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Zhang H, Li X, Bai J, Zhang C. Mice with NOP2/sun RNA methyltransferase 5 deficiency die before reaching puberty due to fatal kidney damage. Ren Fail 2024; 46:2349139. [PMID: 38712768 PMCID: PMC11078075 DOI: 10.1080/0886022x.2024.2349139] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2023] [Accepted: 04/25/2024] [Indexed: 05/08/2024] Open
Abstract
BACKGROUND NOP2/Sun RNA methyltransferase 5 (NSUN5) is an RNA methyltransferase that has a broad distribution and plays critical roles in various biological processes. However, our knowledge of the biological functions of NSUN5 in mammals is very limited. Therefore, in this study, we investigate the role of NSUN5 in mice. METHODS In the present research, we built a mouse model (Nsun5-/-) using the CRISPR/Cas9 system to investigated the specific role of NSUN5. RESULTS We observed that Nsun5-/- mice had a reduced body weight compared to wild-type mice. Additionally, their survival rate gradually decreased to 20% after postnatal day (PD) 21. Further examination revealed the Nsun5-/- mice had multiple organ damage, with the most severe damage occurring in the kidneys. Moreover, we observed glycogen deposition and fibrosis, along with a notable shorting of the primary foot processes of glomeruli in Nsun5-/- kidneys. Furthermore, we found that the kidneys of Nsun5-/- mice showed increased expression of the apoptotic signal Caspase-3 and accumulated stronger DNA damage at PD 21. CONCLUSIONS In our study, we found that mice lacking NSUN5 died before puberty due to kidney fatal damage caused by DNA damage and cell apoptosis. These results suggest that NSUN5 plays a vital role in preventing the accumulation of DNA damage and cell apoptosis in the kidney.
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Affiliation(s)
- Hongya Zhang
- Shandong Provincial Key Laboratory of Animal Resistance Biology, College of Life Sciences, Shandong Normal University, Jinan, Shandong, China
| | - Xiaohui Li
- Shandong Provincial Key Laboratory of Animal Resistance Biology, College of Life Sciences, Shandong Normal University, Jinan, Shandong, China
| | - Jing Bai
- Jinan Maternal and Child Health Care Hospital, Shandong First Medical University, Jinan, Shandong, China
| | - Cong Zhang
- Shandong Provincial Key Laboratory of Animal Resistance Biology, College of Life Sciences, Shandong Normal University, Jinan, Shandong, China
- Center for Reproductive Medicine, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
- Shanghai Key Laboratory for Assisted Reproduction and Reproductive Genetics, Shanghai, China
- Shandong Provincial Key Laboratory of Reproductive Medicine, Jinan, Shandong, China
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2
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Naringin Alleviates Glucose-Induced Aging by Reducing Fat Accumulation and Promoting Autophagy in Caenorhabditis elegans. Nutrients 2023; 15:nu15040907. [PMID: 36839265 PMCID: PMC9961211 DOI: 10.3390/nu15040907] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2023] [Revised: 02/07/2023] [Accepted: 02/08/2023] [Indexed: 02/16/2023] Open
Abstract
Naringin (Nar) is a dihydroflavonoid compound, widely found in citrus fruit and used in Chinese herbal medicine. As a phytochemical, it acts as a dietary supplement that can delay aging and prevent aging-related disease, such as obesity and diabetes. However, its exact mechanism remains unclear. In this study, the high-glucose-induced (HGI) Caenorhabditis elegans model was used to evaluate the anti-aging and anti-obesity effects of Nar. The mean lifespan and fast movement span of HGI worms were extended roughly 24% and 11%, respectively, by Nar treatment. Oil red O staining revealed a significant reduction in fat accumulation and dFP::LGG-labeled worms showed the promotion of autophagy. Additionally, whole transcriptome sequencing and gene set variation analysis suggested that Nar upregulated the lipid biosynthesis and metabolism pathways, as well as the TGF-β, Wnt and longevity signaling pathways. Protein-protein interaction (PPI) network analysis identified hub genes in these pathways for further analysis. Mutant worms and RNA interference were used to study mechanisms; the suppression of hlh-30, lgg-1, unc-51, pha-4, skn-1 and yap-1 disabled the fat-lowering, lifespan-prolonging, and health-promoting properties of Nar. Collectively, our findings indicate that Nar plays an important role in alleviating HGI-aging and anti-obesity effects by reducing fat accumulation and promoting autophagy.
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Zhou R, Fan M, Zhao M, Jiang X, Liu Q. Overexpression of LtKNOX1 from Lilium tsingtauense in Nicotiana benthamiana affects the development of leaf morphology. PLANT SIGNALING & BEHAVIOR 2022; 17:2031783. [PMID: 35139775 PMCID: PMC9176240 DOI: 10.1080/15592324.2022.2031783] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/21/2021] [Revised: 01/18/2022] [Accepted: 01/18/2022] [Indexed: 05/27/2023]
Abstract
Leaves are the main vegetative organs of the aboveground part of plants and play an important role in plant morphogenesis. KNOTTED-LIKE HOMEOBOX (KNOX) plays a crucial role in regulating leaf cell fate and maintaining leaf development. In this study, we analyzed LtKNOX1 from Lilium tsingtauense and illustrated its function in transgenic plants. Tissue-specific expression analysis indicated that LtKNOX1 was highly expressed in stems, young flower buds, and shoot apical meristems (SAMs). Ectopic overexpression of LtKNOX1 in Nicotiana benthamiana suggested that transformants with mild phenotypes were characterized by foliar wrinkles and mildly curled leaves; transformants with intermediate phenotypes showed severely crimped blades and narrow leaf angles, and the most severe phenotypes lacked normal SAMs and leaves. Moreover, the expression levels of genes involved in the regulation of KNOX in transgenic plants were detected, including ASYMMETRIC LEAVES1, PIN-FORMED 1, GA20-oxidase, CUP-SHAPED COTYLEDON 2, CLAVATA 1 and WUSCHEL(WUS), and the expression of other genes were down-regulated except WUS. This study contributes to our understanding of the LtKNOX1 function.
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Affiliation(s)
- Rui Zhou
- College of Landscape Architecture and Forestry, Qingdao Agricultural University, Qingdao, Shandong, China
| | - Menglong Fan
- State Key Laboratory of Tree Genetics and Breeding, Research Institute of Subtropical Forestry, Chinese Academy of Forestry, Hangzhou, Zhejiang, China
| | - Mei Zhao
- College of Landscape Architecture and Forestry, Qingdao Agricultural University, Qingdao, Shandong, China
| | - Xinqiang Jiang
- College of Landscape Architecture and Forestry, Qingdao Agricultural University, Qingdao, Shandong, China
| | - Qinghua Liu
- College of Landscape Architecture and Forestry, Qingdao Agricultural University, Qingdao, Shandong, China
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4
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Analysis of Pathogenic Vibrio Contamination in Marine Products along China Based on Fluorescence Quantitative PCR. J FOOD QUALITY 2022. [DOI: 10.1155/2022/9572064] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
At present, aquatic product pollution has become the main root of frequent food safety problems and causes economic losses. Vibrio is one of the main pathogens causing foodborne diseases. In this study, in order to uncover the pollution status of pathogenic Vibrio in the marine products of China, a total of 646 aquatic products were collected and analyzed from 10 coastal cities in China. Five kinds of pathogenic Vibrio were separated from these samples and monitored to explore the relationship between pollution and the pathogen. Real-time fluorescence quantitative PCR was adopted to detect foodborne Vibrio quantitatively in marine aquatic products. Aquatic pathogenic Vibrio was collected in different regions, different types of aquatic products, and different sampling places, and the difference in detection rate was statistically significant through statistical analysis. This study made a frame for the pollution degree of pathogenic Vibrio in marine products in China and established the dominant flora of pathogenic Vibrio in different types of aquatic products, which provides a theoretical basis for food safety supervision departments to take targeted prevention and control measures.
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Shaheen N, Akhtar J, Umer Z, Khan MHF, Bakhtiari MH, Saleem M, Faisal A, Tariq M. Polycomb Requires Chaperonin Containing TCP-1 Subunit 7 for Maintaining Gene Silencing in Drosophila. Front Cell Dev Biol 2021; 9:727972. [PMID: 34660585 PMCID: PMC8517254 DOI: 10.3389/fcell.2021.727972] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2021] [Accepted: 08/30/2021] [Indexed: 11/13/2022] Open
Abstract
In metazoans, heritable states of cell type-specific gene expression patterns linked with specialization of various cell types constitute transcriptional cellular memory. Evolutionarily conserved Polycomb group (PcG) and trithorax group (trxG) proteins contribute to the transcriptional cellular memory by maintaining heritable patterns of repressed and active expression states, respectively. Although chromatin structure and modifications appear to play a fundamental role in maintenance of repression by PcG, the precise targeting mechanism and the specificity factors that bind PcG complexes to defined regions in chromosomes remain elusive. Here, we report a serendipitous discovery that uncovers an interplay between Polycomb (Pc) and chaperonin containing T-complex protein 1 (TCP-1) subunit 7 (CCT7) of TCP-1 ring complex (TRiC) chaperonin in Drosophila. CCT7 interacts with Pc at chromatin to maintain repressed states of homeotic and non-homeotic targets of PcG, which supports a strong genetic interaction observed between Pc and CCT7 mutants. Depletion of CCT7 results in dissociation of Pc from chromatin and redistribution of an abundant amount of Pc in cytoplasm. We propose that CCT7 is an important modulator of Pc, which helps Pc recruitment at chromatin, and compromising CCT7 can directly influence an evolutionary conserved epigenetic network that supervises the appropriate cellular identities during development and homeostasis of an organism.
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Affiliation(s)
- Najma Shaheen
- Epigenetics and Gene Regulation Laboratory, Department of Biology, Syed Babar Ali School of Science and Engineering, Lahore University of Management Sciences, Lahore, Pakistan
| | - Jawad Akhtar
- Epigenetics and Gene Regulation Laboratory, Department of Biology, Syed Babar Ali School of Science and Engineering, Lahore University of Management Sciences, Lahore, Pakistan
| | - Zain Umer
- Epigenetics and Gene Regulation Laboratory, Department of Biology, Syed Babar Ali School of Science and Engineering, Lahore University of Management Sciences, Lahore, Pakistan
| | - Muhammad Haider Farooq Khan
- Epigenetics and Gene Regulation Laboratory, Department of Biology, Syed Babar Ali School of Science and Engineering, Lahore University of Management Sciences, Lahore, Pakistan
| | - Mahnoor Hussain Bakhtiari
- Epigenetics and Gene Regulation Laboratory, Department of Biology, Syed Babar Ali School of Science and Engineering, Lahore University of Management Sciences, Lahore, Pakistan
| | - Murtaza Saleem
- Department of Physics, Syed Babar Ali School of Science and Engineering, Lahore University of Management Sciences, Lahore, Pakistan
| | - Amir Faisal
- Cancer Therapeutics Laboratory, Department of Biology, Syed Babar Ali School of Science and Engineering, Lahore University of Management Sciences, Lahore, Pakistan
| | - Muhammad Tariq
- Epigenetics and Gene Regulation Laboratory, Department of Biology, Syed Babar Ali School of Science and Engineering, Lahore University of Management Sciences, Lahore, Pakistan
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N1, N12-Diacetylspermine Is Elevated in Colorectal Cancer and Promotes Proliferation through the miR-559/CBS Axis in Cancer Cell Lines. JOURNAL OF ONCOLOGY 2021; 2021:6665704. [PMID: 34603448 PMCID: PMC8486517 DOI: 10.1155/2021/6665704] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/11/2020] [Revised: 08/06/2021] [Accepted: 08/15/2021] [Indexed: 01/05/2023]
Abstract
N1, N12-Diacetylspermine (DiAcSpm) has been reported to be upregulated in the urine of cancer patients. Mass spectrometry has shown elevated DiAcSpm expressions in colorectal cancer (CRC) tissues. However, the diagnostic application of DiAcSpm is not available due to a lack of diagnostic grade antibodies. Also, its biological roles in CRC cells remain unexplored. In the present study, we developed an antibody that directly detected DiAcSpm expression in paraffin-embedded tissues. We also characterized its biological characteristics and underlying mechanisms. Polyclonal antibodies were generated by immunizing animals with a synthetic product of DiAcSpm. Antibody DAS AB016 showed strong sensitivity against DiAcSpm in CRC tissues. Immunohistochemistry results showed that DiAcSpm expression was significantly elevated in CRC tissues. High levels of DiAcSpm correlated with the clinical stage and Ki67 index. DiAcSpm treatment increased levels of proliferation, cell cycle progression, and cyclin D1 and cyclin E proteins in CRC cell lines, SW480 and Caco-2. DiAcSpm also upregulated ATP production in these two cell lines. RNA-sequencing showed that DiAcSpm downregulated miR-559, which was confirmed using RT-qPCR. The luciferase reporter assay, western blotting, and RT-qPCR showed that cystathionine β-synthase (CBS) was the target of miR-559. miR-559 inhibited, while CBS accelerated, CRC proliferation. In addition, CBS siRNA knockdown blocked the biological effects of DiAcSpm on CRC cells. In conclusion, DiAcSpm was found to be increased in CRC tissues using a newly developed antibody. DiAcSpm accelerated CRC proliferation by regulating the miR-559/CBS axis.
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7
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Fan X, Yao H, Liu X, Shi Q, Lv L, Li P, Wang R, Tang T, Qi K. High-Fat Diet Alters the Expression of Reference Genes in Male Mice. Front Nutr 2020; 7:589771. [PMID: 33330591 PMCID: PMC7732482 DOI: 10.3389/fnut.2020.589771] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Accepted: 10/19/2020] [Indexed: 12/17/2022] Open
Abstract
Quantitative PCR (qPCR), the most accurate and sensitive technique for quantifying mRNA expression, and choice of appropriate reference genes for internal error controlling in qPCR are essential to understanding the molecular mechanisms that drive the obesity epidemic and its comorbidities. In this study, using the high-fat diet (HFD)-induced obese mouse model, we assessed the expression of 10 commonly used reference genes to validate gene-expression stability in adipose tissue, liver, and muscle across different time points (4, 8, 12, and 16 weeks after HFD feeding) during the process of obesity. The data were analyzed by the GeNorm, NormFinder, BestKeeper, and Delta-Ct method, and the results showed that the most stable reference genes were different for a specific organ or tissue in a specific time point; however, PPIA, RPLP0, and YWHAZ were the top three most stable reference genes in qPCR experiments on adipose, hepatic tissues, and muscles of mice in diet-induced obesity. In addition, the mostly used genes ACTB and GAPDH were more unstable in the fat and liver, the ACTB mRNA levels were increased in four adipose tissues, and the GAPDH mRNA levels were decreased in four adipose tissues and liver after HFD feeding. These results suggest that PPIA, RPLP0, or YWHAZ may be more appropriate to be used as reference gene than ACTB and GAPDH in the adipose tissue and liver of mice during the process of high-fat diet-induced obesity.
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Affiliation(s)
- Xiuqin Fan
- Laboratory of Nutrition and Development, Beijing Pediatric Research Institute, Beijing Children's Hospital, Capital Medical University, National Center for Children's Health, Beijing, China
| | - Hongyang Yao
- Laboratory of Nutrition and Development, Beijing Pediatric Research Institute, Beijing Children's Hospital, Capital Medical University, National Center for Children's Health, Beijing, China
| | - Xuanyi Liu
- Laboratory of Nutrition and Development, Beijing Pediatric Research Institute, Beijing Children's Hospital, Capital Medical University, National Center for Children's Health, Beijing, China
| | - Qiaoyu Shi
- Laboratory of Nutrition and Development, Beijing Pediatric Research Institute, Beijing Children's Hospital, Capital Medical University, National Center for Children's Health, Beijing, China
| | | | - Ping Li
- Laboratory of Nutrition and Development, Beijing Pediatric Research Institute, Beijing Children's Hospital, Capital Medical University, National Center for Children's Health, Beijing, China
| | - Rui Wang
- Laboratory of Nutrition and Development, Beijing Pediatric Research Institute, Beijing Children's Hospital, Capital Medical University, National Center for Children's Health, Beijing, China
| | - Tiantian Tang
- Laboratory of Nutrition and Development, Beijing Pediatric Research Institute, Beijing Children's Hospital, Capital Medical University, National Center for Children's Health, Beijing, China
| | - Kemin Qi
- Laboratory of Nutrition and Development, Beijing Pediatric Research Institute, Beijing Children's Hospital, Capital Medical University, National Center for Children's Health, Beijing, China
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8
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Wylezinski LS, Shaginurova GI, Spurlock Iii CF. Longitudinal assessment and stability of long non-coding RNA gene expression profiles measured in human peripheral whole blood collected into PAXgene blood RNA tubes. BMC Res Notes 2020; 13:531. [PMID: 33183338 PMCID: PMC7664084 DOI: 10.1186/s13104-020-05360-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2020] [Accepted: 10/26/2020] [Indexed: 12/18/2022] Open
Abstract
Objective Long non-coding RNAs (lncRNAs) are emerging as novel biomarkers for a variety of chronic conditions including autoimmune disease. PAXgene Blood RNA tubes are routinely used in clinical research and molecular diagnostic development to capture RNA profiles in peripheral whole blood. While the stability of mRNA expression profiles captured using PAXgene tubes has been documented previously, no previous work has determined the stability of lncRNA expression profiles observed in PAXgene tubes stored at − 80 °C. Here we sought to determine the effects on lncRNA expression profiles following − 80 °C storage of total RNA templates, cDNA synthesized using fresh or frozen total RNA template, and the impact of freeze–thaw cycles on both total RNA and cDNA obtained from PAXgene tubes. Results We find that storage of whole blood in PAXgene tubes, total RNA and cDNA for up to 1 year at − 80 °C or up to ten total RNA or cDNA freeze–thaw cycles do not significantly alter lncRNA expression profiles compared to baseline. As monthly expression profiles were determined, some month to month lncRNA expression variability was observed. However, all monthly observations fell within the 95% confidence interval calculated at baseline.
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Affiliation(s)
- Lukasz S Wylezinski
- IQuity, Inc, 111, 10th Avenue South, Suite 100, Nashville, TN, 37203, USA.,Decode Health, Inc, 209 10th Avenue South, Suite 404, Nashville, TN, USA.,Department of Medicine, Vanderbilt University School of Medicine, 1161 21st Avenue South, Medical Center North T3113, Nashville, TN, USA
| | | | - Charles F Spurlock Iii
- IQuity, Inc, 111, 10th Avenue South, Suite 100, Nashville, TN, 37203, USA. .,Decode Health, Inc, 209 10th Avenue South, Suite 404, Nashville, TN, USA. .,Department of Medicine, Vanderbilt University School of Medicine, 1161 21st Avenue South, Medical Center North T3113, Nashville, TN, USA.
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Effect of PDGF-B Gene-Activated Acellular Matrix and Mesenchymal Stem Cell Transplantation on Full Thickness Skin Burn Wound in Rat Model. Tissue Eng Regen Med 2020; 18:235-251. [PMID: 33145744 DOI: 10.1007/s13770-020-00302-3] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2020] [Revised: 08/10/2020] [Accepted: 09/16/2020] [Indexed: 10/23/2022] Open
Abstract
BACKGROUND Full thickness burn wounds are lack of angiogenesis, cell migration, epithelialisation and finally scar tissue formation. Tissue engineered composite graft can provide sustained release of growth factor and promote the wound healing by cell migration, early angiogenesis and proliferation of extracellular matrix and wound remodeling. The objective of this study was to evaluate the gene embedded (pDNA-platelet-derived growth factor, PDGF-B) porcine acellular urinary bladder matrix with transfected mesenchymal stem cells (rBMSC) on healing of full thickness burn wound in rat model. METHODS Full thickness burn wound of 2 × 2 cm size was created in dorsum of rat model under general anesthesia. Burn wounds were treated with silver sulfadiazine; porcine acellular urinary bladder matrix (PAUBM); PAUBM transfected with pDNA-PDGF-B; PAUBM seeded with rBMSC; PAUBM seeded with rBMSC transfected with pDNA-PDGF-B in groups A, B, C, D and E respectively. The wound healing was assessed based on clinical, macroscopically, immunologically, histopathological and RT-qPCR parameters. RESULTS Wound was significantly healed in group E and group D with early extracellular matrix deposition, enhanced granulation tissue formation and early angiogenesis compared to all other groups. The immunologic response against porcine acellular matrix showed that PDGF-B gene activated matrix along with stem cell group showed less antibody titer against acellular matrix than other groups in all intervals. PDGF gene activated matrix releasing the PDGF-B and promote the healing of full thickness burn wound with neovascularization and neo tissue formation. PDGF gene also enhances secretion of other growth factors results in PDGF mediated regenerative activities. This was confirmed in RT-qPCR at various time intervals. CONCLUSION Gene activated matrix encoded for PDGF-B protein transfected stem cells have been clinically proven for early acceleration of angiogenesis and tissue regeneration in burn wounds in rat models. Evaluation of PDGF-B gene-activated acellular matrix and mesenchymal stem cell in full thickness skin burn wound in rat.
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10
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Hampton TH, Koeppen K, Bashor L, Stanton BA. Selection of reference genes for quantitative PCR: identifying reference genes for airway epithelial cells exposed to Pseudomonas aeruginosa. Am J Physiol Lung Cell Mol Physiol 2020; 319:L256-L265. [PMID: 32521165 PMCID: PMC7473940 DOI: 10.1152/ajplung.00158.2020] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2020] [Revised: 06/08/2020] [Accepted: 06/09/2020] [Indexed: 12/30/2022] Open
Abstract
Most quantitative PCR (qPCR) experiments report differential expression relative to the expression of one or more reference genes. Therefore, when experimental conditions alter reference gene expression, qPCR results may be compromised. Little is known about the magnitude of this problem in practice. We found that reference gene responses are common and hard to predict and that their stability should be demonstrated in each experiment. Our reanalysis of 15 airway epithelia microarray data sets retrieved from the National Center for Biotechnology Information (NCBI) identified no common reference gene that was reliable in all 15 studies. Reanalysis of published RNA sequencing (RNA-seq) data in which human bronchial epithelial cells (HBEC) were exposed to Pseudomonas aeruginosa revealed that minor experimental details, including bacterial strain, may alter reference gene responses. Direct measurement of 32 TaqMan reference genes in primary cultures of HBEC exposed to P. aeruginosa (strain PA14) demonstrated that choosing an unstable reference gene could make it impossible to observe statistically significant changes in IL8 gene expression. We found that reference gene instability is a general phenomenon and not limited to studies of airway epithelial cells. In a diverse compendium of 986 human microarray experiments retrieved from the NCBI, reference genes were differentially expressed in 42% of studies. Experimentally induced changes in reference gene expression ranged from 21% to 212%. These results highlight the importance of identifying adequate reference genes for each experimental system and documenting their response to treatment in each experiment. This will enhance experimental rigor and reproducibility in qPCR studies.
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Affiliation(s)
- Thomas H Hampton
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire
| | - Katja Koeppen
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire
| | - Laura Bashor
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire
| | - Bruce A Stanton
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire
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11
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Green MR, Sambrook J. Polymerase Chain Reaction. Cold Spring Harb Protoc 2019; 2019:2019/6/pdb.top095109. [PMID: 31160389 DOI: 10.1101/pdb.top095109] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
The polymerase chain reaction (PCR) underlies almost all of modern molecular cloning. Using PCR, a defined target sequence that occurs once within a DNA of high complexity and large size-an entire mammalian genome, for example-can be rapidly and selectively amplified in a quasi-exponential chain reaction that generates millions of copies. The reaction is simple to set up, cheap, and undemanding, the only requirement being some knowledge of the nucleotide sequences of the target. In addition to its simplicity, PCR is robust, speedy, flexible, and sensitive.
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Green MR, Sambrook J. Quantification of DNA by Real-Time Polymerase Chain Reaction (PCR). Cold Spring Harb Protoc 2018; 2018:2018/10/pdb.prot095034. [PMID: 30275076 DOI: 10.1101/pdb.prot095034] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
There are few differences between the experimental steps necessary for amplifying template DNA in a real-time thermocycler and a standard polymerase chain reaction (PCR). In real-time PCR, it is necessary, however, to optimize the concentration of primers and probe and to perform a standard curve. It is also important to consider the data analysis method that will be used.
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Green MR, Sambrook J. Quantification of RNA by Real-Time Reverse Transcription-Polymerase Chain Reaction (RT-PCR). Cold Spring Harb Protoc 2018; 2018:2018/10/pdb.prot095042. [PMID: 30275077 DOI: 10.1101/pdb.prot095042] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
This protocol describes a real-time reverse transcription-polymerase chain reaction (RT-PCR) assay using a two-enzyme, two-tube approach, carried out using either SYBR Green I or TaqMan chemistries. The protocol uses a PCR volume of 20 µL (although most manufacturers recommend 50-µL reactions). However, if the PCR target is not very abundant (i.e., present at one to 10 copies per sample), a larger volume may yield better reproducibility between samples. Discussion on preparing high-quality RNA, choosing a priming method, selecting an enzyme, and selecting an endogenous reference gene is also included.
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Green MR, Sambrook J. Optimizing Primer and Probe Concentrations for Use in Real-Time Polymerase Chain Reaction (PCR) Assays. Cold Spring Harb Protoc 2018; 2018:2018/10/pdb.prot095018. [PMID: 30275074 DOI: 10.1101/pdb.prot095018] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Once primers and probes have been designed and obtained, it is necessary to optimize their concentration for each real-time polymerase chain reaction (PCR) assay. A set of PCRs is assembled in which the concentrations of forward and reverse primers are varied independently. Following amplification of the template DNA, amplification plots are compared. A standard curve is generated to determine the efficiency, sensitivity, and reproducibility of the assay. If SYBR Green I is used as the probe, then the melting curves are also analyzed.
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Green MR, Sambrook J. Constructing a Standard Curve for Real-Time Polymerase Chain Reaction (PCR) Experiments. Cold Spring Harb Protoc 2018; 2018:2018/10/pdb.prot095026. [PMID: 30275075 DOI: 10.1101/pdb.prot095026] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
It is essential to prepare a standard curve for every real-time polymerase chain reaction (PCR) experiment. This protocol is used to construct a standard curve in which the template concentration is unknown. Such a standard curve is suitable for optimization experiments and for performing relative quantification by the standard curve method. To construct a standard curve for absolute quantification, the same principles apply as those presented here, but the concentration of the standards must be determined by an independent method.
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