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Studying DNA and RNA
Real-Time RT-PCR for Gene Expression Tracking
Description
Real-time RT-PCR tracks gene expression by measuring how much target DNA is made during PCR. It starts with mRNA, which is converted into complementary DNA, or cDNA, by an enzyme called reverse transcriptase. The cDNA is then amplified by PCR so the target sequence can be measured.
This method ca...
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Transcript
实时反转录-聚合酶链式反应(Real-time RT-PCR)可在反应进行过程中定量目标RNA。
首先,逆转录酶将RNA转录为互补的DNA(cDNA)。RNase H 降解原始的RNA,仅留下附着在cDNA上的短片段引物。
随后,DNA聚合酶会合成一条互补链。
随后可以使用PCR对特定片段进行靶向扩增,以指数级复制这些片段。每个循环开始时,在高温下使两条链分离。互补的寡核苷酸引物随后退火至每条cDNA链,并由DNA聚合酶延伸。
可以使用两种不同的基于荧光的检测方法之一来定量DNA。其中一种方法使用仅在与双链DNA结合时才会发出荧光的染料。
染料与DNA结合,此时原始链与新合成的互补链配对。每个PCR循环结束时,适当...
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