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Intratumoral fungus Neurospora crassa is associated with worsened prognosis in ovarian cancer via modulation of extracellular matrix.

Landmark studies on intratumoral fungi (ITF) have raised concerns due to irreproducible results and data-analysis errors. We aimed to determine whether ITF exist in ovarian cancer (OvCa) and, if so, whether they play a role in disease biology. Formalin-fixed, paraffin-embedded OvCa samples and multiple controls underwent operational decontamination, qPCR, internal transcribed spacer sequencing, and post-hoc data decontamination. We also leveraged updated fungal reads from The Cancer Genome Atlas generated by the TCMbio group, which addressed human-read contamination and artificial inflation, to validate findings and assess prognostic associations. A murine syngeneic model established using mouse ovarian cancer cell line (OVHM) with intratumoral Neurospora crassa injection was established. Transcriptomic and metabolomic analyses were performed to explore mechanisms. Tumor-containing blocks harbored significantly higher fungal loads than environmental controls but had loads comparable to paraffin controls. Applying a two-pass decontamination filter reduced raw sequence features from 9289 amplicon sequence variants (ASVs) to 659 ASVs. We focused on high-abundance features present in human tissues but absent from xenografts and paraffin controls and identified one candidate, N. crassa, associated with unfavorable prognosis in OvCa. Integrating human and murine data, we found Neurospora correlated with eosinophils, whereas N. crassa itself was not immune-related. Neurospora crassa promoted OvCa progression with downregulation of integrin-linked kinase and decreased extracellular matrix-receptor interaction. Most ITF signals are likely contaminants. We identified N. crassa as associated with unfavorable prognosis in OvCa, potentially via modulation of the extracellular matrix.

Neurospora crassa↗

Erythroid-induced commitment of K562 cells results in clusters of differentially expressed genes enriched for specific transcription regulatory elements.

Understanding regulation of fetal and embryonic hemoglobin expression is critical, since their expression decreases clinical severity in sickle cell disease and beta-thalassemia. K562 cells, a human erythroleukemia cell line, can differentiate along erythroid or megakaryocytic lineages and serve as a model for regulation of fetal/embryonic globin expression. We used microarray expression profiling to characterize transcriptomes from K562 cells treated for various times with hemin, an inducer of erythroid commitment. Approximately 5,000 genes were expressed irrespective of treatment. Comparative expression analysis (CEA) identified 899 genes as differentially expressed; analysis by the self-organizing map (SOM) algorithm clustered 425 genes into 8 distinct expression patterns, 322 of which were shared by both analyses. Differential expression of a subset of genes was validated by real-time RT-PCR. Analysis of 5'-flanking regions from differentially expressed genes by PAINT v3.0 software showed enrichment in specific transcription regulatory elements (TREs), some localizing to different expression clusters. This finding suggests coordinate regulation of cluster members by specific TREs. Finally, our findings provide new insights into rate-limiting steps in the appearance of heme-containing hemoglobin tetramers in these cells.

5' Flanking Region↗

Relationship between the tissue-specificity of mouse gene expression and the evolutionary origin and function of the proteins.

BACKGROUND: The combination of complete genome sequence information with expression data enables us to characterize the relationship between a protein's evolutionary origin or functional category and its expression pattern. In this study, mouse proteins were assigned into functional and phyletic groups and the gene expression patterns of the different protein groupings were examined by microarray analysis in various mouse tissues. RESULTS: Our results suggest that the proteins that are universally distributed in all tissues are predominantly enzymes and transporters. In contrast, the tissue-specific set is dominated by regulatory proteins (signal transduction and transcription factors). An increased tendency to tissue-specificity is observed for metazoan-specific proteins. As the composition of the phyletic groups highly correlates with that of the functional groups, the data were tested in order to determine which of the two factors -- function or phyletic age -- is dominant in shaping the expression profile of a protein. The observed differences in expression patterns of genes between functional groups were found mainly to reflect their different phyletic origin. The connection between tissue specificity and phyletic age cannot be explained by the recent rate of evolution. Finally, although metazoan-specific proteins tend to be tissue-specific compared with phyletically conserved proteins present in all domains of life, many such 'universal' proteins are also tissue-specific. CONCLUSION: The minimal cellular transcriptome of the metazoan cell differs from that of the ancestral unicellular eukaryote: new functions were added (metazoan-specific proteins), whilst other functions became specialized and no longer took place in all cells (tissue-specific pre-metazoan proteins).

Amino Acid Substitution↗

Tuberculosis: from genome to vaccine.

The availability of mycobacterial genome sequences has paved the way to identifying potential tuberculosis vaccine candidates in order to replace the currently used bacillus Calmette-Guérin (BCG) vaccines that show variable protective efficacy in adults. Genomics provides the basis for bioinformatic, transcriptomic and proteomic analysis, increases screening efficiency and enables valuable information concerning the biology and virulence of the mycobacterial species to be extracted by comparative genomics. Although in silico results must be confirmed in vitro and in vivo, bioinformatic analysis of the genomes is highlighting candidates for testing. For designing subunit vaccines, attenuated or improved recombinant whole-cell live vaccines, information from the genomes of the human host and pathogenic mycobacterial species is of great help.

Animals↗

The clinical and biological relationship between Type II diabetes mellitus and Alzheimer's disease.

The clinical relationship between Type II diabetes mellitus and Alzheimer's disease has been debated for over a decade. While several studies have not shown a clear clinical correlation, others have demonstrated that Type II diabetes is an independent risk factor for Alzheimer's disease. Why diabetes would increase the likelihood of Alzheimer's disease is not immediately clear, although recent studies have demonstrated an impact of insulin abnormalities, insulin resistance and advanced glycation end products on both the development of neural amyloid plaques and neurofibrillary tangles. Although endodermal in embryologic development, the pancreas is a highly innervated organ that shares a number of molecular similarities with brain at the level of the transcriptome and proteome. Type II diabetes and Alzheimer's disease are characterized by localized amyloid deposits that progress during the course of the disease. Comparing amyloid deposition in the brain and pancreas reveals some striking pathophysiologic similarities. Neurodegeneration in pancreatic islets, as manifested by neurofibrillary tangles, is less well studied than in Alzheimer's disease but may also occur. This review summarizes what is currently known about the clinical and biological relationships and similarities between Type II diabetes and Alzheimer's disease.

Alzheimer Disease↗

Hepatocyte dedifferentiation in 2D culture reveals extensive transcriptomic and proteomic rewiring.

BACKGROUND: Primary hepatocytes are commonly used in vitro to model liver metabolism, but prolonged culturing results in dedifferentiation and potentially limits the applicability of this model. METHODS: We characterized the transcriptome and proteome of full liver and primary hepatocytes as either freshly isolated cells or after 24 hours of 2D-culturing. RESULTS: We found that 2D-culturing for 24 hours changes more than 10,000 genes and 3000 proteins compared with freshly isolated cells, accompanied by a decrease in transcriptional heterogeneity and a loss of zonal markers. Moreover, there were changes in proteins associated with the extracellular matrix, in mitochondrial and ribosomal protein abundances, as well as an increase in the abundance of acute-phase response proteins. CONCLUSION: Collectively, primary mouse hepatocytes in culture rewire the transcriptome and proteome, which may affect the utility of this model to study physiological and molecular mechanisms related to the liver. We developed the Shiny app "Hepamorphosis" (https://cbmr.ku.dk/research/resources/shiny-apps/), which allows users to explore RNA/protein correlations, zonation profiles, and cell-type-specific transcription in full liver and cultured hepatocytes.

Hepatocytes↗

Multiple markers for melanoma progression regulated by DNA methylation: insights from transcriptomic studies.

The incidence of melanoma is increasing rapidly, with advanced lesions generally failing to respond to conventional chemotherapy. Here, we utilized DNA microarray-based gene expression profiling techniques to identify molecular determinants of melanoma progression within a unique panel of isogenic human melanoma cell lines. When a poorly tumorigenic cell line, derived from an early melanoma, was compared with two increasingly aggressive derivative cell lines, the expression of 66 genes was significantly changed. A similar pattern of differential gene expression was found with an independently derived metastatic cell line. We further examined these melanoma progression-associated genes via use of a tailored TaqMan Low Density Array (LDA), representing the majority of genes within our cohort of interest. Considerable concordance was seen between the transcriptomic profiles determined by DNA microarray and TaqMan LDA approaches. A range of novel markers were identified that correlated here with melanoma progression. Most notable was TSPY, a Y chromosome-specific gene that displayed extensive down-regulation in expression between the parental and derivative cell lines. Examination of a putative CpG island within the TSPY gene demonstrated that this region was hypermethylated in the derivative cell lines, as well as metastatic melanomas from male patients. Moreover, treatment of the derivative cell lines with the DNA methyltransferase inhibitor, 2'-deoxy-5-azacytidine (DAC), restored expression of the TSPY gene to levels comparable with that found in the parental cells. Additional DNA microarray studies uncovered a subset of 13 genes from the above-mentioned 66 gene cohort that displayed re-activation of expression following DAC treatment, including TSPY, CYBA and MT2A. DAC suppressed tumor cell growth in vitro. Moreover, systemic treatment of mice with DAC attenuated growth of melanoma xenografts, with consequent re-expression of TSPY mRNA. Overall, our data support the hypothesis that multiple genes are targeted, either directly or indirectly, by DNA hypermethylation during melanoma progression.

Animals↗

The skeletal muscle of aged male mice exhibits sustained growth regulatory transcriptional profile following glucocorticoid exposure compared with young males.

Excess glucocorticoids induce skeletal muscle myopathy by changing gene expression. Advanced age augments glucocorticoid-mediated muscle phenotypes, yet the transcriptional responses underlying those augmented phenotypes are unclear. The purpose of this study was to define the glucocorticoid-responsive transcriptome in young and aged muscle following both acute and more prolonged glucocorticoid treatment. Young (4-mo-old) or aged (24-mo-old) male mice were administered either an acute injection of dexamethasone (DEX) or vehicle or daily DEX or vehicle injections for 7 days. Muscles were harvested 6.5 h after the final or only injection. The tibialis anterior (TA) was selected for RNA sequencing analysis as DEX treatment lowered TA mass specifically in aged males. In silico analyses identified enriched pathways and transcription factors predicted to regulate DEX-sensitive genes. Acute DEX altered similar numbers of genes in young (950) versus aged males (913), although aged males had greater magnitudes of fold change. After 7 days of DEX treatment, aged muscle exhibited more DEGs compared with acute exposure (1,196 vs. 913), whereas young muscle exhibited fewer DEGs than after acute exposure (599 vs. 950). In aged males, glucocorticoid-sensitive genes were consistently enriched for growth regulatory processes across both time points, a pattern that was not evident in young males. Despite those age-associated transcriptional differences, the transcription factors predicted to regulate the glucocorticoid-sensitive genes were similar in young and aged males. These data expand our understanding into how aging modifies the transcriptional response to excess glucocorticoids in skeletal muscle.NEW & NOTEWORTHY Glucocorticoids promote mass loss in certain muscles with advanced age but not at younger ages. In a muscle whose mass is lost in response to elevated glucocorticoids only in advanced age in males, we show that glucocorticoids initiate a unique and exaggerated transcriptional profile after both acute exposure to the hormone and after prolonged treatment that is consistent with muscle atrophy. These findings expand our understanding of the effect primary aging has on glucocorticoid-induced atrophy in males.

Animals↗

Identification of CD36 as a new surface marker of marginal zone B cells by transcriptomic analysis.

Follicular (FO) B cells and marginal zone (MZ) B cells belong to the mature B cell population in spleen of mice. To identify new surface markers of these mature B cell subsets, we compared gene expression profiles of FO and MZ B cells by DNA microarray using FACS-sorted mouse FO and MZ B cells. From 14,000 mouse genes, 27 membrane proteins were expressed mainly in MZ B cells while another 22 membrane proteins expressed largely in FO B cells. Using FACS analysis, we identified that CD36, CD68, and CD49e were expressed on MZ B cells but not on FO B cells. In addition, using semi-quantitative PCR, we found that the mRNA of CD131 were much more abundant in MZ B cells. These results revealed new phenotypic properties of MZ and FO B cells, and would facilitate further studies in the differentiation and functions of these mature B cells.

Animals↗

Comparison of medulloblastoma and normal neural transcriptomes identifies a restricted set of activated genes.

Over 1.4 million transcript tags expressed in 20 different human medulloblastomas were counted using serial analysis of gene expression. Digital gene expression profiles in the medulloblastoma were compared to multiple regions of the normal human brain, revealing 30 transcripts with high expression in multiple tumors and little or no expression in the normal cerebellum and other adult and pediatric brain regions. Using independent medulloblastoma samples and normal tissue, real-time PCR verified eight of nine selected genes as candidate tumor-associated antigens. Differential protein expression for CD24, prolactin and Topo2A was further confirmed by immunohistochemical analysis using medulloblastoma and normal brain sections and a tissue microarray. The genes highly expressed in the medulloblastoma include PRAME, a cancer-testis antigen and potential targets for immunotherapy.

Brain↗

Evolutionary Reorganization of Transcriptomic Architecture Across a UVB Tolerance Gradient in Fish.

Environmental stressors such as ultraviolet radiation impose strong selective pressures on organisms, yet how adaptation to such stressors shapes transcriptomic responses at the network level remains poorly understood. Although stratospheric ozone is recovering globally, substantial regional variation in UV exposure persists, particularly in high-altitude environments where extreme UV levels can occur. Here, we compared three fish models representing distinct biological responses to UVB exposure: wild-type zebrafish (Danio rerio), a melanin-deficient zebrafish mutant (nacre) lacking a major protective mechanism against UVB damage, and the high-altitude Andean killifish Orestias ascotanensis, a species naturally exposed to extreme UVB radiation. Together, these models define a gradient spanning physiological protection, impaired protection, and evolutionary adaptation to UVB stress. Using RNA-seq and protein-protein interaction networks, we show that transcriptomic responses differ markedly across this gradient. Wild-type and nacre zebrafish exhibited relatively limited transcriptomic changes (∼2%-2.4% of genes changing), whereas O. ascotanensis displayed a large-scale and highly coordinated response (∼21.6% of genes changing) characterized by functionally specialized networks enriched in DNA repair pathways. These differences involved not only transcriptomic magnitude but also marked reorganization of transcriptomic architecture. Integration with positive selection analyses revealed that positively selected genes were concentrated within highly interconnected regions of transcriptomic networks, consistent with adaptation involving network reorganization. Furthermore, ortholog-based analyses suggest that adaptive responses involve differential reorganization of a conserved functional background. Together, our results support a model in which adaptation to environmental stress is associated with the reorganization of conserved transcriptomic networks across physiological and evolutionary contexts, providing a systems-level perspective on the molecular basis of adaptation.

UVB radiation↗

Wound healing in Atlantic spiny dogfish sharks.

Field observations and limited experimental studies indicate that elasmobranchs can repair substantial skin injuries, but the temporal course and cellular composition of wound healing in Atlantic spiny dogfish remain poorly characterized. We conducted an exploratory laboratory study in 20 female Atlantic spiny dogfish (Squalus acanthias) using standardized full-thickness skin wounds monitored by serial photography for 35 days, histological analysis at defined post-injury time points, and pooled single-nucleus RNA sequencing of intact and wounded skin. A continuous neoepithelial layer covered all examined wound beds by Day 1, whereas macroscopic wound area decreased progressively over 35 days and dermal denticles remained absent from the repaired surface. Histological examination showed progressive neoepidermal maturation, basement-membrane reformation, collagen deposition, and granulation-tissue organization, indicating that epithelial coverage preceded restoration of normal skin architecture. Single-nucleus RNA sequencing identified epithelial, stromal, vascular, pigment, neural, and immune-cell populations. T and B cells were detected in intact skin, and their relative abundance, together with that of several other leukocyte populations, increased at Day 1 and generally declined by Day 14. Because samples were pooled by time point, these transcriptomic changes are descriptive. These findings characterize rapid early reepithelialization followed by slower tissue remodeling in Atlantic spiny dogfish and provide a foundation for future comparative studies of elasmobranch skin repair.

Animals↗

The FunCat, a functional annotation scheme for systematic classification of proteins from whole genomes.

In this paper, we present the Functional Catalogue (FunCat), a hierarchically structured, organism-independent, flexible and scalable controlled classification system enabling the functional description of proteins from any organism. FunCat has been applied for the manual annotation of prokaryotes, fungi, plants and animals. We describe how FunCat is implemented as a highly efficient and robust tool for the manual and automatic annotation of genomic sequences. Owing to its hierarchical architecture, FunCat has also proved to be useful for many subsequent downstream bioinformatic applications. This is illustrated by the analysis of large-scale experiments from various investigations in transcriptomics and proteomics, where FunCat was used to project experimental data into functional units, as 'gold standard' for functional classification methods, and also served to compare the significance of different experimental methods. Over the last decade, the FunCat has been established as a robust and stable annotation scheme that offers both, meaningful and manageable functional classification as well as ease of perception.

Abstracting and Indexing↗

SYSTOMONAS--an integrated database for systems biology analysis of Pseudomonas.

To provide an integrated bioinformatics platform for a systems biology approach to the biology of pseudomonads in infection and biotechnology the database SYSTOMONAS (SYSTems biology of pseudOMONAS) was established. Besides our own experimental metabolome, proteome and transcriptome data, various additional predictions of cellular processes, such as gene-regulatory networks were stored. Reconstruction of metabolic networks in SYSTOMONAS was achieved via comparative genomics. Broad data integration is realized using SOAP interfaces for the well established databases BRENDA, KEGG and PRODORIC. Several tools for the analysis of stored data and for the visualization of the corresponding results are provided, enabling a quick understanding of metabolic pathways, genomic arrangements or promoter structures of interest. The focus of SYSTOMONAS is on pseudomonads and in particular Pseudomonas aeruginosa, an opportunistic human pathogen. With this database we would like to encourage the Pseudomonas community to elucidate cellular processes of interest using an integrated systems biology strategy. The database is accessible at http://www.systomonas.de.

Bacterial Proteins↗

Heat shock proteome analysis of wild-type Corynebacterium glutamicum ATCC 13032 and a spontaneous mutant lacking GroEL1, a dispensable chaperone.

Proteome analysis of Corynebacterium glutamicum ATCC 13032 showed that levels of several proteins increased drastically in response to heat shock. These proteins were identified as DnaK, GroEL1, GroEL2, ClpB, GrpE, and PoxB, and their heat response was in agreement with previous transcriptomic results. A major heat-induced protein was absent in the proteome of strain 13032B of C. glutamicum, used for genome sequencing in Germany, compared with the wild-type ATCC 13032 strain. The missing protein was identified as GroEL1 by matrix-assisted laser desorption ionization-time of flight peptide mass fingerprinting, and the mutation was found to be due to an insertion sequence, IsCg1, that was integrated at position 327 downstream of the translation start codon of the groEL1 gene, resulting in a truncated transcript of this gene, as shown by Northern analysis. The GroEL1 chaperone is, therefore, dispensable in C. glutamicum. On the other hand, GroEL2 appears to be essential for growth. Based on these results, the role of the duplicate groEL1 and groEL2 genes is analyzed.

Bacterial Proteins↗

TNIK Overexpression Is Sufficient for Chemoradiation Resistance in Limited-Stage Small Cell Lung Cancer.

Small cell lung cancer (SCLC) is characterized by early metastasis, intrinsic chemoradiation resistance, and tumor recurrence. Besides the lack of potentially targetable oncogenic drivers, therapeutic advancements are also hindered by the scarcity of surgically resected tissue specimens ideal for profiling studies. We used patient-derived xenografts (PDX) to model SCLC chemoradiation resistance and identified chemoradiation resistance candidate genes using RNA sequencing. Additionally, we used human SCLC cell lines to confirm our in vivo results and delineate the underlying mechanism. Transcriptome profiling showed that the Traf2- and Nck-interacting kinase (TNIK) gene was consistently upregulated in an array of SCLC PDXs exposed to chemoradiation compared with monotherapy, which is consistent with previous observations of TNIK amplification in human samples. Genetic depletion (P < 0.01) or pharmacologic inhibition (P < 0.0001) of TNIK reduced in vitro clonogenic survival of TNIKhigh SCLC cells and promoted sensitivity to chemoradiation. In vivo, pharmacologic inhibition of TNIK enhanced chemoradiation sensitivity (P < 0.0001) of the H446 cell line-derived xenograft (CDX) in NOD-SCID mice. Furthermore, pharmacologic inhibition of TNIK in vivo demonstrated sensitivity (P < 0.0001) to chemoradiotherapy (CRT) in LX33 PDX. These results indicate that TNIK plays a role in conferring resistance to chemoradiation in SCLC cell lines and in vivo in SCLC CDX and PDX models. Delineating the mechanism behind radiosensitization suggested that TNIK inhibition may impair the DNA damage response in irradiated cells. Collectively, these findings suggest that TNIK may be a promising therapeutic target in limited-stage SCLC and support further investigation of TNIK inhibition in combination with standard CRT.

Humans↗

Bioinformatics of the Paracoccidioides brasiliensis EST Project.

Paracoccidioides brasiliensis is the etiological agent of paracoccidioidomycosis, an endemic mycosis of Latin America. This fungus presents a dimorphic character; it grows as a mycelium at room temperature, but it is isolated as yeast from infected individuals. It is believed that the transition from mycelium to yeast is important for the infective process. The Functional and Differential Genome of Paracoccidioides brasiliensis Project--PbGenome Project was developed to study the infection process by analyzing expressed sequence tags--ESTs, isolated from both mycelial and yeast forms. The PbGenome Project was executed by a consortium that included 70 researchers (professors and students) from two sequencing laboratories of the midwest region of Brazil; this project produced 25,741 ESTs, 19,718 of which with sufficient quality to be analyzed. We describe the computational procedures used to receive process, analyze these ESTs, and help with their functional annotations; we also detail the services that were used for sequence data exploration. Various programs were compared for filtering and grouping the sequences, and they were adapted to a user-friendly interface. This system made the analysis of the differential transcriptome of P. brasiliensis possible.

Brazil↗

Dynamics and variability of transcriptomic dysregulation in congenital myotonic dystrophy during pediatric development.

Myotonic dystrophy type 1 (DM1) is a multi-systemic disorder caused by expansion of CTG microsatellite repeats within DMPK. The most severe form, congenital myotonic dystrophy (CDM), has symptom onset at birth due to large intergenerational repeat expansions. Despite a common mutation, CDM individuals present with a distinct clinical phenotype and absence of common DM1 symptoms. Given the clinical divergence, it is unknown if the hallmark of DM1 pathology, dysregulation of alternative splicing (AS) due to sequestration of MBNL proteins within toxic CUG repeat RNAs, contributes to disease throughout pediatric development. To evaluate global transcriptomic dysregulation, RNA-seq was performed on 36 CDM skeletal muscle biopsies ages 2 weeks to 16 years, including two longitudinal samples. Fifty DM1 and adult/pediatric controls were also sequenced as comparative groups. Despite a large CTG expansion and shared age of onset, CDM individuals presented with a heterogenous, MBNL-dependent mis-splicing signature. Estimation of intracellular MBNL concentrations from splicing responses of select events correlated with total spliceopathy and revealed a distinct, triphasic pattern of AS dysregulation across pediatric development. CDM infants (< 2 years) possess severe mis-splicing that significantly improves in early childhood (2-8 years) independent of sex or CTG repeat load. Adolescent individuals (8-16 years) stratified into two populations with a full range of global splicing dysregulation. DMPK expression changes correlated with alterations in splicing severity during development. This study reveals the complex dynamics of the CDM muscle transcriptome and provides insights into new therapeutic strategies, timing of therapeutic intervention, and biomarker development.

Child, Preschool↗