cis-acting elements responsible for muscle-specific expression of the myosin heavy chain beta gene.
cis-acting elements responsible for muscle-specific expression of the myosin heavy chain beta gene.
复制标题
负责肌球蛋白重链β基因的肌肉特异性表达的顺式作用元件。
DOI：
10.1093/nar/20.7.1793
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发表时间：
1992
影响因子：
14.9
通讯作者：
Zak,R
中科院分区：
文献类型：
--
作者：
Shimizu,N;Prior,G;Umeda,PK;Zak,R
兔肌球蛋白重链(HC) β基因的5'侧翼区域从帽位向上游延伸295 bp，提供肌肉特异性的交叉活性。在这项研究中，我们已经确定并功能表征了调节该区域肌肉特异性表达的类作用元件。通过使用- 295 bp之间的连接扫描（LS）突变体和假定的TATA box，我们发现了转录所需的五个不同的正顺式作用序列：元件a，序列在- 276和- 263之间，其中包含一个假定的倒置方向的M-CAT基序；B，−207 ~−180之间的序列；C，−136 ~−127之间的序列；D，−91 ~−80之间的序列；E是−28的TATA共识序列。含有A和B元件的片段在分化的肌肉细胞中显著增强了由异源启动子驱动的氯霉素乙酰转移酶（CAT）基因的表达，而单独含有A或B元件的片段在肌肉细胞和非肌肉细胞中几乎没有或没有影响。因此，这两个因素似乎在决定高水平的肌肉和阶段特异性表达方面协同作用。与典型的增强子元素不同，该区域以方向依赖的方式起作用。相反，含有C和D元素的片段在肌肉细胞和非肌肉细胞中以不依赖于方向的方式激活异质启动子。
The 5' flanking region of the rabbit myosin heavy chain (HC) β gene extending 295 bp upstream from the cap site provides muscle-specific transciiptional activity. In this study, we have identified and functionally characterized cls-acting elements that regulate the muscle-specific expression within this region. By using linker-scanner (LS) mutants between - 295 bp and a putative TATA box, we found five distinct positive cis-acting sequences necessary for transcription: element A, the sequences between −276 and −263, which contains a putative M-CAT motif in an inverted orientation; B, the sequences between −207 and −180; C, the sequences between −136 and −127; D, the sequences between −91 and −80; and E, a TATA consensus sequence at −28. The fragment containing both A and B elements dramatically enhanced the expression of the chloramphenicol acetyltransferase (CAT) gene driven by a heteroiogous promoter in differentiated muscle cells, whereas fragments containing either A or B elements alone had little or no effect in either muscle or nonmuscle cells. Therefore, these two elements appear to act cooperatively in determining a high level of muscle- and stage-specific expression. Unlike the typical enhancer element, this region functions in an orientation-dependent manner. In contrast, the fragment containing C and D elements activates the heteroiogous promoter in both muscle and nonmuscle cells in an orientation-independent manner.