Varga Balázs, Markó Károly, Hádinger Nóra, Jelitai Márta, Demeter Kornél, Tihanyi Károly, Vas Adám, Madarász Emília
Institute of Experimental Medicine of Hungarian Academy of Sciences, Budapest, Hungary.
Neurosci Lett. 2009 Oct 25;462(3):257-62. doi: 10.1016/j.neulet.2009.06.051. Epub 2009 Jun 21.
Translocator protein 18 kDa, the peripheral benzodiazepine receptor by its earlier name, is a mitochondrial membrane protein associated with the mitochondrial permeability pore. While the function of the protein is not properly understood, it is known to play roles in necrotic and apoptotic processes of the neural tissue. In the healthy adult brain, TSPO expression is restricted to glial cells. In developing or damaged neural regions, however, TSPO appears in differentiating/regenerating neurons. Using immunocytochemical, molecular biological and cell biological techniques, we demonstrate that TSPO mRNA and protein, while missing from mature neurons, are present in neural stem cells and also in postmitotic neuronal precursors. Investigating some distinct stages of in vitro differentiation of NE-4C neural stem cells, TSPO 18 kDa was found to be repressed in a relatively late phase of neuron formation, when mature neuron-specific features appear. This timing indicates that mitochondria in fully developed neurons display specific characteristics and provides an additional marker for characterising neuronal differentiation.
18 kDa转位蛋白，其曾用名是外周苯二氮䓬受体，是一种与线粒体通透性转换孔相关的线粒体膜蛋白。虽然该蛋白的功能尚未完全明确，但已知它在神经组织的坏死和凋亡过程中发挥作用。在健康的成人大脑中，TSPO的表达仅限于神经胶质细胞。然而，在发育中的或受损的神经区域，TSPO出现在分化/再生的神经元中。我们运用免疫细胞化学、分子生物学和细胞生物学技术证明，TSPO mRNA和蛋白在成熟神经元中缺失，但存在于神经干细胞以及有丝分裂后的神经元前体细胞中。在研究NE-4C神经干细胞体外分化的一些不同阶段时，发现18 kDa的TSPO在神经元形成的相对晚期阶段受到抑制，此时成熟神经元的特异性特征开始出现。这一时期表明，完全发育的神经元中的线粒体呈现出特定特征，并为表征神经元分化提供了一个额外的标志物。
