5.12: Understand How Restriction Enzymes are used to Cut DNA at Specific Sites and Ligase Enzymes are used to Join Pieces of DNA Together

RESTRICTION ENZYME: An enzyme that cleaves DNA at specific site to obtain desired gene and leaves sticky ends

RESTRICTION ENZYME

Diagram showing the role of Restriction Enzymes

EXPLANATION: In order to incorporate gene of interest into vector (vehicle that is used to deliver genetic material to target cell), same restriction enzyme must be used at specific sites As restriction enzymes cleave the double stranded DNA to create sticky ends, these complementary overhangs ensures the gene of interest is inserted in the correct orientation in vector The same restriction enzyme is used to cut out gene of interest from DNA, and to cut open Plasmid vector to leave sticky ends on both As a result, these sticky ends of the gene and vector overlap via complementary base pairing to be joined together by Ligase enzyme, ensuring gene is inserted in the correct orientation

LIGASE ENZYME: An enzyme that forms bonds between Vector and Gene to join them together

LIGASE ENZYME

Diagram showing the role of Ligase Enzymes

EXPLANATION: With sticky ends of the gene and vector overlapping via complementary base pairing, they are spliced together by the enzyme DNA ligase to form a recombinant Plasmid DNA Ligase forms bonds between Vector and Gene to join them together, allowing recombinant Plasmid to be introduced into an appropriate host or organism to express the desired trait encoded by the gene of interest