Abstract

The aim of the work was to study the intranuclear distribution of nucleophosmin (B23), coilin (p80), AgNOR proteins, and nonheme iron in the neurons of the human substantia nigra. Fragments of the human midbrain (n = 10) were shown to have no signs of neurodegeneration. The material was fixed in zinc–ethanol–formaldehyde, a special fixative that provides high preservation of antigenic determinants and tissue structures. This work revaled a new data on molecular and structural organization of the nucleoli of neurons in human substantia nigra. It was found that, in the nuclei of substantia nigra neurons, there is only one large nucleolus, and its size varies between individuals (from 4.2 ± 0.4 to 6.2 ± 0.6 μm in diameter). Nucleophosmin is concentrated solely in the nucleolus and is unevenly distributed in it. Cajal bodies found in the nucleus of most substantia nigra neurons are coiline-containing structures of round or oval shape and about 1 μm in size. Coilin accumulation has also been noted in numerous intranuclear microstructures, which significantly differ in their localization and morphological characteristics from typical Cajal bodies. AgNOR proteins are present in the substantia nigra neurons and are very variably distributed. Nonheme iron was detected in the nucleoli ofof some substantia nigra neurons. In some cases iron was concentrated in the giant fibrillar center (GFC). The data obtained will contribute to a clearer understanding of the role of nucleolar proteins in the functioning of dopaminergic neurons in the human brain and the determination of molecular sensors of nucleolar stress observed during neurodegeneration.

中文翻译：

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人类黑质黑质神经元中的核蛋白，螺旋蛋白和纯银（AgNOR）蛋白。

摘要

这项工作的目的是研究人类黑质神经元中核磷蛋白（B23），线圈蛋白（p80），AgNOR蛋白和非血红素铁的核内分布。人类中脑碎片（n = 10）显示没有神经变性的迹象。该材料固定在锌-乙醇-甲醛中，锌-乙醇-甲醛是一种特殊的固定剂，可高度保留抗原决定簇和组织结构。这项工作为人类黑质中神经元核仁的分子和结构组织提供了新的数据。结果发现，在黑质神经元核中，只有一个大的核仁，其大小因个体而异（直径从4.2±0.4到6.2±0.6μm）。核蛋白仅集中在核仁中，并且分布不均匀。在大多数黑质神经元细胞核中发现的卡哈尔虫体是含有卷曲素的圆形或椭圆形结构，大小约为1μm。在许多核内微结构中也已注意到螺旋蛋白的积聚，它们的定位和形态特征与典型的Cajal体明显不同。AgNOR蛋白存在于黑质神经元中，并且分布非常不同。在一些黑质神经元的核仁中检测到非血红素铁。在某些情况下，铁集中在巨大的原纤维中心（GFC）中。所获得的数据将有助于更清楚地了解核仁蛋白在人脑中多巴胺能神经元的功能中的作用，以及确定神经变性期间观察到的核仁应激的分子传感器。