How are restriction and DNA ligase enzymes used to insert a foreign gene into a plasmid?

2 Answers
Feb 28, 2017
  • both of them are used in recombinant DNA technology .


  • In the process , a DNA segment of human is taken and is cut with restrictions enzyme from particular site.
  • another DNA is taken which acts as vector.
  • foreign DNA is inserted in vector DNA .
  • It is joined with DNA ligase .
  • this recombinant dna is introduced into Ecoli ,the foreign gene introduced will show same working as in human.web image
Mar 1, 2017

Restriction enzyme is able to cut a DNA double helix in a certain way, only at palindromic sequences. Ligase enzyme is able to join together such cut ends of nucleic acids.


Plasmid is used as vector in which the foreign gene is inserted.

Both ends of alien gene are cut using a particular restriction endonuclease. The same enzyme should be used to cut open the circular plasmid.

The alien gene could then be inserted in the plasmid catalysed by action of ligase.

Restriction enzyme is called molecular scissor while ligase enzyme works like a glue.