Dynamic patterning at the pylorus: Formation of an epithelial intestine–stomach boundary in late fetal life

• Published in: Developmental dynamics Vol. 238; no. 12; pp. 3205 - 3217
• Main Authors: Li, Xing, Udager, Aaron M., Hu, Chunbo, Qiao, Xiaotan T., Richards, Neil, Gumucio, Deborah L.
• Format: Journal Article
• Language: English
• Published: New York Wiley‐Liss, Inc 01.12.2009
• Subjects: Animals; Embryo, Mammalian; Female; Fetal Development - genetics; Fetal Development - physiology; Gata3; Gene Expression Profiling; Gestational Age; Hedgehog signaling; intestinal identity; Intestinal Mucosa - embryology; Intestinal Mucosa - metabolism; Intestines - embryology; Intestines - metabolism; Kruppel-Like Transcription Factors - genetics; Lac Operon - genetics; Mice; Mice, Inbred C57BL; Mice, Transgenic; microarray analysis; Oligonucleotide Array Sequence Analysis; Pregnancy; Pylorus - embryology; Pylorus - metabolism; Stomach - embryology; Stomach - metabolism; Wnt signaling; Zinc Finger Protein GLI1
• ISSN: 1058-8388; 1097-0177
• DOI: 10.1002/dvdy.22134

In the adult mouse, distinct morphological and transcriptional differences separate stomach from intestinal epithelium. Remarkably, the epithelial boundary between these two organs is literally one cell thick. This discrete junction is established suddenly and precisely at embryonic day (E) 16.5, by sharpening a previously diffuse intermediate zone. In the present study, we define the dynamic transcriptome of stomach, pylorus, and intestinal tissues between E14.5 and E16.5. We show that establishment of this boundary is concomitant with the induction of over a thousand genes in intestinal epithelium, and these gene products provide intestinal character. Hence, we call this process intestinalization. We identify specific transcription factors (Hnf4γ, Creb3l3, and Tcfec) and examine signaling pathways (Hedgehog and Wnt) that may play a role in this process. Finally, we define a unique expression domain at the pylorus itself and detect novel pylorus‐specific patterns for the transcription factor Gata3 and the secreted protein nephrocan. Developmental Dynamics 238:3205–3217, 2009. © 2009 Wiley‐Liss, Inc.