Selection and Validation of Suitable Reference Genes for RT-qPCR Analysis in Bursaphelenchus Xylophilus

Abstract Quantitative reverse transcription polymerase chain reaction (RT-qPCR) is a powerful technique for studying gene expression, and it is widely used in molecular biology and genetic research. The key to quantitative accuracy depends on the stability of the reference genes used for data normalization under different experimental conditions. The pinewood nematode (PWN; Bursaphelenchus xylophilus) is the causal agent of a devastating disease, the pine wood disease (PWD), demanding extensive and prompt research to understand the molecular mechanism of PWD, but the identification of reference PWN genes for standardized RT-qPCR has not been reported yet. In this study, we have analyzed eight candidate reference genes of PWN under different temperature conditions and at different developmental stages. Delta Ct method, GeNorm, NormFinder, BestKeeper and RefFinder algorithms were used to evaluate the expression stability of these genes. 18SrRNA and HIS were selected for gene expression research under temperature treatments, while EF1γ and 18SrRNA for gene expression studies across different developmental stages. In general, the results indicate that 18SrRNA is the most stable gene for RT-qPCR under different conditions. Finally, we use arginine kinase gene (AK) in different temperature and heat shock protein 90 (HSP90) in different developmental stages to confirm the stability of expression. The systematic analysis of qRT-PCR reference gene selection of B. xylophilus will be helpful for future functional analysis and exploration of genetic resources of B. xylophilus.

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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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Validation of Internal Control Genes for Quantitative Real-Time PCR Gene Expression Analysis in Morchella

Molecules ◽

10.3390/molecules23092331 ◽

2018 ◽

Vol 23 (9) ◽

pp. 2331 ◽

Cited By ~ 10

Author(s):

Qianqian Zhang ◽

Wei Liu ◽

Yingli Cai ◽

A-Feng Lan ◽

Yinbing Bian

Keyword(s):

Gene Expression ◽

Candidate Genes ◽

Expression Analysis ◽

Internal Control ◽

Reference Genes ◽

Gene Expression Analysis ◽

Stable Gene ◽

Experimental Conditions ◽

The Stability ◽

Vacuolar Protein

The reliability of qRT-PCR results depend on the stability of reference genes used for normalization, suggesting the necessity of identification of reference genes before gene expression analysis. Morels are edible mushrooms well-known across the world and highly prized by many culinary kitchens. Here, several candidate genes were selected and designed according to the Morchella importuna transcriptome data. The stability of the candidate genes was evaluated with geNorm and NormFinder under three different experimental conditions, and several genes with excellent stability were selected. The extensive adaptability of the selected genes was tested in ten Morchella species. Results from the three experimental conditions revealed that ACT1 and INTF7 were the most prominent genes in Morchella, CYC3 was the most stable gene in different development stages, INTF4/AEF3 were the top-ranked genes across carbon sources, while INTF3/CYC3 pair showed the robust stability for temperature stress treatment. We suggest using ACT1, AEF3, CYC3, INTF3, INTF4 and INTF7 as reference genes for gene expression analysis studies for any of the 10 Morchella strains tested in this study. The stability and practicality of the gene, vacuolar protein sorting (INTF3), vacuolar ATP synthase (INTF4) and14-3-3 protein (INTF7) involving the basic biological processes were validated for the first time as the candidate reference genes for quantitative PCR. Furthermore, the stability of the reference genes was found to vary under the three different experimental conditions, indicating the importance of identifying specific reference genes for particular conditions.

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Selection and Validation of Candidate Reference Genes for Gene Expression Analysis by RT-qPCR in Rubus

International Journal of Molecular Sciences ◽

10.3390/ijms221910533 ◽

2021 ◽

Vol 22 (19) ◽

pp. 10533

Author(s):

Yaqiong Wu ◽

Chunhong Zhang ◽

Haiyan Yang ◽

Lianfei Lyu ◽

Weilin Li ◽

...

Keyword(s):

Gene Expression ◽

Reference Genes ◽

Gene Selection ◽

Developmental Stages ◽

Functional Genes ◽

Internal Reference ◽

Berry Crops ◽

Differential Gene ◽

Software Programs ◽

The Stability

Due to the lack of effective and stable reference genes, studies on functional genes in Rubus, a genus of economically important small berry crops, have been greatly limited. To select the best internal reference genes of different types, we selected four representative cultivars of blackberry and raspberry (red raspberry, yellow raspberry, and black raspberry) as the research material and used RT-qPCR technology combined with three internal stability analysis software programs (geNorm, NormFinder, and BestKeeper) to analyze 12 candidate reference genes for the stability of their expression. The number of most suitable internal reference genes for different cultivars, tissues, and fruit developmental stages of Rubus was calculated by geNorm software to be two. Based on the results obtained with the three software programs, the most stable genes in the different cultivars were RuEEF1A and Ru18S. Finally, to validate the reliability of selected reference genes, the expression pattern of the RuCYP73A gene was analyzed, and the results highlighted the importance of appropriate reference gene selection. RuEEF1A and Ru18S were screened as reference genes for their relatively stable expression, providing a reference for the further study of key functional genes in blackberry and raspberry and an effective tool for the analysis of differential gene expression.

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Selection and Validation of Reference Genes for RT-qPCR Normalization in Bradysia odoriphaga (Diptera: Sciaridae) Under Insecticides Stress

Frontiers in Physiology ◽

10.3389/fphys.2021.818210 ◽

2022 ◽

Vol 12 ◽

Author(s):

Haiyan Fu ◽

Tubiao Huang ◽

Cheng Yin ◽

Zhenhua Xu ◽

Chao Li ◽

...

Keyword(s):

Gene Expression ◽

Ribosomal Protein ◽

Reference Genes ◽

Gene Selection ◽

Developmental Stages ◽

Resistance Mechanism ◽

Elongation Factor ◽

Expression Stability ◽

Experimental Conditions ◽

Gene Expression Studies

Bradysia odoriphaga (Diptera: Sciaridae) is the most serious root maggot pest which causes substantial damage to the Chinese chive. Organophosphate (OP) and neonicotinoid insecticides are widely used chemical pesticides and play important roles in controlling B. odoriphaga. However, a strong selection pressure following repeated pesticide applications has led to the development of resistant populations of this insect. To understand the insecticide resistance mechanism in B. odoriphaga, gene expression analysis might be required. Appropriate reference gene selection is a critical prerequisite for gene expression studies, as the expression stability of reference genes can be affected by experimental conditions, resulting in biased or erroneous results. The present study shows the expression profile of nine commonly used reference genes [elongation factor 1α (EF-1α), actin2 (ACT), elongation factor 2α (EF-2α), glucose-6-phosphate dehydrogenase (G6PDH), glyceraldehyde-3-phosphate dehydrogenase (GAPDH), ribosomal protein L10 (RPL10), ribosomal protein S3 (RPS3), ubiquitin-conjugating enzyme (UBC), and α-tubulin (TUB)] was systematically analyzed under insecticide stress. Moreover, we also evaluated their expression stability in other experimental conditions, including developmental stages, sexes, and tissues. Five programs (NormFinder, geNorm, BestKeeper, RefFinder, and ΔCt) were used to validate the suitability of candidate reference genes. The results revealed that the most appropriate sets of reference genes were RPL10 and ACT across phoxim; ACT and TUB across chlorpyrifos and chlorfluazuron; EF1α and TUB across imidacloprid; EF1α and EF2α across developmental stages; RPL10 and TUB across larvae; EF1α and ACT across tissues, and ACT and G6PDH across sex. These results will facilitate the standardization of RT-qPCR and contribute to further research on B. odoriphaga gene function under insecticides stress.

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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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Selecting and validating reference genes for quantitative real-time PCR in Plutella xylostella (L.)

Genome ◽

10.1139/gen-2017-0176 ◽

2018 ◽

Vol 61 (5) ◽

pp. 349-358 ◽

Cited By ~ 6

Author(s):

Yanchun You ◽

Miao Xie ◽

Liette Vasseur ◽

Minsheng You

Keyword(s):

Gene Expression ◽

Real Time ◽

Plutella Xylostella ◽

Real Time Pcr ◽

Reference Genes ◽

Developmental Stages ◽

Quantitative Real Time Pcr ◽

Experimental Conditions ◽

Expression Studies ◽

Gene Expression Studies

Gene expression analysis provides important clues regarding gene functions, and quantitative real-time PCR (qRT-PCR) is a widely used method in gene expression studies. Reference genes are essential for normalizing and accurately assessing gene expression. In the present study, 16 candidate reference genes (ACTB, CyPA, EF1-α, GAPDH, HSP90, NDPk, RPL13a, RPL18, RPL19, RPL32, RPL4, RPL8, RPS13, RPS4, α-TUB, and β-TUB) from Plutella xylostella were selected to evaluate gene expression stability across different experimental conditions using five statistical algorithms (geNorm, NormFinder, Delta Ct, BestKeeper, and RefFinder). The results suggest that different reference genes or combinations of reference genes are suitable for normalization in gene expression studies of P. xylostella according to the different developmental stages, strains, tissues, and insecticide treatments. Based on the given experimental sets, the most stable reference genes were RPS4 across different developmental stages, RPL8 across different strains and tissues, and EF1-α across different insecticide treatments. A comprehensive and systematic assessment of potential reference genes for gene expression normalization is essential for post-genomic functional research in P. xylostella, a notorious pest with worldwide distribution and a high capacity to adapt and develop resistance to insecticides.

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Selection and validation of reference genes for quantitative gene expression analyses in persimmon (Diospyros kaki Thunb.) using real-time quantitative PCR

Biologia Futura ◽

10.1556/019.70.2019.24 ◽

2019 ◽

Vol 70 (4) ◽

pp. 261-267

Author(s):

Gaigai Du ◽

Liyuan Wang ◽

Huawei Li ◽

Peng Sun ◽

Jianmin Fu ◽

...

Keyword(s):

Gene Expression ◽

Real Time ◽

Reference Gene ◽

Reference Genes ◽

Developmental Stages ◽

Suitable Reference Gene ◽

Diospyros Kaki ◽

Stable Gene ◽

Expression Studies ◽

Gene Expression Studies

Background and aims Persimmon (Diospyros kaki) is an economically important fruit tree species with complex flowering characteristics. To obtain accurate expression pattern analysis results, it is vital to select a reliable gene for the normalization of real-time quantitative polymerase chain reaction data. The aim of this study was to identify the optimal internal control gene among six candidate genes for gene expression analysis in different persimmon organs and developmental stages. Materials and methods This analysis was conducted using geNorm and NormFinder software to show differences in the stability of the six reference genes among tissues and floral developmental stages of the same plant. Results Although genes that exhibited moderate expression in NormFinder revealed slightly different expression stabilities than those obtained by geNorm, both sets of results showed that GAPDH was the best reference gene in different organs and floral buds at different developmental stages, whereas 18SrRNA was the least stable gene. Conclusions Based on the overall ranking, GAPDH is the most suitable reference gene and is highly recommended for gene expression studies in different organs and different developmental stages of persimmon. This study provides useful reference data for future gene expression studies and will contribute to improving the accuracy of gene expression results in persimmon.

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Reference gene selection and evaluation for expression analysis using qRT-PCR in Galeruca daurica (Joannis)

Bulletin of Entomological Research ◽

10.1017/s0007485316000948 ◽

2016 ◽

Vol 107 (3) ◽

pp. 359-368 ◽

Cited By ~ 12

Author(s):

Y. Tan ◽

X.-R. Zhou ◽

B.-P. Pang

Keyword(s):

Reference Gene ◽

Reference Genes ◽

Target Genes ◽

Gene Selection ◽

Developmental Stages ◽

Pcr Analysis ◽

Experimental Conditions ◽

Reference Gene Selection ◽

Functional Studies ◽

Qrt Pcr

AbstractQuantitative real-time PCR (qRT-PCR) has been used extensively to analyze gene expression and decipher gene function. To obtain the optimal and stable normalization factors for qRT-PCR, selection and validation of reference genes should be conducted in diverse conditions. In insects, more and more studies confirmed the necessity and importance of reference gene selection. In this study, eight traditionally used reference genes in Galeruca daurica (Joannis) were assessed, using qRT-PCR, for suitability as normalization genes under different experimental conditions using four statistical programs: geNorm, Normfinder, BestKeeper and the comparative ΔCt method. The genes were ranked from the most stable to the least stable using RefFinder. The optimal suite of recommended reference genes was as follows: succinate dehydrogenase (SDHA) and tubulin-alpha (TUB-α) for temperature-treated larvae; ribosomal protein L32, SDHA and glutathione S-transferase were best for all developmental stages; ACT and TUB-α for male and female adults; SDHA and TUB-α were relatively stable and expressed in different tissues, both diapause and non-diapause adults. Reference gene evaluation was validated using expression of two target genes: the P450 CYP6 gene and the heat shock protein gene Hsp70. These results confirm the importance of custom reference gene selection when studies are conducted under diverse experimental conditions. A standardized qRT-PCR analysis procedure for gene functional studies is provided that could be useful in studies on other insect species.

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Evaluation of putative reference genes for quantitative real-time PCR normalization inLilium regaleduring development and under stress

PeerJ ◽

10.7717/peerj.1837 ◽

2016 ◽

Vol 4 ◽

pp. e1837 ◽

Cited By ~ 15

Author(s):

Qiang Liu ◽

Chi Wei ◽

Ming-Fang Zhang ◽

Gui-Xia Jia

Keyword(s):

Gene Expression ◽

Heat Stress ◽

Real Time ◽

Quantitative Pcr ◽

Biotic Stress ◽

Reference Genes ◽

Developmental Stages ◽

Real Time Quantitative Pcr ◽

The Stability ◽

Experimental Treatments

Normalization to reference genes is the most common method to avoid bias in real-time quantitative PCR (qPCR), which has been widely used for quantification of gene expression. Despite several studies on gene expression,Lilium, and particularlyL. regale, has not been fully investigated regarding the evaluation of reference genes suitable for normalization. In this study, nine putative reference genes, namely18S rRNA,ACT,BHLH,CLA,CYP,EF1,GAPDH,SANDandTIP41, were analyzed for accurate quantitative PCR normalization at different developmental stages and under different stress conditions, including biotic (Botrytis elliptica), drought, salinity, cold and heat stress. All these genes showed a wide variation in their Cq (quantification Cycle) values, and their stabilities were calculated by geNorm, NormFinder and BestKeeper. In a combination of the results from the three algorithms,BHLHwas superior to the other candidates when all the experimental treatments were analyzed together;CLAandEF1were also recommended by two of the three algorithms. As for specific conditions,EF1under various developmental stages,SANDunder biotic stress,CYP/GAPDHunder drought stress, andTIP41under salinity stress were generally considered suitable. All the algorithms agreed on the stability ofSANDandGAPDHunder cold stress, while onlyCYPwas selected under heat stress by all of them. Additionally, the selection of optimal reference genes under biotic stress was further verified by analyzing the expression level ofLrLOXin leaves inoculated withB. elliptica. Our study would be beneficial for future studies on gene expression and molecular breeding ofLilium.

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Identification and Validation of Reference Genes for Gene Expression Analysis in Different Development Stages of Amylostereum areolatum

Frontiers in Microbiology ◽

10.3389/fmicb.2021.827241 ◽

2022 ◽

Vol 12 ◽

Author(s):

Ningning Fu ◽

Jiaxing Li ◽

Ming Wang ◽

Lili Ren ◽

Shixiang Zong ◽

...

Keyword(s):

Gene Expression ◽

Reference Genes ◽

Growth And Development ◽

Target Genes ◽

Quantitative Polymerase Chain Reaction ◽

Growth Stages ◽

Experimental Conditions ◽

Development Stages ◽

Symbiotic Fungus ◽

The Stability

A strict relationship exists between the Sirex noctilio and the Amylostereum areolatum, which is carried and spread by its partner. The growth and development of this symbiotic fungus is key to complete the life history of the Sirex woodwasp. Real-time quantitative polymerase chain reaction (RT-qPCR) is used to measure gene expression in samples of A. areolatum at different growth stages and explore the key genes and pathways involved in the growth and development of this symbiotic fungus. To obtain accurate RT-qPCR data, target genes need to be normalized by reference genes that are stably expressed under specific experimental conditions. In our study, the stability of 10 candidate reference genes in symbiotic fungal samples at different growth and development stages was evaluated using geNorm, NormFinder, BestKeeper, delta Ct methods, and RefFinder. Meanwhile, laccase1 was used to validate the stability of the selected reference gene. Under the experimental conditions of this study, p450, CYP, and γ-TUB were identified as suitable reference genes. This work is the first to systematically evaluate the reference genes for RT-qPCR results normalization during the growth of this symbiotic fungus, which lays a foundation for further gene expression experiments and understanding the symbiotic relationship and mechanism between S. noctilio and A. areolatum.

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