NEETZoologyBiotechnology - Principles and Processes
When a restriction endonuclease cuts both the vector and the foreign DNA a little away from the centre of their respective palindromic sites, it generates single-stranded overhanging stretches at the ends. What specific advantage does this cutting pattern provide during the construction of a recombinant DNA molecule?
Options
- AIt prevents the action of exonucleases from degrading the newly exposed DNA ends.
- BIt provides a free 3'-OH group that allows DNA polymerase to easily synthesize a new complementary strand.
- CIt ensures that the recombinant DNA molecule can easily undergo transformation into the competent host cell.
- DIt produces sticky ends that form hydrogen bonds with their complementary cut counterparts, facilitating the a
Correct answer
D. It produces sticky ends that form hydrogen bonds with their complementary cut counterparts, facilitating the a
Step-by-step solution
Restriction endonucleases that cut the DNA strand a little away from the centre of the palindromic sites generate single-stranded overhanging stretches called sticky ends. These ends are called sticky because they readily form hydrogen bonds with their complementary cut counterparts. This stickiness of the ends specifically facilitates the action of the enzyme DNA ligase, which joins the foreign DNA and vector DNA molecules together to form a stable recombinant DNA. The sticky ends do not prevent exonuclease action