Which technique identifies a specific DNA sequence using a radiolabelled DNA probe ?
Southern Blotting
The blotting techniques are named for the molecule they detect, and the one that detects DNA with a labelled DNA probe is Southern blotting, devised by Edwin Southern in 1975.
The steps are: digest the DNA with restriction enzymes, separate the fragments by size on an agarose gel, denature them into single strands, transfer them onto a nitrocellulose or nylon membrane, and then hybridise with a radiolabelled complementary probe. Autoradiography shows a band exactly where the probe has bound, identifying the sequence sought.
The related methods target other molecules. Northern blotting detects RNA, Western blotting detects proteins using antibodies rather than nucleic-acid probes, and Eastern blotting is used for post-translational modifications of proteins.
Hence, the answer is Southern Blotting.
Important Questions from Biotechnology
Given below are two statements :
Statement I:
Restriction endonucleases are enzymes naturally found in bacteria, where they protect the host cell by degrading foreign DNA.
Statement II:
All restriction endonucleases cut both strands of the DNA molecule at the exact same position, producing 'blunt ends'.
In the light of the above statements, choose the most appropriate answer from the options given below:
'Golden rice' variety of rice shows:
First restriction endonuclease enzyme was-
The main technique involved in agricultural biotechnology is
Consider the following statements :
Statement I: Bacillus thuringiensis (Bt) is a microbial pesticide.
Statement II: Beaveria bassiana is a fungus used as a pesticide.
