A candidate enhancer element responsible for high-level expression of the aggrecan gene in chondrocytes.

Abstract

Aggrecan is the most abundant proteoglycan in cartilage. It contains a lot of negatively charged glycosaminoglycan chains along the core protein, providing a large osmotic swelling pressure within the cartilage. Therefore, the biomechanical properties of cartilage, such as its compressive load-bearing capacity, are highly dependent on the presence of abundant aggrecan in the cartilage matrix. To elucidate the transcriptional mechanism that leads to abundant expression of aggrecan by chondrocytes, we screened for enhancer elements in 130 kb of the aggrecan gene, Agc1, using a reporter assay system that we previously developed. The system is based on co-transfection of candidate enhancer elements and reporter constructs into Swarm rat chondrosarcoma chondrocytes that retain a high level of aggrecan expression. We found an element that might be involved in high-level expression of Agc1 gene in chondrocytes in vivo. The element is located 30 kb upstream of the Agc1 transcription start site.

• Authors: Yuichi Ikeda, Kazuo Ito, Yuichi Izumi, Tamayuki Shinomura
• Journal: Journal of biochemistry (J Biochem) Vol. 156 Issue 1 Pg. 21-8 (Jul 2014) ISSN: 1756-2651 [Electronic] England
• PMID: 24554731 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: © The Authors 2014. Published by Oxford University Press on behalf of the Japanese Biochemical Society. All rights reserved.

Chemical References

• Acan protein, rat
• Aggrecans

Topics

• Aggrecans (genetics)
• Animals
• Chondrocytes (metabolism)
• Enhancer Elements, Genetic (genetics)
• Rats
• Tumor Cells, Cultured