Establishment of Intestinal Stem Cell Niche During Amphibian Metamorphosis - Current Topics in Developmental Biology - page 299

CHAPTER ELEVEN

Establishment of Intestinal Stem
Cell Niche During Amphibian
Metamorphosis

Atsuko Ishizuya-Oka 1 , Takashi Hasebe
Department of Biology, Nippon Medical School, Kawasaki, Kanagawa, Japan
1

Corresponding author: e-mail address: [e-mail]

Contents
1. Introduction 306

2. Adult Epithelial Development During Intestinal Remodeling 307

3. Origin of Adult Stem Cells 309

4. Niche Essential for Adult Stem Cell Development 311

5. Signaling Pathways Involved in Establishment of Stem Cell Niche 313

5.1 MMPs and juxtacrine signaling 314

5.2 Shh/BMP4 signaling pathway 315

5.3 Other signaling pathways 317

6. Evolutionary Consideration and Prospect 319

Acknowledgments 321

References 321

Abstract
In the amphibian intestine during metamorphosis, most of the larval epithelial cells un-
dergo apoptosis, whereas a small number of them survive. These cells dedifferentiate
into stem cells through interactions with the microenvironment referred to as “ stem cell
niche ” and generate the adult epithelium analogous to the mammalian counterpart.
Since all processes of the larval-to-adult intestinal remodeling can be experimentally
induced by thyroid hormone (TH) both in vivo and in vitro, the amphibian intestine pro-
vides us a valuable opportunity to study how adult stem cells and their niche are formed
during postembryonic development. To address this issue, a number of expression and
functional analyses of TH response genes have been intensely performed in the Xenopus
laevis over the past two decades, by using organ culture and transgenic techniques. We

here review recent progress in this field, focusing on key signaling pathways involved in
establishment of the stem cell niche and discuss their evolutionarily conserved roles in
the vertebrate intestine.