A novel role for Bcl-2 associated-athanogene-1 (Bag-1) in regulation of the endoplasmic reticulum stress response in mammalian chondrocytes.

Title

A novel role for Bcl-2 associated-athanogene-1 (Bag-1) in regulation of the endoplasmic reticulum stress response in mammalian chondrocytes.

Creator

Yang Ling; McBurney Denise; Tang Shou-Ching; Carlson Sara G; Horton Walter E Jr

Publisher

Journal of cellular biochemistry

Date

2007
2007-10

Description

BAG-1 (Bcl-2 associated athanogene-1) is a multifunctional protein, linking cell proliferation, cell death, protein folding, and cell stress. In vivo, BAG-1 is expressed in growth plate and articular cartilage, and the expression of BAG-1 is decreased with aging. Chondrocytes respond to endoplasmic reticulum (ER) stress with decreased expression of extracellular matrix proteins, and prolonged ER stress leads to chondrocyte apoptosis. Here we demonstrate for the first time that BAG-1 is involved in ER stress-induced apoptosis in chondrocytes. Induction of ER stress through multiple mechanisms all resulted in downregulation of BAG-1 expression. In addition, direct suppression of BAG-1 expression resulted in chondrocyte growth arrest and apoptosis, while stable overexpression of BAG-1 delayed the onset of ER stress-mediated apoptosis. In addition to regulating apoptosis, we also observed decreased expression of collagen type II in BAG-1 deficient chondrocytes. In contrast, overexpression of BAG-1 resulted in increased expression of collagen type II. Moreover, under ER stress conditions, the reduced expression of collagen type II was delayed in chondrocytes overexpressing BAG-1. These results suggest a novel role for BAG-1 in supporting viability and matrix expression of chondrocytes.

Subject

*Gene Expression Regulation; Animals; Apoptosis; Biological; Cell Proliferation; Chondrocytes/*metabolism/pathology; Collagen Type II/metabolism; DNA-Binding Proteins/*metabolism/physiology; Endoplasmic Reticulum/metabolism; Models; Phenotype; Rats; RNA Interference; Subcellular Fractions/metabolism; Time Factors; Transcription Factors/*metabolism/physiology; Transfection

Identifier

Rights

Article information provided for research and reference use only. All rights are retained by the journal listed under publisher and/or the creator(s).

Pages

786–800

Issue

3

Volume

102

Citation

Yang Ling; McBurney Denise; Tang Shou-Ching; Carlson Sara G; Horton Walter E Jr, “A novel role for Bcl-2 associated-athanogene-1 (Bag-1) in regulation of the endoplasmic reticulum stress response in mammalian chondrocytes.,” NEOMED Bibliography Database, accessed September 27, 2021, https://neomed.omeka.net/items/show/3033.

Social Bookmarking