What is a sticky end?

A sticky end is a term used in molecular biology to describe a specific type of DNA molecule that has a series of unpaired nucleotides (also known as overhangs) at the end of a DNA strand. These overhangs can stick to complementary overhangs on another strand of DNA, enabling the DNA molecules to be joined together more easily.

Sticky ends are generated by the action of certain enzymes called restriction endonucleases, which cleave DNA at specific recognition sites. These enzymes create staggered cuts in the DNA molecule, producing overhanging ends that can base-pair with other overhangs generated by the same enzyme.

Sticky ends play a critical role in recombinant DNA technology since they allow DNA fragments to be joined together in a controlled manner. By using a combination of restriction enzymes with different recognition sites, scientists can generate specific combinations of sticky ends, enabling them to create precise genetic constructs. This technique is widely used in genetic engineering, gene cloning, and biotechnology research.