Cell and Tissue Research

, Volume 335, Issue 2, pp 357–369

Involvement of AP-2rep in morphogenesis of the axial mesoderm in Xenopus embryo

  • Yoshinari Saito
  • Masanori Gotoh
  • Yasutaka Ujiie
  • Yumi Izutsu
  • Mitsugu Maéno
Regular Article


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.


Krüppel-like factor Gastrulation morphogenesis Brachyury Wnt AP-2 Xenopus laevis (Anura) 

Supplementary material

441_2008_712_MOESM1_ESM.pdf (70 kb)
Supplement Fig. 1.Differentiation of neural, muscle, and notochord tissues occurred in AP-2rep- or VP16repC-injected embryos. Embryos were injected with AP-2rep (1000 pg) or VP16repC (100 pg) into the dorsal and ventral marginal zone regions (all the blastomeres) at the 4-cell stage and cultured until stage 39. Expression of N-CAM (a-c), muscle actin (d-f), and keratan sulfate (g-i) was analyzed by whole-mount antibody staining (arrows positive signals stained by each antibody). All the embryos injected with either AP-2rep or VP16repC show positive staining with these markers (a, n=2; b, n=5; c, n=5; d, n=2; e, n=5; f, n=5; g, n=4; h, n=5; i, n=5) (PDF 70.32 KB)


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Copyright information

© Springer-Verlag 2008

Authors and Affiliations

  • Yoshinari Saito
    • 1
  • Masanori Gotoh
    • 1
  • Yasutaka Ujiie
    • 1
  • Yumi Izutsu
    • 2
  • Mitsugu Maéno
    • 2
  1. 1.Graduate School of Science and TechnologyNiigata UniversityNiigataJapan
  2. 2.Department of Biology, Faculty of ScienceNiigata UniversityNiigataJapan

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