Microarray expression profiling of mRNAs in the developing murine first molar tooth ge
Ontology highlight
ABSTRACT: The global gene expression of murine tooth germs dissected at various stages of tooth development was investigated. A list of genes differentialy expressed throughout the various time points was submitted to bioinformatic analysis using Ingenuity Pathway Analysis (IPA) to identify significant associations between clusters of genes found to be differentially expressed and signalling or canonical pathways or molecular/cellular functions. This approach was also used with clusters of genes isolated using the profile search function of Spotfire.). The study entailed a total of 58 dual-labeled/two-chanel microarrays.The results, encompassing at least triplicate microarray data at each time-point, were treated as single colored arrays. The resulting expression data was subsequently assembled into a single data file, facilitating analysis of the time-course of expression profiles of expressed genes.
Project description:Embryologically the tooth is derived from both the ectoderm and neural crest (ectomesenchyme). It is often used as a model to study how epithelialmesenchymal interactions can control differentiation and morphogenesis. During early development organs of ectodermal origin share both a set of signalling molecules and exhibit common morphological features, subsequently proceeding along separate developmental programs.<br><br>Tooth development is a continuous process that can be divided into the initiation -, bud -, cap -, and bell-stages. In mice, tooth development begins at embryonic day 11.5 (E11.5), by thickening of the dental epithelium, while mineralization of enamel and dentin in first molar starts at postnatal day 0 (P0) (5). A multistep and complex process of the gene expression are involved in the early stage of tooth development. So far expression of more than 1300 genes and/or proteins have been detected during tooth germ development by microarrays/immunocytochemistry/in situ hybridization. Studies with mutant mice have identified a number of genes that regulate tooth development and morphology. For example, deficiency of Lef-1 or P63 arrests tooth development at early stages. Deficiency of Msx1 or Pax9 results in arrest of tooth development at the bud stage , while deficiency of Runx2/Cbfa1 or Sp3 inhibits cyto-differentiation of ameloblasts and/or odontoblasts. Shh is required for normal growth and morphogenesis, but is not essential for cyto-differentiation of the ameloblast and odontoblast populations. Ameloblastin and amelogenin knock-out mice develop severe enamel hypoplasia with abnormal ameloblast differentiation. <br><br>Recently, new connections between retinoid metabolism and PPAR responses have been identified. It has also been shown that endogenous retinoic acid is necessary for the initiation of odontogenesis , and that some of the genes that catalyze the oxidation of retinaldehyde into retinoic acid, exhibit distinct patterns of expression in developing murine teeth. Little is known about functions of PPAR-a as regards tooth germs or mature teeth. It is, however, likely that mitochondrial oxidative metabolism well as fatty acid metabolism is enhanced in late odontogenesis. These are metabolic activities which in other tissues are stimulated by PPAR-a agonists.<br><br>For this reason it was of interest to carry out comparative gene expression profiling of the first molar tooth germs of PPAR-a knock-out mouse and of the corresponding wild-type mice. The results suggest marked differences in gene expression, parts of which may be associated with an observed hypomineralization of enamel in the mature PPAR-a knock-out murine tooth.
Project description:Effects of furanone on global gene expression. CD-1mice were treated with compond A B or C for 21 days. The compoud was administered orally to each mouse using a gastric sonde.The researcher was not previously informed about wich compound was the control, this to ensure impartiality during the experiment and the outcoume of the results.
Project description:Sequenced samples are cultured posterior parts of the first mouse molar tooth primordia. RNA sequencing was performed based on explants after 0, 16 or 24 hours of in vitro culture respectively, with aim to define candidate genes playing a role in the tooth germ development.
Project description:The goals of this study are to identify in vivo downstream targets of Yap through NGS-derived tooth germ transcriptome profiling. The mRNA profiles of wild-type, Yap conditional knockout (CKO) and YAP transgenic (Tg) mouse tooth germs at embryonic day 14.5 were generated by deep sequencing using Illumina Hiseq2000. The sequence reads that passed quality filters were analyzed at the transcript isoform level via DNAnexus. The validation was performed through qRT–PCR and in situ hybrydization. A set of Hox genes were differentially expression in Yap CKO and YAP Tg mouse tooth germs, demonstating concurrent expression changes with Yap transcripts. This study provides a platform to systematically identify in vivo downstream targets of genes of interest. The mRNA profiles of wild type, Yap CKO and YAP Tg mouse tooth germs at embryonic day 14.5 were generated by deep sequencing using Illumina Hiseq.
Project description:Label free: The aim of project is to identify the proteins that may have a role in the inductive signal of mesenchymal cells. Protein identification and quantitively compare the proteins from the following samples: 1- Exosomes purified from embryonic mesenchymal cells of tooth germ after overnight culture in 2D and 3D conditions 2- Secretome of embryonic mesenchymal cells of tooth germ after overnight 3D culture. 3- Embryonic mesenchymal cells from tooth germ- fresh frozen as pellet TMT Samples 10.5 and 14.5 are exosomes derived from immortalized cell line and different stages of tooth embryonic development. These sets of samples were seeded in well plate. The embryonic samples are a pool of 6 biological replicates. The aim is to identify the different proteins between these stages as well as the cell line.
Project description:One of the key questions in developmental biology is how from universally shared molecular mechanisms and pathways, is it possible to generate organs displaying similar or complementary functions, with a wide range of different shapes or tissue organization? The dentition represents a valuable system to address the issues of differential molecular signatures generating specific tooth types. We performed a comparative transcriptomic analysis of developing murine lower incisors, mandibular molars and maxillary molars at the developmental cap stage (E14.5) prior to recognizable tooth shape and cusp pattern. We compared gene expression profiles in developing murine lower incisor and molars, as well as between the lower and upper (mandibular and maxillary) first molars
Project description:Little is known about the role of cell-cell adhesion in the development of mineralized tissues. Here we report that PERP, a tetraspan membrane protein essential for epithelial integrity, is a critical regulator of enamel formation. Perp is necessary for proper cell attachment and gene expression during tooth development, and its expression is controlled by P63, a master regulator of stratified epithelial development. During enamel formation, PERP is localized to the interface between the enamel-producing ameloblasts and the stratum intermedium (SI), a layer of cells subjacent to the ameloblasts. Perp-null mice display dramatic enamel defects, which are caused, in part, by the detachment of ameloblasts from the SI. Microarray analysis comparing gene expression in teeth of wild-type and Perp-null mice identified several differentially expressed genes during enamel formation. Analysis of these genes in ameloblast-derived LS8 cells upon knock down of PERP confirmed the role for PERP in the regulation of gene expression. Together, our data show that PERP is necessary for the integrity of the ameloblast-SI interface and that the lack of Perp causes downregulation of genes that are critical for proper enamel formation. Two-condition experiment, RNA isolated from WT vs. Perp-null lower 1st molars. Biological replicates: 3 control replicates, 3 mutant replicates.
Project description:The RSK2 gene is responsible for Coffin-Lowry syndrome, an X-linked monogenic disease associating severe learning deficit andassociated to typical facial and digital abnormalities and skeletal changes. Craniofacial and dental anomalies encountered in this rare disease have been poorly characterized. In this study we explore, through X-Ray microtomographic analysis, the variable craniofacial dysmorphism and dental anomalies present in Rsk2 knockout mice, an animal model of Coffin-Lowry syndrome, as well as in triple Rsk1,2,3 knockout mutants. We report in these mutants the occurrence of a surpernumerary tooth mesial to the first molar. This highly penetrant phenotype is considered as a remnant of evolutionary lost teeth. This possibly leads to the significant reduction of the maxillary diastema. Abnormalities of molar shape were almost restricted to the mesial part of both upper and lower first molars (M1). We also report an expression analysis of the four Rsk genes (Rsk1, 2, 3 and 4) at various stages of odontogenesis in wild-type (WT) mice. Rsk2 was mainly expressed in the mesenchymal, neural crest derived compartment, correlating with proliferative areas of the developing teeth and consistent with a biological function of RSK2 in cell cycle control and cell growth, which when invalidated could be responsible for the dental phenotype. In an attempt to unravel the molecular pathways involved in the genesis of these dental defects, we performed a comparative transcriptomic (DNA microarray) analysis of mandibular wild-type versus Rsk2-/Y molars, and further demonstrated a misregulation of selected genes, using a Rsk2 shRNA knock-down strategy in molar tooth germs cultured in vitro.
Project description:Wistar rats were treated with either PFOA or 8:2 FTOH for 10 days with the following doses, 3, 10 or 25 mg/kg Bwt, followed by one recovery day. The treatment was given daily by i.p. injections. The rats were humanly sacrificed by decapitation, and the liver was immediatly dissected and divided, one piece of the liver was sumerged in RNALater (for use in microarray and realtime experiments) and the other piece of liver was submerged in cold buffer(for ezymatic assays). Pentadecafluorooctanoic (Perfluorooctanoic acid, PFOA) acid is an industrial surfactant. 8:2 FTOH is a fluorotelomer alcohol.