Comparative study of sequential expression of the organizer-related genes in normal Cynops pyrrhogaster embryos and mesodermalized ectoderm.
An artificially mesodermalized ectoderm (mE) of early Cynops pyrrhogaster gastrula acquires the organizer property; the mE is able to induce the secondary axis. The expression of organizer-related genes was investigated during the mesodermalizing process of the mE. The expression of C. pyrrhogaster organizer-related genes, such as bra, gsc, lim-1, chd and noggin, were analyzed. Cynops pyrrhogaster shh expression was also investigated. The organizer-related genes were activated by 12 h after the mesoderm-inducing stimulus. It was noted that there was a temporal gap in the expression of each gene. The expression of bra and gsc seemed to be more quickly activated during the mesodermalizing process. While expression of lim-1 and noggin was activated later than that of bra and gsc, lim-1 expression was earlier than chd and noggin expression. Shh expression was activated later than lim-1/noggin. The present study suggests the possibility that the bra/gsc, lim-1, chd, noggin and shh genes are expressed one by one in that order during the mesodermalizing of the presumptive ectoderm. It also indicates that the sequence is not always consistent with that of the whole embryo during normal embryogenesis. The meaning of the discrepancy will be discussed in connection with the cascade of certain genes expressed during the mesodermalizing process.
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Natural Enviromental Science, Department of Enviromental Science, Graduate School of Science and Technology, Kumamoto University, Kumamoto 860-8555, Japan.
Sakaguchi
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K
Tajima
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Suzuki
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AS
D000199:Actins / Q000235:genetics / Q000378:metabolism; D000400:Air Sacs; D000595:Amino Acid Sequence; D000818:Animals; D002347:Carps; D002352:Carrier Proteins; D004475:Ectoderm / Q000502:physiology*; D005326:Fetal Proteins; D005775:Gastrula / Q000502:physiology*; D018507:Gene Expression Regulation, Developmental; D006023:Glycoproteins; D051956:Goosecoid Protein; D053823:Hedgehog Proteins; D018398:Homeodomain Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D006801:Humans; D036341:Intercellular Signaling Peptides and Proteins; D060850:LIM-Homeodomain Proteins; D008648:Mesoderm / Q000502:physiology*; D008969:Molecular Sequence Data; D020897:Organizers, Embryonic / Q000502:physiology*; D016133:Polymerase Chain Reaction / Q000379:methods; D011506:Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D012097:Repressor Proteins; D012455:Salamandridae / Q000196:embryology* / Q000235:genetics; D016415:Sequence Alignment; D020825:T-Box Domain Proteins / Q000235:genetics / Q000378:metabolism; D013997:Time Factors; D015534:Trans-Activators / Q000235:genetics / Q000378:metabolism; D014157:Transcription Factors; D000098908:Brachyury Protein; D000099176:Noggin Protein
D000199:Actins; D002352:Carrier Proteins; D005326:Fetal Proteins; D006023:Glycoproteins; D051956:Goosecoid Protein; D053823:Hedgehog Proteins; D018398:Homeodomain Proteins; D036341:Intercellular Signaling Peptides and Proteins; D060850:LIM-Homeodomain Proteins; D011506:Proteins; D012097:Repressor Proteins; D020825:T-Box Domain Proteins; D015534:Trans-Activators; D014157:Transcription Factors; D000098908:Brachyury Protein; D000099176:Noggin Protein; C085473:LHX1 protein, human; C509239:SHH protein, human; C054234:chordin