1
|
Nevone A, Lattarulo F, Russo M, Panno G, Milani P, Basset M, Avanzini MA, Merlini G, Palladini G, Nuvolone M. A Strategy for the Selection of RT-qPCR Reference Genes Based on Publicly Available Transcriptomic Datasets. Biomedicines 2023; 11:biomedicines11041079. [PMID: 37189697 DOI: 10.3390/biomedicines11041079] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2023] [Revised: 03/23/2023] [Accepted: 03/27/2023] [Indexed: 04/05/2023] Open
Abstract
In the next-generation sequencing era, RT-qPCR is still widely employed to quantify levels of nucleic acids of interest due to its popularity, versatility, and limited costs. The measurement of transcriptional levels through RT-qPCR critically depends on reference genes used for normalization. Here, we devised a strategy to select appropriate reference genes for a specific clinical/experimental setting based on publicly available transcriptomic datasets and a pipeline for RT-qPCR assay design and validation. As a proof-of-principle, we applied this strategy to identify and validate reference genes for transcriptional studies of bone-marrow plasma cells from patients with AL amyloidosis. We performed a systematic review of published literature to compile a list of 163 candidate reference genes for RT-qPCR experiments employing human samples. Next, we interrogated the Gene Expression Omnibus to assess expression levels of these genes in published transcriptomic studies on bone-marrow plasma cells from patients with different plasma cell dyscrasias and identified the most stably expressed genes as candidate normalizing genes. Experimental validation on bone-marrow plasma cells showed the superiority of candidate reference genes identified through this strategy over commonly employed “housekeeping” genes. The strategy presented here may apply to other clinical and experimental settings for which publicly available transcriptomic datasets are available.
Collapse
Affiliation(s)
- Alice Nevone
- Department of Molecular Medicine, University of Pavia, 27100 Pavia, Italy
- Amyloidosis Research and Treatment Center, Fondazione IRCCS Policlinico San Matteo, 27100 Pavia, Italy
| | - Francesca Lattarulo
- Department of Molecular Medicine, University of Pavia, 27100 Pavia, Italy
- Amyloidosis Research and Treatment Center, Fondazione IRCCS Policlinico San Matteo, 27100 Pavia, Italy
| | - Monica Russo
- Department of Molecular Medicine, University of Pavia, 27100 Pavia, Italy
- Amyloidosis Research and Treatment Center, Fondazione IRCCS Policlinico San Matteo, 27100 Pavia, Italy
| | - Giada Panno
- Department of Molecular Medicine, University of Pavia, 27100 Pavia, Italy
- Amyloidosis Research and Treatment Center, Fondazione IRCCS Policlinico San Matteo, 27100 Pavia, Italy
| | - Paolo Milani
- Department of Molecular Medicine, University of Pavia, 27100 Pavia, Italy
- Amyloidosis Research and Treatment Center, Fondazione IRCCS Policlinico San Matteo, 27100 Pavia, Italy
| | - Marco Basset
- Department of Molecular Medicine, University of Pavia, 27100 Pavia, Italy
- Amyloidosis Research and Treatment Center, Fondazione IRCCS Policlinico San Matteo, 27100 Pavia, Italy
| | - Maria Antonietta Avanzini
- Pediatric Hematology Oncology, Cell Factory, Fondazione IRCCS Policlinico San Matteo, 27100 Pavia, Italy
| | - Giampaolo Merlini
- Department of Molecular Medicine, University of Pavia, 27100 Pavia, Italy
- Amyloidosis Research and Treatment Center, Fondazione IRCCS Policlinico San Matteo, 27100 Pavia, Italy
| | - Giovanni Palladini
- Department of Molecular Medicine, University of Pavia, 27100 Pavia, Italy
- Amyloidosis Research and Treatment Center, Fondazione IRCCS Policlinico San Matteo, 27100 Pavia, Italy
| | - Mario Nuvolone
- Department of Molecular Medicine, University of Pavia, 27100 Pavia, Italy
- Amyloidosis Research and Treatment Center, Fondazione IRCCS Policlinico San Matteo, 27100 Pavia, Italy
| |
Collapse
|
2
|
Fragoulis A, Biller K, Fragoulis S, Lex D, Uhlig S, Reiss LK. Reference Gene Selection for Gene Expression Analyses in Mouse Models of Acute Lung Injury. Int J Mol Sci 2021; 22:ijms22157853. [PMID: 34360619 PMCID: PMC8346155 DOI: 10.3390/ijms22157853] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2021] [Revised: 07/12/2021] [Accepted: 07/19/2021] [Indexed: 12/21/2022] Open
Abstract
qRT-PCR still remains the most widely used method for quantifying gene expression levels, although newer technologies such as next generation sequencing are becoming increasingly popular. A critical, yet often underappreciated, problem when analysing qRT-PCR data is the selection of suitable reference genes. This problem is compounded in situations where up to 25% of all genes may change (e.g., due to leukocyte invasion), as is typically the case in ARDS. Here, we examined 11 widely used reference genes for their suitability in commonly used models of acute lung injury (ALI): ventilator-induced lung injury (VILI), in vivo and ex vivo, lipopolysaccharide plus mechanical ventilation (MV), and hydrochloric acid plus MV. The stability of reference gene expression was determined using the NormFinder, BestKeeper, and geNorm algorithms. We then proceeded with the geNorm results because this is the only algorithm that provides the number of reference genes required to achieve normalisation. We chose interleukin-6 (Il-6) and C-X-C motif ligand 1 (Cxcl-1) as the genes of interest to analyse and demonstrate the impact of inappropriate normalisation. Reference gene stability differed between the ALI models and even within the subgroup of VILI models, no common reference gene index (RGI) could be determined. NormFinder, BestKeeper, and geNorm produced slightly different, but comparable results. Inappropriate normalisation of Il-6 and Cxcl1 gene expression resulted in significant misinterpretation in all four ALI settings. In conclusion, choosing an inappropriate normalisation strategy can introduce different kinds of bias such as gain or loss as well as under- or overestimation of effects, affecting the interpretation of gene expression data.
Collapse
Affiliation(s)
- Athanassios Fragoulis
- Department of Anatomy and Cell Biology, Uniklinik RWTH Aachen University, 52074 Aachen, Germany;
| | - Kristina Biller
- Department of Pharmacology and Toxicology, Uniklinik RWTH Aachen University, 52074 Aachen, Germany; (K.B.); (S.F.); (D.L.); (S.U.)
| | - Stephanie Fragoulis
- Department of Pharmacology and Toxicology, Uniklinik RWTH Aachen University, 52074 Aachen, Germany; (K.B.); (S.F.); (D.L.); (S.U.)
| | - Dennis Lex
- Department of Pharmacology and Toxicology, Uniklinik RWTH Aachen University, 52074 Aachen, Germany; (K.B.); (S.F.); (D.L.); (S.U.)
| | - Stefan Uhlig
- Department of Pharmacology and Toxicology, Uniklinik RWTH Aachen University, 52074 Aachen, Germany; (K.B.); (S.F.); (D.L.); (S.U.)
| | - Lucy Kathleen Reiss
- Department of Pharmacology and Toxicology, Uniklinik RWTH Aachen University, 52074 Aachen, Germany; (K.B.); (S.F.); (D.L.); (S.U.)
- Correspondence:
| |
Collapse
|
3
|
Let-7b-5p in vesicles secreted by human airway cells reduces biofilm formation and increases antibiotic sensitivity of P. aeruginosa. Proc Natl Acad Sci U S A 2021; 118:2105370118. [PMID: 34260396 DOI: 10.1073/pnas.2105370118] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Pseudomonas aeruginosa is an opportunistic pathogen that forms antibiotic-resistant biofilms, which facilitate chronic infections in immunocompromised hosts. We have previously shown that P. aeruginosa secretes outer-membrane vesicles that deliver a small RNA to human airway epithelial cells (AECs), in which it suppresses the innate immune response. Here, we demonstrate that interdomain communication through small RNA-containing membrane vesicles is bidirectional and that microRNAs (miRNAs) in extracellular vesicles (EVs) secreted by human AECs regulate protein expression, antibiotic sensitivity, and biofilm formation by P. aeruginosa Specifically, human EVs deliver miRNA let-7b-5p to P. aeruginosa, which systematically decreases the abundance of proteins essential for biofilm formation, including PpkA and ClpV1-3, and increases the ability of beta-lactam antibiotics to reduce biofilm formation by targeting the beta-lactamase AmpC. Let-7b-5p is bioinformatically predicted to target not only PpkA, ClpV1, and AmpC in P. aeruginosa but also the corresponding orthologs in Burkholderia cenocepacia, another notorious opportunistic lung pathogen, suggesting that the ability of let-7b-5p to reduce biofilm formation and increase beta-lactam sensitivity is not limited to P. aeruginosa Here, we provide direct evidence for transfer of miRNAs in EVs secreted by eukaryotic cells to a prokaryote, resulting in subsequent phenotypic alterations in the prokaryote as a result of this interdomain communication. Since let-7-family miRNAs are in clinical trials to reduce inflammation and because chronic P. aeruginosa lung infections are associated with a hyperinflammatory state, treatment with let-7b-5p and a beta-lactam antibiotic in nanoparticles or EVs may benefit patients with antibiotic-resistant P. aeruginosa infections.
Collapse
|
4
|
Liu X, Zhang Y, Huang K, Yin T, Li Q, Zou Q, Guo D, Zhang X. rpoB and efp are stable candidate reference genes for quantitative real-time PCR analysis in Saccharopolyspora spinosa. BIOTECHNOL BIOTEC EQ 2021. [DOI: 10.1080/13102818.2021.1899852] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
Affiliation(s)
- Xiaomeng Liu
- Beijing Key Laboratory of Nutrition & Health and Food Safety, Nutrition and Health Research Institute, COFCO, Beijing, PR China
| | - Yunpeng Zhang
- Beijing Key Laboratory of Nutrition & Health and Food Safety, Nutrition and Health Research Institute, COFCO, Beijing, PR China
| | - Kexue Huang
- Qilu Pharmaceutical (Inner Mongolia) Co., Ltd, Hohhot, Inner Mongolia, PR China
| | - Tie Yin
- Beijing Key Laboratory of Nutrition & Health and Food Safety, Nutrition and Health Research Institute, COFCO, Beijing, PR China
| | - Qi Li
- Beijing Key Laboratory of Nutrition & Health and Food Safety, Nutrition and Health Research Institute, COFCO, Beijing, PR China
| | - Qiulong Zou
- Beijing Key Laboratory of Nutrition & Health and Food Safety, Nutrition and Health Research Institute, COFCO, Beijing, PR China
| | - Dongsheng Guo
- School of Food Science and Pharmaceutical Engineering, Nanjing Normal University, Nanjing, Jiangsu Province, PR China
| | - Xiaolin Zhang
- Beijing Key Laboratory of Nutrition & Health and Food Safety, Nutrition and Health Research Institute, COFCO, Beijing, PR China
- School of Food Science and Pharmaceutical Engineering, Nanjing Normal University, Nanjing, Jiangsu Province, PR China
| |
Collapse
|