The role of E-cadherin and integrins in mesoderm differentiation and migration at the mammalian primitive streak

作者：Carol A. Burdsal, Caroline H. Damsky, Roger A. Pedersen · 发表于：Development · 年份：1993 · DOI：10.1242/dev.118.3.829 · 被引用次数：206 · 研究领域：Wnt/β-catenin signaling in development and cancer、Developmental Biology and Gene Regulation、Skin and Cellular Biology Research

ABSTRACT We have examined the role of cell-cell and cell-extracellular matrix (ECM) interactions during mesoderm differentiation and migration at the primitive streak of the mouse embryo with the use of function-perturbing antibodies. Explants of epiblast or mesoderm tissue dissected from the primitive streak of 7.5- to 7.8-day mouse embryos were cultured on a fibronectin substratum in serum-free, chemically defined medium. After 16-24 hours in culture, cells in explants of epiblast exhibited the typical close-packed morphology of epithelia, and the tissue remained as a coherent patch of cells that were shown to express transcripts of the cytokeratin Endo B by in situ analysis. In contrast, cells in explants of primitive streak mesoderm exhibited a greatly flattened, fibroblastic morphology, did not express Endo B transcripts, and migrated away from the center of the explant. As epiblast cells in vivo undergo the epithelial-mes-enchymal transition at the primitive streak, they cease expressing the prominent calcium-sensitive cell adhesion molecule E-cadherin (uvomorulin, Cell-CAM 120/80). We asked whether the loss of E-cadherin expression was a passive result of differentiation or if it might play a more causative role in mesoderm differentiation and migration. Culture with function-perturbing antibodies against E-cadherin caused cells within epiblast explants to lose cell-cell contacts, to flatten, and to assume a mes-enchymal morphology; they were also induced to migrate. A...