In fruit flies as well as in humans the Short gastrulation (Sog)/Chordin protein functions as an antagonist of the signaling of decapentaplegic (Dpp)/bone morphogenetic protein (BMP) in the extracellular space. Such antagonism inhibits Dpp/BMP signaling by blocking its binding to the receptor. Modulation of Dpp/BMP signaling is phylogenetically conserved and is a key step for the establishment ...

Tolloid proteinases are essential for tissue patterning and extracellular matrix assembly. The members of the family differ in their substrate specificity and activity, despite sharing similar domain organization. The mechanisms underlying substrate specificity and activity are complex, with variation between family members, and depend on both multimerization and substrate interaction. In addit...

A Xenopus gene whose expression can be activated by the organizer-specific homeobox genes goosecoid and Xnot2 was isolated by differential screening. The chordin gene encodes a novel protein of 941 amino acids that has a signal sequence and four Cys-rich domains. The expression of chordin starts in Spemann's organizer subsequent to that of goosecoid, and its induction by activin requires de nov...

In Xenopus, one of the properties defining Spemann's organizer is its ability to dorsalise the mesoderm. When placed ajacent to prospective lateral/ventral mesoderm (blood, mesenchyme), the organizer causes these cells to adopt a more axial/dorsal fate (muscle). It seems likely that a similar property patterns the primitive streak of higher vertebrate embryos, but this has not yet been demonstr...

We have compared the dorsoventral development of hemichordates and chordates to deduce the organization of their common ancestor, and hence to identify the evolutionary modifications of the chordate body axis after the lineages split. In the hemichordate embryo, genes encoding bone morphogenetic proteins (Bmp) 2/4 and 5/8, as well as several genes for modulators of Bmp activity, are expressed i...

background: in vitro simulation of developmental processes is an invaluable tool to shed light on the intrinsic mechanism of developmental biosystems such as central nervous system in mammals. chick somites have been used to simulate the neural differentiation of human neural progenitor cells. in the present study, we aimed to indicate whether somites have the ability to express required neural...

Rehovot 76100 ganizer, positioned on the future dorsal side of the em-Israel bryo, can be viewed as an array of distinct secreted inhibitors that pattern the embryo by antagonizing the activity of ventralizing factors (BMPs and Wnts). Studies In 1924 Hans Spemann and Hilde Mangold carried out in Xenopus have uncovered an amazing diversity of in-an experiment that revolutionized the field of dev...

Embryos and developing organs have the remarkable ability of self-regenerating after experimental manipulations. In the Xenopus blastula half-embryos can regenerate the missing part, producing identical twins. Studies on the molecular nature of Spemann's organizer have revealed that self-regulation results from the battle between two signaling centers under reciprocal transcriptional control. L...

Bone morphogenetic proteins (BMPs) are expressed during osteogenesis and their action is regulated by corresponding BMP inhibitors. Chordin (a well recognized BMP inhibitor) and BMP-2 are expressed during osteogenic differentiation of human mesenchymal stem cells. Chordin inhibition induces human mesenchymal stem cell differentiation and reduces their proliferation by increasing BMP-2 bioavaila...