Murine cytomegalovirus immediate-early promoter directs astrocyte-specific expression in transgenic mice
Murine cytomegalovirus immediate-early promoter directs astrocyte-specific expression in transgenic mice
复制标题
DOI：
10.1016/s0002-9440(10)65320-5
复制
发表时间：
1999-03-01
影响因子：
6
通讯作者：
Tsutsui, Y
中科院分区：
文献类型：
--
作者：
Aiba-Masago, S;Baba, S;Tsutsui, Y
小鼠巨细胞病毒（MCMV）可引起自然宿主的急性、潜伏和持续感染，被用作人巨细胞病毒（HCMV）感染的动物模型。MCMV立即早期（IE）基因的转录是早期和晚期基因表达所必需的，并且依赖于宿主细胞转录因子。在用主要IE（MIE）增强子/启动子产生的转基因小鼠中分析MCMV IE启动子的细胞类型特异性表达活性，所述主要IE（MIE）增强子/启动子涉及与报告基因lacZ连接的核苷酸-1343至-6（1338 bp）。在脑、肾、胃和骨骼肌中观察到不同的表达。在唾液腺和胰腺的部分实质细胞中观察到弱表达，在肺、肠或免疫和造血器官如胸腺、脾、淋巴结和骨髓中几乎未检测到表达。表达阳性的器官谱比先前报道的HCMV MIE启动子-lacZ转基因小鼠的器官谱窄，并且表现出更大程度的细胞类型特异性。有趣的是，通过结合β-半乳糖苷酶（β-Gal）表达，在转基因小鼠的脑和原代神经胶质细胞培养物中观察到转基因的星形胶质细胞特异性表达。免疫染色用于细胞标记物。然而，转基因在神经元、少突胶质细胞、小胶质细胞或内皮细胞中不表达。此外，MCMV感染或加入钙离子载体显著刺激神经胶质细胞培养物中的β-Gal表达。这些观察结果表明MCMV IE启动子的表达活性是严格的细胞类型特异性的，特别是在脑中的星形胶质细胞特异性的。这种特定的活动模式与人类自然HCMV感染相似。
Murine cytomegalovirus (MCMV), which causes acute, latent, and persistent infection of the natural host, is used as an animal model of human cytomegalovirus (HCMV) Infection. Transcription of MCMV immediate-early (IE) genes is required for expression of the early and late genes and is dependent on host cell transcription factors. Cell-type-specific expression activity of the MCMV IE promoter was analyzed in transgenic mice generated with the major IE (MIE) enhancer/promoter involving nucleotides -1343 to -6 (1338 bp) connected to the reporter gene lacZ. Distinct expression was observed in the brain, kidneys, stomach, and skeletal muscles. Weak expression was observed in a portion of the parenchymal cells of the salivary glands and pancreas, and expression was hardly detected in the lungs, Intestine, or immune and hematopoietic organs such as the thymus, spleen, lymph nodes, and bone marrow. The spectrum of organs positive for expression was narrower than that of the HCMV MIE promoter-lacZ transgenic mice reported previously and showed a greater degree of cell-type specificity. Interestingly, astrocyte-specific expression of the transgene was observed in the brain and primary glial cultures from the transgenic mice by combination of beta-galactosidase (beta-Gal) expression and. immunostaining for cell markers. However, the transgene was not expressed in neurons, oligodendroglia, microglia, or endothelial cells. Furthermore, the beta-Gal expression in glial cultures was stimulated significantly by MCMV infection or by addition of calcium ionophore. These observations indicated that expression activity of the MCMV IE promoter Is strictly cell-type specific, especially astrocyte-specific in the brain. This specific pattern of activity is similar to that of natural HCMV Infection in humans.