. 2008 Sep 3;2(1-2):25–45. doi: 10.1007/s12079-008-0026-2

Table 3.

Main ligases used in molecular biology

Enzyme	Requirements	Activity	Main applications/notes
DNA ligases
T4-DNA Ligase	Mg²⁺	Connects blunt and cohesive ends in duplex DNA, RNA or DNA/RNA hybrids	Most frequently used for cloning
T4-DNA Ligase	ATP		Most frequently used for cloning
E. Coli DNA ligase	Mg²⁺	Connects preferentially cohesive double-stranded DNA ends, active on blunt ends DNA in the presence of Ficoll or polyethylene glycol	Ligation when blunt end or RNA/ DNA ligation needs to be avoided
E. Coli DNA ligase	NAD⁺
Thermostable DNA ligases (various sources)		Ligation at high temperature	Not a substitute for T4 or E. Coli ligases, but used for specific techniques like LCR.
RNA ligases
T4 RNA ligase 1	ATP	Ligates single stranded nucleic acids and polynucleotides to RNA molecules	RNA labeling, primer extension
T4 RNA ligase 2 (T4 Rnl-2)	ATP	Ligates double-stranded RNA or connects dsRNA to dsDNA	Repair nicks in dsRNA
Truncated T4 RNL2		Ligates pre-adenylated 5′ end of DNA or RNA to 3′ end of RNA molecules	Optimized linker ligation for cloning of microRNAs