The traffic of proteins between nucleolar organizer regions and prenucleolar bodies governs the assembly of the nucleolus at exit of mitosis.

ABSTRACT: The building of nuclear bodies after mitosis is a coordinated event crucial for nuclear organization and function. The nucleolus is assembled during early G(1) phase. Here, two periods (early G1a and early G1b) have been defined. During these periods, the nucleolar compartments (DFC, GC) corresponding to different steps of ribosome biogenesis are progressively assembled. In telophase, rDNA transcription is first activated and PNBs (reservoirs of nucleolar processing proteins) are formed. The traffic of the processing proteins between incipient nucleoli and PNBs was analyzed using photoactivation. We demonstrate that the DFC protein fibrillarin passes from one incipient nucleolus to other nucleoli but not to PNBs, and that the GC proteins, B23/NPM and Nop52, shuttle between PNBs and incipie

SUBMITTER: Muro E 

PROVIDER: S-EPMC3030696 | biostudies-literature | 2010 Mar-Apr

REPOSITORIES: biostudies-literature