Histochemistry and Cell Biology

, Volume 125, Issue 1, pp 127–137

Nucleolus: from structure to dynamics

Reviews

DOI: 10.1007/s00418-005-0046-4

Cite this article as:
Hernandez-Verdun, D. Histochem Cell Biol (2006) 125: 127. doi:10.1007/s00418-005-0046-4

Abstract

The nucleolus, a large nuclear domain, is the ribosome factory of the cells. Ribosomal RNAs are synthesized, processed and assembled with ribosomal proteins in the nucleolus, and the ribosome subunits are then transported to the cytoplasm. In this review, the structural organization of the nucleolus and the dynamics of the nucleolar proteins are discussed in an attempt to link both information. By electron microscopy, three main nucleolar components corresponding to different steps of ribosome biogenesis are identified and the nucleolar organization reflects its activity. Time-lapse videomicroscopy and fluorescent recovery after photobleaching (FRAP) demonstrate that mobility of GFP-tagged nucleolar proteins is slower in the nucleolus than in the nucleoplasm. Fluorescent recovery rates change with inhibition of transcription, decreased temperature and depletion of ATP, indicating that recovery is correlated with cell activity. At the exit of mitosis, the nucleolar processing machinery is first concentrated in prenucleolar bodies (PNBs). The dynamics of the PNBs suggests a steady state favoring residence of processing factors that are then released in a control- and time-dependent manner. Time-lapse analysis of fluorescence resonance energy transfer demonstrates that processing complexes are formed in PNBs. Finally, the nucleolus appears at the center of several trafficking pathways in the nucleus.

Keywords

Nucleolus Organization Dynamics Assembly 

Supplementary material

418_2005_46_MOESM1_ESM.mov (351 kb)
Supplementary material

Copyright information

© Springer-Verlag 2005

Authors and Affiliations

  1. 1.Nuclei and Cell Cycle, Institut Jacques Monod, CNRSUniversité Paris VI et Paris VIIParis, Cedex 05France