Question

Which of the following is correct in the process of insertional inactivation?

• A. A recombinant DNA is inserted within the recognition site for EcoRI
• B. A recombinant DNA is inserted within the coding sequence of proteins involved in the replication of the plasmid
• C. The coding sequence of enzyme β-galactosidase is inserted in the recombinant DNA
• D. A recombinant DNA is inserted within the coding sequence of enzyme β-galactosidase

Answer 1

The correct option is D A recombinant DNA is inserted within the coding sequence of enzyme β-galactosidase

Insertional inactivation is the property used for screening of recombinant colonies.

In recombinant DNA technology, a gene of interest is inserted into a plasmid which is taken up by competant cells.

In this case, as the cloning site is in the middle of the beta-galactosidase gene. The gene of interest is inserted within the cloning site inside the beta-galactosidase gene. The gene thus gets disrupted. So, it is inactivated due to the insertion of the gene of interest. This is called insertional inactivation.