Muscle creatine kinase sequence elements regulating skeletal and cardiac muscle expression in transgenic mice
Muscle creatine kinase sequence elements regulating skeletal and cardiac muscle expression in transgenic mice
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DOI：
10.1128/mcb.9.8.3393-3399.1989
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发表时间：
1989-08
影响因子：
5.3
通讯作者：
Jane E. Johnson;B. Wold;S. Hauschka
中科院分区：
文献类型：
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作者：
Jane E. Johnson;B. Wold;S. Hauschka
肌肌酸激酶（MCK）仅在骨骼肌和心肌组织中高水平表达。以前在骨骼肌成肌细胞和成纤维细胞的体外转染研究已经确定了两个MCK增强子元件和一个近端启动子元件，其中每一个只在分化的骨骼肌中表现出表达。在这项研究中，我们已经确定了几个地区的小鼠MCK基因是负责组织特异性表达的转基因小鼠。含有MCK 5'序列的3，300个核苷酸的融合基因在骨骼肌中表现出氯霉素乙酰转移酶活性水平，比其他非肌肉组织（如肾、肝和脾）高10（4）倍以上。心肌中的表达也比这些非肌肉组织中的表达高2至3个数量级。从核苷酸-3300的进行性5'缺失导致转基因的表达降低，并且其中之一导致相对于骨骼肌中的表达，在心脏组织中的表达优先降低。在分析的两个增强子序列中，只有一个在骨骼肌和心肌中指导高水平表达。另一个增强子仅在骨骼肌中激活表达。这些数据揭示了一组复杂的顺式作用序列，这些序列对骨骼肌和心肌中的MCK表达具有不同的影响。
Muscle creatine kinase (MCK) is expressed at high levels only in skeletal and cardiac muscle tissues. Previous in vitro transfection studies of skeletal muscle myoblasts and fibroblasts had identified two MCK enhancer elements and one proximal promoter element, each of which exhibited expression only in differentiated skeletal muscle. In this study, we have identified several regions of the mouse MCK gene that are responsible for tissue-specific expression in transgenic mice. A fusion gene containing 3,300 nucleotides of MCK 5' sequence exhibited chloramphenicol acetyltransferase activity levels that were more than 10(4)-fold higher in skeletal muscle than in other, nonmuscle tissues such as kidney, liver, and spleen. Expression in cardiac muscle was also greater than in these nonmuscle tissues by 2 to 3 orders of magnitude. Progressive 5' deletions from nucleotide -3300 resulted in reduced expression of the transgene, and one of these resulted in a preferential decrease in expression in cardiac tissue relative to that in skeletal muscle. Of the two enhancer sequences analyzed, only one directed high-level expression in both skeletal and cardiac muscle. The other enhancer activated expression only in skeletal muscle. These data reveal a complex set of cis-acting sequences that have differential effects on MCK expression in skeletal and cardiac muscle.