| 1.Research Institution | University of Tsukuba | |
| 2.Research Area | Life Science | |
| 3.Research Field | Organism Constructing Mechanisms | |
| 4.Term of Project | FY1996〜FY2000 | |
| 5.Project Number | 96L00402 | |
| 6.Title of Project | Mechanisms underlying germ line development |
| Name | Institution,Department | Title of Position |
| Satoru Kobayashi | Inst. of Biological Sciences, Univ. of Tsukuba | Assistant Prof. |
8.Core Members
| Names | Institution,Department | Title of Position |
| Yumiko Saga | Cellular & Molecular Toxicology Division National Institute of Health Sciences | Project Leader |
9.Cooperating Researchers
| Names | Institution,Department | Title of Position |
| Takahiro Akiyama | College of Environmental Health Azabu University | Research Associate |
10.Summary of Research Results
|
1. In Drosophila embryos, mitochondrial large and small ribosomal RNAs transported from mitochondria to polar granules form mitochondrial ribosomes on the granules. Since these ribosomes are integrated into polysomes on the surface of polar granules, we speculate that mitochondrial ribosomes are required for translation of mRNA(s), which encodes pole cell forming factors. Our preliminary result suggests that one of the candidates for the target mRNA is germ cell-less mRNA.. 2. We show that Nanos protein inhibits the expression of somatically-transcribed gene (fushi tarazu) in pole cells by repressing Importin α2/Oho31-dependent nuclear import of its transcriptional activator. 3. We further shows that Nanos inhibits apoptosis of pole cells during their migration to the embryonic gonads. 4. We identify a novel serine/threonin kinase (STK) gene, which encodes two transcripts enriched in polar plasm and pole cells. While the shorter transcript is observed only in pole cells, the longer one is additionally detectable in somatic cells. The longer transcript encodes STK, but the shorter one encodes a truncated form of STK lacking kinase domain. Based on these results, we speculate that the truncated STK act as a dominant-negative repressor for STK function in pole cells. |
11.Key Words
(1)Germ cells、(2)Mitochondria、(3)Drosophila
(4)mouse、(5)germ line determinant
12.References
| Author | Title of Article | |||
| T. Mochizuki | Expression and evolutionary conservation of Hydra nanos related genes | |||
| Journal | Volume | Year | Pages Concerned | |
| Develop. Genes and Evolution | 210 | 2000 | 591-602 | |
| Author | Title of Article | |||
| M. Kashikawa | Mitochondrial small ribosomal RNA is a component of germinal granules in xeuopus embryos | |||
| Journal | Volume | Year | Pages Concerned | |
| Mech. Dev. (in press) | ||||
| Author | Title of Article | |||
| A. Nakamura | Translational silencing mediated by Me31B, a component of the cytoplasmic RNP complex････ | |||
| Journal | Volume | Year | Pages Concerned | |
| Development (in press) | ||||