Dataset Information

Genetic basis of transcriptome differences between the founder strains of the rat HXB/BXH recombinant inbred panel.

ABSTRACT:

Background

With the advent of next generation sequencing it has become possible to detect genomic variation on a large scale. However, predicting which genomic variants are damaging to gene function remains a challenge, as knowledge of the effects of genomic variation on gene expression is still limited. Recombinant inbred panels are powerful tools to study the cis and trans effects of genetic variation on molecular phenotypes such as gene expression.

Results

We generated a comprehensive inventory of genomic differences between the two founder strains of the rat HXB/BXH recombinant inbred panel: SHR/OlaIpcv and BN-Lx/Cub. We identified 3.2 million single nucleotide variants, 425,924 small insertions and deletions, 907 copy number changes and 1,094 large structural genetic variants. RNA-sequencing analyses on liver tissue of the two strains identified 532 differentially expressed genes and 40 alterations in transcript structure. We identified both coding and non-coding variants that correlate with differential expression and alternative splicing. Furthermore, structural variants, in particular gene duplications, show a strong correlation with transcriptome alterations.

Conclusions

We show that the panel is a good model for assessing the genetic basis of phenotypic heterogeneity and for providing insights into possible underlying molecular mechanisms. Our results reveal a high diversity and complexity underlying quantitative and qualitative transcriptional differences.

SUBMITTER: Simonis M

PROVIDER: S-EPMC3446305 | biostudies-literature | 2012 Apr

REPOSITORIES: biostudies-literature

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Publications

Genetic basis of transcriptome differences between the founder strains of the rat HXB/BXH recombinant inbred panel.

Simonis Marieke M Atanur Santosh S SS Linsen Sam S Guryev Victor V Ruzius Frans-Paul FP Game Laurence L Lansu Nico N de Bruijn Ewart E van Heesch Sebastiaan S Jones Steven J M SJ Pravenec Michal M Aitman Tim J TJ Cuppen Edwin E

Genome biology 20120427 4

<h4>Background</h4>With the advent of next generation sequencing it has become possible to detect genomic variation on a large scale. However, predicting which genomic variants are damaging to gene function remains a challenge, as knowledge of the effects of genomic variation on gene expression is still limited. Recombinant inbred panels are powerful tools to study the cis and trans effects of genetic variation on molecular phenotypes such as gene expression.<h4>Results</h4>We generated a compre ...[more]

PMID: 22541052

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Project description:Post transcriptional modifications of RNA are powerful mechanisms by which eukaryotes expand their genetic diversity. For instance, researchers estimate that most transcripts in humans undergo alternative splicing and alternative polyadenylation. These splicing events produce distinct RNA molecules, which in turn yield distinct protein isoforms and/or influence RNA stability, translation, nuclear export, and RNA/protein cellular localization. Due to their pervasiveness and impact, we hypothesized that alternative splicing and alternative polyadenylation in brain can contribute to a predisposition for voluntary alcohol consumption. Using the HXB/BXH recombinant inbred rat panel (a subset of the Hybrid Rat Diversity Panel), we generated over one terabyte of brain RNA sequencing data (total RNA) and identified novel splice variants (via StringTie) and alternative polyadenylation sites (via aptardi) to determine the transcriptional landscape in the brains of these animals. After establishing an analysis pipeline to ascertain high quality transcripts, we quantitated transcripts and integrated genotype data to identify candidate transcript coexpression networks and individual candidate transcripts associated with predisposition to voluntary alcohol consumption in the two-bottle choice paradigm. For genes that were previously associated with this trait (e.g., Lrap, Ift81, and P2rx4) (Saba et al., Febs. J., 282, 3556-3578, Saba et al., Genes. Brain. Behav., 20, e12698), we were able to distinguish between transcript variants to provide further information about the specific isoforms related to the trait. We also identified additional candidate transcripts associated with the trait of voluntary alcohol consumption (i.e., isoforms of Mapkapk5, Aldh1a7, and Map3k7). Consistent with our previous work, our results indicate that transcripts and networks related to inflammation and the immune system in brain can be linked to voluntary alcohol consumption. Overall, we have established a pipeline for including the quantitation of alternative splicing and alternative polyadenylation variants in the transcriptome in the analysis of the relationship between the transcriptome and complex traits.

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Dataset Information

Genetic basis of transcriptome differences between the founder strains of the rat HXB/BXH recombinant inbred panel.

Background

Results

Conclusions

Publications

Genetic basis of transcriptome differences between the founder strains of the rat HXB/BXH recombinant inbred panel.

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