In molecular biology, ligation refers to the joining of two DNA fragments through the formation of a phosphodiester bond. An enzyme known as a ligase catalyzes the ligation reaction. In the cell, ligases repair single and double strand breaks that occur during DNA replication. In the laboratory, DNA ligase is used during molecular cloning to join DNA fragments of inserts with vectors - carrier DNA molecules that will replicate target fragments in host organisms.
4:47 video Over the past few weeks, the Nobel committees have been announcing the 2015 laureates. This year's winners in the physics and chemistry categories made discoveries about the tiny neutrinos flying through all of us, and the ways our bodies repair DNA.