InterPro domain: IPR038837

tRNA ligase 1 (RNL) is involved in the pre-tRNA splicing process in plants. Pre-tRNA splicing requires intron removal by an endonuclease, and a ligase for joining the resulting tRNA halves. In Arabidopsis, the endonuclease is encoded by two genes, SEN1 and SEN2 [ 1 ], and tRNA ligase is encoded by one gene, AtRNL [ 2 ]. Like fungal tRNA ligases, a plant tRNA ligase is a multifunctional enzyme consisting of three domains each with a different activity in the order: ligase, kinase and cyclic phosphodiesterase (CPDase). The polynucleotide kinase domain heals the broken ends to generate the 3'-OH, 2'-PO4, and 5'-PO4 required for sealing by the ligase domain [ 3 ].

1. Identification of two catalytic subunits of tRNA splicing endonuclease from Arabidopsis thaliana. Gene 257, 177-85
2. Plant tRNA ligases are multifunctional enzymes that have diverged in sequence and substrate specificity from RNA ligases of other phylogenetic origins. Nucleic Acids Res. 33, 388-99
3. Distinctive kinetics and substrate specificities of plant and fungal tRNA ligases. RNA 20, 462-73