Conditional transgene expression in the heart
Conditional transgene expression in the heart
复制标题
DOI：
10.1161/01.res.79.4.691
复制
发表时间：
1996-10-01
影响因子：
20.1
通讯作者：
Fishman, GI
中科院分区：
文献类型：
--
作者：
Yu, ZH;Redfern, CS;Fishman, GI
条件转基因表达是研究体内复杂生物系统的潜在有用方法。我们最近证明，四环素响应启动子可用于在转基因小鼠中实现靶基因的调节、心脏特异性表达。为了更全面地定义与心脏中四环素调节的基因表达相关的定量和空间参数，我们将携带萤火虫荧光素酶或核定位细菌lacZ靶基因的转基因小鼠与在大鼠α-肌球蛋白重链基因的2.9kb 5'侧翼序列的调节控制下表达四环素控制的反式激活子（tTA）的菌株进行杂交。与仅携带荧光素酶报告基因的小鼠相比，双转基因小鼠心脏中的荧光素酶活性提高了近 300 倍。在所检查的任何其他组织中均未观察到显着的反式激活。含有 lacZ 报告基因的二元转基因在整个心脏中显示出大量的 β-半乳糖苷酶活性，但各个心肌细胞的反应是异质的。对于这两个报告基因，四环素处理完全抑制了 tTA 依赖性反式激活。这些数据为研究的性质提供了重要的见解，可以使用心脏中的四环素调节的基因表达系统成功地解决这些研究。
Conditional transgene expression is a potentially useful approach to investigate complex biological systems in vivo. We recently demonstrated that tetracycline-responsive promoters could be employed to achieve regulated, cardiac-specific expression of target genes in transgenic mice. To more fully define the quantitative and spatial parameters associated with tetracycline-regulated gene expression in the heart, we crossed transgenic mice harboring either a firefly luciferase or a nuclear-localized bacterial lacZ target gene with strains expressing a tetracycline-controlled transactivator (tTA) under the regulatory control of 2.9 kb of 5' flanking sequence from the rat alpha-myosin heavy chain gene. Luciferase activity was induced nearly 300-fold in the hearts of binary-transgenic mice compared with mice carrying only the luciferase reporter gene. No significant transactivation was observed in any other tissues examined. Binary transgenics harboring the lacZ reporter gene showed substantial beta-galactosidase activity throughout the heart, but the response of individual cardiac myocytes was heterogeneous. For both reporter genes, tetracycline treatment fully repressed tTA-dependent transactivation. These data provide important insights into the nature of studies that can be successfully addressed using the tetracycline-regulated gene expression system in the heart.