2001 Fiscal Year Final Research Report Summary
Segmentation in Vertebrates
| Project/Area Number |
10680688
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (C)
|
| Allocation Type | Single-year Grants |
|---|
| Section | 一般 |
|---|
| Research Field |
Developmental biology
|
|---|
| Research Institution | NARA INSTITUTE OF SCIENCE AND TECHNOLOGY |
|---|
Principal Investigator |
TAKAHASHI Yoshiko NARA INSTITUTE OF SCIENCE AND TECHNOLOGY, GRADUATE SCHOOL OF BIOLOGICAL SCIENCES, ASSOCIATE PROFESSOR, バイオサイエンス研究科, 助教授 (10183857)
|
|---|
| Project Period (FY) |
1998 – 2001
|
| Keywords | Embryogenesis / morphogenesis / mesoderm / ectoderm / endoderm / BMP4 / segmentation / lateral plate |
|---|
| Research Abstract |
During early development in vertebrates, the mesoderm plays a central role in specification and: establishment of the body patterning. We aimed at understanding the mechanisms by which the mesoderm specification is regulated by mainly focusing on three major topics : 1) Subdivision of the mesoderm along the dorso-ventral: axis of the body, 2) Binary decision of the lateral plate, 3) Somite segmentation along the antero-posterior axis of the body.
1) The mesoderm is subdivided into the dorsal (somite) and ventral (lateral plate) regions, We found that different concentrations of BMP4, a signalling molecule belonging to TGFb family, determine these distinct mesodermal types.
2) The lateral plate mesoderm is subdivided into two distinct layers, somatopleure and splanchnopleure., The former one contributes to the outer body underlying the skin and the latter one to the inner mesoderm surrounding the"gut organ. We found that the somatopleure is specified by its overlying; ectoderm whereas the splanchnopleure is influenced by the adjacent endoderm.
3) Most of the antero-posteriorly reiterated structures such as back bones and ribs are attributed to the somite segmentation at earlier stages in development. A pair of somites pinches off from the unsegmented somite successively along the antero-posterior axis, thus the segmentation proceeds from head to tail. We found that at the next segmentation site a microinductive event between the adjacent cells takes place leading, to a morphological boundary. Particularly, the posteriorly positioned cells to the boundary play primary roles in instructing their anterior cells to make a boundary. We designated this activity as a "segmenter".
Our novel knowledge concerning the mesodermal subdivision will open a way to understand how a simple structure gives rise to more complex organization during early development.
|
Research Products
(15 results)
