Skip to Content
Merck
  • Thyroid hormone-regulated Wnt5a/Ror2 signaling is essential for dedifferentiation of larval epithelial cells into adult stem cells in the Xenopus laevis intestine.

Thyroid hormone-regulated Wnt5a/Ror2 signaling is essential for dedifferentiation of larval epithelial cells into adult stem cells in the Xenopus laevis intestine.

PloS one (2014-09-12)
Atsuko Ishizuya-Oka, Mitsuko Kajita, Takashi Hasebe
ABSTRACT

Amphibian intestinal remodeling, where thyroid hormone (T3) induces some larval epithelial cells to become adult stem cells analogous to the mammalian intestinal ones, serves as a unique model for studying how the adult stem cells are formed. To clarify its molecular mechanisms, we here investigated roles of non-canonical Wnt signaling in the larval-to-adult intestinal remodeling during Xenopus laevis metamorphosis. Our quantitative RT-PCR (qRT-PCR) and immunohistochemical analyses indicated that the expressions of Wnt5a and its receptors, frizzled 2 (Fzd2) and receptor tyrosine kinase-like orphan receptor 2 (Ror2) are up-regulated by T3 and are spatiotemporally correlated with adult epithelial development in the X. laevis intestine. Notably, changes in morphology of larval absorptive epithelial cells expressing Ror2 coincide well with formation of the adult stem cells during metamorphosis. In addition, by using organ cultures of the tadpole intestine, we have experimentally shown that addition of exogenous Wnt5a protein to the culture medium causes morphological changes in the larval epithelium expressing Ror2 even in the absence of T3. In contrast, in the presence of T3 where the adult stem cells are formed in vitro, inhibition of endogenous Wnt5a by an anti-Wnt5a antibody suppressed the epithelial morphological changes, leading to the failure of stem cell formation. Our findings strongly suggest that the adult stem cells originate from the larval absorptive cells expressing Ror2, which require Wnt5a/Ror2 signaling for their dedifferentiation accompanied by changes in cell morphology.

MATERIALS
Product Number
Brand
Product Description

Sigma-Aldrich
Magnesium chloride, anhydrous, ≥98%
Sigma-Aldrich
Magnesium chloride solution, PCR Reagent, 25 mM MgCI2 solution for PCR
Sigma-Aldrich
Magnesium chloride solution, for molecular biology, 1.00 M±0.01 M
Sigma-Aldrich
HEPES, ≥99.5% (titration)
Sigma-Aldrich
Hydrocortisone, meets USP testing specifications
Sigma-Aldrich
Hydrocortisone, BioReagent, suitable for cell culture
Sigma-Aldrich
HEPES, BioPerformance Certified, ≥99.5% (titration), suitable for cell culture
Supelco
Hydrocortisone, Pharmaceutical Secondary Standard; Certified Reference Material
Sigma-Aldrich
Hydrocortisone, ≥98% (HPLC)
USP
Hydrocortisone, United States Pharmacopeia (USP) Reference Standard
Sigma-Aldrich
HEPES buffer solution, 1 M in H2O