Brachyury (T) expression in embryonal carcinoma P19 cells resembles its expression in primitive streak and tail-bud but not that in notochord.
Brachyury (T) is involved in mesoderm induction during early mouse development. T expression in embryonal carcinoma P19 cells, which differentiate into mesoderm derivatives in vitro, was studied. Endogenous T expression in P19 cells was transiently induced when the cells were allowed to form aggregates. This expression was enhanced by dimethyl sulfoxide. In situ hybridization showed that T expressing cells formed clusters on the aggregates. Transfection of plasmids encoding reporter genes under the control of the upstream region of T showed that the sequence up to -351 bp can resemble the differentiation-dependent expression of T in P19 cells. To define the promoter region regulating T expression, transgenic mice carrying LacZ under the control of the upstream region were prepared. The region up to -351 bp is sufficient to direct the expression in the primitive streak and tail-bud. The upstream region up to -2400 bp does not support expression in the notochord. The sequence between -987 and -585 bp enhances expression in the primitive streak and tail-bud. In the tail-bud where new cells for elongation of the anteroposterior axis were continuously supplied, the sequence up to -987 bp drove lacZ expression in gut endoderm and prospective neuroectoderm as well as in mesoderm derivatives.
Graduate Program for Biochemical Regulation, Graduate School of Agricultural Sciences, Nagoya, Japan.
H
H
Yamaguchi
T
T
Niimi
Y
Y
Kitagawa
K
K
Miki
D000818:Animals; D001483:Base Sequence; D018236:Carcinoma, Embryonal / Q000235:genetics* / Q000473:pathology; D017931:DNA Primers; D004268:DNA-Binding Proteins / Q000235:genetics*; D005326:Fetal Proteins; D018507:Gene Expression Regulation, Developmental; D051379:Mice; D008822:Mice, Transgenic; D009672:Notochord / Q000196:embryology*; D011401:Promoter Regions, Genetic; D020825:T-Box Domain Proteins; D013623:Tail / Q000196:embryology*; D014157:Transcription Factors / Q000235:genetics*; D000098908:Brachyury Protein
D017931:DNA Primers; D004268:DNA-Binding Proteins; D005326:Fetal Proteins; D020825:T-Box Domain Proteins; D014157:Transcription Factors; D000098908:Brachyury Protein