Regulation of the human tRNase Z S gene expression

There are two types of tRNA 3′ processing endoribonucleases (tRNase Z): a short form (tRNase Z S ) and a long form (tRNase Z L ). Although the human genome contains both genes, little is known about the physiological role of tRNase Z S . We found that the human tRNase Z S gene expression appears to be post‐transcriptionally regulated. Additionally, analyses for cis ‐regulatory elements for the tRNase Z S gene transcription suggested that transcription factors that bind to five different sites on the promoter work together to potentiate the transcription initiation. Furthermore, we found that tRNase Z S is predominantly present in the cytosol and hardly in the nucleus.