Knocking-down the expression of nucleostemin significantly decreases rate of proliferation of rat bone marrow stromal stem cells in an apparently p53-independent manner.
Cell Prolif
; 41(1): 28-35, 2008 Feb.
Article
em En
| MEDLINE
| ID: mdl-18211284
ABSTRACT
OBJECTIVES:
Nucleostemin (NS) is a recently identified GTP-binding protein, predominantly expressed in embryonic and adult stem cells but not in terminally differentiated cells. NS is expressed in bone marrow-derived mesenchymal stem cells, and its expression ceases upon induction of neural differentiation. The major aim of this study was to determine whether down-regulation of NS expression acts as a promoter, or otherwise as a by-product of differentiation and senescence processes. MATERIALS ANDMETHODS:
We used RNA interference protocols to specifically knock down NS in rat bone marrow-derived stromal stem cells. Changes in rate of proliferation and cell cycle profile after knocking-down of NS were measured. In addition, changes in expression of associated genes were studied by semiquantitative RT-PCR, Western blotting and immunocytochemistery.RESULTS:
Knocked-down expression of NS caused a significant decrease in the rate of cell proliferation with concomitant shutting off of expression of cyclin D1 and survivin, two other well-known regulators of cell proliferation. Interestingly, we noticed no obvious changes in expression level of p21, the main effector of p53 for its cell cycle repressing function.CONCLUSION:
Our findings revealed a master role for NS in promoting proliferation of rat bone marrow-derived stromal stem cells. Moreover, we suggest that despite previous proposals, the cell cycle arrest/inhibitory role of NS is unlikely to be related to its proposed property of interaction with p53.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Células da Medula Óssea
/
Proteínas Nucleares
/
Proteínas de Transporte
/
Proteína Supressora de Tumor p53
/
Células Estromais
/
Proliferação de Células
Tipo de estudo:
Prognostic_studies
Limite:
Animals
Idioma:
En
Revista:
Cell Prolif
Ano de publicação:
2008
Tipo de documento:
Article
País de afiliação:
Irã