Applications like drug development need simple and streamlined methods to process samples from 96-well cell culture plates for gene expression measurements. Unfortunately, current options are expensive for such processing. Therefore, our aim was to develop a method that would allow streamlined analysis of mRNA from 96-well cell culture plates while being relatively cheap and simple. We developed a method based on the qPCR 'Cells-to-cDNA' approach and validated it against commercially available kits using the same approach or spin columns-based RNA purification. For this purpose, we conducted a series of comparisons of gene expression from peripheral blood mononuclear cells, SK-HEP-1 and U-87 cell cultures in 96-well plates. Our final method involved lysing cells with 25-100 µl solution of 0.5% SDS, 10 mM DTT, 1 mg ml-1 proteinase K dissolved in water, 1 h incubation at 50°C, followed by proteinase K inactivation at 90°C for 5 min and lysate neutralization with 1 : 1 dilution by 20% Tween 20 solution. Reverse transcription and qPCR were carried out using standard methods. This method showed a mean reduction of Ct ± s.d. value by 2.4 ± 1.3 compared with the 'Cells-to-cDNA' kit and by 1.4 ± 0.5 compared with the RNA purification kit with lower variability.

• Klíčová slova
• RNA isolation, cell lysis, in vitro, mRNA, peripheral blood mononuclear cells, proteinase k, qPCR,
• MeSH
• analýza nákladů a výnosů MeSH
• buněčné kultury * metody   MeSH
• komplementární DNA * genetika   biosyntéza   MeSH
• kvantitativní polymerázová řetězová reakce metody   MeSH
• leukocyty mononukleární metabolismus   MeSH
• lidé MeSH
• messenger RNA genetika   MeSH
• stanovení celkové genové exprese metody   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• komplementární DNA * MeSH
• messenger RNA MeSH

Reverse transcription quantitative PCR (RT-qPCR) has delivered significant insights in understanding the gene expression landscape. Thanks to its precision, sensitivity, flexibility, and cost effectiveness, RT-qPCR has also found utility in advanced single-cell analysis. Single-cell RT-qPCR now represents a well-established method, suitable for an efficient screening prior to single-cell RNA sequencing (scRNA-Seq) experiments, or, oppositely, for validation of hypotheses formulated from high-throughput approaches. Here, we aim to provide a comprehensive summary of the scRT-qPCR method by discussing the limitations of single-cell collection methods, describing the importance of reverse transcription, providing recommendations for the preamplification and primer design, and summarizing essential data processing steps. With the detailed protocol attached in the appendix, this tutorial provides a set of guidelines that allow any researcher to perform scRT-qPCR measurements of the highest standard.

• Klíčová slova
• RT-qPCR, gene expression, preamplification, quantitative PCR, reverse transcription, sample collection, single cell,
• MeSH
• analýza jednotlivých buněk metody   normy   MeSH
• kvantitativní polymerázová řetězová reakce metody   normy   MeSH
• lidé MeSH
• reverzní transkripce genetika   MeSH
• senzitivita a specificita MeSH
• stanovení celkové genové exprese metody   normy   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• přehledy MeSH

Analyzing rare DNA and RNA molecules in limited sample sizes, such as liquid biopsies and single cells, often requires preamplification, which makes downstream analyses particularly sensitive to polymerase chain reaction (PCR) generated contamination. Herein, we assessed the feasibility of performing Cod uracil-DNA N-glycosylase (Cod UNG) treatment in combination with targeted preamplification, using deoxyuridine triphosphate (dUTP) to eliminate carry-over DNA. Cod UNG can be completely and irreversibly heat inactivated, a prerequisite in preamplification methods, where any loss of amplicons is detrimental to subsequent quantification. Using 96 target assays and quantitative real-time PCR, we show that replacement of deoxythymidine triphosphate (dTTP) with dUTP in the preamplification reaction mix results in comparable dynamic range, reproducibility, and sensitivity. Moreover, Cod UNG essentially removes all uracil-containing template of most assays, regardless of initial concentration, without affecting downstream analyses. Finally, we demonstrate that the use of Cod UNG and dUTP in targeted preamplification can easily be included in the workflow for single-cell gene expression profiling. In summary, Cod UNG treatment in combination with targeted preamplification using dUTP provides a simple and efficient solution to eliminate carry-over contamination and the generation of false positives and inaccurate quantification.

• Klíčová slova
• Cod UNG, contamination, dUTP, preamplification, qPCR, single-cell analysis,
• MeSH
• analýza jednotlivých buněk MeSH
• deoxyuracilnukleotidy metabolismus   MeSH
• Gadus morhua metabolismus   MeSH
• kontaminace DNA * MeSH
• reprodukovatelnost výsledků MeSH
• stanovení celkové genové exprese MeSH
• uracil-DNA-glykosidasa metabolismus   MeSH
• uracil metabolismus   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• deoxyuracilnukleotidy MeSH
• deoxyuridine triphosphate MeSH Prohlížeč
• uracil-DNA-glykosidasa MeSH
• uracil MeSH

FUS-DDIT3 belongs to the FET (FUS, EWSR1, and TAF15) family of fusion oncogenes, which collectively are considered to be key players in tumor development. Even though over 90% of all myxoid liposarcomas (MLS) have a FUS-DDIT3 gene fusion, there is limited understanding of the signaling pathways that regulate its expression. In order to study cell proliferation and FUS-DDIT3 regulation at mRNA and protein levels, we first developed a direct cell lysis approach that allows DNA, mRNA, and protein to be analyzed in the same sample using quantitative PCR, reverse transcription quantitative qPCR and proximity ligation assay, respectively. We screened 70 well-characterized kinase inhibitors and determined their effects on cell proliferation and expression of FUS-DDIT3 and FUS at both mRNA and protein levels in the MLS 402-91 cell line, where twelve selected inhibitors were evaluated further in two additional MLS cell lines. Both FUS-DDIT3 and FUS mRNA expression correlated with cell proliferation and both transcripts were co-regulated in most conditions, indicating that the common 5' FUS promotor is important in transcriptional regulation. In contrast, FUS-DDIT3 and FUS protein levels displayed more cell line dependent expression. Furthermore, most JAK inhibitors caused FUS-DDIT3 downregulation at both mRNA and protein levels. In conclusion, defining factors that regulate FUS-DDIT3 expression opens new means to understand MLS development at the molecular level.

• MeSH
• DNA analýza   genetika   metabolismus   MeSH
• fúzní onkogenní proteiny analýza   genetika   metabolismus   MeSH
• lidé MeSH
• messenger RNA analýza   genetika   metabolismus   MeSH
• myxoidní liposarkom genetika   metabolismus   MeSH
• nádorové buněčné linie MeSH
• proliferace buněk účinky léků   MeSH
• protinádorové látky farmakologie   MeSH
• regulace genové exprese u nádorů účinky léků   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• DNA MeSH
• FUS-DDIT3 fusion protein, human MeSH Prohlížeč
• fúzní onkogenní proteiny MeSH
• messenger RNA MeSH
• protinádorové látky MeSH

Single-cell analysis has become an established method to study cell heterogeneity and for rare cell characterization. Despite the high cost and technical constraints, applications are increasing every year in all fields of biology. Following the trend, there is a tremendous development of tools for single-cell analysis, especially in the RNA sequencing field. Every improvement increases sensitivity and throughput. Collecting a large amount of data also stimulates the development of new approaches for bioinformatic analysis and interpretation. However, the essential requirement for any analysis is the collection of single cells of high quality. The single-cell isolation must be fast, effective, and gentle to maintain the native expression profiles. Classical methods for single-cell isolation are micromanipulation, microdissection, and fluorescence-activated cell sorting (FACS). In the last decade several new and highly efficient approaches have been developed, which not just supplement but may fully replace the traditional ones. These new techniques are based on microfluidic chips, droplets, micro-well plates, and automatic collection of cells using capillaries, magnets, an electric field, or a punching probe. In this review we summarize the current methods and developments in this field. We discuss the advantages of the different commercially available platforms and their applicability, and also provide remarks on future developments.

• Klíčová slova
• analysis, collection, isolation, single cell,
• MeSH
• analýza jednotlivých buněk přístrojové vybavení   metody   MeSH
• lidé MeSH
• mikrofluidika přístrojové vybavení   metody   MeSH
• průtoková cytometrie přístrojové vybavení   metody   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH

Reverse transcription quantitative PCR (RT-qPCR) is already an established tool for mRNA detection and quantification. Since recently, this technique has been successfully employed for gene expression analyses, and also in individual cells (single cell RT-qPCR). Although the advantages of single cell measurements have been proven several times, a study correlating the expression measured on single cells, and in bulk samples consisting of a large number of cells, has been missing. Here, we collected a large data set to explore the relation between gene expression measured in single cells and in bulk samples, reflected by qPCR Cq values. We measured the expression of 95 genes in 12 bulk samples, each containing thousands of astrocytes, and also in 693 individual astrocytes. Combining the data, we described the relation between Cq values measured in bulk samples with either the percentage of the single cells that express the given genes, or the average expression of the genes across the single cells. We show that data obtained with single cell RT-qPCR are fully consistent with measurements in bulk samples. Our results further provide a base for quality control in single cell expression profiling, and bring new insights into the biological process of cellular expression.

• MeSH
• analýza jednotlivých buněk * MeSH
• gliový fibrilární kyselý protein genetika   MeSH
• messenger RNA genetika   MeSH
• myši transgenní MeSH
• myši MeSH
• polymerázová řetězová reakce s reverzní transkripcí MeSH
• stanovení celkové genové exprese * MeSH
• zelené fluorescenční proteiny genetika   MeSH
• zvířata MeSH
• Check Tag
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• enhanced green fluorescent protein MeSH Prohlížeč
• gliový fibrilární kyselý protein MeSH
• messenger RNA MeSH
• zelené fluorescenční proteiny MeSH

We have examined the imprecision in the estimation of PCR efficiency by means of standard curves based on strategic experimental design with large number of technical replicates. In particular, how robust this estimation is in terms of a commonly varying factors: the instrument used, the number of technical replicates performed and the effect of the volume transferred throughout the dilution series. We used six different qPCR instruments, we performed 1-16 qPCR replicates per concentration and we tested 2-10 μl volume of analyte transferred, respectively. We find that the estimated PCR efficiency varies significantly across different instruments. Using a Monte Carlo approach, we find the uncertainty in the PCR efficiency estimation may be as large as 42.5% (95% CI) if standard curve with only one qPCR replicate is used in 16 different plates. Based on our investigation we propose recommendations for the precise estimation of PCR efficiency: (1) one robust standard curve with at least 3-4 qPCR replicates at each concentration shall be generated, (2) the efficiency is instrument dependent, but reproducibly stable on one platform, and (3) using a larger volume when constructing serial dilution series reduces sampling error and enables calibration across a wider dynamic range.

• Klíčová slova
• ANCOVA, analysis of covariance, Amplification efficiency, CLSI, Clinical and Laboratory Standards Institute, Cq, cycle of quantification, Dilution series, E, PCR efficiency, EPA, Environmental protection agency, FDA, food and Drug Administration, GMO, genetically modified organism, IEC, International Electrotechnical Commission, ISO, International Organization for Standardization, MIQE, minimum information for publication of quantitative real-time PCR experiments, NTC, no template control, RIN, RNA Integrity Number, RT-qPCR, reverse transcription-quantitative polymerase chain reaction, Real-time quantitative PCR, Standard curve, qPCR, qPCR assay validation,
• Publikační typ
• časopisecké články MeSH