Distinct regulatory control of the Brachyury gene in axial and non-axial mesoderm suggests separation of mesoderm lineages early in mouse gastrulation.
Brachyury is required for the normal extension of the anteroposterior axis during mouse embryogenesis. A transgene comprising sequences from -500 to +150 relative to the start of Brachyury transcription, and the reporter gene lacZ, recapitulates some, but not all elements of Brachyury expression. Beta-Galactosidase expression is seen in the primitive streak from 6.5 d.p.c. but there is no detectable reporter expression in the node or notochord. Thus, the regulatory sequences required for the expression of Brachyury in the cells traversing the primitive streak are distinct from those required for the initiation of expression in the node. This suggests that different or additional signals are involved in activation of Brachyury in the node and notochord than those inducing Brachyury in the primitive streak. Additionally, the data suggest the possibility that axial and non-axial mesoderm are distinct from the earliest stages of Brachyury expression.
Clements
D
D
Department of Biological Sciences, University of Warwick, Coventry, UK.
Taylor
H C
HC
Herrmann
B G
BG
Stott
D
D
D000818:Animals; D001483:Base Sequence; D019070:Cell Lineage; D004268:DNA-Binding Proteins / Q000096:biosynthesis / Q000235:genetics*; D005326:Fetal Proteins / Q000096:biosynthesis / Q000235:genetics*; D005775:Gastrula / Q000166:cytology / Q000378:metabolism* / Q000648:ultrastructure; D018507:Gene Expression Regulation, Developmental; D017930:Genes, Reporter; D008648:Mesoderm / Q000145:classification / Q000378:metabolism*; D051379:Mice; D008969:Molecular Sequence Data; D009024:Morphogenesis / Q000235:genetics; D011993:Recombinant Fusion Proteins / Q000032:analysis; D020825:T-Box Domain Proteins; D019076:Transgenes; D001616:beta-Galactosidase / Q000032:analysis / Q000235:genetics; D000098908:Brachyury Protein
D004268:DNA-Binding Proteins; D005326:Fetal Proteins; D011993:Recombinant Fusion Proteins; D020825:T-Box Domain Proteins; D001616:beta-Galactosidase; D000098908:Brachyury Protein