✦ Initially, the purified sample is loaded onto an agarose gel and electrophoresed, causing the sample to separate into bands. It allows one to study restricted (cut) DNA fragments, changes in the sequence, and its relative quantity across different samples. Southern blotting is used to detect and study specific DNA sequences. It allows the investigator to determine the molecular weight of mRNA, and also to determine the relative quantity of mRNA (gene expression) across different samples. Northern blotting is a technique used to detect and study specific RNA molecules from a mixture of different RNA, all isolated from a particular tissue or cell type. Northern and Southern Blotting Techniques The intensity of the resultant dye or fluorescence will indicate the specificity of the binding along with other characteristics such as copy number, gene expression, etc. This change in binding affinity will be visualized upon secondary hybridization with a labeled probe. Any change in the sample sequences will lead to the probes not binding or binding non-specifically. PrincipleĪll blotting techniques are based on the same principle of specific base pairing of the probe sequences to the sequences immobilized on the membrane. The purpose of each technique may be different, but all share the same principle and methodology, with a few minor deviations and modifications. Southern blotting is used in case of DNA, Northern blotting in case of RNA, Western blotting in case of proteins, and Eastern blotting in case of post-translational modifications of proteins. In molecular biology and genetics, various blotting techniques are employed to detect and study changing levels of proteins, DNA, or RNA, and also to study the interactions occurring between them. Subsequent blotting techniques (Northern blotting, Western blotting, etc.), which are based on the same principle, are named eponymously. Southern, a British biologist who developed this technique. BiologyWise explains the nature and principle of these techniques, and compares the differences between them.
Northern and Southern blotting are techniques used in molecular biology, which are used to detect macromolecular changes related to the DNA.
0 kommentar(er)
