Selection and Validation of Appropriate Reference Genes for Quantitative RT-PCR Analysis in Rubia yunnanensis Diels Based on Transcriptome Data

Real-time quantitative polymerase chain reaction (RT-qPCR) has been widely applied in gene expression and transcription abundance analysis because of its high sensitivity, good repeatability, and strong specificity. Selection of relatively stable reference genes is a precondition in order to obtain the reliable analysis results. However, little is known about evaluation of a set of reference genes through scientific experiments in Rubia plants. Here, 15 candidate reference genes were selected from R. yunnanensis transcriptome database and analyzed under abiotic stresses, hormone treatments, and different tissues. Among these 15 candidate reference genes, heterogeneous nuclear ribonucleoprotein (hnRNP), TATA binding protein (TBP), ribosomal protein L5 (RPL5), malate dehydrogenase (MDH), and elongation factor 1-alpha (EF-1α) were indicated as the five most stable reference genes by four statistical programs (geNorm, NormFinder, BestKeeper, and RefFinder). Ultimately, the validity of reference genes was confirmed by normalizing the expression of o-succinylbenzoate-CoA ligase (OSBL) and isochorismate synthase (ICS) involved in the anthraquinone biosynthesis pathway in different tissues and hormone treatments. Meanwhile, four other putative genes involved in the anthraquinone biosynthesis pathway were also normalized with the selected reference genes, which showed similar expression levels with those given by transcriptome data. This work is the first research that aims at a systematic validation on the stability of reference genes selected from R. yunnanensis transcriptome data and will be conducive to analyze gene expression in R. yunnanensis or other Rubia species.

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Comparison of Reliable Reference Genes Following Different Hormone Treatments by Various Algorithms for qRT-PCR Analysis of Metasequoia

International Journal of Molecular Sciences ◽

10.3390/ijms20010034 ◽

2018 ◽

Vol 20 (1) ◽

pp. 34 ◽

Cited By ~ 3

Author(s):

Jing-Jing Wang ◽

Shuo Han ◽

Weilun Yin ◽

Xinli Xia ◽

Chao Liu

Keyword(s):

Gene Expression ◽

Reference Genes ◽

Elongation Factor ◽

Pcr Analysis ◽

Qrt Pcr ◽

Gene Normalization ◽

Accurate Normalization ◽

Suitable Reference ◽

Different Tissues ◽

Gene Expression Levels

Quantitative reverse transcription polymerase chain reaction (qRT-PCR) is the most sensitive technique for evaluating gene expression levels. Choosing appropriate reference genes for normalizing target gene expression is important for verifying expression changes. Metasequoia is a high-quality and economically important wood species. However, few systematic studies have examined reference genes in Metasequoia. Here, the expression stability of 14 candidate reference genes in different tissues and following different hormone treatments were analyzed using six algorithms. Candidate reference genes were used to normalize the expression pattern of FLOWERING LOCUS T and pyrabactin resistance-like 8. Analysis using the GrayNorm algorithm showed that ACT2 (Actin 2), HIS (histone superfamily protein H3) and TATA (TATA binding protein) were stably expressed in different tissues. ACT2, EF1α (elongation factor-1 alpha) and HIS were optimal for leaves treated with the flowering induction hormone solution, while Cpn60β (60-kDa chaperonin β-subunit), GAPDH (glyceraldehyde-3-phosphate dehydrogenase) and HIS were the best reference genes for treated buds. EF1α, HIS and TATA were useful reference genes for accurate normalization in abscisic acid-response signaling. Our results emphasize the importance of validating reference genes for qRT-PCR analysis in Metasequoia. To avoid errors, suitable reference genes should be used for different tissues and hormone treatments to increase normalization accuracy. Our study provides a foundation for reference gene normalization when analyzing gene expression in Metasequoia.

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Selection of Reference Genes for qRT-PCR in Bletilla striata under Heat Stress

International Journal of Agriculture and Biology ◽

10.17957/ijab/15.1700 ◽

2021 ◽

Vol 25 (03) ◽

pp. 547-554

Author(s):

Fang Liang

Keyword(s):

Internal Control ◽

Reference Genes ◽

Elongation Factor ◽

Pcr Analysis ◽

Bletilla Striata ◽

Traditional Chinese Herbal Medicine ◽

Qrt Pcr ◽

Wide Range ◽

Root Tuber ◽

Different Tissues

Bletilla striata (Thunb.) Reihb.f., a traditional Chinese herbal medicine, has attracted increasing attention because of its wide range of applicability to the medical field and chemical industry. B. striata has been identified to be particularly sensitive to high temperatures. Thus, the study of temperature stress on gene transcription is of interest in the field. Use of reliable reference genes is essential for qRT-PCR analysis of genes. However, little information regarding suitable reference genes for the genus Bletilla has been published. In this study, the sequences of seven potential reference genes in B. striata were obtained via a homology cloning strategy. These genes were as follows: glyceraldehydes-3-phosphate dehydrogenase (GAPDH), 18S ribosomal RNA (18S), elongation factor 1 alpha (EF1α), α-tubulin (TUA), β-tubulin (TUB), ubiquitin (UBI), and NAC domain protein (NAC). We then evaluated the stability levels of these transcripts in different tissues (root, tuber, and leaf) exposed to high temperature using three conventional software and comprehensive RefFinder algorithms. The results indicated that 18S and TUB were the best internal control genes among different periods of heat treatment and that a combination of 18S and UBI was the best in different tissues. Altogether, 18S and UBI were identified to be the best reference genes for all the samples, while NAC and TUA were the least stable reference genes. The results will be useful for studies on target gene expression in plants of the Bletilla genus. © 2021 Friends Science Publishers© 2021 Friends Science Publishers© 2021 Friends Science Publishers© 2021 Friends Science Publishers© 2021 Friends Science Publishers© 2021 Friends Science Publishers© 2021 Friends Science Publishers© 2021 Friends Science Publishers© 2021 Friends Science Publishers© 2021 Friends Science Publishers© 2021 Friends Science Publishers© 2021 Friends Science Publishers© 2021 Friends Science Publishers© 2021 Friends Science Publishers© 2021 Friends Science Publishers© 2021 Friends Science Publishers© 2021 Friends Science Publishers© 2021 Friends Science Publishers© 2021 Friends Science Publishers© 2021 Friends Science Publishers© 2021 Friends Science Publishers© 2021 Friends Science Publishers© 2021 Friends Science Publishers© 2021 Friends Science Publishers © 2021 Friends Science Publishers© 2021 Friends Science Publishers© 2021 Friends Science Publishers© 2021 Friends Science Publishers© 2021 Friends Science Publishers© 2021 Friends Science Publishers© 2021 Friends Science Publishers©

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Reference genes for qRT-PCR normalisation in different tissues, developmental stages, and stress conditions of Hypericum perforatum

PeerJ ◽

10.7717/peerj.7133 ◽

2019 ◽

Vol 7 ◽

pp. e7133 ◽

Cited By ~ 4

Author(s):

Wen Zhou ◽

Shiqiang Wang ◽

Lei Yang ◽

Yan Sun ◽

Qian Zhang ◽

...

Keyword(s):

Gene Expression ◽

Candidate Genes ◽

Reference Genes ◽

Hypericum Perforatum ◽

Developmental Stages ◽

Pcr Analysis ◽

Potential Candidate ◽

Qrt Pcr ◽

Expression Studies ◽

Different Tissues

Hypericum perforatum L. is a widely known medicinal herb used mostly as a remedy for depression because it contains high levels of naphthodianthrones, phloroglucinols, alkaloids, and some other secondary metabolites. Quantitative real-time PCR (qRT-PCR) is an optimized method for the efficient and reliable quantification of gene expression studies. In general, reference genes are used in qRT-PCR analysis because of their known or suspected housekeeping roles. However, their expression level cannot be assumed to remain stable under all possible experimental conditions. Thus, the identification of high quality reference genes is essential for the interpretation of qRT-PCR data. In this study, we investigated the expression of 14 candidate genes, including nine housekeeping genes (HKGs) (ACT2, ACT3, ACT7, CYP1, EF1-α, GAPDH, TUB-α, TUB-β, and UBC2) and five potential candidate genes (GSA, PKS1, PP2A, RPL13, and SAND). Three programs—GeNorm, NormFinder, and BestKeeper—were applied to evaluate the gene expression stability across four different plant tissues, four developmental stages and a set of abiotic stress and hormonal treatments. Integrating all of the algorithms and evaluations revealed that ACT2 and TUB-β were the most stable combination in different developmental stages samples and all of the experimental samples. ACT2, TUB-β, and EF1-α were identified as the three most applicable reference genes in different tissues and stress-treated samples. The majority of the conventional HKGs performed better than the potential reference genes. The obtained results will aid in improving the credibility of the standardization and quantification of transcription levels in future expression studies on H. perforatum.

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Identification and Selection of Reference Genes for Quantitative Transcript Analysis in Corydalis yanhusuo

Genes ◽

10.3390/genes11020130 ◽

2020 ◽

Vol 11 (2) ◽

pp. 130 ◽

Cited By ~ 1

Author(s):

Zhenzhen Bao ◽

Kaidi Zhang ◽

Hanfeng Lin ◽

Changjian Li ◽

Xiurong Zhao ◽

...

Keyword(s):

Gene Expression ◽

Reference Genes ◽

Elongation Factor ◽

High Sensitivity ◽

Future Research ◽

Polypyrimidine Tract Binding Protein ◽

Accurate Normalization ◽

Ubiquitin Conjugating Enzyme ◽

Protein Phosphatase 2 ◽

Selection Of

Corydalis yanhusuo is a medicinal plant frequently used in traditional Chinese medicine, which has effective medical effects in many aspects. Real-time polymerase chain reaction (RT-PCR) has been one of the most widely used methods in biosynthesis research due to its high sensitivity and quantitative properties in gene expression analysis. To obtain accurate normalization, reference genes are often selected in advance; however, no reference genes are available in C. yanhusuo. Herein, 12 reference gene candidates, named cyclophilin 2 (CYP2), elongation factor 1-α (EF1-α), protein phosphatase 2 (PP2A), SAND protein family (SAND), polypyrimidine tract-binding protein (PTBP), TIP41-like protein (TIP41), lyceraldehyde-3-phosphate hydrogenase (GAPDH), ubiquitin-conjugating enzyme 9 (UBC9), cyclophilin 1 (CYP1), tubulin beta (TUBA), thioredoxin (YLS8), and polyubiquitin 10 (UBQ10), were selected for stability analysis. After being treated with hormone, UV, salt, metal, oxidative, drought, cold (4 °C), and hot stresses (40 °C), the qRT-PCR data of the selected genes was analyzed with NormFinder, geNorm, and BestKeeper. The result indicated that GAPDH, SNAD, and PP2A were the top three most stable reference genes under most treatments. This study selected and validated reliable reference genes in C. yanhusuo under various environmental conditions, which can provide great help for future research on gene expression normalization in C. yanhusuo.

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Validation of reference genes for accurate normalization by quantitative polymerase chain reaction in sugarcane drought stress studies using two cultivars

Ciência Rural ◽

10.1590/0103-8478cr20180152 ◽

2018 ◽

Vol 48 (11) ◽

Author(s):

Dennis Crystian ◽

Jackeline Terto ◽

José Vieira Silva ◽

Cícero Almeida

Keyword(s):

Gene Expression ◽

Polymerase Chain Reaction ◽

Drought Stress ◽

Reference Genes ◽

Quantitative Polymerase Chain Reaction ◽

Elongation Factor ◽

Chain Reaction ◽

Stress Studies ◽

Accurate Normalization ◽

Polymerase Chain

ABSTRACT: The aim of this study was to analyze the expression of putative reference genes in sugarcane under drought stress. The varieties RB72454 and RB72910 were cultivated and the treatments control and drought stress applied to 135-day-old plants grown under field conditions. The stress level of the plants was measured by rate of photosynthesis, transpiration, and stomatal conductance. For each biological replicate, expression analyses were conducted using quantitative polymerase chain reaction for the genes α-tubulin, β-tubulin, β-actin, cyclophilin, eukaryotic elongation factor 1, glyceraldehyde 3-phosphate dehydrogenase (GAPDH), histone H3 and ubiquitin. Stability was evaluated using the geNorm, NormFinder, and BestKeeper software packages. Among the candidate genes, GAPDH was identified as the most stable in all software, indicating its suitability for gene expression studies in sugarcane undergoing drought stress; the gene β-actin was the second most stable. These findings suggest using GAPDH and β-actin for normalization in relative gene expression in sugarcane.

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Selection and Validation of Reference Genes for qRT-PCR Analysis in the Oil-Rich Tuber Crop Tiger Nut (Cyperus esculentus) Based on Transcriptome Data

International Journal of Molecular Sciences ◽

10.3390/ijms22052569 ◽

2021 ◽

Vol 22 (5) ◽

pp. 2569

Author(s):

Xue Bai ◽

Tao Chen ◽

Yuan Wu ◽

Mingyong Tang ◽

Zeng-Fu Xu

Keyword(s):

Gene Expression ◽

Reference Genes ◽

Developmental Stages ◽

Expression Patterns ◽

Pcr Analysis ◽

Cyperus Esculentus ◽

Transcriptome Data ◽

Qrt Pcr ◽

Below Ground ◽

The Stability

Tiger nut (Cyperus esculentus), a perennial C4 plant of the Cyperaceae family, is an unconventional crop that is distinguished by its oil-rich tubers, which also possesses the advantages of strong resistance, wide adaptability, short life periods, and large biomass. To facilitate studies on gene expression in this species, we identified and validated a series of reference genes (RGs) based on transcriptome data, which can be employed as internal controls for qRT-PCR analysis in tiger nut. Fourteen putative candidate RGs were identified and evaluated across nine different tissues of two cultivars, and the RGs were analyzed using three different algorithms (geNorm, NormFinder, and BestKeeper). The stability rankings of the candidate RGs were merged into consensus lists with RankAggreg. For the below-ground storage organ of tiger nut, the optimal RGs were TUB4 and UCE2 in different developmental stages of tubers. UCE2 and UBL5 were the most stably expressed RGs among all tissues, while Rubisco and PGK exhibited the lowest expression stability. UCE2, UBL5 and Rubisco were compared to normalize the expression levels of the caleosin (CLO) and diacylglycerol acyltransferase 2-2 (DGAT2-2) genes across the same tissues. Our results showed that the RGs identified in this study, which exhibit more uniform expression patterns, may be utilized for the normalization of qRT-PCR results, promoting further research on gene expression in various tissues of tiger nut.

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Selection of the Reference Gene for Expression Normalization in Papaver somniferum L. under Abiotic Stress and Hormone Treatment

Genes ◽

10.3390/genes11020124 ◽

2020 ◽

Vol 11 (2) ◽

pp. 124 ◽

Cited By ~ 1

Author(s):

Zhaoping Zhang ◽

Changjian Li ◽

Junqing Zhang ◽

Fang Chen ◽

Yongfu Gong ◽

...

Keyword(s):

Gene Expression ◽

Reference Gene ◽

Reference Genes ◽

Gene Selection ◽

Quantitative Polymerase Chain Reaction ◽

Elongation Factor ◽

Papaver Somniferum ◽

Protein Subunit ◽

Experimental Conditions ◽

Analgesic Drugs

Papaver somniferum L. is an important medical plant that produces analgesic drugs used for the pain caused by cancers and surgeries. Recent studies have focused on the expression genes involved in analgesic drugs biosynthesis, and the real-time quantitative polymerase chain reaction (RT-qPCR) technique is the main strategy. However, no reference genes have been reported for gene expression normalization in P. somniferum. Herein, nine reference genes (actin (ACT), glyceraldehyde-3-phosphate dehydrogenase (GAPDH), cyclophilin 2 (CYP2), elongation factor 1-alpha (EF-1α), glyceraldehyde-3-phosphate dehydrogenase 2, cytosolic (GAPC2), nuclear cap-binding protein subunit 2 (NCBP2), protein phosphatase 2A (PP2A), TIP41-like protein (TIP41), and tubulin beta chain (TUB)) of P. somniferum were selected and analyzed under five different treatments (cold, drought, salt, heavy metal, and hormone stress). Then, BestKeeper, NormFinder, geNorm, and RefFinder were employed to analyze their gene expression stability. The results reveal that NCBP2 is the most stable reference gene under various experimental conditions. The work described here is the first report regarding on reference gene selection in P. somniferum, which could be used for the accurate normalization of the gene expression involved in analgesic drug biosynthesis.

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Spatio-temporal selection of reference genes in the two congeneric species of Glycyrrhiza

Scientific Reports ◽

10.1038/s41598-020-79298-8 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Yuping Li ◽

Xiaoju Liang ◽

Xuguo Zhou ◽

Yu An ◽

Ming Li ◽

...

Keyword(s):

Gene Expression ◽

Developmental Stage ◽

Reference Genes ◽

Developmental Stages ◽

Individual Factors ◽

Congeneric Species ◽

Spatio Temporal ◽

The Stability ◽

Different Tissues ◽

Selection Of

AbstractGlycyrrhiza, a genus of perennial medicinal herbs, has been traditionally used to treat human diseases, including respiratory disorders. Functional analysis of genes involved in the synthesis, accumulation, and degradation of bioactive compounds in these medicinal plants requires accurate measurement of their expression profiles. Reverse transcription quantitative real-time PCR (RT-qPCR) is a primary tool, which requires stably expressed reference genes to serve as the internal references to normalize the target gene expression. In this study, the stability of 14 candidate reference genes from the two congeneric species G. uralensis and G. inflata, including ACT, CAC, CYP, DNAJ, DREB, EF1, RAN, TIF1, TUB, UBC2, ABCC2, COPS3, CS, R3HDM2, were evaluated across different tissues and throughout various developmental stages. More importantly, we investigated the impact of interactions between tissue and developmental stage on the performance of candidate reference genes. Four algorithms, including geNorm, NormFinder, BestKeeper, and Delta Ct, were used to analyze the expression stability and RefFinder, a comprehensive software, provided the final recommendation. Based on previous research and our preliminary data, we hypothesized that internal references for spatio-temporal gene expression are different from the reference genes suited for individual factors. In G. uralensis, the top three most stable reference genes across different tissues were R3HDM2, CAC and TUB, while CAC, CYP and ABCC2 were most suited for different developmental stages. CAC is the only candidate recommended for both biotic factors, which is reflected in the stability ranking for the spatio (tissue)-temporal (developmental stage) interactions (CAC, R3HDM2 and DNAJ). Similarly, in G. inflata, COPS3, R3HDM2 and DREB were selected for tissues, while RAN, COPS3 and CS were recommended for developmental stages. For the tissue-developmental stage interactions, COPS3, DREB and ABCC2 were the most suited reference genes. In both species, only one of the top three candidates was shared between the individual factors and their interactions, specifically, CAC in G. uralensis and COPS3 in G. inflata, which supports our overarching hypothesis. In summary, spatio-temporal selection of reference genes not only lays the foundation for functional genomics research in Glycyrrhiza, but also facilitates these traditional medicinal herbs to reach/maximize their pharmaceutical potential.

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Selection of reference genes for gene expression analysis in Liriodendron hybrids’ somatic embryogenesis and germinative tissues

Scientific Reports ◽

10.1038/s41598-021-84518-w ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Tingting Li ◽

Weigao Yuan ◽

Shuai Qiu ◽

Jisen Shi

Keyword(s):

Gene Expression ◽

Somatic Embryogenesis ◽

Reference Genes ◽

Gene Selection ◽

Elongation Factor ◽

Reverse Transcription Pcr ◽

Expression Of Genes ◽

Suitable Reference ◽

Functional Analyses ◽

Elongation Factor 1

AbstractThe differential expression of genes is crucial for plant somatic embryogenesis (SE), and the accurate quantification of gene expression levels relies on choosing appropriate reference genes. To select the most suitable reference genes for SE studies, 10 commonly used reference genes were examined in synchronized somatic embryogenic and subsequent germinative cultures of Liriodendron hybrids by using quantitative real-time reverse transcription PCR. Four popular normalization algorithms: geNorm, NormFinder, Bestkeeper and Delta-Ct were used to select and validate the suitable reference genes. The results showed that elongation factor 1-gamma, histone H1 linker protein, glyceraldehyde-3-phosphate dehydrogenase and α-tubulin were suitable for SE tissues, while elongation factor 1-gamma and actin were best for the germinative organ tissues. Our work will benefit future studies of gene expression and functional analyses of SE in Liriodendron hybrids. It is also serves as a guide of reference gene selection in early embryonic gene expression analyses for other woody plant species.

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Current Practices for Reference Gene Selection in RT-qPCR of Aspergillus: Outlook and Recommendations for the Future

Genes ◽

10.3390/genes12070960 ◽

2021 ◽

Vol 12 (7) ◽

pp. 960

Author(s):

Meagan Archer ◽

Jianping Xu

Keyword(s):

Gene Expression ◽

Reference Gene ◽

Reference Genes ◽

Gene Selection ◽

Quantitative Polymerase Chain Reaction ◽

Specific Method ◽

Experimental Conditions ◽

Reference Gene Selection ◽

Physiological Processes ◽

The Stability

Aspergillus is a genus of filamentous fungi with vast geographic and ecological distributions. Species within this genus are clinically, agriculturally and biotechnologically relevant, leading to increasing interest in elucidating gene expression dynamics of key metabolic and physiological processes. Reverse-transcription quantitative Polymerase Chain Reaction (RT-qPCR) is a sensitive and specific method of quantifying gene expression. A crucial step for comparing RT-qPCR results between strains and experimental conditions is normalisation to experimentally validated reference gene(s). In this review, we provide a critical analysis of current reference gene selection and validation practices for RT-qPCR gene expression analyses of Aspergillus. Of 90 primary research articles obtained through our PubMed query, 17 experimentally validated the reference gene(s) used. Twenty reference genes were used across the 90 studies, with beta-tubulin being the most used reference gene, followed by actin, 18S rRNA and glyceraldehyde 3-phosphate dehydrogenase. Sixteen of the 90 studies used multiple reference genes for normalisation. Failing to experimentally validate the stability of reference genes can lead to conflicting results, as was the case for four studies. Overall, our review highlights the need to experimentally validate reference genes in RT-qPCR studies of Aspergillus.

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