Evaluation of Reference Genes for Transcriptional Profiling in Two Cockroach Models

The German cockroach, Blattella germanica, and the American cockroach, Periplaneta americana are the most common and synanthropic household pests of interest to public health. While they have increasingly served as model systems in hemimetabolous insects for studying many biological issues, there is still a lack of stable reference gene evaluation for reliable quantitative real-time PCR (qPCR) outputs and functional genomics. Here, we evaluated the expression variation of common insect reference genes, including the historically used actin, across various tissues and developmental stages, and also under experimental treatment conditions in these two species by using three individual algorithms (geNorm, BestKeeper, and NormFinder) and a comprehensive program (RefFinder). RPL32 in B. germanica and EF1α in P. americana showed the overall lowest variation among all examined samples. Based on the stability rankings by RefFinder, the optimal but varied reference genes under specific conditions were selected for qPCR normalization. In addition, the combination of RPL32 and EF1α was recommended for all the tested tissues and stages in B. germanica, whereas the combination of multiple reference genes was unfavorable in P. americana. This study provides a condition-specific resource of reference gene selection for accurate gene expression profiling and facilitating functional genomics in these two important cockroaches.

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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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Reference Gene Selection for miRNA qRT-PCR Analysis in Lily

10.21203/rs.3.rs-102523/v1 ◽

2020 ◽

Author(s):

Qian Zhang ◽

Xue Gao ◽

Lian-Juan Wang ◽

Yu-Qian Zhao ◽

Gui-Xia Jia

Keyword(s):

Reference Gene ◽

Stress Responses ◽

Reference Genes ◽

Gene Selection ◽

Developmental Stages ◽

Pcr Analysis ◽

Critical Element ◽

Biotic And Abiotic Stress ◽

Experimental Conditions ◽

Qrt Pcr

Abstract Background: The selection of reliable reference genes is a critical element for obtaining accurate gene expression data to assess quantitative real-time polymerase chain reaction (qRT-PCR) performance. It is critical to use suitable reference genes in miRNA qRT-PCR because of short amplification products and large differences in the expression levels of target miRNAs involved in some biological processes. However, in lily, which exhibits a large complex genome but lacks a reference, the available miRNA reference genes for use in qRT-PCR under various treatment conditions are limited, and their reliability has rarely been systematically evaluated.Results: In this study, 8 candidate reference genes, including three classic housekeeping genes and five potential miRNAs from the miRNA library of L. × formolongi, were selected and assessed for expression stability utilizing the BestKeeper, geNorm and Normfinder tools, together with the Delta Ct method, across a diverse set of biotic and abiotic experimental conditions (developmental stages, tissues, heat stress and pathogen defence) to determine the best reference gene(s) for L. × formolongi and L. regale. The final ranking was reordered by using RankAggreg, and the results showed that the novel miRNA PC-3p-67_108977 and the conserved miRNAs miR399a, miR399a and U6 were the most stable genes for L. × formolongi and L. regale, respectively, under all tested experimental conditions. Additionally, PC-3p-67_108977 and U6 were the most suitable genes for qRT-PCR studies in lily.Conclusions: This study provides a comprehensive evaluation of the reliability of reference genes for miRNA studies on development and biotic and abiotic stress responses in different lilies. These results will be beneficial for miRNA identification and functional studies of lilies in the future.

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Identification and validation of potential reference gene for effective dsRNA knockdown analysis in Chilo partellus

Scientific Reports ◽

10.1038/s41598-019-49810-w ◽

2019 ◽

Vol 9 (1) ◽

Cited By ~ 3

Author(s):

Olawale Samuel Adeyinka ◽

Bushra Tabassum ◽

Idrees Ahmad Nasir ◽

Iqra Yousaf ◽

Imtiaz Ahmad Sajid ◽

...

Keyword(s):

Reference Gene ◽

Chilo Partellus ◽

Reference Genes ◽

Gene Selection ◽

Developmental Stages ◽

Stable Reference Gene ◽

Suitable Reference Gene ◽

Potential Reference Gene ◽

Alternate Control ◽

Suitable Reference

Abstract Chilo partellus is an invasive polyphagous pest that has not been effectively managed with chemical pesticides. To select potential dsRNAs for use in an alternate control strategy, it is crucial to identify and evaluate stable reference genes for knockdown expression studies. This study evaluates the expression stability of seven candidate reference genes in C. partellus larvae fed on crude bacterially-expressed dsRNAs and purified dsRNAs at different time intervals, as well as the developmental stages and sexes. The expression stabilities of the reference genes were evaluated with different software programmes, such as BestKeeper, NormFinder, deltaCt, geNorm, and RefFinder. The overall results rank ELF as the most stably expressed reference gene when larvae were fed with crude bacteria-induced dsRNAs and purified dsRNA. However, Tubulin and HSP70 were more stable under different developmental stages and sexes. The expression levels of larvae that were fed crude bacteria-induced dsRNAs of Chitinase and Acetylcholinesterase were normalized with the four most stable reference genes (ELF, HSP70, V-ATPase and Tubulin) and the least stable reference gene (18S and HSP70) based on the geNorm algorithm. The least stable reference gene showed inconsistent knockdown expression, thereby confirming that the validation of a suitable reference gene is crucial to improve assay accuracy for dsRNA-targeted gene selection in C. partellus.

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Reference gene selection for transcriptional profiling in Cryptocercus punctulatus, an evolutionary link between Isoptera and Blattodea

Scientific Reports ◽

10.1038/s41598-020-79030-6 ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Zhen Li ◽

Xiangrui Li ◽

Qingwen Zhang ◽

Ling Yuan ◽

Xuguo Zhou

Keyword(s):

Reference Gene ◽

Target Genes ◽

Gene Selection ◽

Developmental Stages ◽

Expression Profiles ◽

Transcriptional Profiling ◽

Housekeeping Genes ◽

Experimental Conditions ◽

Qpcr Analysis ◽

Cryptocercus Punctulatus

AbstractThe subsocial life style and wood-feeding capability of Cryptocercus gives us an evolutionary key to unlock some outstanding questions in biology. With the advent of the Genomics Era, there is an unprecedented opportunity to address the evolution of eusociality and the acquisition of lignocellulases at the genetic level. However, to quantify gene expression, an appropriate normalization strategy is warranted to control for the non-specific variations among samples across different experimental conditions. To search for the internal references, 10 housekeeping genes from a gut transcriptome of a wood-feeding cockroach, Cryptocercus punctulatus, were selected as the candidates for the RT-qPCR analysis. The expression profiles of these candidates, including ACT, EF1α, GAPDH, HSP60, HSP70, αTUB, UBC, RPS18, ATPase and GST, were analyzed using a panel of analytical tools, including geNorm, NormFinder, BestKeeper, and comparative ΔCT method. RefFinder, a comprehensive ranking system integrating all four above-mentioned algorithms, rated ACT as the most stable reference gene for different developmental stages and tissues. Expression analysis of the target genes, Hex-1 and Cell-1, using the most or the least appropriate reference genes and a single or multiple normalizers signified this research. Our finding is the first step toward establishing a standardized RT-qPCR analysis in Cryptocercus.

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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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Identification of the most suitable reference gene for gene expression studies with development and abiotic stress response in Bromus sterilis

Scientific Reports ◽

10.1038/s41598-021-92780-1 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Madhab Kumar Sen ◽

Kateřina Hamouzová ◽

Pavlina Košnarová ◽

Amit Roy ◽

Josef Soukup

Keyword(s):

Reference Gene ◽

Herbicide Resistance ◽

Reference Genes ◽

Gene Selection ◽

High Yield ◽

Suitable Reference Gene ◽

Grass Species ◽

Experimental Conditions ◽

Qrt Pcr ◽

Suitable Reference

AbstractBromus sterilis is an annual weedy grass, causing high yield losses in winter cereals. Frequent use of herbicides had led to the evolution of herbicide resistance in this species. Mechanisms underlying herbicide resistance in B. sterilis must be uncovered because this problem is becoming a global threat. qRT-PCR and the next-generation sequencing technologies can elucidate the resistance mechanisms. Although qRT-PCR can calculate precise fold changes, its preciseness depends on the expression of reference genes. Regardless of stable expression in any given condition, no gene can act as a universal reference gene. Hence, it is necessary to identify the suitable reference gene for each species. To our knowledge, there are no reports on the suitable reference gene in any brome species so far. Thus, in this paper, the stability of eight genes was evaluated using qRT-PCR experiments followed by expression stability ranking via five most commonly used software for reference gene selection. Our findings suggest using a combination of 18S rRNA and ACCase to normalise the qRT-PCR data in B. sterilis. Besides, reference genes are also recommended for different experimental conditions. The present study outcomes will facilitate future molecular work in B. sterilis and other related grass species.

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Comparative Transcriptomics Reveals the Expression Differences Between Four Developmental Stages of American Cockroach (Periplaneta americana)

DNA and Cell Biology ◽

10.1089/dna.2018.4578 ◽

2019 ◽

Vol 38 (10) ◽

pp. 1078-1087

Author(s):

Chenjuan Zeng ◽

Wujiao Li ◽

Qi Liao ◽

Tingting Yan ◽

Kaisun Wang ◽

...

Keyword(s):

Periplaneta Americana ◽

Developmental Stages ◽

Comparative Transcriptomics ◽

American Cockroach

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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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AKIRIN1: A Potential New Reference Gene in Human Natural Killer Cells and Granulocytes in Sepsis

International Journal of Molecular Sciences ◽

10.3390/ijms20092290 ◽

2019 ◽

Vol 20 (9) ◽

pp. 2290 ◽

Cited By ~ 2

Author(s):

Anna Coulibaly ◽

Sonia Y. Velásquez ◽

Carsten Sticht ◽

Ana Sofia Figueiredo ◽

Bianca S. Himmelhan ◽

...

Keyword(s):

Nk Cells ◽

Natural Killer ◽

Reference Gene ◽

Reference Genes ◽

Inflammatory Diseases ◽

Transcriptional Profiling ◽

Lps Challenge ◽

Human Natural Killer Cells ◽

Suitable Reference

Timely and reliable distinction of sepsis from non-infectious systemic inflammatory response syndrome (SIRS) supports adequate antimicrobial therapy and saves lives but is clinically challenging. Blood transcriptional profiling promises to deliver insights into the pathomechanisms of SIRS and sepsis and to accelerate the discovery of urgently sought sepsis biomarkers. However, suitable reference genes for normalizing gene expression in these disease conditions are lacking. In addition, variability in blood leukocyte subtype composition complicates gene profile interpretation. Here, we aimed to identify potential reference genes in natural killer (NK) cells and granulocytes from patients with SIRS and sepsis on intensive care unit (ICU) admission. Discovery by a two-step probabilistic selection from microarray data followed by validation through branched DNA assays in independent patients revealed several candidate reference genes in NK cells including AKIRIN1, PPP6R3, TAX1BP1, and ADRBK1. Initially, no candidate genes could be validated in patient granulocytes. However, we determined highly similar AKIRIN1 expression also in SIRS and sepsis granulocytes and no change by in vitro LPS challenge in granulocytes from healthy donors. Inspection of external neutrophil transcriptome datasets further support unchanged AKIRIN1 expression in human systemic inflammation. As a potential new reference gene in NK cells and granulocytes in infectious and inflammatory diseases, AKIRIN1 may improve our pathomechanistic understanding of SIRS and sepsis and help identifying new sepsis biomarkers.

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