T4 RNA Ligase 1

T4 RNA Ligase 1 is an ATP-dependent ligase derived from bacteriophage T4. It catalyzes the ligation of a 5' phosphoryl-terminated nucleic acid donor to a 3 hydroxyl-terminated nucleic acid acceptor through the formation of a 3'→5' phosphodiester bond with hydrolysis of ATP to AMP and PPi. The ligation efficiency of T4 RNA Ligase 1 varies significantly for different substrates, following the order: ssRNA-ssRNA>ssRNA-ssDNA>ssDNA-ssDNA. Additionally, T4 RNA Ligase 1 can also be used for ligation between RNA and mononucleotides, provided that the mononucleotides are phosphorylated at both the 5' and 3' ends. This application is commonly used for 3'-end labeling of RNA.