tRNA intron endonuclease catalytic (IPR006677) is a homotetrameric tRNA-intron endonuclease that contains a three-layered α/β/α domain at the C-terminus. Additionally, it contains domains 2 and 4 (C-terminus) in a homodimeric enzyme. A tRNA-intron endonuclease cuts the pre-tRNA at the 5' and 3' splice sites to free the intron. This gets rid of the tRNA intron. The product consists of an intron, two tRNA halves with 2', 3' cyclic phosphates, and 5'-hydroxyl termini.