Zinc phosphodiesterase, which displays tRNA 3'-processing endonuclease activity (PubMed:12032089, PubMed:16118225, PubMed:18052196, PubMed:19411372). Involved in tRNA maturation, by removing a 3'-trailer from precursor tRNA (PubMed:12032089, PubMed:18052196, PubMed:19411372). Can use bis-(p-nitophenyl) phosphate (bpNPP) as substrate (PubMed:18052196). Involved in the processing of small nucleolar RNAs (snoRNAs) (PubMed:19420328). Endonucleolytic cleavage of RNA, removing extra 3' nucleotides from tRNA precursor, generating 3' termini of tRNAs. A 3'-hydroxy group is left at the tRNA terminus and a 5'-phosphoryl group is left at the trailer molecule. Besides the tightly bound Zn(2+) ion, TRZ1 requires additional Ca(2+), Mn(2+) or Mg(2+) for pre-tRNA processing, while bpNPP hydrolysis occurs without addition of metal ions but is stimulated 2- to 3-fold when free Mn(2+) or Zn(2+) ions are added. kcat is 7.4 sec(-1) with bpNPP as substrate. Homodimer. The C-terminus (270-280) is essential for tRNA binding and processing activity. No visible phenotype when grown under standard conditions. Belongs to the RNase Z family.