Duband J L
ENS, laboratoire de physiopathologie du développement du CNRS, Paris, France.
Reprod Nutr Dev. 1990;30(3):379-95.
The neural crest provides a useful paradigm for cell migration and modulations in cell adhesion during morphogenesis. In the present review, we describe the major findings on the role of the extracellular matrix glycoprotein fibronectin and its corresponding integrin receptor in the locomotory behavior of neural crest cells. In vivo, fibronectin is associated with the migratory routes of neural crest cells and, in some cases, it disappears from the environment of the cells as they stop migrating. In vitro, neural crest cells show a great preference for fibronectin substrates as compared to other matrix molecules. Both in vivo and in vitro, neural crest cell migration can be specifically inhibited by antibodies or peptides that interfere with the binding of fibronectin to its integrin receptor. However, the migratory behavior of neural crest cells cannot result solely from the interaction with fibronectin. Thus, neural crest cells exhibit a particular organization of integrin receptors on their surface and develop a cytoskeletal network which differs from that of non-motile cells. These properties are supposed to permit rapid changes in the shape of cells and to favor a transient adhesion to the substratum. Recent findings have established that different forms of fibronectin may occur, which differ by short sequences along the molecule. The functions of most of these sequences are not known, except for 1 of them which carries a binding site for integrin receptors. We have demonstrated that this site is recognized by neural crest cells and plays a crucial role in their displacement. It is therefore possible that the forms of fibronectin carrying this sequence are not evenly distributed in the embryo, thus allowing migrating neural crest cells to orientate in the embryo. Fibronectin would then not only play a permissive role in embryonic cell motility, but have an instructive function in cell behavior.
神经嵴为形态发生过程中的细胞迁移及细胞黏附调节提供了一个有用的范例。在本综述中，我们描述了关于细胞外基质糖蛋白纤连蛋白及其相应整合素受体在神经嵴细胞运动行为中作用的主要研究结果。在体内，纤连蛋白与神经嵴细胞的迁移路径相关，并且在某些情况下，当细胞停止迁移时，它会从细胞环境中消失。在体外，与其他基质分子相比，神经嵴细胞对纤连蛋白底物表现出极大的偏好。在体内和体外，神经嵴细胞的迁移都可被干扰纤连蛋白与其整合素受体结合的抗体或肽特异性抑制。然而，神经嵴细胞的迁移行为不能仅由与纤连蛋白的相互作用导致。因此，神经嵴细胞在其表面呈现出整合素受体的特定组织形式，并形成一个与非运动细胞不同的细胞骨架网络。这些特性被认为可以使细胞形状快速改变，并有利于与底物的短暂黏附。最近的研究结果表明，可能存在不同形式的纤连蛋白，它们在分子上的短序列有所不同。除了其中一个带有整合素受体结合位点的序列外，这些序列中的大多数功能尚不清楚。我们已经证明这个位点能被神经嵴细胞识别，并在它们的迁移中起关键作用。因此，携带该序列的纤连蛋白形式可能在胚胎中分布不均，从而使迁移的神经嵴细胞能够在胚胎中定向。这样看来，纤连蛋白不仅在胚胎细胞运动中起允许作用，而且在细胞行为中具有指导功能。
