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Updated: Jul 25, 2026

Purification of Extracellular Trypanosomes, Including African, from Blood by Anion-Exchangers (Diethylaminoethyl-cellulose Columns)
14:26

Purification of Extracellular Trypanosomes, Including African, from Blood by Anion-Exchangers (Diethylaminoethyl-cellulose Columns)

Published on: April 6, 2019

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

S Kelly1, W Singleton, B Wickstead

  • 1Sir William Dunn School of Pathology, University of Oxford, South Parks Road, Oxford OX1 3RE, United Kingdom.

Eukaryotic Cell
|May 10, 2006
PubMed

Insights

Trypanosomes have two Nopp140 proteins: Nopp140 and Nopp140-like protein (TbNoLP). TbNoLP

Area of Science:

  • Molecular biology
  • Cell biology
  • Parasitology

Background:

  • Trypanosomatids, single-celled eukaryotes, possess unique cellular mechanisms.
  • Nopp140 is a key nucleolar protein involved in ribosome biogenesis.
  • The existence of Nopp140 paralogues in trypanosomatids suggests specialized functions.

Purpose of the Study:

  • To investigate the distinct roles and localization of the two Nopp140 homologues in trypanosomatids.
  • To understand the functional implications of the Nopp140-like protein (TbNoLP) in nucleolar organization and ribosome biogenesis.
  • To explore the evolutionary significance of NoLP proteins in nucleoplasmic shuttling.

Main Methods:

  • Immunoprecipitation to identify interacting proteins.
  • Subcellular localization studies using specific antibodies.
  • Gene depletion experiments to assess protein function.
  • Analysis of nucleolar structure and composition.

Main Results:

  • Both canonical Nopp140 and TbNoLP are phosphorylated and associate with RNA polymerase I.
  • Each Nopp140 paralogue exhibits distinct subnuclear localization patterns.
  • Depletion of TbNoLP leads to an enlarged nucleolus with dispersed TbNopp140 regions.
  • NoLP proteins are found in a restricted range of organisms, suggesting convergent evolution.

Conclusions:

  • Trypanosomatids utilize two distinct Nopp140 paralogues with specialized roles in nucleolar function.
  • TbNoLP plays a critical role in maintaining nucleolar structure and organization.
  • The evolutionary pattern of NoLP proteins points towards a conserved function in nucleoplasmic small nucleolar ribonucleoprotein shuttling.

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