Branched DNA

In biology, branched DNA analysis is the analysis of amplification, (as opposed to target amplification assays, such as a) signal used for the detection of nucleic acid molecules. On the base, branched DNA analysis begins hard and other media plate (for example, bars of plastic) in the. Dish is studded (or chain) small single-stranded DNA molecule in the air “stick” that. I call a molecular DNA “capture probe” of these. Then, DNA molecules are inserted in the “extension”. The “extender” each of which can “hang” in the air and one that hybridizes two regions, the DNA molecule for detection. There are two purposes of expansion. First, create a space available most of the target DNA molecule to which it is linked, on the other hand, can be adapted to the detection of target DNA molecules differing ease of analysis.

Branched DNA illustration

After the capture extender molecules are present, they are hybridized, it is possible that the addition of probe. The target molecules in the sample bind to the extension of the molecule. So we have a dotted foundation capture probe that hybridizes to hybridize the extender probe to a target molecule in order.  At this time, signal amplification is performed. It is said that “label extension” DNA molecule, that there is (extension of the first) two fields. Extension of the label, hybridize to the molecule “preamplifier” the target. There are two areas preamplifier molecule. First, bind the label extension, the other part is connected to the amplifier molecule. Molecules such as the amplifier circuit of the oligonucleotide associated with the enzyme alkaline phosphatase such.

I will occur if the additional space does not exist in the other end of the double-stranded DNA of additional fray in DNA. However, if that contains a contiguous area that can be chain third DNA is introduced to hybridize to problem areas in front of the two heavy chain might branched DNA occurs. In the simplest example of branched DNA, INCLUDING BUT NOT the DNA complex of the three branches and several additional fields alone can incorporate. Branched DNA, please refer to can be used in the field of nanotechnology to build the geometry, the use of the following techniques.

Analysis can be used for detection and quantification of many types of DNA target or RNA. In the assay, branched DNA was mixed with the test sample. Detection does not require a pre-amp of the nucleic acid to be detected was performed using the method of non-radioactive. In the analysis, I rely entirely on hybridization. Enzymes are used to indicate the degree of hybridization, but is not used to manipulate nucleic acids. Therefore, it is possible to detect without PCR and / or (for RNA) reverse transcription step of the nucleic acid a small amount, and quantified. It is labor intensive, unlike amount of RN RNase protection assays or Northern blotting to make a large number of samples is difficult, the analysis can be controlled, as “Analysis of High Performance“. After reverse transcription of RNA to DNA, an important performance Another technique that is used for the determination of specific RNA molecules is a quantitative PCR.

Single-stranded DNA molecule short of some of the other (oligonucleotide), I used to branched DNA analysis. Capture the extender oligonucleotide binding to the solid support for the immobilization and target nucleic acid, I will capture. I detecting a target nucleic acid immobilized branched DNA and labeled oligonucleotides. Reducing the false-positive, immobilization of the target on the solid support is facilitated extensive cleaning. Target enzyme (eg, alkaline phosphatase) and can be detected by the branched DNA which binds to after binding to a solid support. Bind specifically to the nucleic acid sample by hybridization of a specific area that is not occupied by the capture of the hybrid branched DNA. Branch of the DNA, thus enabling decoration very dense and DNA enzyme that is essential for high-sensitivity analysis of [edit]. The enzyme catalyzes the reaction with the substrate to produce a (detected by the luminometer) light. The amount of light emitted, thereby increasing the amount of a particular nucleic acid in a sample. Design of branched DNA, and method for hybridizing to the nucleic acid to be examined is different between generations of different analysis bDNA. Despite the fact that the starting material is pre-amplified, bDNA assays, can be found in the blood 100 copies per 1ml HIV-RNA below.

It must be designed nucleic individual chains to come together in a desired structure reasonably DNA nanostructures. Usually, begins by determining the functionality.Then target or desired structure, secondary structure overall target complexes is the position of the nucleic acid chain moiety of these threads that structures that are bound to each other, this process is defined by specifying. The final step is a design basic structure is a specification of the nucleotide sequence of each of the actual nucleic acid strand.