Fei Y, Ma C H, Li Q, Song W, Tong W M, Niu Y M
Department of Pathology, Institute of Basic Medical Sciences Chinese Academy of Medical Science, School of Basic Medicine Peking Union Medical College, Beijing 100005, China.
Department of Biochemistry and Molecular Biology, State Key Laboratory of Medical Molecular Biology, Institute of Basic Medical Sciences Chinese Academy of Medical Sciences, School of Basic Medicine Peking Union Medical College, Beijing 100005, China.
Zhonghua Bing Li Xue Za Zhi. 2023 Jun 8;52(6):606-611. doi: 10.3760/cma.j.cn112151-20221117-00966.
To investigate the effects of RNA m6A demethylase ALKBH5 gene deficiency on cerebellar morphology and function in the aged mice, and to explore the role of ALKBH5 in cerebellar degeneration. Western blot was performed to detect the protein level of ALKBH5 in the cerebellum of wild-type mice of various ages. The expression of NeuN, Calbindin-D28K, MAP2, GFAP and other proteins in the cerebella of middle-aged (12-month-old) and aged (18-month-old) wild-type mice and ALKBH5 mice was examined using immunohistochemistry. The balance beam test and gait analysis were performed to test the balance ability and motor coordination of the mice. With aging of the mice, the expression of ALKBH5 in the cerebellum increased gradually in an age-dependent manner. In the aged mice, but not middle-aged mice, the body weight, whole brain weight and cerebellum weight of ALKBH5 mice decreased by 15%, 10% and 21%, respectively (<0.05). The expression of ALKBH5 in the Purkinje cells was much higher than that in other types of neural cells. Correspondingly, ALKBH5deficiency caused 40% reduction in the number of Purkinje cells, as well as the length and density of neuronal dendrites in the aged mice (<0.01). In addition, the time for the aged ALKBH5 mice to pass the balance beam was 70% longer than that of the wild type mice of the same age, with unstable gaits (<0.01). Gene deficiency of RNA m6A demethylase ALKBH5 causes cerebellar atrophy, Purkinje neuron loss and damage in the aged mice. These changes eventually affect mice's motor coordination and balance ability. These results suggest that imbalanced RNA m6A methylation may lead to neurodegenerative lesions in the cerebellum of mice.
为研究RNA m6A去甲基化酶ALKBH5基因缺陷对老年小鼠小脑形态和功能的影响，并探讨ALKBH5在小脑变性中的作用。采用蛋白质免疫印迹法检测不同年龄野生型小鼠小脑组织中ALKBH5蛋白水平。运用免疫组织化学方法检测中年（12月龄）和老年（18月龄）野生型小鼠及ALKBH5基因敲除小鼠小脑中NeuN、钙结合蛋白-D28K、微管相关蛋白2（MAP2）、胶质纤维酸性蛋白（GFAP）等蛋白的表达。通过平衡木试验和步态分析检测小鼠的平衡能力和运动协调性。随着小鼠年龄增长，小脑中ALKBH5的表达呈年龄依赖性逐渐增加。在老年小鼠而非中年小鼠中，ALKBH5基因敲除小鼠的体重、全脑重量和小脑重量分别下降了15%、10%和21%（P<0.05）。浦肯野细胞中ALKBH5的表达远高于其他类型神经细胞。相应地，ALKBH5基因缺陷导致老年小鼠浦肯野细胞数量减少40%，同时神经元树突长度和密度降低（P<0.01）。此外，老年ALKBH5基因敲除小鼠通过平衡木的时间比同年龄野生型小鼠长70%，步态不稳（P<0.01）。RNA m6A去甲基化酶ALKBH5基因缺陷导致老年小鼠小脑萎缩、浦肯野神经元丢失和损伤。这些变化最终影响小鼠的运动协调性和平衡能力。这些结果提示RNA m6A甲基化失衡可能导致小鼠小脑神经退行性病变。
Zotero 插件