Ubiquitous MyoD transcription at the midblastula transition precedes induction-dependent MyoD expression in presumptive mesoderm of X. laevis.
We have used a quantitative reverse transcription-polymerase chain reaction assay to detect MyoD mRNA during early embryonic development of Xenopus laevis. We find that during a short period of time following the midblastula transition MyoD becomes transcriptionally activated at a low level ubiquitously throughout the embryo. Restriction of MyoD expression to muscle precursor cells appears as a subsequent event, in which the process of mesoderm induction stabilizes transcription only in the marginal zone of the embryo, the presumptive mesoderm.
Rupp
R A
RA
Department of Genetics, Fred Hutchinson Cancer Research Center, Seattle, Washington 98104.
Weintraub
H
H
D000818:Animals; D001483:Base Sequence; D015152:Blotting, Northern; D004268:DNA-Binding Proteins / Q000235:genetics; D004627:Embryonic Induction; D015870:Gene Expression; D005801:Genes, Homeobox; D008648:Mesoderm / Q000502:physiology; D008969:Molecular Sequence Data; D009124:Muscle Proteins / Q000235:genetics*; D017570:MyoD Protein; D009841:Oligonucleotides / Q000737:chemistry; D016133:Polymerase Chain Reaction; D012333:RNA, Messenger / Q000235:genetics; D014158:Transcription, Genetic; D014982:Xenopus laevis / Q000196:embryology*
D004268:DNA-Binding Proteins; D009124:Muscle Proteins; D017570:MyoD Protein; D009841:Oligonucleotides; D012333:RNA, Messenger