Thekey differencebetween DNA and RNA probes is thatcomplemen DNA探针的DNA片段tary to targetnucleotidesequences while RNA probes are stretches of single-stranded RNA which are complementarynucleic acidsequences of target sequences.
探针是人为合成的DNA或RNA的短序列，可以放射性地或非放射性分子标记。它可以具有100至1000个基础的长度。探针可用于检测与探针序列互补的靶核苷酸序列。一旦添加，探针就会与互补序列或目标序列杂交，并使探针可见以识别目标序列，因为它具有放射性。探针是许多微生物和分子区域中的重要分子工具，例如遗传疾病的检测，病毒学，法医病理学，亲子鉴定，在DNA fingerprinting,RFLP, molecular cytogenetics,in situhybridization, etc.
1.Overview and Key Difference
2.What are DNA Probes
3.What are RNA Probes
5.并排比较 - 表格形式的DNA与RNA探针
What are DNA Probes?
DNA probes are single-stranded stretches of DNA. They can be used to detect the presence of complementary nucleic acid sequences (target sequences) byhybridization. Once a DNA probe hybridized with its complementary sequence, it forms a double-stranded hybrid. In order to detect them, DNA probes are generally labelled with radioisotopes, biotin, epitopes or fluorophores. The DNA probes labelled with biotin can be detected with streptavidin-labelled alkaline phosphatase by a number of enzymatic and chemical methods.
The nucleotide sequence of the DNA probe is known. They are short sequences with a length of 100 to 1000 base pairs. Long DNA probes can be generated by recombinant DNA technology. They can also be generated by PCR and cloning. In clinical microbiology laboratories, DNA probes are readily available for the rapid diagnosis of infectious diseases.
What are RNA Probes?
RNA probes are single-stranded stretches of RNA. They are complementary sequences to target sequences in the sample. They are commonly synthesized with the RNA polymerases from bacteriophages SP6, T7, or T3 by体外transcription of DNA. Long RNA probes can be generated by体外transcription from linearized plasmid DNA. Generally, RNA probes bind strongly and tighter to their complementary sequences than DNA probes. Similar to DNA probes, RNA probes also can be labelled while they are being transcribed.
What are the Similarities Between DNA and RNA Probes?
- Both are artificially designed and synthesized.
- They have a strong affinity towards a specific DNA or RNA target sequence.
- 它们用于各种印迹和in situhybridization techniques for the detection of target nucleic acid sequences.
- Both types of probes can be hybridized with their complementary sequences.
What is the Difference Between DNA and RNA Probes?
DNA probe is a short stretch of DNA which is complementary to the target sequence. On the other hand, the RNA probe is a short single-stranded stretch of RNA complementary to the target sequence. Thus, this is the key difference between DNA and RNA probes. Furthermore, DNA probes contain A, T, C and G while RNA probes contain A, U, C and G.
Moreover, a further difference between DNA and RNA probes is their thermodynamic stability. RNA probes show greater thermodynamic stability compared to DNA probes.
Below infographic tabulates the important differences between DNA and RNA probes.
概括– DNA vs RNA Probes
A probe is a small fragment of DNA or RNA used to detect the presence of a specific sequence in the sample of DNA or RNA by molecular hybridization. DNA probes are short single-stranded DNA fragments while RNA probes are short single-stranded RNA sequences. They are known sequences. Thermodynamic stability is greater in RNA probes than DNA probes. RNA probes bind tightly to their complementary sequences than DNA probes bind. Thus, this summarizes the difference between DNA and RNA probes.
1.“ RNA探针。”RNA探针 - 概述|ScienceDirect主题，Available here.
1.“ Lightcycler探针”(CC BY-SA 3.0)viaCommons Wikimedia