tRNA-intron lyase (EC 4.6.1.16, tRNA intron endonuclease, transfer ribonucleate intron endoribonuclease, tRNA splicing endonuclease, splicing endonuclease, tRNATRPintron endonuclease, transfer splicing endonuclease; systematic name pretRNA lyase (intron-removing; cyclic-2′,3′-phosphate-forming)) is an enzyme. As an endonuclease enzyme, tRNA-intron lyase is responsible for splicing phosphodiester bonds within non-coding ribonucleic acid chains. These non-coding RNA molecules form tRNA molecules after being processed, and this is dependent on tRNA-intron lyase to splice the pretRNA. tRNA processing is an important post-transcriptional modification necessary for tRNA maturation because it locates and removes introns in the pretRNA. This enzyme catalyses the following chemical reaction: