scholarly journals Divergent gene expression levels between diploid and autotetraploid Tolmiea (Saxifragaceae) relative to the total transcriptome, the cell, and biomass

2017 ◽  
Author(s):  
Clayton J. Visger ◽  
Gane K-S. Wong ◽  
Yong Zhang ◽  
Pamela S. Soltis ◽  
Douglas E. Soltis

SummaryStudies of gene expression and polyploidy are typically restricted to characterizing differences in transcript concentration. Integrating multiple methods of transcript analysis, we document a difference in transcriptome size, and make multiple comparisons of transcript abundance in diploid and autotetraploid Tolmiea.We use RNA spike-in standards to identify and correct for differences in transcriptome size, and compare levels of gene expression across multiple scales: per transcriptome, per cell, and per biomass.In total, ~17% of all loci were identified as differentially expressed (DEGs) between the diploid and autopolyploid species. A shift in total transcriptome size resulted in only ~58% of the total DEGs being identified as differentially expressed following a per transcriptome normalization. When transcript abundance was normalized per cell, ~82% of the total DEGs were recovered. The discrepancy between per-transcriptome and per-cell recovery of DEGs occurs because per-transcriptome normalizations are concentration-based and therefore blind to differences in transcriptome size.While each normalization enables valid comparisons at biologically relevant scales, a holistic comparison of multiple normalizations provides additional explanatory power not available from any single approach. Notably, autotetraploid loci tend to conserve diploid-like transcript abundance per biomass through increased gene expression per cell, and these loci are enriched for photosynthesis-related functions.

2009 ◽  
Vol 21 (1) ◽  
pp. 196
Author(s):  
D. Tesfaye ◽  
N. Ghanem ◽  
F. Rings ◽  
E. Tholen ◽  
C. Phatsara ◽  
...  

The incidence of pregnancy loss due to embryonic mortality in cattle is one of the major causes of reproductive failure. The early embryonic loss can be due to problems with the embryo itself, the uterine environment, or interactions between the embryo and the uterus. So, this study was conducted to investigate the gene expression profile of bovine embryo biopsies produced in vivo and in vitro that resulted in different pregnancy outcomes. For this, biopsies representing 30 to 40% of the intact in vitro and in vivo blastocysts were taken, and 60 to 70% part was allowed to re-expand prior to transfer to recipients. Based on the pregnancy outcome after transfer, biopsies (n = 10 per pool) were grouped into 3 distinct phenotypes: those that resulted in no pregnancy, those that resulted in resorption, and those that resulted in successful pregnancy and subsequent calf delivery. A bovine cDNA microarray with 2000 clones was used to analyze the gene expression profiles of 3 replicates from each embryo biopsy group. Array data analysis revealed a total of 50 and 52 genes to be differentially expressed between biopsies derived from in vivo blastocysts that resulted in no pregnancy v. calf delivery and resorption v. calf delivery, respectively. Similarly, a total of 52 and 58 transcripts were differentially expressed between biopsies derived from in vitro-produced blastocysts that resulted in no pregnancy v. calf delivery and resorption v. calf delivery, respectively. Quantitative real-time PCR has confirmed the expression profile of 6 selected candidate genes. A distinct set of genes were found to be commonly expressed between in vitro- and in vivo-derived blastocyst biopsies, which ended up with the same pregnancy outcome. Biopsies, which ended up with calf delivery, were found to be enriched with transcripts involved in nucleosome assembly (KRT8), translation (RPLPO), electron transport (COX-2), and placenta specific (PLAC8). On the other hand, transcripts regulating immune response (TNFa), response to stress (HSPD1), and cell adhesion (CD9) were up-regulated in embryos that resulted in no pregnancy or resorption. Differences in transcript abundance of some genes have been seen between biopsies derived from in vitro and in vivo blastocysts. Biopsies from in vivo-derived blastocysts and that ended up with resorption were found to be enriched with transcripts regulating calcium-binding protein (S100A10, S100A14). Transcription factor-related transcripts (CDX2, HOXB7) were up-regulated in vitro-derived blastocyst biopsies that resulted in no pregnancy. In conclusion, the results evidenced that embryos derived from either in vitro or in vivo have more similarities than differences in their transcript abundance with respect to the ability in initiating pregnancy.


Blood ◽  
2007 ◽  
Vol 110 (11) ◽  
pp. 4734-4734
Author(s):  
Roberta S. Felix ◽  
Gisele W.B. Colleoni ◽  
Andre L. Vettore ◽  
Mihoko Yamamoto ◽  
Manuella S.S. Almeida ◽  
...  

Abstract Serial analysis of gene expression (SAGE) allows a comprehensive profiling of gene expression within a given tissue and also an assessment of transcript abundance. Objectives: We generated SAGE libraries from normal and neoplastic plasma cells with the aim of identifying genes differentially expressed in MM that could be useful as new potential diagnostic, prognostic markers or therapeutic targets. Material and methods: Normal plasma cells were obtained from palatine tonsils of 20 children who underwent tonsillectomy. MM SAGE library was obtained from bone marrow plasma cells of two IgGk newly diagnosed MM patients. Purified normal and neoplastic plasma cells were isolated after magnetic sorting of CD-138-positive cells. Results: We obtained 29,918 SAGE tags from normal and 10,340 tags from tumor libraries. Computer-generated genomic analysis identified 50 overexpressed genes in MM library. After comparison of unique tags expression levels, we selected 12 overexpressed (at least 10 times) genes in the MM library (ZFHX1B, XBP1, PIM2, LGALS1, RANBP2, P53CSV, DDX5, LSM5, JUND, MAPKAPK2, SP140 and NTN1) for further investigation. Expression of 10 out of 12 genes was validated by quantitative real-time PCR in purified plasma cells of 31 MM patients and three controls. XBP1, RANBP2, P53CSV, DDX5, MAPKAPK2 were overexpressed in at least 50% of MM cases. Comparative analyses of relative expression (2-D D CT) of the 10 genes in 31 MM cases and 3 controls showed statistically significant difference between cases and controls for all genes but PIM2 and ZHFX1B, confirming the SAGE data. Also, we could identify that RANBP2 and ZHFX1B have prognostic impact in MM OS (p = 0.040 and p = 0.0502, respectively). Multivariate analysis confirmed RANBP2 expression as a good independent prognostic marker. Conclusions: SAGE technique allowed the identification of genes differentially expressed in normal and neoplastic plasma cells. These genes may have important role in tumorigenesis or may be possible therapeutic targets for MM control, particularly P53CSV and MAPKAPK2, or prognostic impact, as RANBP2.


2010 ◽  
Vol 41 (3) ◽  
pp. 275-288 ◽  
Author(s):  
Monica M. Baze ◽  
Karen Schlauch ◽  
Jack P. Hayes

Hypoxia is an important ecological, evolutionary, and biomedical stressor. While physiological acclimatization of mammals to hypoxia is well studied, the variation in gene expression that underlies acclimatization is not well studied. We acclimatized inbred mice for 32 days to hypoxic conditions that simulated altitudes of 1400, 3000, and 4500 m. We used oligonucleotide microarrays to measure changes in steady-state abundance of mRNA in the livers of these mice. Mice exposed to more severe hypoxia (simulated altitude of 4500 m) were smaller in mass and had higher hematocrit than mice exposed to less severe hypoxia. ANOVA and false discovery rate tests indicated that 580 genes were significantly differentially expressed in response to chronic hypoxia. Few of these 580 genes have previously been reported to respond to hypoxia. In contrast, many of these 580 genes belonged to same functional groups typically respond to acute hypoxia. That is, both chronic and acute hypoxia elicit changes in transcript abundance for genes involved in angiogenesis, glycolysis, lipid metabolism, carbohydrate metabolism, and protein amino acid phosphorylation, but the particular genes affected by the two types of hypoxia were mostly different. Numerous genes affecting the immune system were differentially expressed in response to chronic hypoxia, which supports recently proposed hypotheses that link immune function and hypoxia. Furthermore, our results discovered novel elevated mRNA abundance of genes involved in hematopoiesis and oxygen transport not reported previously, but consistent with extreme hematocrits found in hypoxic mice.


2020 ◽  
Author(s):  
Ilona E. Grabowicz ◽  
Bartek Wilczyński ◽  
Bożena Kamińska ◽  
Adria-Jaume Roura ◽  
Bartosz Wojtaś ◽  
...  

AbstractGliomas are the most frequent primary tumors of the central nervous system (CNS) and encompass two major subgroups: diffuse, malignant gliomas and benign, well differentiated gliomas showing a more circumscribed growth. Genome-wide next generation sequencing studies have uncovered specific genetic alterations, transcriptomic patterns and epigenetic profiles associated with different types of gliomas improving tumor diagnosis and having important implications for future clinical trials and patient management. We have recently created a unique resource encompassing genome-wide profiles of open chromatin, histone H3K27ac and H3Kme3 modifications, DNA methylation and transcriptomes of 33 glioma samples of different grades. Here, we took advantage of a wealth of data from those high-throughput experiments, intersected those data with topologically associating domains (TADs) and demonstrated that the chromatin organization and epigenetic landscape of enhancers have a strong impact on genes differentially expressed in low grade versus high grade gliomas. We identified TADs enriched in glioma grade-specific genes and/or epigenetic marks. We found a set of transcription factors, including REST, E2F1 and NFKB1, that are most likely to regulate gene expression in multiple TADs, containing glioma-related genes. Moreover, many genes associated with the cell-matrix adhesion Gene Ontology group, in particular 14 PROTOCADHERINs, were found to be regulated by the long range contacts with enhancers. Overall, the results presented here demonstrate the existence of epigenetic differences associated with chromatin organization driving differential gene expression in gliomas of different malignancy. We demonstrated that integration of whole genome epigenetic data with Hi-C data and transcriptomic profiles described in this work, can segregate low and high grade gliomas and reveal new regulatory networks that could explain some of the functional differences between gliomas of different malignancies.HighlightsIntegration of ATAC-seq, ChIP-seq and RNA-seq reveals glioma malignancy-related gene regulatory networks.TADs segmentation contributes to gene-epigenetically modified enhancer relationships.Contacts of active enhancers in gliomas of different malignancies might affect expression of genes involved in cancerogenesis, such as PROTOCADHERINs or EGFR.


2000 ◽  
Vol 10 (12) ◽  
pp. 2055-2061
Author(s):  
Dov J Stekel ◽  
Yoav Git ◽  
Francesco Falciani

We describe a method for comparing the abundance of gene transcripts in cDNA libraries. This method allows for the comparison of gene expression in any number of libraries, in a single statistical analysis, to identify differentially expressed genes. Such genes may be of potential biological or pharmaceutical relevance. The formula that we derive is essentially the entropy of a partitioning of genes among cDNA libraries. This work goes beyond previously published analyses, which can either compare only two libraries, or identify a single outlier in a group of libraries. This work also addresses the problem of false positives associated with repeating the test on many thousands of genes. A randomization procedure is described that provides a quantitative measure of the degree of belief in the results; the results are further verified by considering a theoretically derived large deviations rate for the test statistic. As an example, the analysis is applied to four prostate cancer libraries from the Cancer Genome Anatomy Project. The analysis identifies biologically relevant genes that are differentially expressed in the different tumor cell types.


2014 ◽  
Vol 2014 ◽  
pp. 1-14 ◽  
Author(s):  
Prabhat Singh ◽  
Sharad Sharma ◽  
Srikanta Kumar Rath

Genistein is a soy derived isoflavone. It has wide variety of therapeutic effects against certain diseases including cancer. Although toxic effects of genistein have been studied, its effect on the gene expression and the reason behind toxicity have not been identified yet. In the present study, genistein was administered to age and body weight matched Swiss mice at the doses of 125, 250, 500 and 1000 mg/kg. The biomarkers of hepatotoxicity in serum, liver histology, oxidative stress parameters in tissue homogenates, and global gene expression were examined. Elevated alanine aminotransferase (ALT), aspartate aminotransferase (AST), and alkaline phosphatase (ALP) levels and degenerated liver tissue were observed in 500, and 1000 mg/kg genistein treated groups. Oxidative stress was significant at these doses as considerable increase in lipid peroxidation (LPO) and decrease in total glutathione (GSH) were observed. Gene expression analysis showed 40 differentially expressed genes at twofold change andP<0.05.Differentially expressed genes were corresponding to different biologically relevant pathways including metabolic and oxidative stress pathways. In 500 mg/kg group, Cyp4a14, Sult1e1, Gadd45g, Cidec, Mycs, and so forth genes were upregulated. These results suggested that the higher dose of genistein can produce several undesirable effects by affecting multiple cellular pathways.


2020 ◽  
Vol 26 (29) ◽  
pp. 3619-3630
Author(s):  
Saumya Choudhary ◽  
Dibyabhaba Pradhan ◽  
Noor S. Khan ◽  
Harpreet Singh ◽  
George Thomas ◽  
...  

Background: Psoriasis is a chronic immune mediated skin disorder with global prevalence of 0.2- 11.4%. Despite rare mortality, the severity of the disease could be understood by the accompanying comorbidities, that has even led to psychological problems among several patients. The cause and the disease mechanism still remain elusive. Objective: To identify potential therapeutic targets and affecting pathways for better insight of the disease pathogenesis. Method: The gene expression profile GSE13355 and GSE14905 were retrieved from NCBI, Gene Expression Omnibus database. The GEO profiles were integrated and the DEGs of lesional and non-lesional psoriasis skin were identified using the affy package in R software. The Kyoto Encyclopaedia of Genes and Genomes pathways of the DEGs were analyzed using clusterProfiler. Cytoscape, V3.7.1 was utilized to construct protein interaction network and analyze the interactome map of candidate proteins encoded in DEGs. Functionally relevant clusters were detected through Cytohubba and MCODE. Results: A total of 1013 genes were differentially expressed in lesional skin of which 557 were upregulated and 456 were downregulated. Seven dysregulated genes were extracted in non-lesional skin. The disease gene network of these DEGs revealed 75 newly identified differentially expressed gene that might have a role in development and progression of the disease. GO analysis revealed keratinocyte differentiation and positive regulation of cytokine production to be the most enriched biological process and molecular function. Cytokines -cytokine receptor was the most enriched pathways. Among 1013 identified DEGs in lesional group, 36 DEGs were found to have altered genetic signature including IL1B and STAT3 which are also reported as hub genes. CCNB1, CCNA2, CDK1, IL1B, CXCL8, MKI 67, ESR1, UBE2C, STAT1 and STAT3 were top 10 hub gene. Conclusion: The hub genes, genomic altered DEGs and other newly identified differentially dysregulated genes would improve our understanding of psoriasis pathogenesis, moreover, the hub genes could be explored as potential therapeutic targets for psoriasis.


2020 ◽  
Vol 15 ◽  
Author(s):  
Chen-An Tsai ◽  
James J. Chen

Background: Gene set enrichment analyses (GSEA) provide a useful and powerful approach to identify differentially expressed gene sets with prior biological knowledge. Several GSEA algorithms have been proposed to perform enrichment analyses on groups of genes. However, many of these algorithms have focused on identification of differentially expressed gene sets in a given phenotype. Objective: In this paper, we propose a gene set analytic framework, Gene Set Correlation Analysis (GSCoA), that simultaneously measures within and between gene sets variation to identify sets of genes enriched for differential expression and highly co-related pathways. Methods: We apply co-inertia analysis to the comparisons of cross-gene sets in gene expression data to measure the costructure of expression profiles in pairs of gene sets. Co-inertia analysis (CIA) is one multivariate method to identify trends or co-relationships in multiple datasets, which contain the same samples. The objective of CIA is to seek ordinations (dimension reduction diagrams) of two gene sets such that the square covariance between the projections of the gene sets on successive axes is maximized. Simulation studies illustrate that CIA offers superior performance in identifying corelationships between gene sets in all simulation settings when compared to correlation-based gene set methods. Result and Conclusion: We also combine between-gene set CIA and GSEA to discover the relationships between gene sets significantly associated with phenotypes. In addition, we provide a graphical technique for visualizing and simultaneously exploring the associations of between and within gene sets and their interaction and network. We then demonstrate integration of within and between gene sets variation using CIA and GSEA, applied to the p53 gene expression data using the c2 curated gene sets. Ultimately, the GSCoA approach provides an attractive tool for identification and visualization of novel associations between pairs of gene sets by integrating co-relationships between gene sets into gene set analysis.


BMC Genomics ◽  
2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Gregory M. Weber ◽  
Jill Birkett ◽  
Kyle Martin ◽  
Doug Dixon ◽  
Guangtu Gao ◽  
...  

Abstract Background Transcription is arrested in the late stage oocyte and therefore the maternal transcriptome stored in the oocyte provides nearly all the mRNA required for oocyte maturation, fertilization, and early cleavage of the embryo. The transcriptome of the unfertilized egg, therefore, has potential to provide markers for predictors of egg quality and diagnosing problems with embryo production encountered by fish hatcheries. Although levels of specific transcripts have been shown to associate with measures of egg quality, these differentially expressed genes (DEGs) have not been consistent among studies. The present study compares differences in select transcripts among unfertilized rainbow trout eggs of different quality based on eyeing rate, among 2 year classes of the same line (A1, A2) and a population from a different hatchery (B). The study compared 65 transcripts previously reported to be differentially expressed with egg quality in rainbow trout. Results There were 32 transcripts identified as DEGs among the three groups by regression analysis. Group A1 had the most DEGs, 26; A2 had 15, 14 of which were shared with A1; and B had 12, 7 of which overlapped with A1 or A2. Six transcripts were found in all three groups, dcaf11, impa2, mrpl39_like, senp7, tfip11 and uchl1. Conclusions Our results confirmed maternal transcripts found to be differentially expressed between low- and high-quality eggs in one population of rainbow trout can often be found to overlap with DEGs in other populations. The transcripts differentially expressed with egg quality remain consistent among year classes of the same line. Greater similarity in dysregulated transcripts within year classes of the same line than among lines suggests patterns of transcriptome dysregulation may provide insight into causes of decreased viability within a hatchery population. Although many DEGs were identified, for each of the genes there is considerable variability in transcript abundance among eggs of similar quality and low correlations between transcript abundance and eyeing rate, making it highly improbable to predict the quality of a single batch of eggs based on transcript abundance of just a few genes.


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Ying Xie ◽  
Xiaofeng Hang ◽  
Wensheng Xu ◽  
Jing Gu ◽  
Yuanjing Zhang ◽  
...  

Abstract Background Most of the biological functions of circular RNAs (circRNAs) and the potential underlying mechanisms in hepatocellular carcinoma (HCC) have not yet been discovered. Methods In this study, using circRNA expression data from HCC tumor tissues and adjacent tissues from the Gene Expression Omnibus database, we identified out differentially expressed circRNAs and verified them by qRT-PCT. Functional experiments were performed to evaluate the effects of circFAM13B in HCC in vitro and in vivo. Results We found that circFAM13B was the most significantly differentially expressed circRNA in HCC tissue. Subsequently, in vitro and in vivo studies also demonstrated that circFAM13B promoted the proliferation of HCC. Further studies revealed that circFAM13B, a sponge of miR-212, is involved in the regulation of E2F5 gene expression by competitively binding to miR-212, inhibits the activation of the P53 signalling pathway, and promotes the proliferation of HCC cells. Conclusions Our findings revealed the mechanism underlying the regulatory role played by circFAM13B, miR-212 and E2F5 in HCC. This study provides a new theoretical basis and novel target for the clinical prevention and treatment of HCC.


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