AUTHOR=Landin Maria A d., Shabestari Maziar , Babaie Eshrat , Reseland Janne E., Osmundsen Harald 

TITLE=Gene Expression Profiling during Murine Tooth Development

JOURNAL=Frontiers in Genetics

VOLUME=3

YEAR=2012

URL=https://www.frontiersin.org/journals/genetics/articles/10.3389/fgene.2012.00139

DOI=10.3389/fgene.2012.00139

ISSN=1664-8021

ABSTRACT=<p>The aim of this study was to describe the expression of genes, including ameloblastin (<italic>Ambn</italic>), amelogenin X chromosome (<italic>Amelx</italic>), and enamelin (<italic>Enam</italic>) 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 (<italic>Ambn</italic>, <italic>Amelx</italic>, and <italic>Enam</italic>). Microarray results where validated using real-time reverse transcription-polymerase chain reaction (real-time RT-PCR), and translated proteins identified by Western-blotting. <italic>In situ</italic> localization of the <italic>Ambn</italic>, <italic>Amelx</italic>, and <italic>Enam</italic> mRNAs were monitored from E12.5 to E17.5 using deoxyoligonucleotide probes. Bioinformatics analysis was used to associate biological functions with differentially expressed (DE; <italic>p</italic> ≤ 0.05) genes. Microarray results showed a total of 4362 genes including <italic>Ambn</italic>, <italic>Amelx</italic>, and <italic>Enam</italic> 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 <italic>Ambn</italic>, <italic>Amelx</italic>, and <italic>Enam</italic> 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.</p>