Gene Expression Profiling during Murine Tooth Development

Abstract

The aim of this study was to describe the expression of genes, including ameloblastin (Ambn), amelogenin X chromosome (Amelx), and enamelin (Enam) during early (pre-secretory) tooth development. The expression of these genes has predominantly been studied at post-secretory stages. Deoxyoligonucleotide microarrays were used to study gene expression during development of the murine first molar tooth germ at 24 h intervals, starting at the 11th embryonic day (E11.5), and up to the 7th day after birth (P7). The profile search function of Spotfire software was used to select genes with similar expression profile as the enamel genes (Ambn, Amelx, and Enam). Microarray results where validated using real-time reverse transcription-polymerase chain reaction (real-time RT-PCR), and translated proteins identified by Western-blotting. In situ localization of the Ambn, Amelx, and Enam mRNAs were monitored from E12.5 to E17.5 using deoxyoligonucleotide probes. Bioinformatics analysis was used to associate biological functions with differentially expressed (DE; p ≤ 0.05) genes. Microarray results showed a total of 4362 genes including Ambn, Amelx, and Enam to be significant DE throughout the time-course. The expression of the three enamel genes was low at pre-natal stages (E11.5–P0) increasing after birth (P1–P7). Profile search lead to isolation of 87 genes with significantly similar expression to the three enamel proteins. These mRNAs were expressed in dental epithelium and epithelium derived cells. Although expression of Ambn, Amelx, and Enam were lower during early tooth development compared to secretory stages enamel proteins were detectable by Western-blotting. Bioinformatic analysis associated the 87 genes with multiple biological functions. Around 35 genes were associated with 15 transcription factors.

Expression of Clu and Tgfb1 during murine tooth development: effects of in‐vivo transfection with anti‐miR‐214

“…Expression of Clu followed a time‐course similar to that of Ambn , Amelx , and Enam , genes known to be highly expressed during the secretory stages of odontogenesis . It has been reported that signals initiating tooth eruption are prevalent at P3‐P5, as genes considered critical for osteoclastogenesis are expressed at these stages .…”

Mapping the global mRNA transcriptome during development of the murine first molar

“…The day of vaginal plug was set to E0.5 Adult mice were sacrificed by cervical dislocation, the embryos or pups by decapitation. Embryos were staged according to the Theiler criteria as described in Landin et al ( 2012 ). Animal housing (Scantainer ventilated cabinet Q-110) had 12 h light/dark cycle.…”

“…More than 4300 mRNAs and some of their translated proteins have, so far, been detected during tooth germ development by microarray, in situ hybridization and immunocytochemistry (Jevnaker and Osmundsen, 2008 ; Landin et al, 2012 ). In a previous study (Landin et al, 2012 ) we used three pre-selected genes (Ambn, Amelx, and Enam) as starting point for profile search and identified 84 differentially expressed genes with a similar expression pattern as these enamel genes. However, the results of this study only show a tinny frame of the big picture of genetic events that occur during murine tooth development.…”

Micro RNAs and Tooth Development; Model for Organogenesis?

“…Tooth development requires the use of more than 2400 genes, integrated both in terms of time and space [3] . Today, we know that during evolution developmental regulatory genes have been conserved to a great degree.…”