The bone-related Zn finger transcription factor Osterix promotes proliferation of mesenchymal cells
- 28 November 2005
- journal article
- Published by Elsevier BV in Gene
- Vol. 366 (1), 145-151
- https://doi.org/10.1016/j.gene.2005.08.021
Abstract
Osterix is a bone-related transcription factor that functions genetically downstream of Runx2, which controls both growth and differentiation in osteoblasts. Here we assessed the biological function of Osterix in mesenchymal cells that are not normally committed to the osteogenic lineage. Stably transfected NIH3T3 fibroblasts that express exogenous Osterix were examined for their ability to convert into osteoblastic cells by analyzing gene expression profiles of bone phenotype related markers, as well as by measuring bone nodule formation and cell proliferation. Forced expression of Osterix stimulates osteopontin gene expression but not the expression or activity of other bone-related markers, including collagen type I, alkaline phosphatase, osteocalcin, or osteonectin. Moreover, cells stably expressing Osterix do not induce bone nodule formation. Strikingly, both polyclonal and monoclonal cells expressing Osterix exhibit enhanced proliferation. Collectively, these results indicate that Osterix is insufficient to establish osteogenic lineage commitment, perhaps due to the ability of Osterix to promote cell growth. We propose that regulatory pathways operating upstream of or in parallel with Osterix are required for osteogenic conversion of uncommitted mesenchymal cells.Keywords
This publication has 17 references indexed in Scilit:
- The Bone-specific Expression of Runx2 Oscillates during the Cell Cycle to Support a G1-related Antiproliferative Function in OsteoblastsPublished by Elsevier BV ,2005
- BMP-2-induced Osterix expression is mediated by Dlx5 but is independent of Runx2Biochemical and Biophysical Research Communications, 2003
- Phenotype discovery by gene expression profiling: Mapping of biological processes linked to BMP‐2‐mediated osteoblast differentiationJournal of Cellular Biochemistry, 2003
- Cell-Type-Dependent Up-Regulation of In Vitro Mineralization After Overexpression of the Osteoblast-Specific Transcription Factor Runx2/Cbfa1Journal of Bone and Mineral Research, 2002
- The Novel Zinc Finger-Containing Transcription Factor Osterix Is Required for Osteoblast Differentiation and Bone FormationCell, 2002
- Stem cells in tissue engineeringNature, 2001
- Subnuclear targeting of Runx/Cbfa/AML factors is essential for tissue-specific differentiation during embryonic developmentProceedings of the National Academy of Sciences of the United States of America, 2001
- Transient upregulation of CBFA1 in response to bone morphogenetic protein-2 and transforming growth factor ?1 in C2C12 myogenic cells coincides with suppression of the myogenic phenotype but is not sufficient for osteoblast differentiationJournal of Cellular Biochemistry, 1999
- Targeted Disruption of Results in a Complete Lack of Bone Formation owing to Maturational Arrest of OsteoblastsCell, 1997
- Expression patterns of bone-related proteins during osteoblastic differentiation in MC3T3-E1 cellsJournal of Cellular Biochemistry, 1996