Question

Compare and contrast (in 100 words or less) the processes of Northern, Western and Southern Blotting.

Answer 1

Northern blot is used to detect and study specific RNA molecules from a mixture of different RNA. It involves the use of electrophoresis to separate RNA samples by size, and detection with a hybridization probe complementary to part of or the entire target sequence. Amino benzyloxymethyl filter paper membrane is used in this technique.

A Southern blot is used to detect the specific DNA sequence in DNA samples. It combines transfer of electrophoresis-separated DNA fragments to a filter membrane and subsequent fragment detection by probe hybridization. Nitrocellulose membrane is used in this technique.

Western blot is used to identify the presence of protein in a cellular extract or sample of mixture of proteins using the separation of proteins by SDS PAGE followed by the transfer of the protein gel into the nylon filter Membrane.