Article (Scientific journals)
Structural and functional organization of ribosomal genes within the mammalian cell nucleolus.
Derenzini, Massimo; Pasquinelli, Gianandrea; O'Donohue, Marie*-Francoise et al.
2006In Journal of Histochemistry and Cytochemistry, 54 (2), p. 131-45
Peer Reviewed verified by ORBi
 

Files


Full Text
JHC 2006 Derenzini et al.pdf
Publisher postprint (6.27 MB)
Request a copy

All documents in ORBi are protected by a user license.

Send to



Details



Keywords :
Animals; Cell Nucleolus/genetics/metabolism/ultrastructure; Chromatin/genetics/ultrastructure; DNA, Ribosomal/chemistry; Humans; Mammals; Microscopy, Electron; Nucleic Acid Conformation; RNA Precursors/biosynthesis; RNA, Ribosomal/biosynthesis/genetics; Ribosomes/genetics; Transcription, Genetic
Abstract :
[en] Data on the in situ structural-functional organization of ribosomal genes in the mammalian cell nucleolus are reviewed here. Major findings on chromatin structure in situ come from investigations carried out using the Feulgen-like osmium ammine reaction as a highly specific electron-opaque DNA tracer. Intranucleolar chromatin shows three different levels of organization: compact clumps, fibers ranging from 11 to 30 nm, and loose agglomerates of extended DNA filaments. Both clumps and fibers of chromatin exhibit a nucleosomal organization that is lacking in the loose agglomerates of extended DNA filaments. In fact, these filaments constantly show a thickness of 2-3 nm, the same as a DNA double-helix molecule. The loose agglomerates of DNA filaments are located in the fibrillar centers, the interphase counterpart of metaphase NORs, therefore being constituted by ribosomal DNA. The extended, non-nucleosomal configuration of this rDNA has been shown to be independent of transcriptional activity and characterizes ribosome genes that are either transcribed or transcriptionally silent. Data reviewed are consistent with a model of control for ribosome gene activity that is not mediated by changes in chromatin structure. The presence of rDNA in mammalian cells always structurally ready for transcription might facilitate a more rapid adjustment of the ribosome production in response to the metabolic needs of the cell.
Disciplines :
Anatomy (cytology, histology, embryology...) & physiology
Author, co-author :
Derenzini, Massimo
Pasquinelli, Gianandrea
O'Donohue, Marie*-Francoise
Ploton, Dominique
Thiry, Marc  ;  Université de Liège - ULiège > Département des sciences de la vie > Biologie cellulaire
Language :
English
Title :
Structural and functional organization of ribosomal genes within the mammalian cell nucleolus.
Publication date :
2006
Journal title :
Journal of Histochemistry and Cytochemistry
ISSN :
0022-1554
eISSN :
1551-5044
Publisher :
Histochemical Society, New York, United States - New York
Volume :
54
Issue :
2
Pages :
131-45
Peer reviewed :
Peer Reviewed verified by ORBi
Available on ORBi :
since 28 November 2009

Statistics


Number of views
48 (2 by ULiège)
Number of downloads
0 (0 by ULiège)

Scopus citations®
 
67
Scopus citations®
without self-citations
50
OpenCitations
 
56

Bibliography


Similar publications



Contact ORBi