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Updated: Apr 20, 2026
07:23
Culture of Murine Embryonic Metatarsals: A Physiological Model of Endochondral Ossification
Published on: December 3, 2016
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ERK1 and ERK2 regulate chondrocyte terminal differentiation during endochondral bone formation
Zhijun Chen1, Susan X Yue, Guang Zhou
1Department of Orthopaedics, Case Western Reserve University, Cleveland, OH, USA.
Summary
ERK1 and ERK2 signaling are crucial for chondrocyte terminal differentiation and bone growth. Deleting these kinases impairs growth plate development and may contribute to enchondroma formation in metachondromatosis.
Area of Science:
- Cell Biology
- Developmental Biology
- Genetics
Background:
- Chondrocytes in epiphyseal cartilage undergo terminal differentiation and apoptosis.
- ERK1 and ERK2 signaling pathways play roles in cellular processes, including differentiation.
Purpose of the Study:
- To investigate the role of ERK1 and ERK2 in chondrocyte terminal differentiation.
- To explore the link between ERK signaling and skeletal disorders like metachondromatosis.
Main Methods:
- Generated conditional knockout mice (cKOosx) lacking ERK1 and ERK2 in hypertrophic chondrocytes.
- Performed histological analysis, in situ hybridization, and quantitative real-time PCR.
- Conducted transient transfection experiments in a rat chondrosarcoma cell line.
Main Results:
- cKOosx mice exhibited shorter long bones and expanded hypertrophic chondrocyte zones.
- Expression of Matrix metalloproteinase-13 (Mmp13) and Osteopontin was significantly decreased.
- MEK1-ERK signaling activated the Osteopontin promoter, partly via Egr1 and Egr2 transcription factors.
- Enchondroma-like lesions were observed in cKOosx mice, suggesting a link to metachondromatosis.
Conclusions:
- ERK1 and ERK2 signaling is essential for chondrocyte terminal differentiation.
- Impaired ERK signaling may contribute to enchondroma development in metachondromatosis.
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