Dynamic behavior of the cadherin-based cell-cell adhesion system during Drosophila gastrulation
Dynamic behavior of the cadherin-based cell-cell adhesion system during Drosophila gastrulation
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DOI：
10.1006/dbio.1998.9047
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发表时间：
1998-11-15
影响因子：
2.7
通讯作者：
Takeichi, M
中科院分区：
文献类型：
--
作者：
Oda, H;Tsukita, S;Takeichi, M
在果蝇原肠发育过程中，形态发生是一系列细胞形态变化和细胞运动的过程，可能涉及细胞间的黏附作用。在目前的研究中，我们研究了形态发生事件中基于钙粘附素的细胞-细胞黏附的动态方面，以评估其对形态发生的贡献。De-钙粘附素和Dn-钙粘附素在推测的外胚层和中胚层中在mRNA水平上表现出互补的表达模式。我们发现，在中胚层胚芽层中，钙粘附素的表达从DE-型转换为DN型，发生在中胚层决定基因twist和蜗牛的下游。然而，对它们的蛋白质表达模式的研究表明，在内陷过程中，中胚层细胞表面仍有相当数量的DE-钙粘附素，而在这个阶段，细胞表面没有出现DN-钙粘附素。进一步对DE-钙粘蛋白及其相关蛋白Armadillo(β-catenin)和Dα-catenin的定位进行免疫细胞化学分析，发现其分布的动态变化，并伴随着神经外胚层和中胚层细胞形态的变化。同时，基于钙粘附素-连环蛋白系统的黏附连接(AJ)被证明改变了它们的位置、大小和形态。基于钙粘附素的细胞-细胞黏附的这些动态方面似乎与以下方面有关：(1)胚层上皮的初步建立，(2)神经外胚层中细胞运动的获得，(3)细胞膜的折叠，以及(4)中胚层上皮向间充质的转化。这些观察表明，DE-钙粘附素-连环素黏附系统的行为可能在原肠形成过程中以一种循序渐进的方式进行调节，以执行连续的细胞形态转换。此外，在早期中胚层形态发生过程中，负责失去上皮细胞极性和消除先前存在的基于DE-钙粘附素的上皮连接的过程也被讨论，(C)1998年学术出版社。
During Drosophila gastrulation, morphogenesis occurs as a series of cell shape changes and cell movements which probably involve adhesive interactions between cells. In the present study, we examined the dynamic aspects of cadherin-based cell-cell adhesion in the morphogenetic events to assess its contribution to morphogenesis. DE- and DN-cadherin show complementary expression patterns in the presumptive ectoderm and mesoderm at the mRNA level. We found that switching of cadherin expression from the DE- to the DN-type in the mesodermal germ layer occurred downstream of the mesoderm-determination genes twist and snail. However, examination of their protein expression patterns showed that considerable amounts of DE-cadherin remained on the surfaces of mesodermal cells during invagination, while DN-cadherin did not appear on the cell surfaces at this stage. Further immunocytochemical analysis of the localizations of DE-cadherin and its associated proteins Armadillo (beta-catenin) and D alpha-catenin revealed dynamic changes in their distributions which were accompanied by changes in cell morphology in the neuroectoderm and mesoderm. Simultaneously, adherens junctions (AJs), based on the cadherin-catenin system, were shown to change their location, size, and morphology. These dynamic aspects of cadherin-based cell-cell adhesion appeared to be associated with the following: (1) initial establishment of the blastoderm epithelium, (2) acquisition of cell motility in the neuroectoderm, (3) cell sheet folding, and (4) epithelial to mesenchymal conversion of the mesoderm. These observations suggest that the behavior of the DE-cadherin-catenin adhesion system may be regulated in a stepwise manner during gastrulation to perform successive cell-morphology conversions. Moreover, the processes responsible for loss of epithelial cell polarity and elimination of preexisting DE-cadherin-based epithelial junctions during early mesodermal morphogenesis are discussed, (C) 1998 Academic Press.