Histochemistry and Cell Biology

, Volume 149, Issue 6, pp 655–659 | Cite as

Cell cycle of the enamel knot during tooth morphogenesis

  • Seo-Yoon Jung
  • David William Green
  • Han-Sung JungEmail author
  • Eun-Jung KimEmail author
Short Communication


Enamel knot (EK) is known to be a central organ in tooth development, especially for cusp patterning. To trace the exact position and movement among the inner dental epithelium (IDE) and EK cells, and to monitor the relationship between the EK and cusp patterning, it is essential that we understand the cell cycle status of the EK in early stages of tooth development. In this study, thymidine analogous (IdU, BrdU) staining was used to evaluate the cell cycle phase of the primary EK at the early casp stage (E13.0) and the gerbil embryo (E19) in a developing mouse embryo. The centerpiece of this study was to describe the cell cycle phasing and sequencing during proliferation in the IDE according to the expression of IdU and BrdU following their injection at calculated time points. The interval time between IdU injection and BrdU injection was set at 4 h. As a result, the cell cycle in the IDE of the mouse and gerbil was found to be synchronous. Conversely, the cell cycle in primary EKs of mice was much longer than that of the IDE. Therefore, the difference of cell cycle of the IDE and the EK is related to the diversity of cusp patterning and would provide a new insight into tooth morphogenesis.


Enamel knot Tooth morphogenesis Cusp Cell cycle Mouse Gerbil 



We are grateful to Chengri Li for helping experiments. This study was supported by the Yonsei University College of Dentistry (6-2016-0021).


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Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature 2018

Authors and Affiliations

  1. 1.Division in Anatomy and Developmental Biology, Department of Oral Biology, Oral Science Research Center, BK21 PLUS ProjectYonsei University College of DentistrySeoulSouth Korea
  2. 2.Applied Oral Biosciences, Faculty of DentistryThe University of Hong KongHong KongHong Kong, SAR

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