The technique used for separation and detection of RNA is which one of the following?
**Core Concept**
Northern blotting is a laboratory technique used for the separation and detection of RNA molecules. It is a variant of the Southern blotting technique, which is used for DNA. Northern blotting involves electrophoresis of RNA samples, transfer of the RNA to a membrane, and hybridization with labeled probes to detect specific RNA sequences.
**Why the Correct Answer is Right**
The correct answer is Northern blotting because it is the technique specifically designed for RNA detection. Northern blotting involves the use of formaldehyde to denature the RNA and prevent secondary structure formation, followed by electrophoresis in a denaturing agarose gel. The RNA is then transferred to a membrane, where it is hybridized with a labeled probe complementary to the target RNA sequence. This allows for the detection and quantification of specific RNA molecules.
**Why Each Wrong Option is Incorrect**
**Option A:** Western blotting is a technique used for the detection of proteins, not RNA. It involves electrophoresis of protein samples, transfer of the proteins to a membrane, and hybridization with labeled antibodies to detect specific protein sequences.
**Option B:** PCR (Polymerase Chain Reaction) is a technique used for amplification of DNA or RNA sequences, but it is not a method for separation and detection of RNA.
**Option C:** Southern blotting is a technique used for the detection of DNA, not RNA. It involves electrophoresis of DNA samples, transfer of the DNA to a membrane, and hybridization with labeled probes to detect specific DNA sequences.
**Clinical Pearl / High-Yield Fact**
Northern blotting is a useful technique for studying gene expression and regulation, particularly in the context of disease. It can be used to detect changes in RNA levels in response to various stimuli, such as hormones or growth factors.
**Correct Answer: C. Southern blotting is a technique used for the detection of DNA, not RNA.