Type IV collagens regulate BMP signalling in Drosophila (Nature, 2008, 455:72-77)

報告日期: 2008/11/04
報告時間: 17:05/17:55
報告學生: 張玲華
講評老師: 沈孟儒
附件下載:

http://basicmed.med.ncku.edu.tw/admin/up_img/971114-3.pdf

Type IV collagens regulate BMP signaling in Drosophila

Nature. 2008 Sep 4;455(7209):72-7

 

Speaker: Ling-Hua Chang (張玲華)

Commentator: Meng-Ru Shen, MD & PhD (Dr.沈孟儒)

Date: 2008/11/04 17:00-18:00

Place: Room602

 

Abstract:

   BMP is a secreted protein which functions as patterning in different tissues and organs and signaling of BMP has been associated with several human diseases, including skeletal disorders, vascular diseases and cancer. Author investigates gradient formation by using the model of Drosophila. In the past, most scientists believe that there are two ways to create a morphogen gradient. One way is to localize production of inducer that diffuses away from its source; another way is to use an inhibitor that diffuses away from its source and blocks the action of a distributed inducer. However, how morphogens correct and restrict themselves at the right place is not very clear. One possible explanation is this could be resulted from Dpp is immobilized by an extracellular matrix protein. Author found that Dpp can interact with type IV collagen (the main component of ECM) and enhance Dpp downstream signaling in the early embryo and gastrulating. Besides, collagen type IV restricts Dpp signaling range in the ovary and influences the numbers of GSC. Finally they purposed a model to explain interaction between Dpp and collagen IV. The formation of complex of Dpp/Scw-Sog-Tsg is an essential step in Dpp/Scw gradient formation. Cleavage of this complex by Tolloid releases Dpp/scw which can rebind type IV collagen and then promote interaction of Dpp/Scw to receptor. When both Sog and Tsg exist, Dpp/Scw can release from type IV collagen and decrease signaling of Dpp. Finally, the extracellular component such as collagen or heparin suphate proteoglycans plays an important role to regulate the movement of Dpp by dedicating protein-protein interaction. And these factors regulate BMP signaling on a fine scale.

 

 

Referance:

1.   Barkai N. et al., Robustness of the BMP morphogen gradient in Drosophila embryonic patterning. Nature. 419, 304-308 (2002) 

2.   Khoshnoodi, J et al., Molecular Recognition in the Assembly of Collagens: Terminal Noncollagenous Domains Are Key Recognition Modules in the Formation of Triple Helical Protomers. J. Biol. Chem. 281, 38117–38121 (2006)