Related Experiment Video
Updated: Jun 25, 2026

A Morphometric and Cellular Analysis Method for the Murine Mandibular Condyle
Published on: January 11, 2018
The assessment of cell cycle genes in the rat mandibular condyle
Abdullah Al-kalaly1, Charlene Wu, Ricky Wong
1Department of Orthodontics, Faculty of Dentistry, The University of Hong Kong, Hong Kong SAR, China.
Objectives:
We aimed to investigate the expression profile of cell cycle genes in the mandibular condyle on mechanical strain and natural growth, and quantify their expression intensity.
Methods:
Three hundred and fifty 35 days old Sprague-Dawley rats were randomly divided into experimental groups fitted with bite-jumping appliances and control groups. Groups were sacrificed at days 1, 3, 7, 9, 14, 30, and 33. Then, condyles were dissected and total RNA was extracted for microarray analysis.
Results:
Thirty-nine known cell cycle genes were present in the condyle, where Cyclin D1, PCNA, and Wnt5a were differentially expressed. Reverse transcriptase-PCR confirmed that Wnt5a showed a 2-fold increase on experimental day 1, Cyclin D1 showed a 2-fold increase on experimental day 1 and a 3-fold increase on experimental day 14, while PCNA shows 2.2-fold increase both on experimental days 9 and 30. PCNA, Cyclin D1, and Wnt5a were all expressed by cells in both the proliferative layer and erosive zone.
Conclusion:
Mandibular advancement leads to the expression of Cyclin D1 that accelerates entry to the S phase. The increased level of PCNA indicates increased DNA replication of MSC. Then, elevated level of Wnt5a indicates the commitment of MSC to the chondrogenic lineage.
Related Concept Videos
Molecular Factors Affecting Cell Division
Several proteins function as internal regulators to ensure each cell cycle stage is completed faithfully before proceeding to the next. Regulator molecules may act directly or influence the activity or production of other...
Mitogens and the Cell Cycle
The Cell Cycle Control System
The Cell Cycle Control System
Cyclins and cyclin-dependent kinases (Cdks) are the primary cell cycle regulators and function at the cell...
Negative Regulator Molecules
Inhibition of Cdk Activity

