核酸的反意义和抗原特性
J C Hanvey1, N J Peffer, J E Bisi
1Department of Cell Biology, Glaxo Inc. Research Institute, Research Triangle Park, NC 27709.
概括
核酸 (PNA) 可以准特定的DNA和RNA序列. PNAs有效地抑制转录,逆转录和翻译,证明了它们作为基因表达调节器的潜力.
科学领域:
- 分子生物学分子生物学
- 橄核酸的化学成分
- 基因规则 基因规则
背景情况:
- 核酸 (PNA) 是DNA模仿物,具有独特的聚胺骨干.
- PNAs对互补的核酸序列表现出强大的结合亲和力.
- PNAs可以侵入双重DNA,形成D环并取代DNA链.
研究的目的:
- 调查PNAs抑制核酸模板过程的能力.
- 评估PNA结合对转录,逆转录和翻译的特定部位的影响.
- 评估PNAs在细胞系统中针对性基因沉默的潜力.
主要方法:
- 各种PNA序列 (T10,15-mer,20-mer) 的合成和应用.
- 使用无G磁带进行转录终止的测试.
- 实验室内研究PNA-RNA异重复组的形成及其对逆转录和翻译的影响.
- 在SV40大T抗原表达细胞中进行核微注射实验.
主要成果:
- PNA与转录的DNA链结合,导致90-100%的特定位点转录终止.
- PNA与非转录的链结合的抑制率低于50%.
- PNA与RNA结合导致逆转录和体外翻译的局部特定终止.
- 针对T Ag mRNA的PNAs微注射以依赖序列的方式抑制了T Ag表达.
结论:
- PNAs是转录,逆转录和翻译的强有力的抑制剂.
- PNA结合部位和链的方向显著影响抑制疗效.
- 针对特定mRNA的PNAs可以有效地抑制基因表达,突出显示它们的治疗潜力.
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