UMMS Affiliation

Program in Cell Dynamics; Department of Biochemistry and Molecular Pharmacology; Department of Molecular Genetics and Microbiology

Publication Date


Document Type



ADP-Ribosylation Factors; Carrier Proteins; Cell Nucleolus; Down-Regulation; *G1 Phase; Hela Cells; Humans; Nuclear Proteins; Proto-Oncogene Proteins c-mdm2; Retinoblastoma Protein; Tumor Suppressor Protein p53; Up-Regulation


Life Sciences | Medicine and Health Sciences


Nucleostemin (NS) is a nucleolar protein expressed in adult and embryo-derived stem cells, transformed cell lines, and tumors. NS decreases when proliferating cells exit the cell cycle, but it is unknown how NS is controlled, and how it participates in cell growth regulation. Here, we show that NS is down-regulated by the tumor suppressor p14(ARF) and that NS knockdown elevates the level of tumor suppressor p53. NS knockdown led to G1 cell cycle arrest in p53-positive cells but not in cells in which p53 was genetically deficient or depleted by small interfering RNA knockdown. These results demonstrate that, in the cells investigated, the level of NS is regulated by p14(ARF) and the control of the G1/S transition by NS operates in a p53-dependent manner.

DOI of Published Version



Mol Biol Cell. 2007 Jul;18(7):2630-5. Epub 2007 May 9. Link to article on publisher's site

Journal/Book/Conference Title

Molecular biology of the cell

Related Resources

Link to Article in PubMed

PubMed ID




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