Technical Variations in Low-Input RNA-seq Methodologies
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ABSTRACT:
ORGANISM(S): Mus musculus
PROVIDER: GSE50856 | GEO | 2014/01/13
SECONDARY ACCESSION(S): PRJNA219182
REPOSITORIES: GEO
Similar Datasets
Project description:Transcriptomics data obtained from limiting amounts of mRNA is often noisy, providing primarily qualitative changes in transcript expressions. So far, technical variations arising out of the library preparation protocols have not been adequately characterized at reduced levels of mRNA. Here, we generated sequencing libraries from limiting amounts of mRNA using three amplification-based methods, viz. Smart-seq, DP-seq and CEL-seq, and demonstrated significant technical variations in these libraries. Reduction in mRNA levels led to inefficient amplification of the majority of low to moderately expressed transcripts. Furthermore, stochasticity in primer hybridization and/or enzyme incorporation was magnified during the amplification step resulting in significant distortions in fold changes of the transcripts. Consequently, the majority of the differentially expressed transcripts identified were either high-expressed and/or exhibited high fold changes. High technical variations, which were sequencing depth independent, ultimately masked subtle biological differences mandating the development of improved amplification-based strategies for quantitative transcriptomics from limiting amounts of mRNA. Sequencing libraries were prepared from serial dilutions of mRNA, ranging from 1 ng to 25 pg, using three amplification-based methods, viz. Smart-seq, DP-seq and CEL-seq. The mRNA was derived from an in vitro model of lineage segregation achieved by modulating TGF beta signaling pathway in differentiating mouse embryonic stem cells.
2014-01-13 | E-GEOD-50856 | biostudies-arrayexpress
Project description:Intervention type:DRUG. Intervention1:Huaier, Dose form:GRANULES, Route of administration:ORAL, intended dose regimen:20 to 60/day by either bulk or split for 3 months to extended term if necessary. Control intervention1:None.
Primary outcome(s): For mRNA libraries, focus on mRNA studies. Data analysis includes sequencing data processing and basic sequencing data quality control, prediction of new transcripts, differential expression analysis of genes. Gene Ontology (GO) and the KEGG pathway database are used for annotation and enrichment analysis of up-regulated genes and down-regulated genes.
For small RNA libraries, data analysis includes sequencing data process and sequencing data process QC, small RNA distribution across the genome, rRNA, tRNA, alignment with snRNA and snoRNA, construction of known miRNA expression pattern, prediction New miRNA and Study of their secondary structure Based on the expression pattern of miRNA, we perform not only GO / KEGG annotation and enrichment, but also different expression analysis.. Timepoint:RNA sequencing of 240 blood samples of 80 cases and its analysis, scheduled from June 30, 2022..
| 2612481 | ecrin-mdr-crc
Project description:The goal of this study was to titrate the amount of adapters for picogram amounts of ChIP DNA to determine the optimal conditions for library generation. H3K4me3 ChIP DNA from human Raji cells was diluted to the indicated amount and sequencing libraries generated using a range of adapter concentrations. The optimal adapter:DNA ratios were sequenced in technical duplicate to determine the reproducibility at each starting ChIP DNA amount. Additionally, for two samples we altered the number of cycles during the PCR amplification to determine the effect of PCR on library complexity and read duplicates.
2020-08-20 | GSE71700 | GEO
Project description:Background: DNA microarrays provide a powerful method for global analysis of gene expression. The application of this technology to specific cell types and tissues, however, is typically limited by small amounts of available mRNA, thereby necessitating amplification. Here we compare microarray results obtained with two different methods of RNA amplification to profile gene expression in the C. elegans larval nervous system. Results: We used the mRNA-tagging strategy to isolate transcripts specifically from C. elegans larval neurons. The WT-Ovation Pico System (WT-Pico) was used to amplify 2 ng of Pan-neural RNA to produce labeled cDNA for microarray analysis. These WT-Pico-derived data were compared to microarray results obtained with a labeled aRNA target generated by two rounds of In Vitro Transcription (IVT) of 25 ng of Pan-neural RNA. WT-Pico results in a higher fraction of Present calls than IVT, a finding consistent with the proposal that DNA-DNA hybridization results in lower mismatch signals than the RNA-DNA heteroduplexes produced by IVT amplification. Microarray data sets from these samples were compared to a Reference profile of all larval cells to identify transcripts with elevated expression in neurons. These results were validated by the high proportion of known neuron-expressed genes detected in these profiles and by promoter-GFP constructs for previously uncharacterized genes in these data sets. Together, the IVT and WT-Pico methods identified 2,173 unique neuron-enriched transcripts. Only about half of these transcripts (1,044), however, are detected as enriched by both IVT and WT-Pico amplification. Conclusion: We show that two different methods of RNA amplification, IVT and WT-Pico, produce valid microarray profiles of gene expression in the C. elegans larval nervous system with a low rate of false positives. However, our results also show that each method of RNA amplification detects a unique subset of bona fide neural-enriched transcripts and thus a wider array of authentic neural genes are identified by the combination of these data sets than by the microarray profiles obtained with either method of RNA amplification alone. With its relative ease of implementation and greater sensitivity, WT-Pico is the preferred method of amplification for cases in which sample RNA is limiting. Keywords: expression profile
2007-11-01 | GSE9485 | GEO
Project description:In the teleost fish Fundulus heteroclitus there is extensive variation in gene expression among individuals within and between populations. Accurate measures of the variation in mRNA expression using microarrays can be confounded by technical variation, which includes variation in RNA isolation procedures, day of hybridization and methods used to amplify and dye label RNA for hybridization. In this manuscript we analyze the relationship between the amount of mRNA and the fluorescent signal from the microarray hybridizations demonstrating that for a wide-range of mRNA concentrations the fluorescent signal is a linear function of the amount of mRNA. Additionally, the separate isolation, labeling or hybridization of RNA does not add significant amounts of variation in microarray measures of gene expression. However, single or double rounds of amplification for labeling do have small but significant affects on 10% of genes, but this source of technical variation is easy to avoid. To examine both technical and stochastic biological variation, mRNA expression was measured from the same five individuals over a six-week time course. There were few, if any, meaningful differences in gene expression among time points. Thus, microarray measures using standard laboratory procedures can be precise and quantitative and are not subject to significant random biological noise.
2008-11-21 | GSE12858 | GEO
Project description:Objective: To develop a reliable, reproducible, and sensitive method for investigating gene-expression profiles from individual human oocytes. Setting: University medical center and university microarray laboratory. Patient(s): Couples undergoing intracytoplasmic sperm injection treatment were asked to donate their immature oocytes for research, and written informed consent was obtained in all cases. Seventy-nine human oocytes were used in total. Intervention(s): None. Main Outcome Measure(s): Amplification efficiency and microarray profiles. Result(s): Two of the five protocols (WT-Ovation One-Direct and Arcturus RiboAMp HS Plus) resulted in sufficient yields and high success rates and were further validated for their performance in obtaining reliable, reproducible, and sensitive expression profiles from individual human oocytes. Evaluation of these two protocols demonstrated that they both displayed low technical variation and produced highly reproducible profiles (r R 0.95). One of them identified significantly more transcripts but also had a higher number of false discoveries. Conclusion(s): Two protocols generated ample amounts of mRNA for (quantitative) polymerase chain reaction, microarray, and sequencing techniques. Further validation using a design that discriminates between biological and technical variation showed that both protocols can be used for gene-expression profiling of individual human oocytes.
2015-12-31 | GSE48141 | GEO
Project description:RNA-Seq analyses were performed in N. meningitidis strain Z5463 by deep sequencing using Ion Torrent technology (Thermo Fischer Scientific). For whole transcriptome libraries (mRNA+sRNA), cDNA libraries were prepared using the Ion Total RNA-Seq Kit v2 (Life Technologies) including a prior step of ribodepletion using specific probes adapted to N. meningitidis (Low Input Ribo Minus Eukaryote System v2) and size fractionation of RNA prior to cDNA synthesis with RNase III was performed. Briefly, 500 ng of total RNA were ribodepleted and then fragmented. After fragmentation, mean size of fragment was around 120 nt. Coding_and_NonCoding_R1, Coding_and_NonCoding_R2, and Coding_and_NonCoding_R3 represent three technical replicates. For sRNA libraries (sRNA), three cDNA libraries were prepared using the Ion Total RNA-Seq Kit v2 for Small RNA Libraries (Life Technologies) including a prior step of enrichment in small RNA fraction. Equal amounts of total RNA were used for the generation of all cDNA libraries. The three whole transcriptome libraries libraries (mRNA+sRNA) were then sequenced on an Ion ProtonTMSystem using the Ion PI Template and Sequencing OT 200 kit v3 and the 3 sRNA libraries were sequenced on an Ion PGM with the Hi-Q Template and Sequencing Kit using a 316 v2 array. NonCoding_R1, NonCoding_R2, and NonCoding_R3 represent three technical replicates.
2016-07-25 | E-MTAB-4768 | biostudies-arrayexpress
Project description:Single-cell whole-transcriptome analysis is a powerful tool for quantifying gene expression heterogeneity in populations of cells. Many techniques have, thus, been recently developed to perform transcriptome sequencing (RNA-Seq) on individual cells. To probe subtle biological variation between samples with limiting amounts of RNA, more precise and sensitive methods are still required. We adapted a previously developed strategy for single-cell RNA-Seq that has shown promise for superior sensitivity and implemented the chemistry in a microfluidic platform for single-cell whole transcriptome analysis. In this approach, single cells are captured and lysed in a microfluidic device, where mRNAs with poly(A) tails are reverse-transcribed into cDNA. Double-stranded cDNA is then collected and sequenced using a next-generation sequencing platform. We prepared 94 libraries consisting of single mouse embryonic cells and technical replicates of extracted RNA and thoroughly characterized the performance of this technology. Microfluidic implementation increased mRNA detection sensitivity as well as improved measurement precision compared with tube-based protocols. With 0.2M reads per cell, we were able to reconstruct a majority of the bulk transcriptome with 10 single cells. We also quantified variation between and within different types of mouse embryonic cells and found that enhanced measurement precision, detection sensitivity, and experimental throughput aided the distinction between biological variability and technical noise. With this work, we validated the advantages of an early approach to single-cell RNA-Seq and showed that the benefits of combining microfluidic technology with high-throughput sequencing will be valuable for large-scale efforts in single-cell transcriptome analysis. We investigated gene expression in mouse embryonic cells using microfluidic-facilitated RNA-Seq to analyze 56 single mouse ES cell (mESC) transcriptomes and 6 single mouse embryonic fibroblast (MEF) transcriptomes. To quantitatively evaluate the sensitivity and precision of our technique, we also sequenced 23 libraries from extracted mESC RNA, representing three sets of technical replicates with varying starting amounts of material.
2014-05-01 | E-GEOD-47835 | biostudies-arrayexpress
Project description:Zhao et al. Amplification Table 9 This experiment was designed to evaluate the effect of the amount of input total RNA on the fidelity, reproducibility, and yield of T7 based RNA linear amplification. BC2 total RNA was amplified using the Jeffrey lab protocol. Different amounts of T7 primer were used according to the quantity of input total RNA. Multiple amplifications were done for each quantity of input total RNA to minimize experimental variations. Set of arrays organized by shared biological context, such as organism, tumors types, processes, etc. Keywords: Logical Set
2005-11-04 | GSE3557 | GEO
Project description:Background: DNA microarrays provide a powerful method for global analysis of gene expression. The application of this technology to specific cell types and tissues, however, is typically limited by small amounts of available mRNA, thereby necessitating amplification. Here we compare microarray results obtained with two different methods of RNA amplification to profile gene expression in the C. elegans larval nervous system. Results: We used the mRNA-tagging strategy to isolate transcripts specifically from C. elegans larval neurons. The WT-Ovation Pico System (WT-Pico) was used to amplify 2 ng of Pan-neural RNA to produce labeled cDNA for microarray analysis. These WT-Pico-derived data were compared to microarray results obtained with a labeled aRNA target generated by two rounds of In Vitro Transcription (IVT) of 25 ng of Pan-neural RNA. WT-Pico results in a higher fraction of Present calls than IVT, a finding consistent with the proposal that DNA-DNA hybridization results in lower mismatch signals than the RNA-DNA heteroduplexes produced by IVT amplification. Microarray data sets from these samples were compared to a Reference profile of all larval cells to identify transcripts with elevated expression in neurons. These results were validated by the high proportion of known neuron-expressed genes detected in these profiles and by promoter-GFP constructs for previously uncharacterized genes in these data sets. Together, the IVT and WT-Pico methods identified 2,173 unique neuron-enriched transcripts. Only about half of these transcripts (1,044), however, are detected as enriched by both IVT and WT-Pico amplification. Conclusion: We show that two different methods of RNA amplification, IVT and WT-Pico, produce valid microarray profiles of gene expression in the C. elegans larval nervous system with a low rate of false positives. However, our results also show that each method of RNA amplification detects a unique subset of bona fide neural-enriched transcripts and thus a wider array of authentic neural genes are identified by the combination of these data sets than by the microarray profiles obtained with either method of RNA amplification alone. With its relative ease of implementation and greater sensitivity, WT-Pico is the preferred method of amplification for cases in which sample RNA is limiting. Experiment Overall Design: We profiled gene expression throughout the nervous system of the model organism Caenorhabditis elegans using two different amplification methods, WT-Pico and IVT (in vitro transcription). Since postembryonic cells are unattainable via this method, we used mRNA-tagging to isolate pan-neural RNAs from larval animals. In short, an epitope tagged poly-A binding protein (FLAG-PAB-1) was driven in all neurons using the F25B3.3 promoter. We then amplified harvested RNA using IVT or WT-Pico. Data generated from this study reveals significant differences between the two amplification methods. However, both seem to identify bona fide neural transcripts. Our work suggests that using two amplification methods, when possible, will provide one with a more accurate view of transcription in a particular cell type.
2008-06-16 | E-GEOD-9485 | biostudies-arrayexpress