bZIP
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Lower risk (LR) myelodysplastic syndromes (MDS) are heterogeneous hematopoietic stem and progenitor disorders caused by the accumulation of somatic mutations in various genes including epigenetic regulators that may produce convergent DNA methylation patterns driving specific gene expression profiles. The integration of genomic, epigenomic, and transcriptomic profiling has the potential to spotlight distinct LR-MDS categories on the basis of pathophysiological mechanisms. We performed a comprehensive study of somatic mutations and DNA methylation in a large and clinically well-annotated cohort of treatment-naive patients with LR-MDS at diagnosis from the EUMDS registry (ClinicalTrials.gov.NCT00600860). Unsupervised clustering analyses identified six clusters based on genetic profiling that concentrate into four clusters on the basis of genome-wide methylation profiling with significant overlap between the two clustering modes. The four methylation clusters showed distinct clinical and genetic features and distinct methylation landscape. All clusters shared hypermethylated enhancers enriched in binding motifs for ETS and bZIP (C/EBP) transcription factor families, involved in the regulation of myeloid cell differentiation. By contrast, one cluster gathering patients with early leukemic evolution exhibited a specific pattern of hypermethylated promoters and, distinctly from other clusters, the upregulation of AP-1 complex members FOS/FOSL2 together with the absence of hypermethylation of their binding motif at target gene enhancers, which is of relevance for leukemic initiation. Among MDS patients with lower-risk IPSS-M, this cluster displayed a significantly inferior overall survival (p < 0.0001). Our study showed that genetic and DNA methylation features of LR-MDS at early stages may refine risk stratification, therefore offering the frame for a precocious therapeutic intervention.
- Publikační typ
- časopisecké články MeSH
During innate immune responses, myeloid differentiation primary response 88 (MyD88) functions as a critical signaling adaptor protein integrating stimuli from toll-like receptors (TLR) and the interleukin-1 receptor (IL-1R) family and translates them into specific cellular outcomes. In B cells, somatic mutations in MyD88 trigger oncogenic NF-κB signaling independent of receptor stimulation, which leads to the development of B-cell malignancies. However, the exact molecular mechanisms and downstream signaling targets remain unresolved. We established an inducible system to introduce MyD88 to lymphoma cell lines and performed transcriptomic analysis (RNA-seq) to identify genes differentially expressed by MyD88 bearing the L265P oncogenic mutation. We show that MyD88L265P activates NF-κB signaling and upregulates genes that might contribute to lymphomagenesis, including CD44, LGALS3 (coding Galectin-3), NFKBIZ (coding IkBƺ), and BATF. Moreover, we demonstrate that CD44 can serve as a marker of the activated B-cell (ABC) subtype of diffuse large B-cell lymphoma (DLBCL) and that CD44 expression is correlated with overall survival in DLBCL patients. Our results shed new light on the downstream outcomes of MyD88L265P oncogenic signaling that might be involved in cellular transformation and provide novel therapeutical targets.
- MeSH
- adaptorové proteiny signální transdukční metabolismus MeSH
- antigeny CD44 genetika metabolismus MeSH
- difúzní velkobuněčný B-lymfom * patologie MeSH
- galektin 3 metabolismus MeSH
- lidé MeSH
- mutace MeSH
- myeloidní diferenciační faktor 88 genetika metabolismus MeSH
- NF-kappa B * genetika metabolismus MeSH
- stanovení celkové genové exprese MeSH
- transkripční faktory bZIP genetika MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
Oxidative stress is associated with cardiovascular and neurodegenerative diseases, diabetes, cancer, psychiatric disorders and aging. In order to counteract, eliminate and/or adapt to the sources of stress, cells possess elaborate stress-response mechanisms, which also operate at the level of regulating transcription. Interestingly, it is becoming apparent that the metabolic state of the cell and certain metabolites can directly control the epigenetic information and gene expression. In the fission yeast Schizosaccharomyces pombe, the conserved Sty1 stress-activated protein kinase cascade is the main pathway responding to most types of stresses, and regulates the transcription of hundreds of genes via the Atf1 transcription factor. Here we report that fission yeast cells defective in fatty acid synthesis (cbf11, mga2 and ACC/cut6 mutants; FAS inhibition) show increased expression of a subset of stress-response genes. This altered gene expression depends on Sty1-Atf1, the Pap1 transcription factor, and the Gcn5 and Mst1 histone acetyltransferases, is associated with increased acetylation of histone H3 at lysine 9 in the corresponding gene promoters, and results in increased cellular resistance to oxidative stress. We propose that changes in lipid metabolism can regulate the chromatin and transcription of specific stress-response genes, which in turn might help cells to maintain redox homeostasis.
- MeSH
- acetyltransferasy genetika MeSH
- chromatin * metabolismus MeSH
- exprese genu MeSH
- fosforylace MeSH
- metabolismus lipidů * MeSH
- mitogenem aktivované proteinkinasy metabolismus MeSH
- oxidační stres * MeSH
- regulace genové exprese u hub MeSH
- Schizosaccharomyces pombe - proteiny * genetika MeSH
- Schizosaccharomyces * genetika MeSH
- transkripční faktory bZIP genetika MeSH
- transkripční faktory genetika MeSH
- Publikační typ
- časopisecké články MeSH
Anaplastic large cell lymphoma (ALCL), an aggressive CD30-positive T-cell lymphoma, comprises systemic anaplastic lymphoma kinase (ALK)-positive, and ALK-negative, primary cutaneous and breast implant-associated ALCL. Prognosis of some ALCL subgroups is still unsatisfactory, and already in second line effective treatment options are lacking. To identify genes defining ALCL cell state and dependencies, we here characterize super-enhancer regions by genome-wide H3K27ac ChIP-seq. In addition to known ALCL key regulators, the AP-1-member BATF3 and IL-2 receptor (IL2R)-components are among the top hits. Specific and high-level IL2R expression in ALCL correlates with BATF3 expression. Confirming a regulatory link, IL-2R-expression decreases following BATF3 knockout, and BATF3 is recruited to IL2R regulatory regions. Functionally, IL-2, IL-15 and Neo-2/15, a hyper-stable IL-2/IL-15 mimic, accelerate ALCL growth and activate STAT1, STAT5 and ERK1/2. In line, strong IL-2Rα-expression in ALCL patients is linked to more aggressive clinical presentation. Finally, an IL-2Rα-targeting antibody-drug conjugate efficiently kills ALCL cells in vitro and in vivo. Our results highlight the importance of the BATF3/IL-2R-module for ALCL biology and identify IL-2Rα-targeting as a promising treatment strategy for ALCL.
- MeSH
- anaplastický velkobuněčný lymfom farmakoterapie genetika metabolismus patologie MeSH
- antigen Ki-1 genetika metabolismus MeSH
- imunokonjugáty farmakologie MeSH
- interleukin-15 farmakologie MeSH
- interleukin-2 farmakologie MeSH
- lidé MeSH
- myši MeSH
- nádorové buněčné linie MeSH
- proliferace buněk účinky léků MeSH
- receptor interleukinu-2 - alfa-podjednotka genetika imunologie metabolismus MeSH
- receptory interleukinu-2 genetika imunologie metabolismus MeSH
- regulace genové exprese u nádorů MeSH
- regulační oblasti nukleových kyselin MeSH
- represorové proteiny genetika metabolismus MeSH
- signální transdukce účinky léků MeSH
- transkripční faktory bZIP genetika metabolismus MeSH
- viabilita buněk účinky léků MeSH
- xenogenní modely - testy protinádorové aktivity MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Translation reinitiation is a gene-specific translational control mechanism. It is characterized by the ability of short upstream ORFs to prevent full ribosomal recycling and allow the post-termination 40S subunit to resume traversing downstream for the next initiation event. It is well known that variable transcript-specific features of various uORFs and their prospective interactions with initiation factors lend them an unequivocal regulatory potential. Here, we investigated the proposed role of the major initiation scaffold protein eIF4G in reinitiation and its prospective interactions with uORF's cis-acting features in yeast. In analogy to the eIF3 complex, we found that eIF4G and eIF4A but not eIF4E (all constituting the eIF4F complex) are preferentially retained on ribosomes elongating and terminating on reinitiation-permissive uORFs. The loss of the eIF4G contact with eIF4A specifically increased this retention and, as a result, increased the efficiency of reinitiation on downstream initiation codons. Combining the eIF4A-binding mutation with that affecting the integrity of the eIF4G1-RNA2-binding domain eliminated this specificity and produced epistatic interaction with a mutation in one specific cis-acting feature. We conclude that similar to humans, eIF4G is retained on ribosomes elongating uORFs to control reinitiation also in yeast.
- MeSH
- DEAD-box RNA-helikasy genetika MeSH
- eukaryotický iniciační faktor 3 genetika MeSH
- eukaryotický iniciační faktor 4E genetika MeSH
- eukaryotický iniciační faktor 4G genetika MeSH
- iniciace translace peptidového řetězce genetika MeSH
- kodon iniciační genetika MeSH
- lidé MeSH
- otevřené čtecí rámce genetika MeSH
- proteosyntéza genetika MeSH
- ribozomy genetika MeSH
- Saccharomyces cerevisiae - proteiny genetika MeSH
- Saccharomyces cerevisiae genetika MeSH
- transkripční faktory bZIP genetika MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Preeclampsia (PE) is a major cause of the pregnancy morbidity and mortality over the world. Disorganized placentation caused by trophoblast cell abnormity is one of main risk factors to induce PE. MiR-133a-3p has been shown to contain regulatory effects on oxidative stress in the cardiomyocytes. But the effects of miR-133a-3p on oxidative stress-induced apoptosis in the trophoblast cells remain unknown. In this study, trophoblast HTR-8/SVneo cells were transfected with miR-133a-3p mimics and inhibitor. H2O2 (250 microM) treatment of cells was adopted to induce oxidative stress. A series of typical molecular and cellular experiments was subsequently performed in order to investigate this issue. It was found that miR-133a-3p overexpression attenuated the oxidative stress induced by H2O2 through reduced ROS and MDA levels and enhanced antioxidase activities in the trophoblast cells. Overexpressed miR-133a-3p was shown to relieve the oxidative stress-induced apoptosis of HTR-8/SVneo cells. At molecular levels, a direct binding effect of miR-133a-3p on BACH1 was verified. Moreover, miR-133a-3p overexpression also enhanced BACH1 downstream Nrf2/HO-1 signaling to activate antioxidant genes. It is collectively demonstrated that miR-133a-3p can relieve the oxidative stress-induced apoptosis in the trophoblast cells through the BACH1/Nrf2/HO-1 signaling pathway via targeting BACH1 directly. This regulatory mechanism of miR-133a-3p in the trophoblast cells under oxidative stress may give a new perspective for oxidative stress-induced trophoblast cell abnormality and be useful to study more pathological mechanisms of PE.
- MeSH
- apoptóza účinky léků MeSH
- buněčné linie MeSH
- faktor 2 související s NF-E2 metabolismus MeSH
- hemoxygenasa-1 metabolismus MeSH
- lidé MeSH
- mikro RNA aplikace a dávkování genetika MeSH
- oxidační stres účinky léků MeSH
- preeklampsie metabolismus patologie prevence a kontrola MeSH
- signální transdukce MeSH
- těhotenství MeSH
- transkripční faktory bZIP metabolismus MeSH
- trofoblasty účinky léků metabolismus patologie MeSH
- Check Tag
- lidé MeSH
- těhotenství MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
Heat stress (HS) is a major abiotic stress that negatively impacts crop yields across the globe. Plants respond to elevated temperatures by changing gene expression, mediated by transcription factors (TFs) functioning to enhance HS tolerance. The involvement of Group I bZIP TFs in the heat stress response (HSR) is not known. In this study, bZIP18 and bZIP52 were investigated for their possible role in the HSR. Localization experiments revealed their nuclear accumulation following heat stress, which was found to be triggered by dephosphorylation. Both TFs were found to possess two motifs containing serine residues that are candidates for phosphorylation. These motifs are recognized by 14-3-3 proteins, and bZIP18 and bZIP52 were found to bind 14-3-3 ε, the interaction of which sequesters them to the cytoplasm. Mutation of both residues abolished 14-3-3 ε interaction and led to a strict nuclear localization for both TFs. RNA-seq analysis revealed coordinated downregulation of several metabolic pathways including energy metabolism and translation, and upregulation of numerous lncRNAs in particular. These results support the idea that bZIP18 and bZIP52 are sequestered to the cytoplasm under control conditions, and that heat stress leads to their re-localization to nuclei, where they jointly regulate gene expression.
- MeSH
- Arabidopsis genetika růst a vývoj MeSH
- buněčné jádro genetika MeSH
- proteiny 14-3-3 genetika MeSH
- proteiny huseníčku genetika MeSH
- reakce na tepelný šok genetika MeSH
- regulace genové exprese u rostlin genetika MeSH
- RNA dlouhá nekódující genetika MeSH
- transkripční faktory genetika MeSH
- Publikační typ
- časopisecké články MeSH
Translational control targeting the initiation phase is central to the regulation of gene expression. Understanding all of its aspects requires substantial technological advancements. Here we modified yeast translation complex profile sequencing (TCP-seq), related to ribosome profiling, and adapted it for mammalian cells. Human TCP-seq, capable of capturing footprints of 40S subunits (40Ss) in addition to 80S ribosomes (80Ss), revealed that mammalian and yeast 40Ss distribute similarly across 5'TRs, indicating considerable evolutionary conservation. We further developed yeast and human selective TCP-seq (Sel-TCP-seq), enabling selection of 40Ss and 80Ss associated with immuno-targeted factors. Sel-TCP-seq demonstrated that eIF2 and eIF3 travel along 5' UTRs with scanning 40Ss to successively dissociate upon AUG recognition; notably, a proportion of eIF3 lingers on during the initial elongation cycles. Highlighting Sel-TCP-seq versatility, we also identified four initiating 48S conformational intermediates, provided novel insights into ATF4 and GCN4 mRNA translational control, and demonstrated co-translational assembly of initiation factor complexes.
- MeSH
- 5' nepřekládaná oblast MeSH
- eukaryotický iniciační faktor 2 genetika metabolismus MeSH
- eukaryotický iniciační faktor 3 genetika metabolismus MeSH
- HEK293 buňky MeSH
- iniciační faktory genetika metabolismus MeSH
- kodon iniciační MeSH
- lidé MeSH
- malé podjednotky ribozomu eukaryotické genetika metabolismus MeSH
- multiproteinové komplexy genetika metabolismus MeSH
- proteosyntéza * MeSH
- ribozomy genetika metabolismus MeSH
- Saccharomyces cerevisiae - proteiny genetika metabolismus MeSH
- Saccharomyces cerevisiae genetika MeSH
- transkripční faktor ATF4 genetika metabolismus MeSH
- transkripční faktory bZIP genetika metabolismus MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
The Hodgkin/Reed-Sternberg cells of classical Hodgkin lymphoma (HL) are characterised by the aberrant activation of multiple signalling pathways. Here we show that a subset of HL displays altered expression of sphingosine-1-phosphate (S1P) receptors (S1PR)s. S1P activates phosphatidylinositide 3-kinase (PI3-K) in these cells that is mediated by the increased expression of S1PR1 and the decreased expression of S1PR2. We also showed that genes regulated by the PI3-K signalling pathway in HL cell lines significantly overlap with the transcriptional programme of primary HRS cells. Genes upregulated by the PI3-K pathway included the basic leucine zipper transcription factor, ATF-like 3 (BATF3), which is normally associated with the development of dendritic cells. Immunohistochemistry confirmed that BATF3 was expressed in HRS cells of most HL cases. In contrast, in normal lymphoid tissues, BATF3 expression was confined to a small fraction of CD30-positive immunoblasts. Knockdown of BATF3 in HL cell lines revealed that BATF3 contributed to the transcriptional programme of primary HRS cells, including the upregulation of S1PR1. Our data suggest that disruption of this potentially oncogenic feedforward S1P signalling loop could provide novel therapeutic opportunities for patients with HL.
- MeSH
- buněčné linie MeSH
- fosfatidylinositol-3-kinasy genetika MeSH
- genetická transkripce genetika MeSH
- HEK293 buňky MeSH
- Hodgkinova nemoc genetika MeSH
- lidé MeSH
- nádorové buněčné linie MeSH
- nádorové buňky kultivované MeSH
- receptory lysosfingolipidů genetika MeSH
- regulace genové exprese u nádorů genetika MeSH
- signální transdukce genetika MeSH
- transkripční faktory bZIP genetika MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Research Support, N.I.H., Extramural MeSH
KEY MESSAGE : bZIP TF network in pollen. Transcriptional control of gene expression represents an important mechanism guiding organisms through developmental processes and providing plasticity towards environmental stimuli. Because of their sessile nature, plants require effective gene regulation for rapid response to variation in environmental and developmental conditions. Transcription factors (TFs) provide such control ensuring correct gene expression in spatial and temporal manner. Our work reports the interaction network of six bZIP TFs expressed in Arabidopsis thaliana pollen and highlights the potential functional role for AtbZIP18 in pollen. AtbZIP18 was shown to interact with three other pollen-expressed bZIP TFs-AtbZIP34, AtbZIP52, and AtbZIP61 in yeast two-hybrid assays. AtbZIP18 transcripts are highly expressed in pollen, and at the subcellular level, an AtbZIP18-GFP fusion protein was located in the nucleus and cytoplasm/ER. To address the role of AtbZIP18 in the male gametophyte, we performed phenotypic analysis of a T-DNA knockout allele, which showed slightly reduced transmission through the male gametophyte. Some of the phenotype defects in atbzip18 pollen, although observed at low penetrance, were similar to those seen at higher frequency in the T-DNA knockout of the interacting partner, AtbZIP34. To gain deeper insight into the regulatory role of AtbZIP18, we analysed atbzip18/- pollen microarray data. Our results point towards a potential repressive role for AtbZIP18 and its functional redundancy with AtbZIP34 in pollen.
- MeSH
- Arabidopsis cytologie metabolismus ultrastruktura MeSH
- dimerizace MeSH
- DNA rostlinná MeSH
- inzerční mutageneze MeSH
- proteiny huseníčku metabolismus MeSH
- pyl genetika růst a vývoj metabolismus ultrastruktura MeSH
- regulace genové exprese u rostlin MeSH
- rekombinantní fúzní proteiny metabolismus MeSH
- trans-aktivátory metabolismus MeSH
- transkripční faktory bZIP metabolismus MeSH
- vazba proteinů MeSH
- Publikační typ
- časopisecké články MeSH