Unknown,Transcriptomics,Genomics,Proteomics

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Exon and junction microarrays detect widespread mouse strain- and sex-bias expression differences

ABSTRACT: 71 liver RNA samples from three mouse strains - DBA/2J, C57BL/6J and C3H/HeJ - were profiled using a custom-designed microarray monitoring exon and exon-junction expression of 1,020 genes representing 9,406 exons. Gene expression was calculated via two different methods, using the 3'-most exon probe ("3' gene expression profiling") and using all probes associated with the gene ("whole-transcript gene expression profiling"), while exon expression was determined using exon probes and flanking junction probes that spanned across the neighboring exons("exon expression profiling"). Widespread strain and sex influences were detected using a two-way Analysis of Variance (ANOVA) regardless of the profiling method used. However, over 90% of the genes identified in 3' gene expression profiling or whole transcript profiling were identified in exon profiling, along with 75% and 38% more genes, respectively, showing evidence of differential isoform expression. Overall, 55% and 32% of genes, respectively, exhibited strain- and sex-bias differential gene or exon expression. Keywords: Grouped Hybridization material was generated through a random-priming amplification of poly[A]+ purified RNA using primers with a random sequence at the 3' end and a fixed motif at the 5' end that was optimized to generate strand-specific cDNA copies of full-length mRNA transcripts [32]. Since the region used for exon and junction probe selection is constrained to a smaller region, more probes contain sequence with suboptimal characteristics (e.g. high GC content or higher homology to other genes). The hybridization of cDNA, rather than cRNA as commonly done, partially mitigates this issue due to higher specificity and lower background levels [24]. Hybridization conditions were as previously described [33]. All 71 samples were hybridized in a two-channel experiment, where one channel was a common reference, generated by pooling all 71 samples in equal mass. Array hybridizations were done in duplicate with fluor reversal to systematically correct for Cy3/Cy5 dye bias. Array images were processed as described to obtain background noise, single channel intensity and associated measurement error estimates [34]. Expression changes between samples and pool were quantified as mean log10(expression ratio), and associated error.

ORGANISM(S): Mus musculus

SUBMITTER: Eric Schadt

PROVIDER: E-GEOD-10736 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

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Exon and junction microarrays detect widespread mouse strain- and sex-bias expression differences.

Su Wan-Lin WL Modrek Barmak B GuhaThakurta Debraj D Edwards Stephen S Shah Jyoti K JK Kulkarni Amit V AV Russell Archie A Schadt Eric E EE Johnson Jason M JM Castle John C JC

BMC genomics 20080604

<h4>Background</h4>Studies have shown that genetic and sex differences strongly influence gene expression in mice. Given the diversity and complexity of transcripts produced by alternative splicing, we sought to use microarrays to establish the extent of variation found in mouse strains and genders. Here, we surveyed the effect of strain and sex on liver gene and exon expression using male and female mice from three different inbred strains.<h4>Results</h4>71 liver RNA samples from three mouse s ...[more]

PMID: 18533039

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Dataset Information

Exon and junction microarrays detect widespread mouse strain- and sex-bias expression differences

Publications

Exon and junction microarrays detect widespread mouse strain- and sex-bias expression differences.

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