Department of Physiological Science, University of Catania, Viale A. Doria 6, 95125 Catania, Italy.
Neuroscience. 2010 Nov 24;171(1):1-11. doi: 10.1016/j.neuroscience.2010.09.010. Epub 2010 Sep 17.
Connexin57 (Cx57) was previously reported in retinal cells but not in brain nerve cells. This occurrence was tested in this study, by searching for the expression of Cx57 RNA and protein transcripts during the postnatal development of the mouse CNS. Both the Cx57 RNA (investigated by reverse transcriptase-polymerase chain reaction (RT-PCR)) and the protein (Western-Blot and immunohistochemistry using a polyclonal antibody generated in chicken) transcripts were firstly expressed in the late postnatal development (P12). The expression of Cx57 in adult life (studied at P28, by in situ hybridization and immunohistochemical analysis) concerned few regions of the brain stem (inferior olive, lateral reticular nucleus and motor trigeminal nucleus), the cerebellum (Purkinje cells and cerebellar nuclei) and the spinal cord (alpha-motoneurons). Double immunohistochemical studies using the Cx57 antibody and antibodies, which specifically labelled neuronal nuclei (NeuN) and astrocyte cells glial fibrillary acidic protein (GFAP), showed the expression of Cx57 segregated in neuronal cells. The study also confirmed the expression of Cx57 in the horizontal cells of the retinal outer plexiform layer, reported in previous investigations. Given the expression of Cx57 in the cerebellum and pre-cerebellar nuclei, such as olivary and lateral reticular nuclei, a possible role of Cx57 was hypothesized in the electrical coupling of the cerebellum. This hypothesis was tested by searching for the expression of the Cx57 transcripts in the mouse cerebellum of the harmaline-tremor model. The up-regulation of the Cx57 transcripts reported in this model suggested a possible involvement of Cx57 in the electrotonic coupling of the cerebellar system.
间隙连接蛋白 57（Cx57）先前在视网膜细胞中报道过，但在脑神经元中未报道过。本研究通过在小鼠中枢神经系统的出生后发育过程中寻找 Cx57 RNA 和蛋白质转录本的表达来检验这一现象。Cx57 RNA（通过逆转录聚合酶链反应（RT-PCR）进行研究）和蛋白质（使用在鸡中生成的多克隆抗体进行 Western-Blot 和免疫组织化学）转录本首先在出生后晚期表达（P12）。Cx57 在成年期的表达（通过原位杂交和免疫组织化学分析在 P28 研究）涉及脑干的几个区域（下橄榄核、外侧网状核和运动三叉神经核）、小脑（浦肯野细胞和小脑核）和脊髓（α-运动神经元）。使用 Cx57 抗体和专门标记神经元核（NeuN）和星形胶质细胞胶质纤维酸性蛋白（GFAP）的抗体进行的双重免疫组织化学研究表明，Cx57 的表达在神经元细胞中分离。该研究还证实了 Cx57 在视网膜外丛状层的水平细胞中的表达，这在以前的研究中已有报道。鉴于 Cx57 在小脑和小脑前核（如橄榄核和外侧网状核）中的表达，假设 Cx57 在小脑的电耦联中可能发挥作用。通过在哈尔马汀震颤模型的小鼠小脑中寻找 Cx57 转录本的表达来检验这一假设。该模型中报告的 Cx57 转录本的上调表明 Cx57 可能参与小脑系统的电耦联。
