Goosecoid and Mix.1 repress Brachyury expression and are required for head formation in Xenopus
| Autor: | Branko V. Latinkić, James C. Smith |
|---|---|
| Rok vydání: | 1999 |
| Předmět: |
Fetal Proteins
Brachyury Mesoderm animal structures Xenopus Xenopus Proteins Biology Xbra Gene product Mice medicine Animals Molecular Biology Homeodomain Proteins Endoderm Gene Expression Regulation Developmental 3T3 Cells biology.organism_classification Molecular biology Cell biology DNA-Binding Proteins Repressor Proteins Gastrulation Goosecoid Protein medicine.anatomical_structure embryonic structures Trans-Activators Ectopic expression MIXL1 T-Box Domain Proteins Head Transcription Factors Developmental Biology |
| Zdroj: | Development. 126:1769-1779 |
| ISSN: | 1477-9129 0950-1991 |
| DOI: | 10.1242/dev.126.8.1769 |
| Popis: | The Xenopus homologue of Brachyury, Xbra, is expressed in the presumptive mesoderm of the early gastrula. Induction of Xbra in animal pole tissue by activin occurs only in a narrow window of activin concentrations; if the level of inducer is too high, or too low, the gene is not expressed. Previously, we have suggested that the suppression of Xbra by high concentrations of activin is due to the action of genes such as goosecoid and Mix.1. Here, we examine the roles played by goosecoid and Mix.1 during normal development, first in the control of Xbra expression and then in the formation of the mesendoderm. Consistent with the model outlined above, inhibition of the function of either gene product leads to transient ectopic expression of Xbra. Such embryos later develop dorsoanterior defects and, in the case of interference with Mix.1, additional defects in heart and gut formation. Goosecoid, a transcriptional repressor, appears to act directly on transcription of Xbra. In contrast, Mix.1, which functions as a transcriptional activator, may act on Xbra indirectly, in part through activation of goosecoid. |
| Databáze: | OpenAIRE |
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