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Stem cell-like Xenopus Embryonic Explants to Study Early Neural Developmental Features In Vitro and In Vivo
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The left-right axis is regulated by the interplay of Coco, Xnr1 and derrière in Xenopus embryos

Alin Vonica1, Ali H Brivanlou

  • 1The Laboratory of Vertebrate Embryology, The Rockefeller University, New York, NY 10021, USA.

Developmental Biology
|January 24, 2007
PubMed

Insights

Coco, Xnr1, and derrière form a signaling center regulating left-right axis formation in Xenopus embryos. This pathway involves TGF-beta signaling, with specific protein localization crucial for asymmetric organ patterning.

Area of Science:

  • Developmental Biology
  • Molecular Biology
  • Genetics

Background:

  • Left-right axis formation is critical for proper organ placement.
  • Transforming Growth Factor-beta (TGF-beta) signaling plays a key role in embryonic asymmetry.
  • DAN domain proteins are known regulators of TGF-beta signaling and axis determination.

Purpose of the Study:

  • To investigate the roles of Xenopus DAN family member Coco, Xnr1, and derrière in left-right axis patterning.
  • To elucidate the molecular interactions and localization requirements of these proteins in establishing embryonic asymmetry.

Main Methods:

  • Co-expression analysis of Coco, Xnr1, and derrière in Xenopus embryos.
  • Side-specific protein depletion experiments to assess functional requirements.
  • Analysis of TGF-beta signaling pathway activity in response to protein manipulation.

Main Results:

  • Coco, Xnr1, and derrière are coexpressed in the posterior paraxial mesoderm.
  • Left-right patterning requires Coco on the right side and Xnr1/derrière on the left side.
  • Coco absence leads to bilateral TGF-beta signaling, disrupting asymmetry.

Conclusions:

  • Xenopus derrière, Xnr1, and Coco constitute a post-transcriptionally regulated signaling center.
  • This center is essential for amplifying TGF-beta signaling on the left side of the embryo.
  • The precise localization of these proteins is critical for establishing the left-right axis and subsequent visceral asymmetry.

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