title: Mechanical control of notochord morphogenesis by extra-embryonic tissues in mouse embryos.
abstract: Mammalian embryos develop in coordination with extraembryonic tissues, which support embryonic development by implanting embryos into the uterus, supplying nutrition, providing a confined niche, and also providing patterning signals to embryos. Here, we show that in mouse embryos, the expansion of the amniotic cavity (AC), which is formed between embryonic and extraembryonic tissues, provides the mechanical forces required for a type of morphogenetic movement of the notochord known as convergent extension (CE) in which the cells converge to the midline and the tissue elongates along the antero-posterior (AP) axis. The notochord is stretched along the AP axis, and the expansion of the AC is required for CE. Both mathematical modeling and physical simulation showed that a rectangular morphology of the early notochord caused the application of anisotropic force along the AP axis to the notochord through the isotropic expansion of the AC. AC expansion acts upstream of planar cell polarity (PCP) signaling, which regulates CE movement. Our results highlight the importance of extraembryonic tissues as a source of the forces that control the morphogenesis of embryos.
authors: Department of Cell Fate Control, Institute for Molecular Embryology and Genetics, Kumamoto University, 2-2-1 Honjo, Chuo-ku, Kumamoto 860-0811, Japan; Laboratory for Cell Asymmetry, RIKEN Center for Developmental Biology, 2-2-3 Minatojima-minamimachi, Chuo-ku, Kobe 650-0047, Japan; Graduate School of Medicine, Osaka University, 2-2 Suita, Osaka 565-0871, Japan.
authors: Yu
authors: Y
authors: Imuta
authors: Division of Embryology, National Institute for Basic Biology, 5-1 Higashiyama, Myodaiji, Okazaki 444-8787, Japan; Graduate University of Advanced Studies (Sokendai), 5-1 Higashiyama, Myodaiji, Okazaki 444-8787, Japan.
authors: Hiroshi
authors: H
authors: Koyama
authors: Division of Embryology, National Institute for Basic Biology, 5-1 Higashiyama, Myodaiji, Okazaki 444-8787, Japan; Graduate School of Biostudies, Kyoto University, Yoshidakonoecho, Sakyo-ku, Kyoto 606-8501, Japan.
authors: Dongbo
authors: D
authors: Shi
authors: 4-Dimensional Tissue Analysis Unit, RIKEN Center for Developmental Biology, 2-2-3 Minatojima-minamimachi, Chuo-ku, Kobe 650-0047, Japan.
authors: Mototsugu
authors: M
authors: Eiraku
authors: Division of Embryology, National Institute for Basic Biology, 5-1 Higashiyama, Myodaiji, Okazaki 444-8787, Japan; Graduate University of Advanced Studies (Sokendai), 5-1 Higashiyama, Myodaiji, Okazaki 444-8787, Japan.
authors: Toshihiko
authors: T
authors: Fujimori
authors: Department of Cell Fate Control, Institute for Molecular Embryology and Genetics, Kumamoto University, 2-2-1 Honjo, Chuo-ku, Kumamoto 860-0811, Japan; Program for Leading Graduate Schools "HIGO (Health life science: Interdisciplinary and Glocal Oriented) Program", Kumamoto University, 2-2-1 Honjo, Chuo-ku, Kumamoto 860-0811, Japan. Electronic address: sasaki@kumamoto-u.ac.jp.
authors: Hiroshi
authors: H
authors: Sasaki
mesh_terms: D000818:Animals; D019521:Body Patterning / Q000502:physiology; D002465:Cell Movement / Q000502:physiology; D016764:Cell Polarity / Q000502:physiology; D004622:Embryo, Mammalian / Q000502:physiology*; D047108:Embryonic Development / Q000502:physiology*; D051379:Mice; D009024:Morphogenesis / Q000502:physiology*; D009672:Notochord / Q000196:embryology*
keywords: Amniotic cavity; Convergent extension; Live imaging; Mechanical forces; Mouse embryogenesis; Notochord