Establishment of the Visceral Embryonic Midline Is a Dynamic Process that Requires Bilaterally Symmetric BMP Signaling.
The vertebrate body plan contains both dorsal and ventral midline structures. While dorsal midline structures have been extensively studied, formation of ventral midline structures, and how they become aligned with the dorsal midline, is a fundamental aspect of vertebrate development that is poorly understood. This study uses the chick dorsal mesentery (DM) as a model for investigating the formation of ventral midline structures. We document formation of the DM by epithelial-to-mesenchymal transition (EMT) and medial ingression of the lateral plate coelomic lining and show that DM positioning is a fundamentally dynamic process regulated by relative levels of bone morphogenetic protein (BMP) signaling in the two sides of the ingressing lateral plate. Disruption of this process causes misalignment of the DM and disturbances during initial stages of lung morphogenesis. Since the dorsal midline is a source of BMP antagonists, these results suggest a mechanism for aligning the dorsal and ventral embryonic midlines.
Department of Genetics and Developmental Biology, Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa 31096, Israel.
Alaa A
AA
Arraf
Department of Genetics and Developmental Biology, Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa 31096, Israel.
Ronit
R
Yelin
Department of Genetics and Developmental Biology, Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa 31096, Israel.
Inbar
I
Reshef
Institut für Molekularbiologie, Medizinische Hochschule Hannover, 30625 Hannover, Germany.
Andreas
A
Kispert
Department of Genetics and Developmental Biology, Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa 31096, Israel. Electronic address: tschulth@tx.technion.ac.il.
Thomas M
TM
Schultheiss
D000818:Animals; D001011:Aorta / Q000196:embryology; D019521:Body Patterning; D019485:Bone Morphogenetic Proteins / Q000378:metabolism*; D002642:Chick Embryo; D058750:Epithelial-Mesenchymal Transition; D008648:Mesoderm / Q000196:embryology / Q000378:metabolism; D010641:Phenotype; D015398:Signal Transduction; D014781:Viscera / Q000196:embryology* / Q000378:metabolism*
D019485:Bone Morphogenetic Proteins