The terminology of “endoderm” is confusing for the mouse, where first, the layer of extraembryonic tissues covering the epiblast is also termed endoderm, and second, the endoderm is initially the outermost germ layer of the embryo due to an “inside-out” arrangement of germ layers. 内胚葉という呼称が混乱を招きやすい理由2つ
The extraembryonic “endoderm” surrounding the early epiblast is the visceral endoderm and it is derived from the inner cell mass of the blastocyst
The epiblast of the mouse embryo contains the precursors of the definitive endoderm 内胚葉の細胞の起源は、エピブラスト細胞
The epiblast of the mouse embryo is a cup-shaped epithelial layer covered on its basal surface by the visceral endoderm. カップ状の形状
After egression from the primitive streak, definitive endoderm cells are incorporated into the pre-existing epithelium, the visceral endoderm. 内胚葉細胞は置き換えが起きる
マウス初期胞胚がエッグシリンダーの形状をとることについて:人間との違い
Mice go through egg cylinder stages of development, whereas primates form a bi-laminar disc.
New paper by the Zernicka-Goetz group shows that cross-talk between the embryonic epiblast and the extraembryonic trophectoderm orchestrates the transformation of the blastocyst to the egg cylinder
Modeling Mammalian Commitment to the Neural Lineage Using Embryos and Embryonic Stem Cells REVIEW article Front. Physiol., 11 July 2019 Sec. Developmental Physiology Volume 10 – 2019 | Each blastomere is totipotent and expresses genetic markers of the future pluripotent inner cell mass (ICM) (e.g., Oct4, Nanog and Rex1) as well as extraembryonic lineages (e.g., Gata6 and Sox17) (Figure 1; Medvedev et al., 2008; Toyooka et al., 2008; Kellner and Kikyo, 2010; Niakan et al., 2010; Wamaitha et al., 2015). At 5.5 dpc the embryo is known as the egg cylinder.
前方臓側内胚葉 anterior visceral endoderm (AVE)とは
A–P polarity is established in the mouse embryo when the distal visceral endoderm (DVE) migrates toward the future anterior side at embryonic day (E) 5.5 (refs. 2,3,4,5,6,7). Concomitant with DVE migration, all visceral endoderm (VE) cells in the embryonic region undergo global movement, resulting in the localization of some VE cells at the distal tip of the embryo. These VE cells at the distal tip will become the anterior visceral endoderm (AVE) and migrate toward the future anterior side of the embryo by following the migration of DVE8.
Both Nodal signalling and stochasticity select for prospective distal visceral endoderm in mouse embryos Nature Communications Published: 14 November 2017 https://www.nature.com/articles/s41467-017-01625-x
Nodal signaling from the visceral endoderm is required to maintain Nodal gene expression in the epiblast and drive AVE migration Dev Biol. 2015 Apr 1; 400(1): 1–9. doi: 10.1016/j.ydbio.2014.12.016 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4806383/
Role of the anterior visceral endoderm in restricting posterior signals in t he mouse embryo February 2001The International Journal of Developmental Biology 45(1):311-20 February 200145(1):311-20 https://www.researchgate.net/publication/12041905_Role_of_the_anterior_visceral_endoderm_in_restricting_posterior_signals_in_the_mouse_embryo