Restriction enzyme

A restriction enzyme or restriction endonuclease is an enzyme that cuts DNA at a particular sequence. There are many known restriction enzymes and each has a particular sequence it recognizes, for example, EcoR1 splices DNA at the palindrome GAATTC reading from 5' to 3', the cut is made between the G and first A. Most known restriction enzymes leave sticky ends after cutting, a property that is very important for their use in gene cloning.