1. Coordinated expression of 3' Hox genes during murine embryonal gut development: An enteric Hox code 
Jolanta E. Pitera, Virpi V. Smith, Peter Thorogood, Peter J. Milla 
Gastroenterology 
Volume 117, Issue 6, Pages (December 1999)
DOI: /S (99)
Copyright © 1999 American Gastroenterological Association Terms and Conditions

2. Fig. 1
Graphic representation of the expression of Hox genes from paralogous groups 4 and 5 and expression of markers for neural crest cells, c-ret, and Hoxb5 protein and α–smooth muscle actin in gut primordia at embryonal days E8.5–E16.5. AIP, anterior intestinal portal; PIP, posterior intestinal portal; OE, esophagus; S, stomach; PCG, prececal gut; PG, postcecal gut; C, cecum; SI, small intestine; LI, large intestine; NA, data unavailable; n, total number of pregnant CD1 mice used for in situ experiments and immunohistochemistry with an average of 8 embryos per mouse.
Gastroenterology  , DOI: ( /S (99) )
Copyright © 1999 American Gastroenterological Association Terms and Conditions

3. Fig. 2
(A–O) In situ hybridization of genes from Hox paralogous group 4 in whole mounts of gut primordia at E10.5–E17.5. In this and all subsequent figures, the rostral part of the gut is at the top of the figure. L, lung buds; S, stomach; PCG, prececal gut; PG, postcecal gut; OE, esophagus; SI, small intestine; LI, large intestine; C, cecum; K, kidney. (A) Rostral expression of Hoxa4 in the stomach and rostral prececal gut at E10.5. Strong expression of Hoxa4 in (B) E11.5 and (C) E12.5 gut. Note the gap (arrowhead) marking the rostral expression boundary in the prececal gut. No expression can be seen in the postcecal gut (*). (D) Hoxa4 expression expands into the large intestine at E16.5. Hoxb4 expression at (E) E10.5 and (F) E11.5 in the stomach and prececal gut with a sharp distal boundary near the prospective cecum (C). No expression can be seen in the postcecal gut (*, F). (G) Hoxb4 expression at E12.5 with a caudal expression boundary still present near the cecum (arrow). Strong color in the stomach is caused by partial probe trapping. (H) At E15.5, there is an expansion of Hoxb4 expression into the large intestine. (I) Hoxc4 expression in the stomach and postcecal gut at E11.5. (J) At E12.5, Hoxc4 expression appears in the esophagus and prececal and postcecal gut. (K) Hoxc4 expression in the second half of gestation in rostral small and large intestine at E16.5. (L) Hoxd4 expression starts at E9.75 in the caudal gut (arrowhead). (M) At E11.5, Hoxd4 expression expands toward the prospective cecum (arrowhead). There is no expression in prececal gut (*). (N) At E12.5, Hoxd4 expression is still present in the postcecal gut (arrowhead). (O) At E16.5, Hoxd4 expression remains confined to the developing cecum (C). Original magnifications: A, 12.5×; B, 10×; C, 8×; D, 5×; E, 12.5×; F, 10×; G, 8×; H, 5×; I, 10×; J, 8×; K, 14×; L, 14×; M, 10×; N, 8×; O, 6×.
Gastroenterology  , DOI: ( /S (99) )
Copyright © 1999 American Gastroenterological Association Terms and Conditions

4. Fig. 3
(A–H) Cellular localization of genes from Hox paralogous group 4 in vibratome sections through the gut primordium at E11.5–E16.5. E, endoderm; M, mesoderm; OE, esophagus; S, stomach. (A) A transverse section of E12.5 gut showing Hoxa4 expression in the developing circular muscle layer within the peripheral mesoderm (M) and in the gut mucosa (E). (B) A transverse section through the postcecal gut (E12.5) showing Hoxd4 expression in the outer layer of the gut mesoderm (M). (C) A sagittal section of E12.5 esophagus and stomach showing Hoxc4 expression in the esophageal endoderm and underlying mesoderm (arrowhead). (D) A transverse section through the rostral prececal gut at E12.5. Expression of Hoxc4 is present in the mesoderm (M) and gut mucosa. (E) A sagittal section through the prececal and postcecal gut of E12.5 embryo showing expression of Hoxc4 in the endoderm and underlying mesoderm (arrowhead) of the prececal gut and in the mesoderm (arrows) and endoderm of the postcecal gut region. Hoxa4 expression in the prospective (F) muscularis mucosae (arrowhead) and (E) epithelium in E16.5 small intestine. (G) Hoxb4 expression (E16.5) in the developing muscularis propria (arrowhead). (H) Hoxc4 expression at E16.5 in the gut mucosa (arrow). Original magnifications: A, 200×; B, 100×; C, 50×; D, 100×; E, 50×; F, 100×; G, 100×; H, 50×.
Gastroenterology  , DOI: ( /S (99) )
Copyright © 1999 American Gastroenterological Association Terms and Conditions

5. Fig. 4
(A–N) In situ hybridization and immunohistochemistry of genes from Hox paralogous group 5 in whole mounts of gut primordia at E10.5–E17.5. Rostral gut is on top. S, stomach; PG, postcecal gut; PCG, prececal gut; L, lung buds; C, cecum; OE, esophagus; SI, small intestine; LI, large intestine. (A) E10.5 and (B) E11.5 gut with nested expression domains of Hoxa5 confined to the dorsolateral edge of the stomach (*). Expression starting at E11.5 in the growing cecum (C). (C) At E12.5, Hoxa5 expression starts in the prececal gut and continues to be expressed in the stomach (arrowheads) and in the cecum (*). (D) At E16.5, Hoxa5 expression expands into the large intestine (arrow). (E) Hoxb5 expression in the stomach at E10.5. (F) Expression of Hoxb5 in the developing enteric neurons of the prececal gut at E11.5. (G) Hoxb5 expression. Note the caudal boundary at the level of the cecum (arrow) at E12.5. (H) Hoxb5 expression at E17.5 in the enteric neurons of small and large intestine. (I) Hoxc5 strong expression in the rostral stomach (arrowhead) and prececal and postcecal gut (*) at E10.5. (J) Hoxc5 expression in the stomach (*) and prececal gut (arrowhead) at E11.5. (K) Expression in the postcecal gut is switched off at E11.5 and shows a rostral boundary in the cecum (arrowhead). (L) At E13.5, Hoxc5 expression is shifted rostrally into the ventral part of the cecum (*) and small intestine (arrow). (M) Higher magnification of the cecum shown in L. (N) At E16.5, Hoxc5 is still expressed in the small intestine. Original magnifications: A, 12.5×; B, 10×; C, 8×; D, 5×; E, 12.5×; F, 10×; G, 10×; H, 25×; I, 15×; J, 14×; K, 14×; L, 7×; M, 20×; N, 5×.
Gastroenterology  , DOI: ( /S (99) )
Copyright © 1999 American Gastroenterological Association Terms and Conditions

6. Fig. 5
(A–G) Cellular localization of the expression of Hox genes from paralogous group 5 in vibratome sections through the whole mounts of E10.5–E17.5. E, endoderm; M, mesoderm; S, stomach; PCG, prececal gut; PG, postcecal gut; C, cecum; OE, esophagus; LI, large intestine; SI, small intestine. (A) A transverse section showing nested expression of Hoxa5 in the mesoderm of dorsal stomach (*) at E10.5. (B) A sagittal section through the stomach of E10.5 gut showing Hoxb5 expression in the mesoderm (M). (C) A sagittal section through the stomach and prececal gut at E10.5 with expression of Hoxc5 in the rostral stomach and the mesoderm of prececal gut (*). (D) A sagittal section through the prececal gut at E11.5 showing expression of Hoxb5 in the enteric neuroblasts localized in peripheral mesoderm. (E) A sagittal section through the esophagus (E11.5) showing expression of Hoxc5 in the endoderm (arrow). (F) Hoxc5 expression in the intestinal epithelium (E) and the prospective muscularis propria (arrowhead) at E16.5. (G) Hoxa5 expression in the prospective muscularis mucosae (arrowhead) at E16.5. (H–L) Whole-mount in situ hybridization for c-ret in the developing gut. (H and I) At E10.5 and E11.5, expression of c-ret is visible in the neuroblasts of the stomach and prececal gut. (J) c-ret expression in the developing enteric neurons of the whole gut at E13.5. c-ret rostrocaudal wave of a decrease in expression at (K) E15.5 and (L) a subsequent restoration of the expression at E17.5. K, kidney. Original magnifications: A, 200×; B, 200×; C, 50×; D, 50×; E, 200×; F, 100×; G, 100×; H, 20×; I, 10×; J, 7×; K, 5×; L, 4×.
Gastroenterology  , DOI: ( /S (99) )
Copyright © 1999 American Gastroenterological Association Terms and Conditions

7. Fig. 6
(A–D) Combined in situ hybridization for c-ret (purple) and hoxb-5 immunostaining (red, or reddish brown) in sagittal sections of embryonal gut (A–C) and in the gut of 2-week-old pups (D). SI, small intestine; LI, large intestine; M, mesoderm; E, endoderm. (A) A section through the whole mount at E14.5 showing decreased c-ret expression in the small intestine with Hoxb5 expression unchanged. In the large intestine, c-ret and Hoxb5 are still coexpressed in the enteric neurons. (B) A transverse section through the large intestine at E13.5 showing both expression and coexpression of Hoxb5 and c-ret. (C) A sagittal section through E14.5 whole mounts showing c-ret and Hoxb5 coexpression in the developing enteric neurons. (D) A sagittal section through the large intestine in 2-week-old pup gut showing coexpression of Hoxb5 and c-ret in the same enteric nerves. Note the presence of c-ret transcripts (purple) in the cytoplasm surrounding the Hoxb5 (red) protein located in the cell nuclei. (E and F) Vibrotome sections of a whole mount after dual immunostaining for Hoxb5 and α–smooth muscle actin show a close association of enteric neuroblasts (brown) and the developing muscle layer (red) in the outer gut mesoderm at E11.5 in the stomach and at E12.5 in the developing gut. (E) A transverse section through the stomach at E11.5 showing a close association of Hoxb5-expressing neuroblasts (brown) and the muscle layer (red). (F) A sagittal section through the gut at E12.5 showing well-developed layers of enteric neurons expressing Hoxb5 (brown) and muscles, expressing α–smooth muscle actin (red). Original magnifications: A, 100×; B, 200×; C–F, 400×.
Gastroenterology  , DOI: ( /S (99) )
Copyright © 1999 American Gastroenterological Association Terms and Conditions