QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

Vol. 16, Issue 7, 3401-3410, July 2005

This Article Full Text Full Text (PDF) All Versions of this Article: E05-02-0106v1 16/7/3401    most recent Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Politz, J. C. R. Articles by Pederson, T. Search for Related Content PubMed PubMed Citation Articles by Politz, J. C. R. Articles by Pederson, T.

A Nonribosomal Landscape in the Nucleolus Revealed by the Stem Cell Protein Nucleostemin

Joan C. Ritland Politz ^*, Ilvin Polena ^*, Ian Trask ^* , David P. Bazett-Jones , and Thoru Pederson ^*

^* Department of Biochemistry and Molecular Pharmacology and Program in Cell Dynamics, University of Massachusetts Medical School, Worcester, MA 01605; Program in Cell Biology, Hospital for Sick Children, Toronto, Ontario M5G 1XB, Canada

Submitted February 7, 2005; Revised April 7, 2005; Accepted April 14, 2005
Monitoring Editor: Greg Matera

Nucleostemin is a p53-interactive cell cycle progression factor that shuttles between the nucleolus and nucleoplasm, but it has no known involvement in ribosome synthesis. We found the dynamic properties of nucleostemin differed strikingly from fibrillarin (a protein directly involved in rRNA processing) both in response to rRNA transcription inhibition and in the schedule of reentry into daughter nuclei and the nucleolus during late telophase/early G₁. Furthermore, nucleostemin was excluded from the nucleolar domains in which ribosomes are born—the fibrillar centers and dense fibrillar component. Instead it was concentrated in rRNA-deficient sites within the nucleolar granular component. This finding suggests that the nucleolus may be more subcompartmentalized than previously thought. In support of this concept, electron spectroscopic imaging studies of the nitrogen and phosphorus distribution in the nucleolar granular component revealed regions that are very rich in protein and yet devoid of nucleic acid. Together, these results suggest that the ultrastructural texture of the nucleolar granular component represents not only ribosomal particles but also RNA-free zones populated by proteins or protein complexes that likely serve other functions.

Present address: Department of Biology, Bowdoin College, New Brunswick, ME 04011.

Address correspondence to: Thoru Pederson (thoru.pederson{at}umassmed.edu).

This article has been cited by other articles:

				M.-S. Dai, X.-X. Sun, and H. Lu Aberrant Expression of Nucleostemin Activates p53 and Induces Cell Cycle Arrest via Inhibition of MDM2 Mol. Cell. Biol., July 1, 2008; 28(13): 4365 - 4376. [Abstract] [Full Text] [PDF]

				H. Ma and T. Pederson Nucleophosmin Is a Binding Partner of Nucleostemin in Human Osteosarcoma Cells Mol. Biol. Cell, July 1, 2008; 19(7): 2870 - 2875. [Abstract] [Full Text] [PDF]

				C. H. Eskiw, A. Rapp, D. R. F. Carter, and P. R. Cook RNA polymerase II activity is located on the surface of protein-rich transcription factories J. Cell Sci., June 15, 2008; 121(12): 1999 - 2007. [Abstract] [Full Text] [PDF]

				T. Pederson Ribosomal protein mutations in Diamond-Blackfan anemia: might they operate upstream from protein synthesis? FASEB J, November 1, 2007; 21(13): 3442 - 3445. [Abstract] [Full Text] [PDF]

				W. Condemine, Y. Takahashi, M. Le Bras, and H. de The A nucleolar targeting signal in PML-I addresses PML to nucleolar caps in stressed or senescent cells J. Cell Sci., September 15, 2007; 120(18): 3219 - 3227. [Abstract] [Full Text] [PDF]

				H. Ma and T. Pederson Depletion of the Nucleolar Protein Nucleostemin Causes G1 Cell Cycle Arrest via the p53 Pathway Mol. Biol. Cell, July 1, 2007; 18(7): 2630 - 2635. [Abstract] [Full Text] [PDF]

				L. Meng, H. Yasumoto, and R. Y. L. Tsai Multiple controls regulate nucleostemin partitioning between nucleolus and nucleoplasm J. Cell Sci., December 15, 2006; 119(24): 5124 - 5136. [Abstract] [Full Text] [PDF]

				Q. Zhu, H. Yasumoto, and R. Y. L. Tsai Nucleostemin Delays Cellular Senescence and Negatively Regulates TRF1 Protein Stability Mol. Cell. Biol., December 15, 2006; 26(24): 9279 - 9290. [Abstract] [Full Text] [PDF]

				C. Beekman, M. Nichane, S. De Clercq, M. Maetens, T. Floss, W. Wurst, E. Bellefroid, and J.-C. Marine Evolutionarily Conserved Role of Nucleostemin: Controlling Proliferation of Stem/Progenitor Cells during Early Vertebrate Development Mol. Cell. Biol., December 15, 2006; 26(24): 9291 - 9301. [Abstract] [Full Text] [PDF]

				J. C. Ritland Politz, F. Zhang, and T. Pederson MicroRNA-206 colocalizes with ribosome-rich regions in both the nucleolus and cytoplasm of rat myogenic cells PNAS, December 12, 2006; 103(50): 18957 - 18962. [Abstract] [Full Text] [PDF]

				P. Greda, J. Karasiewicz, and J. A Modlinski Mouse zygotes as recipients in embryo cloning. Reproduction, November 1, 2006; 132(5): 741 - 748. [Abstract] [Full Text] [PDF]

				X. Du, M. R.K. S. Rao, X. Q. Chen, W. Wu, S. Mahalingam, and D. Balasundaram The Homologous Putative GTPases Grn1p from Fission Yeast and the Human GNL3L Are Required for Growth and Play a Role in Processing of Nucleolar Pre-rRNA Mol. Biol. Cell, January 1, 2006; 17(1): 460 - 474. [Abstract] [Full Text] [PDF]