title: Analysis of duodenojejunal flexure formation in mice: implications for understanding the genetic basis for gastrointestinal morphology in mammals.
abstract: The mammalian gut undergoes morphological changes during development. We studied the developing mouse duodenojejunal flexure (DJF) to elucidate the mechanism of formation. During embryonic days 10.75-13.75, DJF formation was morphologically classified into three stages: the expansion stage, flexure formation stage, and flexure elongation stage. From the expansion to the flexure formation stages, the DJF wall showed asymmetric morphology and proliferation along the left-right intestinal axis. From the flexure formation to the flexure elongation stage, the DJF started to bend dorsally with counterclockwise rotation along the antero-caudal intestinal axis, indicating that the original right side of the duodenum was rotated towards the dorsal body wall during development of the DJF. The direction of attachment of the dorsal mesentery to the DJF did not correspond to the bending direction of the DJF during flexure formation, and this finding indicated that the dorsal mesentery contributed very little to DJF formation. During DJF formation, Aldh1a2 and hedgehog mRNAs were detected at the DJF, and their expression levels differed along the bending axis. In conclusion, DJF formation might be triggered by asymmetric morphology and proliferation along the left-right intestinal axis under the control of retinoic acid and hedgehog signaling.
authors: Laboratory of Anatomy, Department of Biomedical Sciences, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo, Japan.
authors: Sawa
authors: S
authors: Onouchi
authors: Osamu
authors: O
authors: Ichii
authors: Saori
authors: S
authors: Otsuka
authors: Yoshiharu
authors: Y
authors: Hashimoto
authors: Yasuhiro
authors: Y
authors: Kon
mesh_terms: D000818:Animals; D049109:Cell Proliferation; D004386:Duodenum / Q000166:cytology / Q000196:embryology* / Q000502:physiology; D020869:Gene Expression Profiling; D007583:Jejunum / Q000166:cytology / Q000196:embryology* / Q000502:physiology; D051379:Mice; D008810:Mice, Inbred C57BL; D008953:Models, Anatomic; D023421:Models, Animal; D012333:RNA, Messenger / Q000378:metabolism; D015398:Signal Transduction / Q000235:genetics
chemical_list: D012333:RNA, Messenger
keywords: development; duodenojejunal flexure; flexure formation; morphogenesis
references: Mech Dev. 2005 Jan;122(1):3-25
references: 15582774
references: Annu Rev Physiol. 2011;73:213-37
references: 21054163
references: Dev Biol. 2009 Feb 15;326(2):285-94
references: 19100728
references: Dev Dyn. 2009 Dec;238(12):3111-25
references: 19924810
references: Am J Pathol. 2001 Dec;159(6):2321-9
references: 11733381
references: Dev Biol. 2011 Sep 1;357(1):227-34
references: 21726547
references: Development. 2010 May;137(10):1721-9
references: 20430747
references: J Surg Res. 2012 Jun 1;175(1):82-7
references: 21492869
references: Physiol Rev. 2007 Oct;87(4):1343-75
references: 17928586
references: Nucl Recept Signal. 2009;7:e002
references: 19381305
references: Biol Open. 2013 Feb 15;2(2):144-55
references: 23429478
references: Cell Biosci. 2012 Mar 22;2(1):11
references: 22439772
references: Nat Rev Genet. 2008 Jul;9(7):541-53
references: 18542081
references: Proc Natl Acad Sci U S A. 2008 Jun 24;105(25):8499-506
references: 18574143
references: Int J Mol Med. 2006 Dec;18(6):1019-23
references: 17089004
references: Bioessays. 2007 Feb;29(2):120-32
references: 17226800
references: Nature. 2011 Aug 03;476(7358):57-62
references: 21814276
references: Dev Dyn. 2010 Mar;239(3):941-53
references: 20063415
references: Int J Biol Sci. 2006;2(2):38-47
references: 16733532
references: Dev Cell. 2008 Dec;15(6):801-12
references: 19081070
references: Dev Dyn. 2011 Mar;240(3):501-20
references: 21246663
references: Dev Cell. 2002 Jun;2(6):695-706
references: 12062082
references: Genes Dev. 2009 Feb 1;23(3):265-77
references: 19204114
references: Biochem Biophys Res Commun. 2007 Jul 13;358(4):968-75
references: 17521608
references: Exp Cell Res. 2011 Nov 15;317(19):2702-10
references: 21978911
references: Dev Cell. 2008 Jul;15(1):134-45
references: 18606147
references: Dev Dyn. 2006 Aug;235(8):2266-75
references: 16786581