkyū-buntansha) |
NISHIDA Eisuke Kyoto University, Graduate School of Science, Professor, 大学院・理学研究科, 教授 (60143369)
KISHIMOTO Takeo Faculty of Biosciences, Tokyo Institute of Technology, Professor, 生命理工学部, 教授 (00124222)
SAGATA Noriyuki Kyushu University, Graduate School of Science, Professor, 大学院・理学研究科, 教授 (80142024)
OGAWA Tomoko National Institute of Genetics, Department of Cell Genetics Professor, 細胞遺伝研究系, 教授 (80028208)
MATSUMOTO Kunihiko Nagoya University, Graduate School of Science, Professor, 大学院・理学研究科, 教授 (70116375)
飯野 雄一 東京大学, 遺伝子実験施設, 助教授 (40192471)
|
Project Period (FY) |
1995 – 1998
|
Project Status |
Completed (Fiscal Year 1998)
|
Budget Amount *help |
¥310,200,000 (Direct Cost: ¥310,200,000)
Fiscal Year 1998: ¥62,000,000 (Direct Cost: ¥62,000,000)
Fiscal Year 1997: ¥62,700,000 (Direct Cost: ¥62,700,000)
Fiscal Year 1996: ¥76,000,000 (Direct Cost: ¥76,000,000)
Fiscal Year 1995: ¥109,500,000 (Direct Cost: ¥109,500,000)
|
Keywords | meiosis / fission yeast / budding yeast / neinatode / Xenopus / oocye maturarion / Mos / RNA / ヒトデ / MAPキナーゼ / meiRNA / 微小管結合蛋白質 / MPF / RNA結合蛋白質 / 細胞分裂周期 / 無細胞系 / cdc2キナーゼ |
Research Abstract |
Major results obtained in this research project are following : 1. In fission yeast, dephosphorylation of the key meiotic regulator Mei2 commits cells to meiosis. Mei2 is an RNA-binding protein, and cooperates with meiRNA to promote the first meiotic division. The essential role of meiRNA for meiosis is to assist transport of Mei2 from cytoplasm to nucleus. 2. Precise analysis of Xenopus oocyte maturation has led to three conclusions which decline previous suppositions. (1) A decrease in the activity of PKA is not mandatory for the onset of oocyte maturation. (2) cdc2 kinase is not involved in activation of the CSF activity of Mos. (3) The content of nuclei influences progression of oocyte maturation. 3. A homologue of Mos has been cloned from starfish, indicating that Mos is not restricted to vertebrates, in which oocytes arrest at the second meiotic division during maturation. This suggests that a general function of Mos is to suppress an outbreak of mitotic cell cycle progression after the first meiotic division. 4. A nuclear export signal (NES) has been found in cyclin B, which regulates meiotic M phase. Nuclear export of cyclin B is thought to be important for the DNA-damage checkpoint control. 5. In budding yeast, proteins Mrel 1, Rad50 and Xrs2 are required for two steps in meiotic recombination, i.e., they are involved in the formation of a double strand break at the recombination hot spot and in the subsequent digestion of the generated termini. Interestingly, these proteins form different complexes to fulfill each of these two functions. 6. In nematode, the daz-1 gene encoding an RNA-binding protein has been found to be essential for meiotic progression in oogenesis but not in spermatogenesis. Worms defective in daz-1 arrest female meiosis at the pachytene.
|