CELL SORTING-OUT IS MODULATED BY BOTH THE SPECIFICITY AND AMOUNT OF DIFFERENT CELL-ADHESION MOLECULES (CAMS) EXPRESSED ON CELL-SURFACES
CELL SORTING-OUT IS MODULATED BY BOTH THE SPECIFICITY AND AMOUNT OF DIFFERENT CELL-ADHESION MOLECULES (CAMS) EXPRESSED ON CELL-SURFACES
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DOI：
10.1073/pnas.86.18.7043
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发表时间：
1989-09-01
影响因子：
11.1
通讯作者：
EDELMAN, GM
中科院分区：
文献类型：
--
作者：
FRIEDLANDER, DR;MEGE, RM;EDELMAN, GM
细胞粘附分子（CAMs）是细胞表面的糖蛋白，可能在形态发生和组织发生中发挥多种作用，特别是在确定离散细胞群体的边界方面。为了研究CAM表达对体外细胞分离事件的影响，我们转染了编码两种不同特异性钙依赖性CAM的cdna，肝脏CAM （L-CAM）和结构相关分子n -钙粘蛋白。将这些cdna分别或一起导入通常不表达这些分子的小鼠肉瘤S180细胞中，产生分别为S180L、S180cadN和S180L/cadN的细胞系。产生了不同类型的细胞系，它们的CAM表达水平不同。在粘附实验中，S180L和S180cadN细胞通过各自的cam特异性聚集，S180L细胞不粘附在S180cadN细胞上。表达高水平CAM的细胞比表达低水平CAM的细胞聚集得更快。当两种细胞表达不同特异性的CAM或不同水平的相同CAM时，就会发生分离。S180L和S180cadN细胞均从未转染的细胞中分离出来，高表达L-CAM或高表达N-cadherin的细胞从低表达相同CAM的细胞中分离出来；在所有情况下，分离都被转染的CAM特异性抗体抑制。S180L细胞从S180cadN细胞中分离出来，但只有当两种CAMs的抗体一起应用时，这种分离才会被抑制。双转染的S180L/cadN细胞也从S180L细胞和S180cadN细胞中分选出来，该过程被非共享CAM抗体（分别为N-cadherin或L-CAM）抑制。细胞松弛素D和诺可唑抑制分选，这与微丝和微管在细胞运动中的可能作用一致，也与这些cam的作用依赖于与皮质细胞质组分的相互作用的证据一致。在这些研究中，仅使用两种cam的cdna，我们可以通过它们在分选试验中的行为区分出至少8种细胞系。这表明，在组织形成过程中，相对少量的cam在体内表达的定性和定量差异可能导致细胞群及其边界之间的多种模式。
Cell adhesion molecules (CAMs) are cell surface glycoproteins that may play a variety of roles in morphogenesis and histogenesis, particularly in defining borders of discrete cell populations. To examine the influence of CAM expression on such cell segregation events in vitro, we have transfected cells with cDNAs coding for two calcium-dependent CAMs of different specificity, the liver CAM (L-CAM) and the structurally related molecule N-cadherin. The cDNAs were introduced separately or together into murine sarcoma S180 cells, which normally do not express these molecules, to produce cell lines denoted S180L, S180cadN, and S180L/cadN, respectively. A number of cell lines of each type were produced that differed in their levels of CAM expression. In adhesion assays, S180L and S180cadN cells aggregated specifically via their respective CAMs, and S180L cells did not appear to adhere to S180cadN cells. Cells expressing high levels of each CAM aggregated more rapidly than cells expressing low levels. Segregation between two cell types occurred when they expressed CAMs of different specificity or different levels of the same CAM. S180L and S180cadN cells both sorted out from untransfected cells, and cells expressing high levels of either L-CAM or N-cadherin segregated from cells expressing low levels of the same CAM; in all cases segregation was inhibited by antibodies specific for the transfected CAM. S180L cells sorted out from S180cadN cells, but this segretation was inhibited only when antibodies to both CAMs were applied together. Doubly transfected S180L/cadN cells also sorted out from S180L cells and from S180cadN cells, and the process was inhibited by antibodies to the unshared CAM (N-cadherin or L-CAM, respectively). Cytochalasin D and nocodazole inhibited sorting-out, consistent with the probable role of microfilaments and microtubules in cell movement and in accord with evidence that the action of these CAMs depends on interactions with cortical cytoplasmic components. Using cDNAs for only two CAMs in these studies, we could distinguish at least eight cell lines by their behavior in sorting-out assays. This suggests that qualitative and quantitative differences in the expression in vivo of relatively small number of CAMs can lead to a large variety of patterns among cell collectives and their borders during tissue formation.