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Title: Osterix enhances proliferation and osteogenic potential of bone marrow stromal cells

Abstract

Osterix (Osx) is a zinc-finger-containing transcription factor that is expressed in osteoblasts of all endochondral and membranous bones. In Osx null mice osteoblast differentiation is impaired and bone formation is absent. In this study, we hypothesized that overexpression of Osx in murine bone marrow stromal cells (BMSC) would be able to enhance their osteoblastic differentiation and mineralization in vitro. Retroviral transduction of Osx in BMSC cultured in non-differentiating medium did not affect expression of Runx2/Cbfa1, another key transcription factor of osteoblast differentiation, but induced an increase in the expression of other markers associated with the osteoblastic lineage including alkaline phosphatase, bone sialoprotein, osteocalcin, and osteopontin. Retroviral transduction of Osx in BMSC also increased their proliferation, alkaline phosphatase activity, and ability to form bone nodules. These events occurred without significant changes in the expression of {alpha}1(II) procollagen or lipoprotein lipase, which are markers of chondrogenic and adipogenic differentiation, respectively.

Authors:
 [1];  [2];  [1]
  1. Division of Oral Biology, Tufts University School of Dental Medicine, Boston, MA 02111 (United States)
  2. Division of Oral Biology, Tufts University School of Dental Medicine, Boston, MA 02111 (United States). E-mail: paloma.valverde@tufts.edu
Publication Date:
OSTI Identifier:
20798859
Resource Type:
Journal Article
Resource Relation:
Journal Name: Biochemical and Biophysical Research Communications; Journal Volume: 341; Journal Issue: 4; Other Information: DOI: 10.1016/j.bbrc.2006.01.092; PII: S0006-291X(06)00150-1; Copyright (c) 2006 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
60 APPLIED LIFE SCIENCES; ALKALINE PHOSPHATASE; BONE MARROW; CELL PROLIFERATION; CONNECTIVE TISSUE CELLS; IN VITRO; LIPASES; LIPOPROTEINS; MICE; MINERALIZATION; SKELETON; TRANSCRIPTION FACTORS

Citation Formats

Tu Qisheng, Valverde, Paloma, and Chen, Jake. Osterix enhances proliferation and osteogenic potential of bone marrow stromal cells. United States: N. p., 2006. Web.
Tu Qisheng, Valverde, Paloma, & Chen, Jake. Osterix enhances proliferation and osteogenic potential of bone marrow stromal cells. United States.
Tu Qisheng, Valverde, Paloma, and Chen, Jake. Fri . "Osterix enhances proliferation and osteogenic potential of bone marrow stromal cells". United States. doi:.
@article{osti_20798859,
title = {Osterix enhances proliferation and osteogenic potential of bone marrow stromal cells},
author = {Tu Qisheng and Valverde, Paloma and Chen, Jake},
abstractNote = {Osterix (Osx) is a zinc-finger-containing transcription factor that is expressed in osteoblasts of all endochondral and membranous bones. In Osx null mice osteoblast differentiation is impaired and bone formation is absent. In this study, we hypothesized that overexpression of Osx in murine bone marrow stromal cells (BMSC) would be able to enhance their osteoblastic differentiation and mineralization in vitro. Retroviral transduction of Osx in BMSC cultured in non-differentiating medium did not affect expression of Runx2/Cbfa1, another key transcription factor of osteoblast differentiation, but induced an increase in the expression of other markers associated with the osteoblastic lineage including alkaline phosphatase, bone sialoprotein, osteocalcin, and osteopontin. Retroviral transduction of Osx in BMSC also increased their proliferation, alkaline phosphatase activity, and ability to form bone nodules. These events occurred without significant changes in the expression of {alpha}1(II) procollagen or lipoprotein lipase, which are markers of chondrogenic and adipogenic differentiation, respectively.},
doi = {},
journal = {Biochemical and Biophysical Research Communications},
number = 4,
volume = 341,
place = {United States},
year = {Fri Mar 24 00:00:00 EST 2006},
month = {Fri Mar 24 00:00:00 EST 2006}
}
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