Correction for Grünig et al., Evolution after whole-genome duplication (WGD) drives phenotypic and transcriptomic divergence more than WGD in an autopolyploid herb.
Explore the source record for details and available documents.
Journal Article↗
SEARCH · Search PubMed
Results for “whole transcriptome”
Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.
Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.
Multi-omics integrative analysis provides insight into potential molecular responses to sustained high water flow in common carp (Cyprinus carpio) cultured in recirculating aquaculture.
To investigate the potential molecular responses by which water flow intensity affects the growth of common carp (Cyprinus carpio) in a recirculating aquaculture system (RAS), a control group (CG, actual water velocity 0.3 cm/s) and three sustained flow treatment groups were established, including a low-flow group (LF, 1 body length per second, bl/s), a medium-flow group (MF, 2 bl/s), and a high-flow group (HF, 3 bl/s). After 12 weeks of culture in the RAS, growth performance was compared among groups under different flow intensities. The best-performing group and the control group were then selected for the determination of intestinal digestive enzyme activities, as well as transcriptomic and whole-genome bisulfite sequencing analyses of muscle tissue. The results showed that the specific growth rate and feed intake of the HF group were significantly higher than those of the other groups (P < 0.05), whereas no significant difference in feed conversion ratio was observed among groups. Compared with the CG group, lipase activity was significantly higher in the HF group (P < 0.05), while α-amylase and trypsin activities showed increasing trends without significant differences. RNA-seq identified a total of 273 differentially expressed genes, including 72 upregulated genes and 201 downregulated genes in the HF group relative to the CG group. These genes were mainly enriched in glycolysis, pyruvate metabolism, ATP metabolism, the pentose phosphate pathway, the insulin signaling pathway, the PPAR signaling pathway, and the adipocytokine signaling pathway, indicating that sustained high water flow induced a muscle transcriptional response characterized by remodeling of energy metabolism and substrate utilization. Whole-genome bisulfite sequencing analysis showed that DNA methylation in common carp muscle occurred predominantly in the CpG context. Differentially methylated regions between the HF and CG groups were mainly distributed in transcription-related regulatory regions, including promoters, CpG islands, and CpG island shores. In promoter regions, the number of hypermethylated regions in the HF group relative to the CG group was markedly higher than that of hypomethylated regions. Integrated analysis further identified two candidate genes showing both promoter differential methylation and differential expression, namely LOC109094644 and bcorl1, suggesting that adaptation to high water flow may involve IGF-related growth regulation and remodeling of upstream transcriptional programs. The qPCR results were consistent with the transcriptomic data. Taken together, within the tested range, a sustained water flow of 3 bl/s was more conducive to the growth of common carp in the RAS, which may be associated with enhanced lipid digestion and utilization, remodeling of the muscle energy metabolic network, changes in promoter methylation, and the coordinated regulation of key candidate genes. This study provides a theoretical basis for clarifying the exercise adaptation mechanism of common carp in recirculating aquaculture and for optimizing flow velocity parameters.
Animals↗
A new tool for rheumatology: large-scale analysis of gene expression.
Large-scale analysis of gene expression with cDNA arrays is spreading over many biological fields, including rheumatology. In this report, we wish to explain the principle and main advantages of this tool in the context of our discipline. Until 1995, analysis of gene expression was conducted for a few genes at a time but DNA chips now allow one to monitor the expression of thousands of genes in a single experiment and analyze the transcriptome, i.e. the whole of the transcripts in a given cell or tissue. Whatever the platform used (macro- or microarrays, oligo-chips), this technology rests upon the hybridization of i) a set of cDNA clones tethered to a solid support (nylon or glass) as probes, and ii) labelled cDNAs that are reverse-transcribed from bulk mRNAs extracted from a cell or tissue sample as a target. The end result is information on the relative abundance of every mRNA between two or more samples. The transcriptome analysis has two main objectives in rheumatology: i) identifying a gene expression profile that is a hallmark of a pathology and using it for a diagnostic or prognostic purpose, and ii) gathering genes with similar changes of expression, which allows one to specify the identity of novel proteins involved in a well-known intracellular cascade of regulation or even to identify new cascades.
Arthritis, Rheumatoid↗
Tripterygium Glycosides Alleviates Hemophagocytic Lymphohistiocytosis Accompanied With Aggressive NK Cell Leukemia and Epstein-Barr Virus Infection.
Hemophagocytic lymphohistiocytosis (HLH) is a group of hyperinflammatory disorders with a mortality rate exceeding 50%. We report a case of a female Asian patient who developed secondary HLH accompanied by aggressive natural killer cell leukemia and Epstein-Barr virus (EBV) infection, and was treated with tripterygium glycosides (TG), a Chinese patent medicine. Within 3 weeks of oral administration, the patient's recurrent high fever resolved, abdominal distension and splenomegaly improved, ascites diminished, serum soluble CD25 levels decreased, and hematopoietic and coagulation functions recovered. Triptolide, a major component of TG, exhibited cytotoxicity against the patient's ascitic cells and induced apoptosis in a dose-dependent manner ex vivo. Whole-genome and transcriptome sequencing of the patient's tumor cells revealed that TG regulated EBV-associated mutated genes such as PSMD7 and modulated inflammation-related pathways. Molecular docking further suggested direct targeting of PSMD7 by triptolide. Tripterygium glycosides quickly mitigated cytokine storm, alleviated symptoms of HLH, and showed no observed adverse effects with a good cost-benefit profile, thereby offering a potential bridge for follow-up hematopoietic stem cell transplantation.
Humans↗
Genome-wide scan reveals that genetic variation for transcriptional plasticity in yeast is biased towards multi-copy and dispensable genes.
One of the most important aspects of the evolution of development and physiology is the interplay between gene expression and the environment, by which traits become altered in response to environmental triggers. This feature is known as phenotypic plasticity. When different genotypes show different levels of plasticity for a trait, then they show genotype-by-environment interaction, or GEI. It is now clear that gene expression plays an important role in organismic-level phenotypic plasticity, but we know very little about whether gene expression itself is subject to genetic variation for phenotypic plasticity (GEI). Given that gene regulation is likely to have evolved to respond to environmental changes, it is of central importance to understand how environmental and genetic variation interact to produce variation in gene expression. Here we investigate genetic variation for phenotypic plasticity in the yeast transcriptome for the whole genome. Six strains of Saccharomyces cerevisiae were grown in four different environments representing a continuum of rich and poor natural conditions. Using DNA-microarray data and an ANOVA analysis with a stringent criterion of significance, we found significant genetic variation for transcriptional plasticity (GEI) among strains for approximately 5% of the genes in the genome. There are about twice as many genes that show genetic variation for phenotypic plasticity as show genetic variation in transcription level independent of the environment. We also found that genes with genetic variation for plasticity were less likely to be essential and were significantly biased towards genes that have paralogs.
Adaptation, Physiological↗
Emergence of cefiderocol resistance in carbapenem-resistant Escherichia coli ST167 prior to clinical use: A multifactored resistance landscape.
OBJECTIVES: Cefiderocol is a novel siderophore cephalosporin with potent activity against multidrug-resistant Gram-negative bacteria. Here, we reported the prevalence and mechanisms of cefiderocol resistance in carbapenem-resistant Escherichia coli (CREC) in China before its clinical use. METHODS: A total of 443 non-duplicate CREC isolates collected from 67 hospitals in China (2013-2021) underwent antimicrobial susceptibility testing according to CLSI guidelines. Whole-genome sequencing, transcriptomic analysis, siderophore quantification, and targeted genetic manipulation were performed to investigate the underlying resistance mechanisms. RESULTS: Among the 443 CREC isolates, 102 (23.0%) were resistant to cefiderocol, and 34 (7.6%) showed intermediate susceptibility. Multivariable logistic regression identified ST167 lineage (OR, 3.05; 95% CI, 1.12-8.29; P = 0.028), blaNDM-5 carriage (OR, 9.04; 95% CI, 2.96-27.57; P < 0.001), and cirA truncation (OR, 49.56; 95% CI, 20.33-120.79; P < 0.001) as independent factors associated with cefiderocol resistance. Among ST167 isolates, cefiderocol-resistant isolates showed increased yersiniabactin carriage and siderophore production but comparable TonB-dependent transporter expression profiles. Phylogenetic analysis revealed that cefiderocol-resistant ST167 isolates clustered into a distinct subclade enriched with resistance-associated determinants, including a recurrent FhuA P50S substitution detected in 59/64 (92.2%) resistant isolates. Functional assays showed that the P50S substitution increased cefiderocol minimum inhibitory concentration (0.032-0.125 µg/mL), particularly in an NDM-5-producing background (0.032-0.5 µg/mL). CONCLUSIONS: Cefiderocol resistance is highly prevalent among high-risk ST167 CREC isolates before the clinical introduction of cefiderocol in China, highlighting the need for continued surveillance of this epidemic lineage. Cefiderocol resistance is mediated by multiple resistance determinants, and we identify the recurrent FhuA P50S substitution as a novel contributor to reduced cefiderocol susceptibility.
Antimicrobial resistance↗
Functional identification of the key gene Eh-fadB in nicosulfuron degradation by Enterobacter hormaechei ES1 based on multi-omics and enzymatic characterization.
Nicosulfuron is a sulfonylurea herbicide with residues that pose ecological risks in agricultural soils. Here we elucidated the degradation mechanism of Enterobacter hormaechei ES1 through whole-genome sequencing, transcriptomics, metabolomics, gene knockout, heterologous expression, and soil bioremediation assays. Under nicosulfuron stress, ES1 upregulated antioxidant enzymes including SOD, POD, and CAT, along with glutathione synthesis, to scavenge excess reactive oxygen species. HPLC-TOF-MS identified degradation intermediates such as ADMP and ASDM, indicating initial cleavage of the sulfonylurea bridge. Integrated multi-omics prioritized Eh-fadB, encoding a fatty acid β-oxidation multifunctional enzyme, as a novel degradative gene. Targeted knockout of Eh-fadB reduced nicosulfuron degradation from 87.6% to 37.04%, while genetic complementation restored nearly full activity. Purified Eh-FadB directly converted nicosulfuron, with optimal performance at 30 °C and pH 5-6; its activity was enhanced by Na+ and Pb2+ but inhibited by Fe3+. Molecular docking and dynamics identified His-450 and Asn-427 as key residues for substrate binding. In contaminated soil, inoculation with ES1 reduced nicosulfuron content within 21 days and promoted recovery of dehydrogenase and urease activities. This study provides the first genetic and biochemical evidence that a FadB-type enzyme participates in nicosulfuron catabolism, supporting sulfonylurea bridge cleavage and its potential for soil bioremediation.
Eh-fadB↗
Transmitochondrial pigs reveal causal effects of mitochondrial DNA on backfat thickness via nuclear epigenetic reprogramming.
Mitochondrial DNA (mtDNA) polymorphisms have been associated with production traits in farm animals, including backfat thickness in pigs, yet direct in vivo evidence establishing a causal link between specific mtDNA haplotypes and fat deposition remains limited. In this study, we generated transmitochondrial pigs (mitopigs) by combining the Dapulian nuclear genome with Wuzhishan mtDNA via somatic cell nuclear transfer, introducing 23 mtDNA mutations relative to controls. Mitopigs exhibited significantly increased backfat thickness at 5 months, a difference that persisted in their offspring, without significant differences in body weight, body size, or litter size. Fibroblasts derived from mitopigs exhibited reduced mtDNA copy numbers, decreased expression of mitochondrial biogenesis genes (PPARA, PPARGC1A, RRM2B, and LRPPRC), impaired mitochondrial respiration, elevated reactive oxygen species (ROS), and upregulated adipogenic transcription factors (CEBPA, CEBPB, and PPARG). Consistent with these fibroblast findings, backfat tissue of mitopigs showed corresponding upregulation of adipogenic transcription factors and downregulation of mitochondrial biogenesis genes. Integrated transcriptomic and whole-genome bisulfite sequencing (WGBS) analyses revealed nuclear transcriptional reprogramming that was closely associated with differential DNA methylation, predominantly affecting mitochondrial function and lipid metabolism pathways. Mitopig fibroblasts also showed a pro-inflammatory response to lipopolysaccharide stimulation, with elevated expression of IL-12, NOS2, RELA, and TNF-α. Our findings provide direct in vivo evidence that mtDNA variants regulate adiposity in pigs through mitochondrial dysfunction, oxidative stress, and nuclear epigenetic modulation, highlighting the potential for incorporating mtDNA haplotype information into pig breeding programs as a complementary strategy to nuclear genomic selection.
Adipogenesis↗
Nanobioreactor detection of space-associated hematopoietic stem and progenitor cell aging.
Human hematopoietic stem and progenitor cell (HSPC) fitness declines following exposure to stressors that reduce survival, dormancy, telomere maintenance, and self-renewal, thereby accelerating aging. While previous National Aeronautics and Space Administration (NASA) research revealed immune dysfunction in low-earth orbit (LEO), the impact of spaceflight on human HSPC aging had not been studied. To study HSPC aging, our NASA-supported Integrated Space Stem Cell Orbital Research (ISSCOR) team developed bone marrow niche nanobioreactors with lentiviral bicistronic fluorescent, ubiquitination-based cell-cycle indicator (FUCCI2BL) reporter for real-time HSPC tracking in artificial intelligence (AI)-driven CubeLabs. In month-long International Space Station (ISS) missions (SpX-24, SpX-25, SpX-26, and SpX-27) compared with ground controls, FUCCI2BL reporter, whole-genome and transcriptome sequencing, and cytokine arrays demonstrated cell-cycle, inflammatory cytokine, mitochondrial gene, human repetitive element, and apolipoprotein B mRNA editing enzyme, catalytic polypeptide-like 3 (APOBEC3) deregulation together with clonal hematopoietic mutations. Furthermore, HSPC functionally organized multi-omics aging (HSPC-FOMA) analyses revealed reduced telomere maintenance, adenosine deaminase acting on RNA1 (ADAR1) p150 self-renewal gene expression, and replating capacity indicative of space-associated HSPC aging that may limit long-duration spaceflight.
Humans↗
Gene expression changes induced by estrogen and selective estrogen receptor modulators in primary-cultured human endometrial cells: signals that distinguish the human carcinogen tamoxifen.
Tamoxifen has long been the endocrine treatment of choice for women with breast cancer and is now employed for prophylactic use in women at high risk from breast cancer. Other selective estrogen receptor modulators (SERMs), such as raloxifene, mimic some of tamoxifen's beneficial effects and, like tamoxifen, exhibit a complex mixture of organ-specific estrogen agonist and antagonistic properties. However, accompanying the positive effects of tamoxifen has been the emergence of evidence for an increased risk of endometrial cancer associated with its use. A more complete understanding of the mechanism(s) of SERM carcinogenicity and endometrial effects is therefore required. We have sought to compare and characterise the transcript profile of tamoxifen, raloxifene and the agonist estradiol in human endometrial cells. Using primary cultures of human endometria, to best emulate the in vivo responses in a manageable in vitro system, we have shown 230 significant changes in gene expression for epithelial cultures and 83 in stromal cultures, either specific to 17beta-estradiol, tamoxifen or raloxifene, or changed across more than one of the treatments. Considering the transcriptome as a whole, the endometrial responses to raloxifene or tamoxifen were more similar than either drug was to 17beta-estradiol. Treatment of endometrial cultures with tamoxifen resulted in the largest number of gene changes relative to control cultures and a high proportion of genes associated with regulation of gene transcription, cell-cycle control and signal transduction. Tamoxifen-specific changes that might point towards mechanisms for its proliferative response in the endometrium included changes in retinoblastoma and c-myc binding proteins, the APCL, dihydrofolate reductase (DHFR) and E2F1 genes and other transcription factors. Tamoxifen was also found to give rise to the highest number of gene expression changes common to those that characterise malignant endometria. It is anticipated that this study will provide leads for further and more focused investigation into SERM carcinogenicity.
Cells, Cultured↗
The DLX/Notch axis is necessary for spatiotemporal regulation of neural cell fate.
Neuronal-glial cell fate switch during forebrain development is highly regulated. DLX transcription factors are necessary for promoting GABAergic interneuron differentiation and migration but the mechanisms for concomitant repression of glial fate in neural progenitors remain elusive. Here, the DLX2 regulatory network dynamic in the developing ventral telencephalon is characterised using a multi-omic approach at single-cell resolution, including single-cell whole genome spatial transcriptomics. We identify a secondary proliferative zone in the ventral subventricular zone and spatiotemporal-context dependent Notch pathway repression by DLX2 in maintaining progenitor populations and facilitating neural differentiation. We find that DLX2 controls cell fate determination by directly repressing Notch signalling genes as well as glial fate-promoting transcription factors, thereby inhibiting early adoption of oligodendroglial differentiation during neurogenesis. Here, we show that temporal cell fate switch is mediated by DLX2 via a multilayer gene regulatory network, redefining current understanding of neuronal-glial cell specification mechanisms in the developing telencephalon.
Animals↗
Identifying causal genetic variants for high-altitude adaptation through blood eQTL analysis in plateau populations.
A substantial number of genetic variants have been associated with high-altitude adaptation (HAA), yet most of them are located in non-coding genomic regions, leaving their specific functions and underlying mechanisms largely unknown. In this study, we analyze whole-genome and transcriptome sequencing data from a self-established cohort comprising 61 native highlanders (NHs) and 164 acclimatized newcomers (ANs), identifying 6,586 cis- and 34,203 trans-expression quantitative trait loci (eQTLs), along with 130 cell type-specific eQTLs. By further combining these data with a large East Asia (~30% Tibetan) genome-wide association study (GWAS) cohort, we employ colocalization and causal inference analyses to prioritize 85 cis-eQTLs associated with HAA and identify several novel candidate causal genes, including EXOC8, which is experimentally confirmed to regulate erythroid differentiation. Additionally, network analysis of these causal genes uncovers multiple regulatory pathways, mainly involving energy metabolism, autophagy, ubiquitination and inflammation. Our study offers a comprehensive eQTL map and reveals causal chains of "variant-gene-phenotype" for HAA-related traits, which provides new insights into potential regulatory mechanisms and targets for prevention and treatment of altitude sickness.
Quantitative Trait Loci↗
Transcriptome analysis of Escherichia coli using high-density oligonucleotide probe arrays.
Microarrays traditionally have been used to analyze the expression behavior of large numbers of coding transcripts. Here we present a comprehensive approach for high-throughput transcript discovery in Escherichia coli focused mainly on intergenic regions which, together with analysis of coding transcripts, provides us with a more complete insight into the organism's transcriptome. Using a whole genome array, we detected expression for 4052 coding transcripts and identified 1102 additional transcripts in the intergenic regions of the E.coli genome. Further classification reveals 317 novel transcripts with unknown function. Our results show that, despite sophisticated approaches to genome annotation, many cellular transcripts remain unidentified. Through the experimental identification of all RNAs expressed under a specific condition, we gain a more thorough understanding of all cellular processes.
3' Untranslated Regions↗
A ferroxidation/permeation iron uptake system is required for virulence in Ustilago maydis.
In the smut fungus Ustilago maydis, a tightly regulated cAMP signaling cascade is necessary for pathogenic development. Transcriptome analysis using whole genome microarrays set up to identify putative target genes of the protein kinase A catalytic subunit Adr1 revealed nine genes with putative functions in two high-affinity iron uptake systems. These genes locate to three gene clusters on different chromosomes and include the previously identified complementing siderophore auxotroph genes sid1 and sid2 involved in siderophore biosynthesis. Transcription of all nine genes plus three additional genes associated with the gene clusters was also coregulated by iron through the Urbs1 transcription factor. Two components of a high-affinity iron uptake system were characterized in more detail: fer2, encoding a high-affinity iron permease; and fer1, encoding an iron multicopper oxidase. Fer2 localized to the plasma membrane and complemented an ftr1 mutant of Saccharomyces cerevisiae lacking a high-affinity iron permease. During pathogenic development, fer2 expression was confined to the phase of hyphal proliferation inside the plant. fer2 as well as fer1 deletion mutants were strongly affected in virulence. These data highlight the importance of the high-affinity iron uptake system via an iron permease and a multicopper oxidase for biotrophic development in the U. maydis/maize (Zea mays) pathosystem.
Biological Transport↗
Phylogenomic evidence provides insights into the phylogeny and speciation patterns in the subgenus Caloscordum (Allium, Amaryllidaceae).
Phylogenomics with abundant informative sites offers a powerful means for elucidating complex diversification history. Here, we collected 22 samples from 18 populations representing all species of subgenus Caloscordum (Allium). Using transcriptome and whole-genome resequencing data, we generated 1755 low-copy nuclear genes and 81 plastid genes. By integrating morphological and phylogenomic evidence, we clarified the subgenus's complex evolutionary histories and speciation patterns. A total of 18 morphological characteristics were analysed, with a taxonomic framework established. Our analyses resolved robust species relationships despite detecting extensive phylogenetic discordances, which were attributed to incomplete lineage sorting (ILS) and hybridization. Specifically, our results suggest that A. inutile originated via rapid budding speciation from the widespread A. tubiflorum. This process likely coincided with mid-Pleistocene glacial-interglacial cycles and may have been reinforced by geographic isolation and ecological adaptation. In contrast, the sole tetraploid species, A. peikingense, was confirmed to be of hybrid origin, derived from A. neriniflorum and A. tubiflorum. This allopolyploidization event appears to have been facilitated by secondary contact between the parent species, which was likely associated with climatic oscillations within the 35° N-45° N arid belt. Overall, our findings elucidate the intricate speciation patterns within Caloscordum and highlight how the interplay of polyploidization, ecological isolation, and tectonic uplift-driven aridification has shaped plant diversity in East Asia.
Phylogeny↗
Comprehensive Multiplatform Tyrosine Kinase Profiling Reveals Novel Actionable FGFR Aberrations across Sarcomas Affecting the Young.
Limited targeted agents are approved for pediatric sarcomas. Tyrosine kinase (TK) inhibitors (TKi) have shown clinical efficacy in some, but not all, young patients with sarcoma. A major obstacle preventing further advances and clinical implementation is the lack of predictive response biomarkers to guide TK-targeted treatments. TK-activating fusions or mutations are rare in these patients. RNA overexpression of TKs is a frequent feature. The unresolved question is when upregulated TK expression is associated with kinase activation and signaling dependence. We explored the TK molecular landscape of 107 patients with sarcoma from the ZERO Childhood Cancer Precision Medicine Program (ZERO) using whole-genome and -transcriptome sequencing. Phosphoproteomic analyses of tyrosine phosphorylation (pY) and functional in vitro and in vivo assays were performed in cell lines and patient-derived xenografts (PDX). Our analysis shows that although novel genomic driver lesions are rare, when present they are therapeutically actionable as exemplified by a novel LSM1-FGFR1 fusion identified in a patient with osteosarcoma. We further show that in certain contexts, TK RNA expression can indicate TK pathway activity and predict TKi sensitivity. We highlight the utility of FGFR inhibitors in PAX3-FOXO1 fusion-positive rhabdomyosarcomas (FP-RMS) characterized by high FGFR4 and FGF8 RNA expression levels and FGFR4 activation (FGFR4_pY). We demonstrate marked tumor growth inhibition in all FP-RMS PDXs treated with single-agent FGF401 (FGFR4-specific inhibitor) and single-agent lenvatinib (multikinase FGFR inhibitor) and report a clinical response to lenvatinib in a patient with relapsed metastatic FP-RMS. Altogether, we identified new patients with sarcoma who may benefit from FGFR inhibitors, most notably FP-RMS via FGFR4/FGF8 coexpression.
Journal Article↗
Intestinal organoid screen reveals that Bacillus velezensis PGM541 promotes epithelial proliferation via its metabolite butyric acid.
BACKGROUND: Probiotics have been widely used for the regulation of intestinal health. Current screening methods for probiotics typically rely on animal or two-dimensional cell models. In this study, we employed intestinal organoids to identify a candidate probiotic strain. Furthermore, we investigated the potential mechanisms through which this strain and its active metabolites exert their effects, thereby evaluating the efficacy of this screening approach. RESULTS: Firstly, candidate probiotic strain PGM541 was identified from a porcine-derived Bacillus library by assessing organoid viability. Subsequently, to validate the organoid screening reliability, the potential mechanism of strain PGM541 on the intestinal epithelium was investigated; it was found to exhibit probiotic functions by regulating cell proliferation in both in vitro organoid and in vivo piglet models. Furthermore, organoid screening combined with metabolomic analysis identified butyric acid (BA) as the key bioactive metabolite responsible for driving epithelial proliferation. Whole-genome and transcriptomic analyses revealed the biosynthetic pathway of BA in strain PGM541. Importantly, BA receptor blockade experiments directly confirmed that BA enhances epithelial proliferation via interaction with the FFAR2 receptor, thereby validating its functional activity. Additionally, strain PGM541 exhibited protective effects against dextran sulfate sodium (DSS)-induced colitis, further validating the effectiveness of the intestinal organoid platform for probiotic screening. CONCLUSIONS: The probiotic strain PGM541, which was screened using intestinal organoids, promotes intestinal epithelial cell proliferation via its metabolite BA activating the FFAR2 receptor. These findings demonstrate that the intestinal organoid model serves as an effective platform for both preliminary probiotic screening and mechanistic investigation. Video Abstract.
Animals↗
Expression genomics and cancer biology.
Expression genomics is a term that is used to describe the investigation of transcription in a whole-genome manner and includes the investigation of gene regulation. Characteristic of this approach is its comprehensiveness and the highly multiplexed nature of its analysis. Thus, the range of technologies used include microarrays, tag library approaches, such as serial analysis of gene expression (SAGE), full-length cDNA cloning and sequencing, and chromatin immunoprecipitation coupled with cloning/sequencing or applied to genomic chips. These technologies are all complementary since they have different capabilities and attack different components of the transcriptome: transcriptional regulation, promoter usage, differential splicing, and gene expression. Unlike genome sequencing, the combinatorial complexity of the transcriptome is immense, making its complete characterization impossible. Instead, the strategy has shifted to the analysis of the whole transcriptome in a context-driven, cell biological framework where the fundamental truths emerge through multiple comparisons and pharmacological challenges. The density of non-redundant data generated with any experiment allows for the assessment of higher order relationships. This comprehensive data, in turn, permits information convergence across different experiments, organisms, and data sets. Surprising concordance in the underlying conclusions is observed with data of such complexity. Since microarrays have been the most widely used technology in expression genomics for the study of cancer biology, this paper will focus on studies using expression arrays, but will also touch on other transcriptome-directed technologies. The experience with these approaches is sufficiently mature to arrive at some generalizable observations. First, although expression genomics is a useful approach for the discovery of individual candidate genes, its greatest power is in defining class distinctions using the collective behavior of gene clusters. Therefore, expression genomic output can effectively uncover hierarchies of molecular importance. Second, in the hierarchy of factors that determine the expression footprint within a cell, cell lineage is the most important, followed by the activity of specific biochemical pathways and further followed by the effect of individual genes. Lastly, expression profiling is an effective clinical tool that can discern prognostic and therapeutic classes. The importance of these gene lists is that not only do they describe potential therapeutic targets, but they are effective monitors of therapeutic efficacy.
Animals↗