Genome-wide Gene Expression Research Articles

Genome-wide characterization and expression of DELLA genes in Cucurbita moschata reveal their potential roles under development and abiotic stress.

DELLA gene family plays a key role in regulating plant development and responding to stress. Currently, many DELLA family members have been identified in plants, however, information on DELLA genes in pumpkin (Cucurbita moschata) is scarce. In this study, physical and chemical properties, gene structure cis-regulatory elements and expression of CmoDELLA genes were examined in pumpkin. We found that seven CmoDELLA genes were identified in pumpkin, and they were unevenly classified into five chromosomes. CmoDELLA proteins were relatively unstable and their secondary structures were mainly made up α-helix and random coil. All seven CmoDELLA proteins contained typical DELLA domain and GRAS domain, however, motif numbers between CmoDELLA proteins were unevenly distributed, implying the complex evolution and functional diversification of CmoDELLA proteins. Cis-regulatory elements analysis revealed that CmoDELLA genes might play an essential role in regulating plant growth and development, and response to stress in pumpkin. Transcriptome data in the roots, stems, leaves and fruits demonstrated that CmoDELLA2, CmoDELLA3 and CmoDELLA7 were related to the stems development, CmoDELLA1, CmoDELLA4, CmoDELLA5 and CmoDELLA6 were associated with the fruits development. Furthermore, we found that CmoDELLA1 and CmoDELLA5 were up-regulated under NaCl stress. CmoDELLA1, CmoDELLA2, CmoDELLA3, CmoDELLA5, CmoDELLA6 and CmoDELLA7 were remarkably induced under waterlogging stress. While, all of the 7 CmoDELLA genes showed significantly induced expression under cold stress. The expression patterns under abiotic stress suggested that CmoDELLA genes might mediate the stress response of pumpkin to NaCl, waterlogging and cold, however, the functions of different CmoDELLA genes varied under different stress. Overall, our study provides valuable information for further research about the potential functions and regulatory networks of CmoDELLA genes in pumpkin.

Genome-Wide Characterization and Gene Expression Analyses of Malate Dehydrogenase (MDH) Genes in Low-Phosphorus Stress Tolerance of Chinese Fir (Cunninghamia lanceolata).

Malate dehydrogenase (MDH) genes play vital roles in developmental control and environmental stress tolerance in sessile plants by modulating the organic acid-malic acid level. However, MDH genes have not yet been characterized in gymnosperm, and their roles in nutrient deficiency are largely unexplored. In this study, 12 MDH genes were identified in Chinese fir (Cunninghamia lanceolata), namely, ClMDH-1, -2, -3, …, and -12. Chinese fir is one of the most abundant commercial timber trees in China, and low phosphorus has limited its growth and production due to the acidic soil of southern China. According to the phylogenetic analysis, MDH genes were classified into five groups, and Group 2 genes (ClMDH-7, -8, -9, and 10) were only found to be present in Chinese fir but not in Arabidopsis thaliana and Populus trichocarpa. In particular, the Group 2 MDHs also had specific functional domains-Ldh_1_N (malidase NAD-binding functional domain) and Ldh_1_C (malate enzyme C-terminal functional domain)-indicating a specific function of ClMDHs in the accumulation of malate. All ClMDH genes contained the conserved MDH gene characteristic functional domains Ldh_1_N and Ldh_1_C, and all ClMDH proteins exhibited similar structures. Twelve ClMDH genes were identified from eight chromosomes, involving fifteen ClMDH homologous gene pairs, each with a Ka/Ks ratio of <1. The analysis of cis-elements, protein interactions, and transcription factor interactions of MDHs showed that the ClMDH gene might play a role in plant growth and development, and in response to stress mechanisms. The results of transcriptome data and qRT-PCR validation based on low-phosphorus stress showed that ClMDH1, ClMDH6, ClMDH7, ClMDH2, ClMDH4, ClMDH5, ClMDH10 and ClMDH11 were upregulated under low-phosphorus stress and played a role in the response of fir to low-phosphorus stress. In conclusion, these findings lay a foundation for further improving the genetic mechanism of the ClMDH gene family in response to low-phosphorus stress, exploring the potential function of this gene, promoting the improvement of fir genetics and breeding, and improving production efficiency.

Whole genome methylation combined with RNA-seq reveals the protective effects of Gualou-Xiebai herb pair in foam cells through DNA methylation mediated PI3K-AKT signaling pathway.

DNA methylation, including aberrant hypomethylation and hypermethylation, plays a significant role in atherosclerosis (AS); therefore, targeting the unbalanced methylation in AS is a potential treatment strategy. Gualou-xiebai herb pair (GXHP), a classic herb combination, have been used for the treatment of atherosclerotic-associated diseases in traditional Chinese medicine. However, the effects and underlying mechanism of GXHP on AS remain nebulous. In this study, the CCK-8 method was applied to determine the non-toxic treatment concentrations for GXHP. The formation of foam cells played a critical role in AS, so the foam cells model was established after RAW264.7 cells were treated with ox-LDL. The contents of total cholesterol (TC) and free cholesterol (FC) were determined by Gas chromatography-mass spectrometry (GC-MS). Enzyme-linked immunosorbent assay (ELISA) was used to check the expressions of inflammatory factors including IL-1β, TNF-α, and VCAM-1. Methyl-capture sequencing (MC-seq) and RNA-seq were applied to observe the changes in genome-wide DNA methylation and gene expression, respectively. Kyoto Encyclopedia of Genes and Genomes (KEGG) were performed to analyze differentially methylated genes (DMGs) and differentially expressed genes (DEGs). The targeted signaling pathway was selected and verified using western blotting (WB). The results showed that the lipids and inflammatory factors in foam cells significantly increased. GXHP significantly reduced the expression of TC, FC, and inflammatory factors. MC-seq and RNA-seq showed that GXHP not only corrected the aberrant DNA hypermethylation, but also DNA hypomethylation, thus restored the aberrant DEGs in foam cells induced by ox-LDL. GXHP treatment may target the PI3K-Akt signaling pathway. GXHP reduced the protein levels of phosphorylated(p)-PI3K and p-AKT in foam cells. Our data suggest that treatment with GXHP showed protective effects against AS through the inhibition of DNA methylation mediated PI3K-AKT signaling pathway, suggesting GXHP as a novel methylation-based agent.

The global regulator FpLaeB is required for the regulation of growth, development, and virulence in Fusarium pseudograminearum.

Fusarium pseudograminearum is a soil-borne pathogen that is capable of causing a highly destructive crown disease in wheat. Secondary metabolites (SMs), especially deoxynivalenol (DON), are the primary virulence factors during infection. Here, we characterised the global regulator FpLaeB, an orthologue of LaeB protein function, to regulate the SM in Aspergillus nidulans. Through the utility of the gene targeting approach, we found that the vegetative growth of the FpLaeB deletion mutant was drastically reduced compared to that of the wild type. FpLaeB was also important for conidiation because the FpLaeB deletion mutant formed fewer conidia in induced medium. In addition, the sensitivity of the FpLaeB deletion mutant to the cell wall integrity inhibitor was decreased, while its growth was more severely inhibited by the cell membrane inhibitor sodium dodecyl sulfate (SDS) than that of the wild type. More importantly, the virulence was decreased when the FpLaeB deletion mutant was inoculated onto the wheat stem base or head. Through genome-wide gene expression profiling, FpLaeB was found to regulate several processes related to the above phenotypes such as the carbohydrate metabolic process, which is an integral and intrinsic component of membranes, especially SMs. Furthermore, the generation of DON was impaired in the FpLaeB deletion mutant via ultraperformance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) assay. These results showed that FpLaeB plays an important role in the growth, development, and maintenance of the cell wall, and in membrane integrity. More importantly, FpLaeB is required for SMs and full virulence in F. pseudograminearum.

Distinct genome-wide DNA methylation and gene expression signatures in classical monocytes from African American patients with systemic sclerosis

BackgroundSystemic sclerosis (SSc) is a multisystem autoimmune disorder that has an unclear etiology and disproportionately affects women and African Americans. Despite this, African Americans are dramatically underrepresented in SSc research. Additionally, monocytes show heightened activation in SSc and in African Americans relative to European Americans. In this study, we sought to investigate DNA methylation and gene expression patterns in classical monocytes in a health disparity population.MethodsClassical monocytes (CD14+ + CD16−) were FACS-isolated from 34 self-reported African American women. Samples from 12 SSc patients and 12 healthy controls were hybridized on MethylationEPIC BeadChip array, while RNA-seq was performed on 16 SSc patients and 18 healthy controls. Analyses were computed to identify differentially methylated CpGs (DMCs), differentially expressed genes (DEGs), and CpGs associated with changes in gene expression (eQTM analysis).ResultsWe observed modest DNA methylation and gene expression differences between cases and controls. The genes harboring the top DMCs, the top DEGs, as well as the top eQTM loci were enriched for metabolic processes. Genes involved in immune processes and pathways showed a weak upregulation in the transcriptomic analysis. While many genes were newly identified, several other have been previously reported as differentially methylated or expressed in different blood cells from patients with SSc, supporting for their potential dysregulation in SSc.ConclusionsWhile contrasting with results found in other blood cell types in largely European-descent groups, the results of this study support that variation in DNA methylation and gene expression exists among different cell types and individuals of different genetic, clinical, social, and environmental backgrounds. This finding supports the importance of including diverse, well-characterized patients to understand the different roles of DNA methylation and gene expression variability in the dysregulation of classical monocytes in diverse populations, which might help explaining the health disparities.

Genome-Wide Gene Expression Profiling Reveals the Direct Effect of Dienogest on Ovarian Endometriotic Stromal Cells

Endometriosis affects up to 10% of women of reproductive age, causing dysmenorrhea, chronic pelvic pain, and infertility. The current key drug for endometriosis is dienogest, a progestin with high specificity for the progesterone receptor. To reveal the direct anti-endometriotic effect of dienogest on ovarian endometriotic cells, we investigated the genome-wide gene expression profiles of ovarian endometriotic stromal cells with (Dienogest group) or without dienogest treatment (Control group) and compared the groups’ gene expression profiles. We performed a gene ontology (GO) analysis and Ingenuity pathway analysis using these data. To validate the microarray data, we performed real-time RT-PCRs and immunohistochemistry for the differentially expressed genes between the two groups. Of 647 genes differentially expressed between the two groups, 314 genes were upregulated and 333 were downregulated in the Dienogest group versus the Control group. The GO analysis showed that the regulation of macrophage chemotaxis, the collagen catabolic process, and the proteoglycan biosynthetic process are the main biological processes closely associated with the differentially expressed genes. We identified 20 canonical pathways that were most significantly differentially expressed in the Dienogest group versus the Control group. We observed that matrix metalloproteinases (MMPs) are the genes in these pathways that are most closely associated with dienogest treatment. Of components involved in the regulation of macrophage chemotaxis, colony-stimulating factor 1 and macrophage-stimulating 1 are potential upstream regulators of MMPs and were observed herein to be suppressed by dienogest. Our results suggest that dienogest may thus exert its anti-endometriotic effect by directly suppressing MMPs.

A Systems Biology Approach To Disentangle the Direct and Indirect Effects of Global Transcription Factors on Gene Expression in Escherichia coli.

Delineating the pleiotropic effects of global transcriptional factors (TFs) is critical for understanding the system-wide regulatory response in a particular environment. Currently, with the availability of genome-wide TF binding and gene expression data for Escherichia coli, several gene targets can be assigned to the global TFs, albeit inconsistently. Here, using a systematic integrated approach with emphasis on metabolism, we characterized and quantified the direct effects as well as the growth rate-mediated indirect effects of global TFs using deletion mutants of FNR, ArcA, and IHF regulators (focal TFs) under glucose fermentative conditions. This categorization enabled us to disentangle the dense connections seen within the transcriptional regulatory network (TRN) and determine the exact nature of focal TF-driven epistatic interactions with other global and pathway-specific local regulators (iTFs). We extended our analysis to combinatorial deletions of these focal TFs to determine their cross talk effects as well as conserved patterns of regulatory interactions. Moreover, we predicted with high confidence several novel metabolite-iTF interactions using inferred iTF activity changes arising from the allosteric effects of the intracellular metabolites perturbed as a result of the absence of focal TFs. Further, using compendium level computational analyses, we revealed not only the coexpressed genes regulated by these focal TFs but also the coordination of the direct and indirect target expression in the context of the economy of intracellular metabolites. Overall, this study leverages the fundamentals of TF-driven regulation, which could serve as a better template for deciphering mechanisms underlying complex phenotypes. IMPORTANCE Understanding the pleiotropic effects of global TFs on gene expression and their relevance underlying a specific response in a particular environment has been challenging. Here, we distinguish the TF-driven direct effects and growth rate-mediated indirect effects on gene expression using single- and double-deletion mutants of FNR, ArcA, and IHF regulators under anaerobic glucose fermentation. Such dissection assists us in unraveling the precise nature of interactions existing between the focal TF(s) and several other TFs, including those altered by allosteric effects of intracellular metabolites. We were able to recapitulate the previously known metabolite-TF interactions and predict novel interactions with high confidence. Furthermore, we determined that the direct and indirect gene expression have a strong connection with each other when analyzed using the coexpressed- or coregulated-gene approach. Deciphering such regulatory patterns explicitly from the metabolism point of view would be valuable in understanding other unpredicted complex regulation existing in nature.

Location of a topologically associating domain at the nuclear periphery has no systematic causal effect on its genes transcription levels in drosophila nuclei.

Several studies have demonstrated a correlation between expression of genes and their positioning at the nuclear periphery. However, no systematic genome-wide analysis of how the probability of location at the nuclear envelope (NE) affects gene expression is available. It is unclear whether there is a genome-wide correlation or causal relationship between the expression levels of groups of genes in topologically associating domains (TADs) of Drosophila nuclei and the probabilities of TADs to be found at the NE. To investigate the possible relationship, we have developed a coarse-grained dynamic model of the entire Drosophila melanogaster interphase nucleus that explicitly accounts for the different epigenetic classes of TADs and for the interactions between the NE and lamina-associated domains (LADs). The model predicts a highly dynamic positioning of LADs and TADs at the NE. The probability of a LAD-containing TAD to be found at the NE is determined by a highly variable local density of LADs along genome. Modeling of the lamin depleted nuclei predicts a significant reduction of TAD contacts with the NE and a substantial redistribution of the chromatin. We combine model derived probabilities of TADs to be found at the NE with the genome-wide experimental gene expression data for both wild type and lamin depleted nuclei. The analysis of the TAD averaged gene transcription levels against the probabilities of individual TADs to be at the NE suggests that, within statistical error margin, the stochastic positioning of Drosophila TADs at the NE does not, by itself, systematically affect the average level of gene expression in TADs. A weak anti-correlation exists between these expression levels and the probabilities of TADs to be found at the NE, but no causality.

Gene expression profiling of nasal inflammation induced by diesel particles using an in vivo system

Korean diesel particulate matter 20 (KDP20) is a pollutant comprising a complex mixture of carbon and chemical irritants. Although particulate matter and nasal inflammation are strongly associated, the underlying molecular mechanism based on systematic transcriptome analysis remains unknown. In this study, genome-wide gene expression profiles of mouse nasal tissues were determined following exposure to KDP20 for 5 and 10 days and compared with those of the control (n = 4/group). We identified 758 significant differentially expressed genes (DEGs) and classified them as 5-day-specific, 10-day-specific, and common among groups based on their expression patterns. The terms “regulation of alpha-beta T cell differentiation,” “macrophage differentiation,” and “cell adhesion mediated by integrin” were significantly enriched in each group. Receiver operating characteristic analysis revealed six genes as potential predictive biomarkers. The differential expression of these six genes was validated using quantitative RT-PCR (n = 3/group). Furthermore, a possible mechanism for nasal inflammation was suggested through the binding analysis between metal ions and genes. The genes identified in this study may play important roles in regulating the mechanism of nasal inflammation induced by diesel particles, especially immune cell regulation, and may function as markers for diesel particle-induced nasal inflammation.

Genome-Wide Gene Expression Analyses of the AtfA/AtfB-Mediated Menadione Stress Response in Aspergillus nidulans.

The bZIP transcription factors (TFs) govern regulation of development, secondary metabolism, and various stress responses in filamentous fungi. In this work, we carried out genome-wide expression studies employing Illumina RNAseq to understand the roles of the two bZIP transcription factors AtfA and AtfB in Aspergillus nidulans. Comparative analyses of transcriptomes of control, ΔatfA, ΔatfB, and ΔatfAΔatfB mutant strains were performed. Dependence of a gene on AtfA (AtfB) was decided by its differential downregulation both between the reference and ΔatfA (ΔatfB) strains and between the ΔatfB (ΔatfA) and the ΔatfAΔatfB strains in vegetatively grown cells (mycelia) and asexual spores (conidia) of menadione sodium bisulfite (MSB)-treated or untreated cultures. As AtfA is the primary bZIP TF governing stress-response in A. nidulans, the number of differentially expressed genes for ΔatfA was significantly higher than for ΔatfB in both mycelial and conidial samples, and most of the AtfB-dependent genes showed AtfA dependence, too. Moreover, the low number of genes depending on AtfB but not on AtfA can be a consequence of ΔatfA leading to downregulation of atfB expression. Conidial samples showed much higher abundance of atfA and atfB mRNAs and more AtfA- and AtfB-affected genes than mycelial samples. In the presence of MSB, the number of AtfB- (but not of AtfA-) affected genes decreased markedly, which was accompanied with decreased mRNA levels of atfB in MSB-treated mycelial (reference strain) and conidial (ΔatfA mutant) samples. In mycelia, the overlap between the AtfA-dependent genes in MSB-treated and in untreated samples was low, demonstrating that distinct genes can be under AtfA control under different conditions. Carbohydrate metabolism genes were enriched in the set of AtfA-dependent genes. Among them, AtfA-dependence of glycolytic genes in conidial samples was the most notable. Levels of transcripts of certain secondary metabolitic gene clusters, such as the Emericellamide cluster, also showed AtfA-dependent regulation. Genes encoding catalase and histidine-containing phosphotransfer proteins showed AtfA-dependence under all experimental conditions. There were 23 AtfB-dependent genes that did not depend on AtfA under any of our experimental conditions. These included a putative α-glucosidase (agdB), a putative α-amylase, calA, which is involved in early conidial germination, and an alternative oxidase. In summary, in A. nidulans there is a complex interaction between the two bZIP transcription factors, where AtfA plays the primary regulatory role.

Arabidopsis AGAMOUS-LIKE16 and SUPPRESSOR OF CONSTANS1 regulate the genome-wide expression and flowering time.

Flowering transition is tightly coordinated by complex gene regulatory networks, in which AGAMOUS-LIKE 16 (AGL16) plays important roles. Here, we identified the molecular function and binding properties of AGL16 and demonstrated its partial dependency on the SUPPRESSOR OF CONSTANS 1 (SOC1) function in regulating flowering. AGL16 bound to promoters of more than 2,000 genes via CArG-box motifs with high similarity to that of SOC1 in Arabidopsis (Arabidopsis thaliana). Approximately 70 flowering genes involved in multiple pathways were potential targets of AGL16. AGL16 formed a protein complex with SOC1 and shared a common set of targets. Intriguingly, only a limited number of genes were differentially expressed in the agl16-1 loss-of-function mutant. However, in the soc1-2 knockout background, AGL16 repressed and activated the expression of 375 and 182 genes, respectively, with more than a quarter bound by AGL16. Corroborating these findings, AGL16 repressed the flowering time more strongly in soc1-2 than in the Col-0 background. These data identify a partial inter-dependency between AGL16 and SOC1 in regulating genome-wide gene expression and flowering time, while AGL16 provides a feedback regulation on SOC1 expression. Our study sheds light on the complex background dependency of AGL16 in flowering regulation, thus providing additional insights into the molecular coordination of development and environmental adaptation.

A temporal in vivo catalog of chromatin accessibility and expression profiles in pineoblastoma reveals a prevalent role for repressor elements.

Pediatric pineoblastomas (PBs) are rare and aggressive tumors of grade IV histology. Although some oncogenic drivers are characterized, including germline mutations in RB1 and DICER1, the role of epigenetic deregulation and cis-regulatory regions in PB pathogenesis and progression is largely unknown. Here, we generated genome-wide gene expression, chromatin accessibility, and H3K27ac profiles covering key time points of PB initiation and progression from pineal tissues of a mouse model of CCND1-driven PB. We identified PB-specific enhancers and super-enhancers, and found that in some cases, the accessible genome dynamics precede transcriptomic changes, a characteristic that is underexplored in tumor progression. During progression of PB, newly acquired open chromatin regions lacking H3K27ac signal become enriched for repressive state elements and harbor motifs of repressor transcription factors like HINFP, GLI2, and YY1. Copy number variant analysis identified deletion events specific to the tumorigenic stage, affecting, among others, the histone gene cluster and Gas1, the growth arrest specific gene. Gene set enrichment analysis and gene expression signatures positioned the model used here close to human PB samples, showing the potential of our findings for exploring new avenues in PB management and therapy. Overall, this study reports the first temporal and in vivo cis-regulatory, expression, and accessibility maps in PB.

Genomic and epigenomic responses to aspirin in human colonic organoids.

Aspirin (ASA) is a proven chemoprotective agent for colorectal cancer, though mechanisms underlying these effects are incompletely understood. Human organoids are an ideal system to study genomic and epigenomic host-environment interactions. We use human colonic organoids to profile ASA responses on genome-wide gene expression and chromatin accessibility. Human colonic organoids from one individual were cultured and treated in triplicate with 3 mM ASA or vehicle control (DMSO) for 24 h. Gene expression and chromatin accessibility were measured using RNA- and ATAC-sequencing, respectively. Differentially expressed genes were analyzed using DESeq2. Top genes were validated by qPCR. Gene set enrichment was performed by SetRank. Differentially accessible peaks were analyzed using DiffBind and edgeR. Peak annotation and differential transcription factor motifs were determined by HOMER and diffTF. The results showed robust transcriptional responses to ASA with significant enrichment for fatty acid oxidation and peroxisome proliferator-activated receptor (PPAR) signaling that were validated in independent organoid lines. A large number of differentially accessible chromatin regions were found in response to ASA with significant enrichment for Fos, Jun, and Hnf transcription factor motifs. Integrated analysis of epigenomic and genomic treatment responses highlighted gene regions that could mediate ASA's specific effects in the colon including those involved in chemoprotection and/or toxicity. Assessment of chromatin accessibility and transcriptional responses to ASA yielded new observations about genome-wide effects in the colon facilitated by application of human colonic organoids. This framework can be applied to study colonic ASA responses between individuals and populations in future studies.

Vitamin C boosts DNA demethylation in TET2 germline mutation carriers

BackgroundAccurate regulation of DNA methylation is necessary for normal cells to differentiate, develop and function. TET2 catalyzes stepwise DNA demethylation in hematopoietic cells. Mutations in the TET2 gene predispose to hematological malignancies by causing DNA methylation overload and aberrant epigenomic landscape. Studies on mice and cell lines show that the function of TET2 is boosted by vitamin C. Thus, by strengthening the demethylation activity of TET2, vitamin C could play a role in the prevention of hematological malignancies in individuals with TET2 dysfunction. We recently identified a family with lymphoma predisposition where a heterozygous truncating germline mutation in TET2 segregated with nodular lymphocyte-predominant Hodgkin lymphoma. The mutation carriers displayed a hypermethylation pattern that was absent in the family members without the mutation.MethodsIn a clinical trial of 1 year, we investigated the effects of oral 1 g/day vitamin C supplementation on DNA methylation by analyzing genome-wide DNA methylation and gene expression patterns from the family members.ResultsWe show that vitamin C reinforces the DNA demethylation cascade, reduces the proportion of hypermethylated loci and diminishes gene expression differences between TET2 mutation carriers and control individuals.ConclusionsThese results suggest that vitamin C supplementation increases DNA methylation turnover and provide a basis for further work to examine the potential benefits of vitamin C supplementation in individuals with germline and somatic TET2 mutations.Trial registration: This trial was registered at EudraCT with reference number of 2018-000155-41 (01.04.2019).Graphical

IRF8 Regulates Intrinsic Ferroptosis through Repressing p53 Expression to Maintain Tumor Cell Sensitivity to Cytotoxic T Lymphocytes.

Ferroptosis has emerged as a cytotoxic T lymphocyte (CTL)-induced tumor cell death pathway. The regulation of tumor cell sensitivity to ferroptosis is incompletely understood. Here, we report that interferon regulatory factor 8 (IRF8) functions as a regulator of tumor cell intrinsic ferroptosis. Genome-wide gene expression profiling identified the ferroptosis pathway as an IRF8-regulated pathway in tumor cells. IRF8.KO tumor cells acquire resistance to intrinsic ferroptosis induction and IRF8-deficient tumor cells also exhibit decreased ferroptosis in response to tumor-specific CTLs. Irf8 deletion increased p53 expression in tumor cells and knocking out p53 in IRF8.KO tumor cells restored tumor cell sensitivity to intrinsic ferroptosis induction. Furthermore, IRF8.KO tumor cells grew significantly faster than WT tumor cells in immune-competent mice. To restore IRF8 expression in tumor cells, we designed and synthesized codon usage-optimized IRF8-encoding DNA to generate IRF8-encoding plasmid NTC9385R-mIRF8. Restoring IRF8 expression via a lipid nanoparticle-encapsulated NTC9385R-mIRF8 plasmid therapy suppressed established tumor growth in vivo. In human cancer patients, nivolumab responders have a significantly higher IRF8 expression level in their tumor cells as compared to the non-responders. Our data determine that IRF8 represses p53 expression to maintain tumor cell sensitivity to intrinsic ferroptosis.

Allele-specific expression analysis for complex genetic phenotypes applied to a unique dilated cardiomyopathy cohort

Allele-specific expression (ASE) analysis detects the relative abundance of alleles at heterozygous loci as a proxy for cis-regulatory variation, which affects the personal transcriptome and proteome. This study describes the development and application of an ASE analysis pipeline on a unique cohort of 87 well phenotyped and RNA sequenced patients from the Maastricht Cardiomyopathy Registry with dilated cardiomyopathy (DCM), a complex genetic disorder with a remaining gap in explained heritability. Regulatory processes for which ASE is a proxy might explain this gap. We found an overrepresentation of known DCM-associated genes among the significant results across the cohort. In addition, we were able to find genes of interest that have not been associated with DCM through conventional methods such as genome-wide association or differential gene expression studies. The pipeline offers RNA sequencing data processing, individual and population level ASE analyses as well as group comparisons and several intuitive visualizations such as Manhattan plots and protein–protein interaction networks. With this pipeline, we found evidence supporting the case that cis-regulatory variation contributes to the phenotypic heterogeneity of DCM. Additionally, our results highlight that ASE analysis offers an additional layer to conventional genomic and transcriptomic analyses for candidate gene identification and biological insight.

Genome-wide identification, characterization and gene expression of BES1 transcription factor family in grapevine (Vitis vinifera L.)

BES1, as the most important transcription factor responsible for brassinolide (BR) signaling, has been confirmed to play a significant role in regulating plant growth and the improvement of stress resistance. The transcriptional regulatory mechanism of BES1 has been well elucidated in several plants, such as Arabidopsis thaliana (A. thaliana), Triticum aestivum L. (T. aestivum), and Oryza sativa L. (O. sativa). Nevertheless, the genome-wide analysis of the BES1 family in Vitis vinifera L. (V. vinifera). has not been comprehensively carried out. Thus, we have conducted a detailed analysis and identification of the BES1 transcription factors family in V. vinifera; a total of eight VvBES1 genes was predicted, and the phylogenetic relationships, gene structures, and Cis-acting element in their promoters were also analyzed. BES1 genes have been divided into three groups (I, II and III) based on phylogenetic relationship analysis, and most of VvBES1 genes were in group III. Also, we found that VvBES1 genes was located at seven of the total nineteen chromosomes, whereas VvBES1-2 (Vitvi04g01234) and VvBES1-5 (Vitvi18g00924) had a collinearity relationship, and their three copies are well preserved. In addition, the intron–exon model of VvBES1 genes were mostly conserved, and there existed several Cis-acting elements related to stress resistance responsive and phytohormones responsive in BES1s genes promoter. Moreover, the BES1 expressions were different in different V. vinifera organs, and BES1 expressions were different in different V. vinifera varieties under saline-alkali stress and heat stress, the expression of VvBES1 also changed with the prolongation of saline-alkali stress treatment time. The above findings could not only lay a primary foundation for the further validation of VvBES1 function, but could also provide a reference for molecular breeding in V. vinifera.

Identification of a Hypoxia-Related Signature as Candidate Detector for Schizophrenia Based on Genome-Wide Gene Expression

Introduction: Schizophrenia (SCZ), a severe neuropsychiatric disorder with high genetic susceptibility, has high rates of misdiagnosis due to the unavoidably subjective factors and heterogeneous clinical presentations. Hypoxia has been identified as an importantly risk factor that participates in the development of SCZ. Therefore, development of a hypoxia-related biomarker for SCZ diagnosis is promising. Therefore, we dedicated to develop a biomarker that could contribute to distinguishing healthy controls and SCZ patients. Methods: GSE17612, GSE21935, and GSE53987 datasets, consisting of 97 control samples and 99 SCZ samples, were involved in our study. The hypoxia score was calculated based on the single-sample gene-set enrichment analysis using the hypoxia-related differentially expressed genes to quantify the expression levels of these genes for each SCZ patient. Patients in high-score groups were defined if their hypoxia score was in the upper half of all hypoxia scores and patients in low-score groups if their hypoxia score was in the lower half. GSEA was applied to detect the functional pathway of these differently expressed genes. CIBERSORT algorithm was utilized to evaluate the tumor-infiltrating immune cells of SCZ patients. Results: In this study, we developed and validated a biomarker consisting of 12 hypoxia-related genes that could distinguish healthy controls and SCZ patients robustly. We found that the metabolism reprogramming might be activated in the patient with high hypoxia score. Finally, CIBERSORT analysis illustrated that lower composition of naive B cells and higher composition of memory B cells might be observed in low-score groups of SCZ patients. Conclusion: These findings revealed that the hypoxia-related signature was acceptable as a detector for SCZ, providing further insight into effective diagnosis and treatment strategies for SCZ.

Recent advances in prostate cancer: WNT signaling, chromatin regulation, and transcriptional coregulators.

Prostate cancer is one of the most common diseases in men worldwide. Surgery, radiation therapy, and hormonal therapy are effective treatments for early-stage prostate cancer. However, the development of castration-resistant prostate cancer has increased the mortality rate of prostate cancer. To develop novel drugs for castration-resistant prostate cancer, the molecular mechanisms of prostate cancer progression must be elucidated. Among the signaling pathways regulating prostate cancer development, recent studies have revealed the importance of noncanonical wingless-type MMTV integration site family (WNT) signaling pathways, mainly that involving WNT5A, in prostate cancer progression and metastasis; however, its role remains controversial. Moreover, chromatin remodelers such as the switch/sucrose nonfermentable (SWI/SNF) complex and chromodomain helicase DNA-binding proteins 1 also play important roles in prostate cancer progression through genome-wide gene expression changes. Here, we review the roles of noncanonical WNT signaling pathways, chromatin remodelers, and epigenetic enzymes in the development and progression of prostate cancer.

Abstract 1558: Decoding the regulation of genome-wide accessible chromatin and gene expression in the polyploid Camelina

Abstract 1558: Decoding the regulation of genome-wide accessible chromatin and gene expression in the polyploid Camelina