DEVELOPMENTAL PREDETERMINATION OF THE STRUCTURAL AND MOLECULAR-POLARIZATION OF PHOTORECEPTOR CELLS
DEVELOPMENTAL PREDETERMINATION OF THE STRUCTURAL AND MOLECULAR-POLARIZATION OF PHOTORECEPTOR CELLS
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DOI：
10.1016/0012-1606(86)90319-2
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发表时间：
1986-10-01
影响因子：
2.7
通讯作者：
ADLER, R
中科院分区：
文献类型：
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作者：
ADLER, R
胚胎视神经杯表面同质的神经上皮分化为不同的细胞类型，如光感受器、胶质细胞和各种神经元亚群，其机制尚不清楚。该领域仍未解决的问题包括“指导性”事件的时间和作用机制，这些事件指导每个神经上皮细胞经历发育成特定视网膜细胞类型所需的表型变化序列。本实验室正在研究其中的一些问题，使用在明显的感光细胞分化开始之前获得的分离的神经视网膜细胞，在缺乏胶质细胞和色素上皮的情况下以低密度发育。培养最初是一个形态均匀的群体无过程，圆形细胞。一些细胞在体外培养的第一周内保持这种形态，而另一些细胞则发育成光感受器或多极神经元。像在体内一样，光感受器拉长，变得非常不对称，具有沿其纵轴有序排列的特征性隔室（外节状突起、内节、细胞体和特征性的短而单的神经突）。细胞极化也可以在视蛋白免疫反应物质和一些细胞骨架元件的分布中观察到。因此，胚胎视网膜中存在的某些前体细胞似乎被编程为分化为光感受器，即使在没有与其他视网膜细胞接触的情况下发育。然而，与视网膜/色素上皮复合体的其他成分的相互作用可能是确保最终光感受器成熟所必需的，包括富含视蛋白的外段过程的进一步生长。
Through mechanisms still unknown, the apparently homogeneous neuroepithelium of the embryonic optic cup differentiates into such divergent cell types as photoreceptors, glia, and various subsets of neurons. Questions that still remain unanswered in this field include the timing and mechanism of action of the "instructive" events directing each neuroepithelial cell to undergo the sequence of phenotypic changes necessary to develop into a specific retinal cell type. This laboratory is investigating some of these questions using cultures in which dissociated neural retina cells, obtained before the onset of overt photoreceptor differentiation, develop at low density in the absence of glia and pigment epithelium. The cultures initially are a morphologically homogeneous population of process-free, round cells. Some cells retain this morphology throughout the first week in vitro, while others develop either as photoreceptors or as multipolar neurons. Photoreceptors elongate and become very asymmetric as they do in vivo, with characteristic compartments orderly arranged along their longitudinal axis (an outer segment-like process, inner segment, cell body, and a characteristically short, single neurite). Cell polarization can also be observed in the distribution of opsin immunoreactive materials and some cytoskeletal elements. Thus, certain precursor cells present in the embryonic retina seem to be programmed to differentiate into photoreceptors even when developing in the absence of contacts with other retinal cells. However, interactions with other constituents of the retina/pigment epithelium complex are probably necessary to ensure final photoreceptor maturation, including further growth of the opsin-rich outer segment process.