Bivalent histone modifications during tooth development

Abstract

Maps of chromosomal modifications could help scientists to better understand the timing and organization of tooth development. Chromosomal DNA is arranged around proteins called histones, which can be chemically modified at different sites. These modifications can boost or suppress gene activity, and researchers led by Xue-Dong Zhou of Sichuan University set out to examine their involvement in tooth formation. They examined two different histone modifications, one activating and one suppressing, at five different time-points in pulp and enamel development. They found that many sites in the young tooth exhibit both modifications, a state believed to prime cells to respond rapidly to developmental signals. Indeed, immature cells showed gene-activating modifications while more developed enamel and pulp cells tended to show inhibitory modifications. Closer examination of these patterns could lead to a more detailed timeline of tooth development.

Keywords

histone modification / methylation / post-transcriptional modification / tooth development

References

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