Analysis of mouse Evx genes: Evx-1 displays graded expression in the primitive streak
Autor: | Michael K. Dush, Gail R. Martin |
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Rok vydání: | 1992 |
Předmět: |
Mesoderm
Molecular Sequence Data Ectoderm Biology Mice Gene expression medicine Animals Amino Acid Sequence Molecular Biology Homeodomain Proteins Genetics Base Sequence Primitive streak Embryogenesis Genes Homeobox Chromosome Mapping Gastrula Cell Biology Cell biology DNA-Binding Proteins Gastrulation medicine.anatomical_structure Gene Expression Regulation Epiblast embryonic structures DNA Probes NODAL Sequence Alignment Developmental Biology |
Zdroj: | Developmental Biology. 151:273-287 |
ISSN: | 0012-1606 |
DOI: | 10.1016/0012-1606(92)90232-6 |
Popis: | Two mouse genes, Evx-1 and Evx-2 , each encoding a homeodomain closely related to that of the Drosophila evenskipped gene were isolated using a PCR-based strategy. The structure and sequence of these genes are described. Mapping studies localized Evx-1 to chromosome 6, near the Hox-1 gene cluster, and Evx-2 to chromosome 2, near the Hox-4 cluster. The evolutionary implications of these linkages are discussed. RNA in situ hybridization analysis of Evx expression in embryos demonstrated a striking pattern of Evx-1 expression during gastrulation, whereas Evx-2 RNA could not be detected at any stage by this technique. Evx-1 RNA is first detected shortly before the onset of gastrulation in a region of ectoderm containing cells that will soon be found in the primitive streak. This localized expression of Evx-1 provides the first molecular evidence for regional differences in the mouse embryonic ectoderm before gastrulation. Throughout gastrulation, Evx-1 expression is limited to cells near and within the streak and that expression is graded, with a posterior-to-anterior decrease in the level of RNA. Based on fate-mapping studies indicating that different types of mesoderm emerge from different regions of the primitive streak and our observation that high levels of expression are localized to the region that will give rise to extraembryonic and ventral mesoderm, we speculate that Evx-1 plays a role in the dorsoventral specification of mesodermal cell fate. |
Databáze: | OpenAIRE |
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