PUMILIO-2 Is Involved in the Positive Regulation of Cellular Proliferation in Human Adipose-Derived Stem Cells
- 20 January 2012
- journal article
- research article
- Published by Mary Ann Liebert Inc in Stem Cells and Development
- Vol. 21 (2), 217-227
- https://doi.org/10.1089/scd.2011.0143
Abstract
Stem cells can either differentiate into more specialized cells or undergo self-renewal. Several lines of evidence from different organisms suggest that these processes depend on the post-transcriptional regulation of gene expression. The presence of the PUF [Pumilio/FBF (fem-3 binding factor)] domain defines a conserved family of RNA binding proteins involved in repressing gene expression. It has been suggested that a conserved function of PUF proteins is to repress differentiation and sustain the mitotic proliferation of stem cells. In humans, Pumilio-2 (PUM2) is expressed in embryonic stem cells and adult germ cells. Here we show that PUM2 is expressed in a subpopulation of adipose-derived stem cell (ASC) cultures, with a granular pattern of staining in the cytoplasm. Protein levels of PUM2 showed no changes during the differentiation of ASCs into adipocytes. Moreover, RNAi knockdown of pum2 did not alter the rate of adipogenic differentiation compared with wild-type control cells. A ribonomic approach was used to identify PUM2-associated mRNAs. Microarray analysis showed that PUM2-bound mRNAs are part of gene networks involved in cell proliferation and gene expression control. We studied pum2 expression in cell cultures with low or very high levels of proliferation and found that changes in pum2 production were dependent on the proliferation status of the cell. Transient knockdown of pum2 expression by RNAi impaired proliferation of ASCs in vitro. Our results suggest that PUM2 does not repress differentiation of ASCs but rather is involved in the positive control of ASCs division and proliferation.Keywords
This publication has 37 references indexed in Scilit:
- Biochemical Characterization of Pumilio1 and Pumilio2 in Xenopus OocytesPublished by Elsevier BV ,2011
- Transcriptome-wide Identification of RNA-Binding Protein and MicroRNA Target Sites by PAR-CLIPCell, 2010
- Genome-wide analysis of mRNA targets for Caenorhabditis elegans FBF, a conserved stem cell regulatorProceedings of the National Academy of Sciences of the United States of America, 2010
- C. elegans RNA-binding proteins PUF-8 and MEX-3 function redundantly to promote germline stem cell mitosisDevelopmental Biology, 2009
- Proliferative control in Drosophila stem cellsCurrent Opinion in Cell Biology, 2008
- Comparative Analysis of mRNA Targets for Human PUF-Family Proteins Suggests Extensive Interaction with the miRNA Regulatory SystemPLOS ONE, 2008
- Ribonomic Analysis of Human Pum1 Reveals cis-trans Conservation across Species despite Evolution of Diverse mRNA Target SetsMolecular and Cellular Biology, 2008
- Molecular basis of pluripotencyHuman Molecular Genetics, 2008
- Analysis of Turnover and Translation Regulatory RNA-Binding Protein Expression through Binding to Cognate mRNAsMolecular and Cellular Biology, 2007
- A conserved RNA-binding protein controls germline stem cells in Caenorhabditis elegansNature, 2002