The transcription factor AP-2 epsilon regulates CXCL1 during cartilage development and in osteoarthritis

Wenke, A. -K. and Niebler, S. and Graessel, S. and Bosserhoff, A. K. (2011) The transcription factor AP-2 epsilon regulates CXCL1 during cartilage development and in osteoarthritis. OSTEOARTHRITIS AND CARTILAGE, 19 (2). pp. 206-212. ISSN 1063-4584, 1522-9653

Full text not available from this repository. (Request a copy)

Abstract

Objective: Recently, the transcription factor AP-2 epsilon was shown to be a regulator of hypertrophy in cartilage and to be differentially expressed in osteoarthritis (OA). However, the only known target gene of AP-2 epsilon up to date is integrin alpha10. To better characterize the function of AP-2 epsilon in cartilage we screened for additional target genes. Design: Promoter analysis, ChIP-assays and electrophoretic mobility shift assay were used to characterize the regulation of a new AP-2 epsilon target gene in detail. Results: In this study, we determined the chemokine CXCL1, already known to be important in osteoarthritis (OA), as a new target gene of AP-2 epsilon. We could confirm that CXCL1 is expressed in chondrocytes and significantly over-expressed in OA-chondrocytes. Transient transfection of chondrocytes with an AP-2 epsilon expression construct led to a significant increase of the CXCL1 mRNA level in these cells. We identified three potential AP-2 binding sites within the CXCL1 promoter and performed luciferase assays, indicating that an AP-2 binding motif (AP-2.2) ranging from position -135 to -144 bp relative to the translation start is responsive to AP-2 epsilon. This result was further addressed by site-directed mutagenesis demonstrating that activation of the CXCL1 promoter by AP-2e is exclusively dependent on AP-2.2. Chromatin immunoprecipitation and electromobility shift assays confirmed the direct binding of AP-2 epsilon to the CXCL1 promoter in OA-chondrocytes at this site. Conclusion: These findings revealed CXCL1 as a novel target gene of AP-2 epsilon in chondrocytes and support the important role of AP-2 epsilon in cartilage. (C) 2010 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.

Item Type: Article
Uncontrolled Keywords: COLLAGEN GENE-EXPRESSION; AP-2 FAMILY; CHONDROCYTE HYPERTROPHY; ARTICULAR-CARTILAGE; MALIGNANT-MELANOMA; DNA-BINDING; GRO-ALPHA; LIMB-BUD; DIFFERENTIATION; CHONDROGENESIS; AP-2 epsilon; CXCL1; Cartilage; Hypertrophic chondrocytes; Osteoarthritis
Subjects: 600 Technology > 610 Medical sciences Medicine
Divisions: Medicine > Lehrstuhl für Orthopädie
Medicine > Lehrstuhl für Pathologie
Depositing User: Dr. Gernot Deinzer
Date Deposited: 26 Jun 2020 07:14
Last Modified: 26 Jun 2020 07:14
URI: https://pred.uni-regensburg.de/id/eprint/21300

Actions (login required)

View Item View Item