DNA Cloning with Plasmids

This animation describes a genetic engineering technique called DNA cloning, which can be used to make bacteria express a foreign gene, typically from another species.

During DNA cloning, a new gene is inserted into a loop of bacterial DNA called a plasmid. As shown in the animation, the plasmid is first cut with a restriction enzyme so that the gene of interest, which is isolated from another organism, can be inserted into the loop. The loose ends of the DNA are then stitched together by an enzyme called DNA ligase. Bacteria that have incorporated the resulting plasmid will manufacture the protein encoded by the target gene.

Depending on students’ background, it may be helpful to pause the animation at various points to discuss different structures or steps in the method.