哺乳類の初期胚で胚盤胞ができたときに、最初はNanogとGATA6の両方を発現した細胞集団が、やがてNanogを発現するものは上層、GATA6を発現するものは下層へと分離します。
https://www.sciencedirect.com/science/article/pii/S1534580714002317
ここで発生学として興味深い問題はまず、最初は一つの細胞の中でNanogとGATA6を発現していたのに、なぜやがて、どちらかしか発現しなくなるのか?という問題です。2番目の問題として、Nanog陽性細胞は上側に、GATA6陽性細胞は下側に(胚盤胞腔(胞胚腔)に面する側)に分かれるメカニズムは何かということです。
Nanog陽性細胞またはGATA6陽性細胞への分化のメカニズム
Nanog陽性細胞とGATA6陽性細胞が位置的に分離するメカニズム
Fig. 4. Two N-cad-transfected L cell clones (LN4 and LN2a), expressing N-cad at their surfaces in the ratio of 2.4:1, were stained with the fluorescent membrane intercalating dyes PKH2 and PKH26, (Sigma-Aldrich), mixed in equal proportions and cultured as hanging drops. (A) Confocal optical section through an aggregate after 4 h of incubation, showing initial cell mixture. (B) Confocal optical section through another aggregate after 24 h of incubation. As predicted by the DAH, the LN2a cell line, expressing the lower level of N-cad (σ = 2.4 erg/cm2), here labeled red, envelops the LN4 cell line expressing higher amounts of N-cad (σ = 5.6 erg/cm2), here labeled green.
関連文献
- https://en.wikipedia.org/wiki/Malcolm_Steinberg
- https://www.eoht.info/page/Malcolm%20Steinberg
- The differential adhesion hypothesis: a direct evaluation Ramsey A Foty 1, Malcolm S Steinberg Dev Biol . 2005 Feb 1;278(1):255-63. doi: 10.1016/j.ydbio.2004.11.012. https://www.sciencedirect.com/science/article/pii/S0012160604008048?via%3Dihub
- Cell sorting-out is modulated by both the specificity and amount of different cell adhesion molecules (CAMs) expressed on cell surfaces D R Friedlander 1, R M Mège, B A Cunningham, G M Edelman Proc Natl Acad Sci U S A . 1989 Sep;86(18):7043-7. doi: 10.1073/pnas.86.18.7043. PMID: 2780560 PMCID: PMC297989 DOI: 10.1073/pnas.86.18.7043 https://www.pnas.org/doi/epdf/10.1073/pnas.86.18.7043(PDF)