Practice question

Technique capable of detecting both DNA and RNA targets through hybridization is often described as Southern-Northern combined approach. Standard Southern blotting uses DNA probes to detect DNA fragments, while Northern uses similar probes for RNA. By preparing membrane containing both nucleic acid species or by sequentially hybridizing same blot under conditions allowing DNA-DNA and DNA-RNA duplex formation, one can determine whether gene sequence present and transcribed. South-Western specifically detects DNA-protein interactions after protein renaturation, Western detects proteins via antibodies, and ELISA is antibody-based plate assay incapable of nucleic acid hybridization, lacking dual hybridization ability.