肽核酸在分子生物学技术中的应用

肽核酸(PNA)作为一种人工合成的核酸类似物,以中性的肽链酰胺2-氨基乙基甘氨酸键取代了DNA中的戊糖磷酸二酯键骨架,其余部分与DNA相同。PNA可通过Watson-Crick碱基配对的形式识别并结合DNA或RNA序列,形成稳定的双螺旋结构。与传统的DNA或RNA相比,PNA具有生物学稳定性高、杂交特异性强、杂合体的稳定性高和杂交速度快等明显优点,使PNA具有良好的物理化学性质和生物学特性,在检测目的核酸序列中单碱基突变、PCR基因分子诊断与检测、荧光原位杂交定量分析、基因芯片和生物传感器技术等调控水平和临床应用上有自己的特点。简要综述了近年来肽核酸在上述分子生物学技术中的运用以及应用前景的展望。

Application of Peptide Nucleic Acid in Molecular Biotechnology

Peptide nucleic acid (PNA) is a nucleic acid mimic in which the deoxyribose phosphate backbone has been replaced by a pseudo-peptide polymer to which the nucleobases are linked. PNA forms complexes with DNA following the Watson-Crick base-pairing rules. The PNA-DNA complexes exhibited high thermal stability and mismatch sensitivity. The high stability of these hybrids has been explained by the absence of negative charges along the PNA backbone. Furthermore, PNA is resistant to biological degradation and can bind complementary RNA or DNA sequences with extraordinary high affinity and specificity. PNA possesses many of the properties desired for a good antisense agent or antigene drugs, such as the detection of a single base mutate in nucleic acids, the diagnosis and detection by PCR molecular beacon, quantitative analysis of fluorescence in situ hybridization, genechip and biosensor technology and so on. Thus, the above-mentioned applications of PNA in molecular biotechnology in recent years and the prospect of its application were summarized.