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Defining reference genes in Oryza sativa using organ, development, biotic and abiotic transcriptome datasets.

ABSTRACT: BACKGROUND: Reference genes are widely used to normalise transcript abundance data determined by quantitative RT-PCR and microarrays. However, the approaches taken to define reference genes can be variable. Although Oryza sativa (rice) is a widely used model plant and important crop specie, there has been no comprehensive analysis carried out to define superior reference genes. RESULTS: Analysis of 136 Affymetrix transcriptome datasets comprising of 373 genome microarrays from studies in rice that encompass tissue, developmental, abiotic, biotic and hormonal transcriptome datasets identified 151 genes whose expression was considered relatively stable under all conditions. A sub-set of 12 of these genes were validated by quantitative RT-PCR and were seen to be stable under a number of conditions. All except one gene that has been previously proposed as a stably expressed gene for rice, were observed to change significantly under some treatment. CONCLUSION: A new set of reference genes that are stable across tissue, development, stress and hormonal treatments have been identified in rice. This provides a superior set of reference genes for future studies in rice. It confirms the approach of mining large scale datasets as a robust method to define reference genes, but cautions against using gene orthology or counterparts of reference genes in other plant species as a means of defining reference genes.

SUBMITTER: Narsai R

PROVIDER: S-EPMC2923530 | biostudies-literature | 2010

REPOSITORIES: biostudies-literature

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Defining reference genes in Oryza sativa using organ, development, biotic and abiotic transcriptome datasets.

Narsai Reena R Ivanova Aneta A Ng Sophia S Whelan James J

BMC plant biology 20100331

<h4>Background</h4>Reference genes are widely used to normalise transcript abundance data determined by quantitative RT-PCR and microarrays. However, the approaches taken to define reference genes can be variable. Although Oryza sativa (rice) is a widely used model plant and important crop specie, there has been no comprehensive analysis carried out to define superior reference genes.<h4>Results</h4>Analysis of 136 Affymetrix transcriptome datasets comprising of 373 genome microarrays from studi ...[more]

PMID: 20353606

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Project description:BACKGROUND:Oxytropis ochrocephala Bunge, an indigenous locoweed species in China, poses great threats to livestock on grasslands. There is a need for further genetic study in the plants per se, for understanding the basis of its acclimation mechanism in various unfavorable environmental conditions and to implement effective control measures. Quantitative real-time reverse transcription-polymerase chain reaction (qRT-PCR) is the most commonly used method for gene expression analysis. To facilitate gene expression studies and obtain more accurate qRT-PCR data, normalization relative to stable reference genes is required. The aim of this study was to select the most stable reference genes for transcriptional analysis in O. ochrocephala. RESULTS:We selected 12 candidate reference genes, 18S ribosomal RNA (18S RNA), actin2/7 (ACT7), ?-actin (ACTB), actin101 (ACT101), actin11 (ACT11), ?-tubulin (TUB), ?-tubulin (TUA), glyceraldehyde-3-phosphate dehydrogenase-1 (GAPDH1), GAPDH2, metallothionein-like protein (MET), fructose-bisphosphate aldolase (FBA) and histone H3 (HIS), from the transcriptome datasets of O. ochrocephala and determined the suitability by analyzing their expression levels when exposed to a range of abiotic stress conditions. By employing software packages including geNorm, NormFinder and BestKeeper, HIS, ACT7, and ACT101 were assessed as the most suitable set for normalization in all samples. When normalized with the most stable reference genes, the expression patterns of the three target genes were in accordance with those in the transcriptome data, indicating that the reference genes selected in this study are suitable. CONCLUSIONS:The study provided appropriate reference genes for accurate normalization in qRT-PCR analysis in O. ochrocephala and emphasized the importance of validating reference genes for gene expression analysis under specific experimental condition. The usage of inappropriate reference gene would cause misinterpretation.

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Defining reference genes in Oryza sativa using organ, development, biotic and abiotic transcriptome datasets.

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Defining reference genes in Oryza sativa using organ, development, biotic and abiotic transcriptome datasets.

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