Restriction endonuclease enzyme is used in rDNA techniques for recombinant DNA production. This enzyme cleaves the DNA at specific sequences, allowing for the insertion or deletion of new DNA fragments. DNA ligases are also used to join the ends of the cleaved DNA fragments after the desired genes have been inserted. Vectors such as plasmids and bacteriophages are also used to help in carrying and integrating the desired gene into the host organism's genome.