Metabolomics,Unknown,Transcriptomics,Genomics,Proteomics

Dataset Information

Cross-species gene expression analysis of species-specific differences in preclinical assessment of pharmaceutical compounds (rat)

ABSTRACT: Significant qualitative and quantitative differences exist between humans and the animal models used in research. However, significant quantitative and qualitative differences exist between humans and the animal models used in research. This is as a result of genetic variation between human and the laboratory animal. Therefore the development of a system that would allow the assessment of all molecular differences between species after drug exposure would have a significant impact on drug evaluation for toxicity and efficacy. Here we describe a cross-species microarray methodology that identifies and selects orthologous probes after cross-species sequence comparison to develop an orthologous cross-species gene expression analysis tool. The assumptions made by the use of this orthologous gene expression strategy for cross-species extrapolation is that; conserved changes in gene expression equate to conserved pharmacodynamic endpoints. This assumption is supported by the fact that evolution and selection have maintained the structure and function of many biochemical pathways over time, resulting in the conservation of many important processes. We demonstrate this difference using a cross-species methodology by investigating species specific differences of the peroxisome proliferator activator receptor (PPAR) alpha in rat and human. Rat primary hepatocytes were treated with 30 µM, 100 µM EMD and 0.1% DMSO as vehicle control. All samples were incubated at 24hr and 72hr intervals before RNA extrations and hybridization onto Affymetrix Rat microarrays.

ORGANISM(S): Rattus norvegicus

SUBMITTER: John Okyere

PROVIDER: E-GEOD-47695 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

ACCESS DATA

Publications

Cross-species gene expression analysis of species specific differences in the preclinical assessment of pharmaceutical compounds.

Okyere John J Oppon Ekow E Dzidzienyo Daniel D Sharma Lav L Ball Graham G

PloS one 20140513 5

Animals are frequently used as model systems for determination of safety and efficacy in pharmaceutical research and development. However, significant quantitative and qualitative differences exist between humans and the animal models used in research. This is as a result of genetic variation between human and the laboratory animal. Therefore the development of a system that would allow the assessment of all molecular differences between species after drug exposure would have a significant impac ...[more]

PMID: 24823806

Similar Datasets

Project description:Although Candida albicans and Candida dubliniensis are most closely related, both species significantly behave differently with respect to morphogenesis and virulence. In order to gain further insight into the divergent routes for morphogenetic adaptation in both species, we investigated qualitative along with quantitative differences in the transcriptomes of both organisms by cDNA deep sequencing. Following genome-associated assembly of sequence reads we were able to generate experimentally verified databases containing 6016 and 5972 genes for C. albicans and C. dubliniensis, respectively. About 95% of the transcriptionally active regions (TARs) contain open reading frames while the remaining TARs most likely represent non-coding RNAs. Comparison of our annotations with publically available gene models for C. albicans and C. dubliniensis confirmed approximately 95% of already predicted genes, but also revealed so far unknown novel TARs in both species. Qualitative cross-species analysis of these databases revealed in addition to 5802 orthologs also 399 and 49 species-specific protein coding genes for C. albicans and C. dubliniensis, respectively. Furthermore, quantitative transcriptional profiling using RNA-Seq revealed significant differences in the expression of orthologs across both species. We defined a core subset of 84 hyphal-specific genes required for both species, as well as a set of 42 genes that seem to be specifically induced during hyphal morphogenesis in C. albicans. Species specific adaptation in C. albicans and C. dubliniensis is governed by individual genetic repertoires but also by altered regulation of conserved orthologs on the transcriptional level. We investigated qualitative along with quantitative differences in the transcriptomes of both organisms by cDNA deep sequencing. In a first step, we reevaluated the in silico predicted gene models by collecting experimental data using FLX - technology for sequencing strand-specific and normalized cDNA libraries derived from blastospores and hyphae. In the second step, quantitative RNA-Seq (GAIIX) was applied to C. albicans hyphal cells and C. dubliniensis blastospore and hyphal cells to complement reevaluation of the gene models with FLX data as well as to measure differential gene expression across the species with two biological replicates.

Project description:The transition between morula and blastocyst stage during preimplantation development represents the first differentiation event of embryogenesis. Morula cells undergo the first cellular specialization and produce two well-defined populations of cells, the trophoblast and the inner cell mass (ICM). Embryonic stem cells (ESCs) with unlimited self-renewal capacity are believed to represent the in vitro counterpart of the ICM. Both mouse and rat ESCs can be derived from the ICM cells, but their in vitro stability differs. In this study we performed a microarray analysis in which we compared the transcriptome of mouse and rat morula, blastocyst, and ICM. This cross-species comparison represents a good model for understanding the differences in derivation and cultivation of ESCs observed in the two species. In order to identify alternative regulation of important molecular mechanisms the investigation of differential gene expression between the two species was extended at the level of signaling pathways, gene families, and single selected genes of interest. Some of the genes differentially expressed between the two species are already known to be important factors in the maintenance of pluripotency in ESCs, like for example Sox2 or Stat3, or play a role in reprogramming somatic cells to pluripotency like c-Myc, Klf4 and p53 and therefore represent interesting candidates to further analyze in vitro in the rat ESCs. This is the first study investigating the gene expression changes during the transition from morula to blastocyst in the rat preimplantation development. Our data show that in the pluripotent pool of cells of the rat and mouse preimplantation embryo substantial differential regulation of genes is present, which might explain the difficulties observed for the derivation and culture of rat ESCs using mouse conditions Casanova EA, Okoniewski MJ, Cinelli P. Cross-Species Genome Wide Expression Analysis during Pluripotent Cell Determination in Mouse and Rat Preimplantation Embryos.PLoS One. 2012;7(10):e47107. doi: 10.1371/journal.pone.0047107. Epub 2012 Oct 15.

Dataset Information

Cross-species gene expression analysis of species-specific differences in preclinical assessment of pharmaceutical compounds (rat)

Publications

Cross-species gene expression analysis of species specific differences in the preclinical assessment of pharmaceutical compounds.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure