| Project/Area Number |
13680805
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (C)
|
| Allocation Type | Single-year Grants |
|---|
| Section | 一般 |
|---|
| Research Field |
Developmental biology
|
|---|
| Research Institution | RIKEN (The Institute of Physical and Chemical Research) |
|---|
Principal Investigator |
HIBI Masahiko RIKEN, Laboratory for Vertebrate Axis Formation, Team Leader, 体軸形成研究チーム, チームリーダー (40273627)
|
|---|
| Project Period (FY) |
2001 – 2002
|
| Project Status |
Completed (Fiscal Year 2002)
|
| Budget Amount *help |
¥3,600,000 (Direct Cost: ¥3,600,000)
Fiscal Year 2002: ¥1,700,000 (Direct Cost: ¥1,700,000)
Fiscal Year 2001: ¥1,900,000 (Direct Cost: ¥1,900,000)
|
|---|
| Keywords | axis formation / zebrafish / homeobox gene / transcriptional repressor / dorsal organizer / BMP / negative feedback / head formation / ゼブラフイツシュ / 形態形成 / 神経領域化 / 神経細胞 / ノックアウトマウス |
|---|
| Research Abstract |
In amphibian and teleost embryogenesis, the program initiating axis formation begins soon after fertilization. In these species, the dorsal determinants are believed to be initially localized to the vegetal pole, and then transported to the dorsal side of the embryo. The molecular nature of the dorsal determinants has not been elucidated. It is known that these molecules activate the canonical Wnt pathway, leading to the nuclear accumulation of β-catenin on dorsal side, which further stimulates the expression of genes involved in the dorsal organizer induction. The zebrafish homeobox gene bozozok acts downstream of the Wnt signaling pathway and is required for organizer induction. Bozozok functions as a transcriptional repressor and inhibits dorsal expression of a novel bomeobox gene ved. Ved also functions as a transcriptional repressor that represses organizer genes. We further found that ved functions redundantly with vox and vent to restrict the organizer domain. In this study, we also isolated the gene responsible for zebrafish ventralized mutant ogon by a positional cloning strategy and found that the ogon locus encodes a zebrafish homologue of Sizzled. Ogon/Sizzled functions as a negative feedback regulator of BMP signaling. In addition, we generated mice deficient in fez and fez-like, which are expressed specifically in forebarin during early embryogenesis.
|
