Difference in the maternal and zygotic contributions of tumorhead on embryogenesis.
Tumorhead (TH) is a maternally expressed gene in Xenopus laevis, that when overexpressed, increased proliferation of ectodermal derivatives and inhibited neural and epidermal differentiation. However, injection of anti-TH antibodies inhibited cleavage of all blastomeres, not only those contributing to the ectoderm. The injection of TH morpholino antisense oligonucleotide (TH-MO), which inhibits translation of TH mRNA, did not affect early cleavage but inhibited cell division in both the neural field and epidermis. This was accompanied by the inhibition of neural and epidermal markers. TH-MO did not affect the formation and differentiation of mesoderm and endoderm derivatives. Our overexpression and loss-of-function studies demonstrated that TH plays an important role in differentiation of the ectoderm by regulating cell proliferation. They also supported the conclusion that the maternal component of TH may affect the cell cycle in all cells, while the zygotic component has a germ layer-specific effect on the ectoderm.
Wu
Chuan Fen
CF
Department of Molecular Genetics, The University of Texas M. D. Anderson Cancer Center, 1515 Holcombe Blvd., Houston, TX 77030, USA.
Chan
Agnes Pui-Yee
AP
Etkin
Laurence D
LD
D000818:Animals; D001483:Base Sequence; D002453:Cell Cycle; D002454:Cell Differentiation; D002455:Cell Division; D018076:DNA, Complementary / Q000235:genetics; D004475:Ectoderm / Q000166:cytology; D004817:Epidermis / Q000002:abnormalities / Q000196:embryology; D005260:Female; D018507:Gene Expression Regulation, Developmental; D009420:Nervous System / Q000196:embryology; D009421:Nervous System Malformations / Q000235:genetics; D020319:Oligodeoxyribonucleotides, Antisense / Q000494:pharmacology; D010641:Phenotype; D011506:Proteins / Q000037:antagonists & inhibitors / Q000235:genetics* / Q000378:metabolism; D029867:Xenopus Proteins; D014982:Xenopus laevis / Q000196:embryology* / Q000235:genetics* / Q000378:metabolism; D015053:Zygote / Q000378:metabolism*
D018076:DNA, Complementary; D020319:Oligodeoxyribonucleotides, Antisense; D011506:Proteins; D029867:Xenopus Proteins; C437083:trhd protein, Xenopus