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Title: Transforming growth factor-{beta}1 regulates fibronectin isoform expression and splicing factor SRp40 expression during ATDC5 chondrogenic maturation

Abstract

Fibronectin (FN) isoform expression is altered during chondrocyte commitment and maturation, with cartilage favoring expression of FN isoforms that includes the type II repeat extra domain B (EDB) but excludes extra domain A (EDA). We and others have hypothesized that the regulated splicing of FN mRNAs is necessary for the progression of chondrogenesis. To test this, we treated the pre-chondrogenic cell line ATDC5 with transforming growth factor-{beta}1, which has been shown to modulate expression of the EDA and EDB exons, as well as the late markers of chondrocyte maturation; it also slightly accelerates the early acquisition of a sulfated proteoglycan matrix without affecting cell proliferation. When chondrocytes are treated with TGF-{beta}1, the EDA exon is preferentially excluded at all times whereas the EDB exon is relatively depleted at early times. This regulated alternative splicing of FN correlates with the regulation of alternative splicing of SRp40, a splicing factor facilitating inclusion of the EDA exon. To determine if overexpression of the SRp40 isoforms altered FN and FN EDA organization, cDNAs encoding these isoforms were overexpressed in ATDC5 cells. Overexpression of the long-form of SRp40 yielded an FN organization similar to TGF-{beta}1 treatment; whereas overexpression of the short form of SRp40 (whichmore » facilitates EDA inclusion) increased formation of long-thick FN fibrils. Therefore, we conclude that the effects of TGF-{beta}1 on FN splicing during chondrogenesis may be largely dependent on its effect on SRp40 isoform expression.« less

Authors:
 [1];  [1];  [1];  [1];  [1];  [1];  [2];  [3];  [3];  [4];  [5];  [3];  [4];  [6]
  1. Department of Orthopaedic Surgery, Thomas Jefferson University, Philadelphia, PA 19107 (United States)
  2. Division of Rheumatology, Department of Medicine, Thomas Jefferson University, Philadelphia, PA 19107 (United States)
  3. Department of Biochemistry and Molecular Pharmacology, Thomas Jefferson University, Philadelphia, PA 19107 (United States)
  4. (United States)
  5. Cartilage Biology and Orthopaedics Branch, NIAMS, NIH, Bethesda, MD 20892-8022 (United States)
  6. Department of Orthopaedic Surgery, Thomas Jefferson University, Philadelphia, PA 19107 (United States) and Department of Biochemistry and Molecular Pharmacology, Thomas Jefferson University, Philadelphia, PA 19107 (United States). E-mail: Noreen.Hickok@jefferson.edu
Publication Date:
OSTI Identifier:
20972143
Resource Type:
Journal Article
Resource Relation:
Journal Name: Experimental Cell Research; Journal Volume: 313; Journal Issue: 8; Other Information: DOI: 10.1016/j.yexcr.2007.01.028; PII: S0014-4827(07)00043-2; Copyright (c) 2007 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; CARTILAGE; CELL PROLIFERATION; COLLAGEN; EXONS; GROWTH FACTORS; MATURATION; SPLICING

Citation Formats

Han Fei, Gilbert, James R., Harrison, Gerald, Adams, Christopher S., Freeman, Theresa, Tao Zhuliang, Zaka, Raihana, Liang Hongyan, Williams, Charlene, Division of Rheumatology, Department of Medicine, Thomas Jefferson University, Philadelphia, PA 19107, Tuan, Rocky S., Norton, Pamela A., Jefferson Center for Biomedical Research, Thomas Jefferson University, Philadelphia, PA 19107, and Hickok, Noreen J. Transforming growth factor-{beta}1 regulates fibronectin isoform expression and splicing factor SRp40 expression during ATDC5 chondrogenic maturation. United States: N. p., 2007. Web. doi:10.1016/j.yexcr.2007.01.028.
Han Fei, Gilbert, James R., Harrison, Gerald, Adams, Christopher S., Freeman, Theresa, Tao Zhuliang, Zaka, Raihana, Liang Hongyan, Williams, Charlene, Division of Rheumatology, Department of Medicine, Thomas Jefferson University, Philadelphia, PA 19107, Tuan, Rocky S., Norton, Pamela A., Jefferson Center for Biomedical Research, Thomas Jefferson University, Philadelphia, PA 19107, & Hickok, Noreen J. Transforming growth factor-{beta}1 regulates fibronectin isoform expression and splicing factor SRp40 expression during ATDC5 chondrogenic maturation. United States. doi:10.1016/j.yexcr.2007.01.028.
Han Fei, Gilbert, James R., Harrison, Gerald, Adams, Christopher S., Freeman, Theresa, Tao Zhuliang, Zaka, Raihana, Liang Hongyan, Williams, Charlene, Division of Rheumatology, Department of Medicine, Thomas Jefferson University, Philadelphia, PA 19107, Tuan, Rocky S., Norton, Pamela A., Jefferson Center for Biomedical Research, Thomas Jefferson University, Philadelphia, PA 19107, and Hickok, Noreen J. Tue . "Transforming growth factor-{beta}1 regulates fibronectin isoform expression and splicing factor SRp40 expression during ATDC5 chondrogenic maturation". United States. doi:10.1016/j.yexcr.2007.01.028.
@article{osti_20972143,
title = {Transforming growth factor-{beta}1 regulates fibronectin isoform expression and splicing factor SRp40 expression during ATDC5 chondrogenic maturation},
author = {Han Fei and Gilbert, James R. and Harrison, Gerald and Adams, Christopher S. and Freeman, Theresa and Tao Zhuliang and Zaka, Raihana and Liang Hongyan and Williams, Charlene and Division of Rheumatology, Department of Medicine, Thomas Jefferson University, Philadelphia, PA 19107 and Tuan, Rocky S. and Norton, Pamela A. and Jefferson Center for Biomedical Research, Thomas Jefferson University, Philadelphia, PA 19107 and Hickok, Noreen J.},
abstractNote = {Fibronectin (FN) isoform expression is altered during chondrocyte commitment and maturation, with cartilage favoring expression of FN isoforms that includes the type II repeat extra domain B (EDB) but excludes extra domain A (EDA). We and others have hypothesized that the regulated splicing of FN mRNAs is necessary for the progression of chondrogenesis. To test this, we treated the pre-chondrogenic cell line ATDC5 with transforming growth factor-{beta}1, which has been shown to modulate expression of the EDA and EDB exons, as well as the late markers of chondrocyte maturation; it also slightly accelerates the early acquisition of a sulfated proteoglycan matrix without affecting cell proliferation. When chondrocytes are treated with TGF-{beta}1, the EDA exon is preferentially excluded at all times whereas the EDB exon is relatively depleted at early times. This regulated alternative splicing of FN correlates with the regulation of alternative splicing of SRp40, a splicing factor facilitating inclusion of the EDA exon. To determine if overexpression of the SRp40 isoforms altered FN and FN EDA organization, cDNAs encoding these isoforms were overexpressed in ATDC5 cells. Overexpression of the long-form of SRp40 yielded an FN organization similar to TGF-{beta}1 treatment; whereas overexpression of the short form of SRp40 (which facilitates EDA inclusion) increased formation of long-thick FN fibrils. Therefore, we conclude that the effects of TGF-{beta}1 on FN splicing during chondrogenesis may be largely dependent on its effect on SRp40 isoform expression.},
doi = {10.1016/j.yexcr.2007.01.028},
journal = {Experimental Cell Research},
number = 8,
volume = 313,
place = {United States},
year = {Tue May 01 00:00:00 EDT 2007},
month = {Tue May 01 00:00:00 EDT 2007}
}
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