Involvement of AP-2rep in morphogenesis of the axial mesoderm in Xenopus embryo.
We have previously isolated a cDNA clone coding for Xenopus AP-2rep (activator protein-2 repressor), a member of the Krüppel-like factor family, and reported its expression pattern in developing Xenopus embryos. In the present study, the physiological function of AP-2rep in the morphogenetic movements of the dorsal mesoderm and ectoderm was investigated. Embryos injected with either AP-2rep or VP16repC (a dominant-negative mutant) into the dorsal marginal zone at the 4-cell stage exhibited abnormal morphology in dorsal structures. Both AP-2rep and VP16repC also inhibited the elongation of animal cap explants treated with activin without affecting the expression of differentiation markers. Whole-mount in situ hybridization analysis revealed that expression of brachyury and Wnt11 was greatly suppressed by injection of VP16repC or AP-2rep morpholino, but expression was restored by the simultaneous injection of wild-type AP-2rep RNA. Furthermore, the morphogenetic abnormality induced by injection of VP16repC or AP-2rep morpholino was restored by simultaneous injection of brachyury or Wnt11 mRNA. These results show that AP-2rep is involved in the morphogenesis of the mesoderm at the gastrula stage, via the brachyury and/or Wnt pathways.
Saito
Yoshinari
Y
Graduate School of Science and Technology, Niigata University, Nishi-ku, Niigata, Japan.
Gotoh
Masanori
M
Ujiie
Yasutaka
Y
Izutsu
Yumi
Y
Maéno
Mitsugu
M
D028341:Activins / Q000494:pharmacology; D000818:Animals; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D004625:Embryo, Nonmammalian / Q000187:drug effects / Q000378:metabolism; D005326:Fetal Proteins / Q000235:genetics / Q000378:metabolism*; D005775:Gastrula / Q000187:drug effects / Q000378:metabolism / Q000473:pathology; D054262:Gastrulation / Q000502:physiology; D008648:Mesoderm / Q000378:metabolism; D009024:Morphogenesis / Q000187:drug effects / Q000502:physiology; D009432:Neural Crest / Q000378:metabolism; D020825:T-Box Domain Proteins / Q000235:genetics / Q000378:metabolism*; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*; D051153:Wnt Proteins / Q000235:genetics / Q000378:metabolism*; D029867:Xenopus Proteins / Q000235:genetics / Q000378:metabolism*; D014982:Xenopus laevis / Q000196:embryology* / Q000235:genetics / Q000378:metabolism; D000098908:Brachyury Protein
D028341:Activins; D004268:DNA-Binding Proteins; D005326:Fetal Proteins; D020825:T-Box Domain Proteins; D014157:Transcription Factors; D051153:Wnt Proteins; D029867:Xenopus Proteins; D000098908:Brachyury Protein; C503842:AP-2rep protein, Xenopus; C512785:wnt11b protein, Xenopus