Miller S A, Bresee K L, Michaelson C L, Tyrell D A
Department of Biology, Hamilton College, Clinton, New York 13323.
Anat Rec. 1994 Feb;238(2):225-36. doi: 10.1002/ar.1092380209.
Patterns of cell proliferation in ectoderm epithelium that will form avian amnion correlate with morphogenesis, but not in an obvious pattern with respect to large-scale folding. At sites where the pre-axial amnion folds will first appear in 4- to 8-somite embryos, patterns of proliferation do not separate into domains that presage location of the single pre-axial fold that is commonly described in embryology texts. Instead, increased cell proliferation occurs in a significant, bilateral pattern. In stages with 13 to 27 somites, when lateral amnionic folds are prominent, five paraxial domains of cell proliferation correlate with morphology and show decreasing levels of cell proliferation with distance from the neural axis. Slowly growing areas surround rapidly growing areas and could assist buckling of epithelium by providing constraints on expansion of faster growing areas. Proliferation domains in ectoderm correlate with morphology and morphological events when localized changes in cell shape are lacking and suggest a role for differential cell proliferation in formation of large-scale epithelial folds in early chick embryos.
将形成鸟类羊膜的外胚层上皮中的细胞增殖模式与形态发生相关，但在大规模折叠方面没有明显的模式。在4至8体节胚胎中首先出现轴前羊膜褶皱的部位，增殖模式并未分离成预示胚胎学教科书中通常描述的单个轴前褶皱位置的区域。相反，细胞增殖以显著的双侧模式增加。在13至27体节的阶段，当外侧羊膜褶皱突出时，五个近轴细胞增殖区域与形态相关，并显示出细胞增殖水平随距神经轴距离的增加而降低。缓慢生长的区域围绕着快速生长的区域，并可能通过对快速生长区域的扩张提供限制来协助上皮的屈曲。当缺乏细胞形状的局部变化时，外胚层中的增殖区域与形态和形态学事件相关，并表明差异细胞增殖在早期鸡胚大规模上皮褶皱形成中起作用。
