Differentiation of neuronal growth cones: specialization of filopodial tips for adhesive interactions.
Differentiation of neuronal growth cones: specialization of filopodial tips for adhesive interactions.
复制标题
神经元生长锥的分化：丝状伪足尖端用于粘附相互作用的专门化。
DOI：
10.1073/pnas.82.23.8256
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发表时间：
1985
影响因子：
11.1
通讯作者：
Klein,WL
中科院分区：
文献类型：
--
作者：
Tsui,HC;Lankford,KL;Klein,WL
发育中的神经元的丝状伪足所形成的粘附性接触在神经突生长和突触连接的形成中是重要的。本工作采用视频增强对比度、微分干涉对比度（VEC-DIC）显微镜和高压电子显微镜（HVEM）研究了培养的鸡视网膜神经元的丝状伪足相互作用。使用HVEM检查固定细胞的整个安装表明，在较老的文化中的丝状伪足开发的外观，可能是预期的新生突触，成为扩大在其末端和积累类似突触囊泡的细胞器。VEC-DIC显微镜，用于观察丝状伪足在活细胞中的运动和粘附特性，显示丝状伪足尖端之间有特别高的亲和力。接触的丝状伪足通常会自我重新定位，这样它们就可以附着在一个尖端到尖端的位置，偶尔弯曲多达90度，以实现这一首选方向。相互作用的丝状伪足经常保持在一起，因为它们互相推或拉，一起横向移动，或者紧紧地伸展并经历强烈的振动运动。即使在丝状伪足之间存在明显的间隙时，也会发生这种连锁运动。用HVEM检查这些间隙显示连接并置膜的丝状结构。丝状连接直径为10-13 nm，长为30-100 nm。虽然尚未确定细丝反映了互连材料的天然构型，但这些结构似乎可能与丝状伪足尖端的强粘附行为有关。这些结构和功能特性的丝状伪足提示轴突生长和突触形成的可能意义进行了讨论。
Adhesive contacts made by filopodia of developing neurons are important in neurite growth and in the formation of synaptic junctions. In the present work, filopodial interactions of cultured chicken retina neurons were studied by using video-enhanced contrast, differential interference contrast (VEC-DIC) microscopy and the high-voltage electron microscope (HVEM). Use of the HVEM to examine whole mounts of fixed cells showed that filopodia in older cultures developed an appearance that might be expected of nascent synapses, becoming enlarged at their endings and accumulating organelles resembling synaptic vesicles. VEC-DIC microscopy, used to observe the motility and adhesive properties of filopodia in living cells, showed there was a particularly high affinity between filopodia tips. Contacting filopodia typically repositioned themselves so they could attach at a tip-to-tip position, occasionally bending as much as 90 degrees to achieve this preferred orientation. Interacting filopodia frequently remained together as they pushed or pulled on each other, moved laterally together, or stretched tightly and underwent intense vibratory movements. Such linked motility occurred even when apparent gaps existed between the filopodia. Examination of these gaps with the HVEM revealed filamentous structures linking the apposed membranes. The filamentous links were 10-13 nm in diameter and 30-100 nm long. Although it has not yet been established that the filaments reflect the native configuration of the interconnecting materials, the structures seem likely to be associated with the strongly adhesive behavior of the filopodial tips. The possible significance of these structural and functional properties of filopodia tips to axon growth and synapse formation is discussed.