Title:
Molecular control of the trans-differentiation of hypertrophic chondrocyte to osteoblast in skeletal development and growth

 

Speaker:
Kathryn Cheah
School of Biomedical Sciences
The University of Hong Kong
21, Sassoon Rd, Hong Kong
Email: kathycheah(at)hku.hk

 

Abstract:
Maintenance of bone throughout life requires continuous renewal of osteoblasts. Osteoblasts, originating from the perichondrium, accompany vascular invasion and lay down endochondral bone to replace cartilage. Using a genetic recombination lineage tracing approach in mice, we previously reported an additional source of osteoblasts, that hypertrophic chondrocytes (HCs) can become osteogenic cells in fetal and postnatal endochondral bones and persist into adulthood. Moreover, the chondrocyte-to-osteoblast transition also occurs in bone repair. However, the signaling pathways that control the process and the molecular changes during the HC to osteoblast transition are unknown. In my talk I will discuss how Wnt signaling controls fate determination in the HC to osteoblast transition. I will also show how single cell transcriptomics can be used to dissect the lineage hierarchy during the fate transition from HC to osteoblast. The analyses reveal multiple molecular changes including cell cycle re-entry, during the lineage transition.

 

Reference:
L.Yang, K.Y. Tsang, H. C. Tang, D. Chan, K.S.E. Cheah (2014) Hypertrophic chondrocytes can become osteoblasts and osteocytes in endochondral bone formation. Proceedings of the National Academy of Sciences of the United States of America. 111: 12097–12102.
K.Y. Tsang, D. Chan, K.S.E. Cheah (2015). Fate of growth plate hypertrophic chondrocytes: Death or lineage extension? Development, Growth & Differentiation. 57: 179-192.