A protein subunit of human RNase P, Rpp14, and its interacting partner, OIP2, have 3'-->5' exoribonuclease activity

Proc Natl Acad Sci U S A. 2002 Apr 16;99(8):5295-300. doi: 10.1073/pnas.072083699. Epub 2002 Apr 2.

Abstract

The processing of precursor tRNAs at their 5' and 3' termini is a fundamental event in the biosynthesis of tRNA. RNase P is generally responsible for endonucleolytic removal of a leader sequence of precursor tRNA to generate the mature 5' terminus. However, much less is known about the RNase P counterparts or other proteins that are active at the tRNA 3' terminus. Here we show that one of the human RNase P subunits, Rpp14, together with one of its interacting protein partners, OIP2, is a 3'-->5' exoribonuclease with a phosphorolytic activity that processes the 3' terminus of precursor tRNA. Immunoprecipitates of a crude human RNase P complex can process both ends of precursor tRNA by hydrolysis, but purified RNase P has no exonuclease activity. Rpp14 and OIP2 may be part of an exosome activity.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Carrier Proteins / chemistry*
  • Chromatography, Thin Layer
  • DNA / chemistry
  • Endoribonucleases / chemistry*
  • Endoribonucleases / metabolism
  • Escherichia coli / metabolism
  • Escherichia coli Proteins*
  • Exoribonucleases / chemistry
  • Exosome Multienzyme Ribonuclease Complex
  • HeLa Cells
  • Humans
  • Hydrolysis
  • Phosphorylation
  • Precipitin Tests
  • Protein Binding
  • Protein Structure, Tertiary
  • RNA, Catalytic / chemistry*
  • RNA, Catalytic / metabolism
  • RNA, Transfer / chemistry*
  • RNA, Transfer, Tyr / chemistry
  • RNA-Binding Proteins
  • Recombinant Proteins / chemistry
  • Recombinant Proteins / metabolism
  • Ribonuclease P
  • Time Factors

Substances

  • Carrier Proteins
  • Escherichia coli Proteins
  • RNA, Catalytic
  • RNA, Transfer, Tyr
  • RNA-Binding Proteins
  • Recombinant Proteins
  • DNA
  • RNA, Transfer
  • EXOSC8 protein, human
  • Endoribonucleases
  • Exoribonucleases
  • Exosome Multienzyme Ribonuclease Complex
  • RPP14 protein, human
  • Ribonuclease P
  • ribonuclease P, E coli