Final answer:
To search the TSA database, using the Complementary DNA (cDNA) sequence is most appropriate because it represents the coding sequence without introns. The cDNA is used for verification purposes and for creating a probe to screen a gene in a genomic library. Techniques such as Southern Blotting are applied to isolate specific fragments for further investigation or use in biotechnology.
Step-by-step explanation:
When it comes to searching the TSA database, the correct option to use would be Option 3: Complementary DNA (cDNA) sequence. The cDNA represents the exact sequence of a cloned plasmid DNA that encodes a protein, without introns that are present in genomic DNA. Once you have cloned the relevant plasmid and isolated its DNA, you would typically sequence it to obtain the cDNA. This cDNA sequence can then be used to not only verify that you have the correct protein coding sequence but also for the creation of a DNA probe or to screen a gene in a genomic library. Amino acid sequences and protein sequences are not directly searchable in a nucleotide database like TSA. Searching with genomic DNA could be less specific due to the presence of non-coding regions. The cDNA can be made radioactive or fluorescent as a probe for further applications such as finding the gene within a genomic clone or for forensic comparisons.
Through techniques such as Southern Blotting and the usage of a DNA probe, it is possible to isolate specific DNA fragments containing the gene of interest. Similarity in sequences also plays a crucial role in forensic genetics, where it is used to establish a match between DNA samples. With a known sequence, researchers can clone, amplify, and scrutinize specific regions for further study or applications in biotechnology