Characterization and differential nuclear localization of Nopp140 and a novel Nopp140-like protein in trypanosomes

Eukaryot Cell. 2006 May;5(5):876-9. doi: 10.1128/EC.5.5.876-879.2006.

Abstract

Trypanosomatids possess two homologues of Nopp140: a canonical Nopp140 and a Nopp140-like protein (TbNoLP) in which a GAR domain replaces the C-terminal SRP40 domain. Both are phosphorylated and coimmunoprecipitate with RNA polymerase I. Each paralogue has a distinct subnuclear localization, and depletion of TbNoLP produces an enlarged nucleolus in which TbNopp140-containing regions disperse. The restricted occurrence pattern of NoLP proteins reflects an intriguing convergence in evolution, suggestive of a function in nucleoplasmic small nucleolar ribonucleoprotein shuttling.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Cell Nucleolus / chemistry
  • Cell Nucleus / chemistry*
  • Molecular Sequence Data
  • Nuclear Proteins / analysis
  • Nuclear Proteins / chemistry*
  • Nuclear Proteins / genetics
  • Nuclear Proteins / physiology
  • Phosphoproteins / analysis
  • Phosphoproteins / chemistry*
  • Phosphoproteins / genetics
  • Phosphoproteins / physiology
  • Phosphorylation
  • Protozoan Proteins / analysis
  • Protozoan Proteins / chemistry*
  • Protozoan Proteins / genetics
  • Protozoan Proteins / physiology
  • RNA Interference
  • RNA Polymerase I / metabolism
  • Ribonucleoproteins, Small Nucleolar / metabolism
  • Trypanosoma brucei brucei / chemistry*
  • Trypanosoma brucei brucei / cytology
  • Trypanosoma brucei brucei / metabolism

Substances

  • NOLC1 protein, human
  • Nuclear Proteins
  • Phosphoproteins
  • Protozoan Proteins
  • Ribonucleoproteins, Small Nucleolar
  • RNA Polymerase I