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1.
Mol Cell ; 81(10): 2094-2111.e9, 2021 05 20.
Article in English | MEDLINE | ID: mdl-33878293

ABSTRACT

Even though SYK and ZAP70 kinases share high sequence homology and serve analogous functions, their expression in B and T cells is strictly segregated throughout evolution. Here, we identified aberrant ZAP70 expression as a common feature in a broad range of B cell malignancies. We validated SYK as the kinase that sets the thresholds for negative selection of autoreactive and premalignant clones. When aberrantly expressed in B cells, ZAP70 competes with SYK at the BCR signalosome and redirects SYK from negative selection to tonic PI3K signaling, thereby promoting B cell survival. In genetic mouse models for B-ALL and B-CLL, conditional expression of Zap70 accelerated disease onset, while genetic deletion impaired malignant transformation. Inducible activation of Zap70 during B cell development compromised negative selection of autoreactive B cells, resulting in pervasive autoantibody production. Strict segregation of the two kinases is critical for normal B cell selection and represents a central safeguard against the development of autoimmune disease and B cell malignancies.


Subject(s)
Autoimmunity , Neoplasms/enzymology , Neoplasms/prevention & control , Syk Kinase/metabolism , ZAP-70 Protein-Tyrosine Kinase/metabolism , Animals , Antigens, CD19/metabolism , B-Lymphocytes , Calcium/metabolism , Cell Differentiation , Cell Transformation, Neoplastic , Enzyme Activation , Humans , Immune Tolerance , Lymphoma, B-Cell/enzymology , Lymphoma, B-Cell/pathology , Mice , Models, Genetic , NFATC Transcription Factors/metabolism , Neoplasm Proteins , Phosphatidylinositol 3-Kinases/metabolism , Protein Binding , Receptors, Antigen, B-Cell/metabolism , Signal Transduction
2.
Cell ; 152(4): 714-26, 2013 Feb 14.
Article in English | MEDLINE | ID: mdl-23415222

ABSTRACT

Clonal evolution is a key feature of cancer progression and relapse. We studied intratumoral heterogeneity in 149 chronic lymphocytic leukemia (CLL) cases by integrating whole-exome sequence and copy number to measure the fraction of cancer cells harboring each somatic mutation. We identified driver mutations as predominantly clonal (e.g., MYD88, trisomy 12, and del(13q)) or subclonal (e.g., SF3B1 and TP53), corresponding to earlier and later events in CLL evolution. We sampled leukemia cells from 18 patients at two time points. Ten of twelve CLL cases treated with chemotherapy (but only one of six without treatment) underwent clonal evolution, predominantly involving subclones with driver mutations (e.g., SF3B1 and TP53) that expanded over time. Furthermore, presence of a subclonal driver mutation was an independent risk factor for rapid disease progression. Our study thus uncovers patterns of clonal evolution in CLL, providing insights into its stepwise transformation, and links the presence of subclones with adverse clinical outcomes.


Subject(s)
Leukemia, Lymphocytic, Chronic, B-Cell/genetics , Mutation , Algorithms , Animals , B-Lymphocytes/metabolism , DNA Copy Number Variations , Genome-Wide Association Study , Humans , Leukemia, Lymphocytic, Chronic, B-Cell/drug therapy , Ploidies
3.
EMBO J ; 42(7): e112756, 2023 04 03.
Article in English | MEDLINE | ID: mdl-36815434

ABSTRACT

DNA double-strand breaks (DSBs) are one of the most toxic forms of DNA damage, which threatens genome stability. Homologous recombination is an error-free DSB repair pathway, in which the evolutionarily conserved SMC5/6 complex (SMC5/6) plays essential roles. The PAF1 complex (PAF1C) is well known to regulate transcription. Here we show that SMC5/6 recruits PAF1C to facilitate DSB repair in plants. In a genetic screen for DNA damage response mutants (DDRMs), we found that the Arabidopsis ddrm4 mutant is hypersensitive to DSB-inducing agents and is defective in homologous recombination. DDRM4 encodes PAF1, a core subunit of PAF1C. Further biochemical and genetic studies reveal that SMC5/6 recruits PAF1C to DSB sites, where PAF1C further recruits the E2 ubiquitin-conjugating enzymes UBC1/2, which interact with the E3 ubiquitin ligases HUB1/2 to mediate the monoubiquitination of histone H2B at DSBs. These results implicate SMC5/6-PAF1C-UBC1/2-HUB1/2 as a new axis for DSB repair through homologous recombination, revealing a new mechanism of SMC5/6 and uncovering a novel function of PAF1C.


Subject(s)
Arabidopsis , DNA Breaks, Double-Stranded , Arabidopsis/genetics , Arabidopsis/metabolism , DNA Repair , DNA/metabolism , Histones/metabolism
4.
Plant Cell ; 35(2): 910-923, 2023 02 20.
Article in English | MEDLINE | ID: mdl-36503931

ABSTRACT

DNA replication stress threatens genome stability and affects plant growth and development. How plants resolve replication stress is poorly understood. The protein kinase WEE1-mediated cell cycle arrest is required for replication stress responses. The E3 ubiquitin ligases anaphase-promoting complex/cyclosome (APC/C) and Skp1/Cullin 1/F-box (SCF) are essential regulators of the cell cycle. Here, we show that APC/CCDC20 mediates the degradation of SCFFBL17 during replication stress responses in Arabidopsis thaliana. Biochemically, WEE1 interacts with and phosphorylates the APC/C co-activator APC10, which enhances the interaction between F-BOX-LIKE17 (FBL17) and CELL DIVISION CYCLE 20 (CDC20), an activator of APC/C. Both APC10 and CDC20 are required for the polyubiquitination and degradation of FBL17. Genetically, silencing CDC20 or APC10 confers plant hypersensitivity to replication stress, which is suppressed by loss of FBL17. Collectively, our study suggests that WEE1 activates APC/C to inhibit FBL17, providing insight into replication stress responses in plants.


Subject(s)
Arabidopsis , Arabidopsis/metabolism , Cell Cycle Proteins/genetics , Cell Cycle Proteins/metabolism , Cell Cycle/physiology , Anaphase-Promoting Complex-Cyclosome/genetics , Anaphase-Promoting Complex-Cyclosome/metabolism , Ubiquitin-Protein Ligases/metabolism , Cdc20 Proteins/metabolism
5.
Plant Cell ; 35(8): 3021-3034, 2023 08 02.
Article in English | MEDLINE | ID: mdl-37159556

ABSTRACT

DNA replication stress threatens genome stability and is a hallmark of cancer in humans. The evolutionarily conserved kinases ATR (ATM and RAD3-related) and WEE1 are essential for the activation of replication stress responses. Translational control is an important mechanism that regulates gene expression, but its role in replication stress responses is largely unknown. Here we show that ATR-WEE1 control the translation of SUPPRESSOR OF GAMMA RESPONSE 1 (SOG1), a master transcription factor required for replication stress responses in Arabidopsis thaliana. Through genetic screening, we found that the loss of GENERAL CONTROL NONDEREPRESSIBLE 20 (GCN20) or GCN1, which function together to inhibit protein translation, suppressed the hypersensitivity of the atr or wee1 mutant to replication stress. Biochemically, WEE1 inhibits GCN20 by phosphorylating it; phosphorylated GCN20 is subsequently polyubiquitinated and degraded. Ribosome profiling experiments revealed that that loss of GCN20 enhanced the translation efficiency of SOG1, while overexpressing GCN20 had the opposite effect. The loss of SOG1 reduced the resistance of wee1 gcn20 to replication stress, whereas overexpressing SOG1 enhanced the resistance to atr or wee1 to replication stress. These results suggest that ATR-WEE1 inhibits GCN20-GCN1 activity to promote the translation of SOG1 during replication stress. These findings link translational control to replication stress responses in Arabidopsis.


Subject(s)
Arabidopsis Proteins , Arabidopsis , Humans , Transcription Factors/metabolism , Protein Serine-Threonine Kinases/metabolism , Protein Kinases/metabolism , Arabidopsis/genetics , Arabidopsis/metabolism , Ataxia Telangiectasia Mutated Proteins/genetics , DNA Damage , DNA Replication/genetics , Cell Cycle Proteins/genetics , Cell Cycle Proteins/metabolism , Protein-Tyrosine Kinases/genetics , Protein-Tyrosine Kinases/metabolism , Arabidopsis Proteins/genetics , Arabidopsis Proteins/metabolism
6.
Proc Natl Acad Sci U S A ; 120(21): e2220173120, 2023 05 23.
Article in English | MEDLINE | ID: mdl-37186820

ABSTRACT

Human serum albumin (HSA) is a highly water-soluble protein with 67% alpha-helix content and three distinct domains (I, II, and III). HSA offers a great promise in drug delivery with enhanced permeability and retention effect. But it is hindered by protein denaturation during drug entrapment or conjugation that result in distinct cellular transport pathways and reduction of biological activities. Here we report using a protein design approach named reverse-QTY (rQTY) code to convert specific hydrophilic alpha-helices to hydrophobic to alpha-helices. The designed HSA undergo self-assembly of well-ordered nanoparticles with highly biological actives. The hydrophilic amino acids, asparagine (N), glutamine (Q), threonine (T), and tyrosine (Y) in the helical B-subdomains of HSA were systematically replaced by hydrophobic leucine (L), valine (V), and phenylalanine (F). HSArQTY nanoparticles exhibited efficient cellular internalization through the cell membrane albumin binding protein GP60, or SPARC (secreted protein, acidic and rich in cysteine)-mediated pathways. The designed HSArQTY variants displayed superior biological activities including: i) encapsulation of drug doxorubicin, ii) receptor-mediated cellular transport, iii) tumor cell targeting, and iv) antitumor efficiency compare to denatured HSA nanoparticles. HSArQTY nanoparticles provided superior tumor targeting and antitumor therapeutic effects compared to the albumin nanoparticles fabricated by antisolvent precipitation method. We believe that the rQTY code is a robust platform for specific hydrophobic modification of functional hydrophilic proteins with clear-defined binding interfaces.


Subject(s)
Antineoplastic Agents , Nanoparticles , Humans , Animals , Mice , Serum Albumin, Human/chemistry , Antineoplastic Agents/pharmacology , Antineoplastic Agents/chemistry , Doxorubicin/pharmacology , Doxorubicin/chemistry , Drug Delivery Systems , Albumins , Nanoparticles/chemistry , Cell Line, Tumor , Drug Carriers/chemistry
7.
Proc Natl Acad Sci U S A ; 120(4): e2217145120, 2023 01 24.
Article in English | MEDLINE | ID: mdl-36649415

ABSTRACT

Entomopathogenic fungi infect insects by penetrating through the cuticle into the host body. To breach the host cuticle, some fungal pathogens produce specialized infection cells called appressoria, which develop enormous turgor pressure to allow cuticle penetration. However, regulatory mechanisms underlying appressorium turgor generation are poorly understood. Here, we show that the histone lysine methyltransferase ASH1 in the insecticidal fungus Metarhizium robertsii, which is strongly induced during infection of the mosquito cuticle, regulates appressorium turgor generation and cuticle penetration by activating the peroxin gene Mrpex16 via H3K36 dimethylation. MrPEX16 is required for the biogenesis of peroxisomes that participate in lipid catabolism and further promotes the hydrolysis of triacylglycerols stored in lipid droplets to produce glycerol for turgor generation, facilitating appressorium-mediated insect infection. Together, the ASH1-PEX16 pathway plays a pivotal role in regulating peroxisome biogenesis to promote lipolysis for appressorium turgor generation, providing insights into the molecular mechanisms underlying fungal pathogenesis.


Subject(s)
Fungal Proteins , Peroxisomes , Animals , Peroxisomes/metabolism , Fungal Proteins/genetics , Fungal Proteins/metabolism , Insecta/metabolism , Plant Diseases/microbiology
8.
J Virol ; 98(7): e0046724, 2024 Jul 23.
Article in English | MEDLINE | ID: mdl-38864621

ABSTRACT

Acinetobacter baumannii, an opportunistic pathogen, poses a significant threat in intensive care units, leading to severe nosocomial infections. The rise of multi-drug-resistant strains, particularly carbapenem-resistant A. baumannii, has created formidable challenges for effective treatment. Given the prolonged development cycle and high costs associated with antibiotics, phages have garnered clinical attention as an alternative for combating infections caused by drug-resistant bacteria. However, the utilization of phage therapy encounters notable challenges, including the narrow host spectrum, where each phage targets a limited subset of bacteria, increasing the risk of phage resistance development. Additionally, uncertainties in immune system dynamics during treatment hinder tailoring symptomatic interventions based on patient-specific states. In this study, we isolated two A. baumannii phages from wastewater and conducted a comprehensive assessment of their potential applications. This evaluation included sequencing analysis, genome classification, pH and temperature stability assessments, and in vitro bacterial inhibition assays. Further investigations involved analyzing histological and cytokine alterations in rats undergoing phage cocktail treatment for pneumonia. The therapeutic efficacy of the phages was validated, and transcriptomic studies of rat lung tissue during phage treatment revealed crucial changes in the immune system. The findings from our study underscore the potential of phages for future development as a treatment strategy and offer compelling evidence regarding immune system dynamics throughout the treatment process.IMPORTANCEDue to the growing problem of multi-drug-resistant bacteria, the use of phages is being considered as an alternative to antibiotics, and the genetic safety and application stability of phages determine the potential of phage application. The absence of drug resistance genes and virulence genes in the phage genome can ensure the safety of phage application, and the fact that phage can remain active in a wide range of temperatures and pH is also necessary for application. In addition, the effect evaluation of preclinical studies is especially important for clinical application. By simulating the immune response situation during the treatment process through mammalian models, the changes in animal immunity can be observed, and the effect of phage therapy can be further evaluated. Our study provides compelling evidence that phages hold promise for further development as therapeutic agents for Acinetobacter baumannii infections.


Subject(s)
Acinetobacter Infections , Acinetobacter baumannii , Bacteriophages , Carbapenems , Disease Models, Animal , Phage Therapy , Acinetobacter baumannii/virology , Acinetobacter baumannii/drug effects , Animals , Acinetobacter Infections/therapy , Acinetobacter Infections/microbiology , Rats , Phage Therapy/methods , Carbapenems/pharmacology , Bacteriophages/physiology , Bacteriophages/genetics , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/therapeutic use , Drug Resistance, Multiple, Bacterial , Male , Genome, Viral , Wastewater , Pneumonia/therapy , Pneumonia/microbiology , Pneumonia/virology
9.
Plant Physiol ; 194(4): 2149-2164, 2024 Mar 29.
Article in English | MEDLINE | ID: mdl-37992039

ABSTRACT

Transgenes are often spontaneously silenced, which hinders the application of genetic modifications to crop breeding. While gene silencing has been extensively studied in Arabidopsis (Arabidopsis thaliana), the molecular mechanism of transgene silencing remains elusive in crop plants. We used rice (Oryza sativa) plants silenced for a 35S::OsGA2ox1 (Gibberellin 2-oxidase 1) transgene to isolate five elements mountain (fem) mutants showing restoration of transgene expression. In this study, we isolated multiple fem2 mutants defective in a homolog of Required to Maintain Repression 1 (RMR1) of maize (Zea mays) and CLASSY (CLSY) of Arabidopsis. In addition to failing to maintain transgene silencing, as occurs in fem3, in which mutation occurs in NUCLEAR RNA POLYMERASE E1 (OsNRPE1), the fem2 mutant failed to establish transgene silencing of 35S::OsGA2ox1. Mutation in FEM2 eliminated all RNA POLYMERASE IV (Pol-IV)-FEM1/OsRDR2 (RNA-DEPENDENT RNA POLYMERASE 2)-dependent small interfering RNAs (siRNAs), reduced DNA methylation on genome-wide scale in rice seedlings, caused pleiotropic developmental defects, and increased disease resistance. Simultaneous mutation in 2 FEM2 homologous genes, FEM2-Like 1 (FEL1) and FEL2, however, did not affect DNA methylation and rice development and disease resistance. The predominant expression of FEM2 over FEL1 and FEL2 in various tissues was likely caused by epigenetic states. Overexpression of FEL1 but not FEL2 partially rescued hypomethylation of fem2, indicating that FEL1 maintains the cryptic function. In summary, FEM2 is essential for establishing and maintaining gene silencing; moreover, FEM2 is solely required for Pol IV-FEM1 siRNA biosynthesis and de novo DNA methylation.


Subject(s)
Arabidopsis Proteins , Arabidopsis , Oryza , Oryza/genetics , Oryza/metabolism , Arabidopsis/genetics , Chromatin/metabolism , RNA, Small Interfering/genetics , RNA, Small Interfering/metabolism , Disease Resistance/genetics , Plant Breeding , DNA Methylation/genetics , DNA-Directed RNA Polymerases/genetics , DNA-Directed RNA Polymerases/metabolism , Arabidopsis Proteins/metabolism , Plants/metabolism , Genomics , Mutation/genetics
10.
Rev Med Virol ; 34(4): e2565, 2024 Jul.
Article in English | MEDLINE | ID: mdl-39031738

ABSTRACT

Global attention is riveted on neurodegenerative diseases due to their unresolved aetiologies and lack of efficacious therapies. Two key factors implicated include mitochondrial impairment and microglial ageing. Several viral infections, including Herpes simplex virus-1 (HSV-1), human immunodeficiency virus (HIV) and Epstein-Barr virus, are linked to heightened risk of these disorders. Surprisingly, numerous studies indicate viruses induce these aforementioned precipitating events. Epstein-Barr virus, Hepatitis C Virus, HIV, respiratory syncytial virus, HSV-1, Japanese Encephalitis Virus, Zika virus and Enterovirus 71 specifically impact mitochondrial function, leading to mitochondrial malfunction. These vital organelles govern various cell activities and, under specific circumstances, trigger microglial ageing. This article explores the role of viral infections in elucidating the pathogenesis of neurodegenerative ailments. Various viruses instigate microglial ageing via mitochondrial destruction, causing senescent microglia to exhibit activated behaviour, thereby inducing neuroinflammation and contributing to neurodegeneration.


Subject(s)
Microglia , Mitochondria , Neurodegenerative Diseases , Virus Diseases , Humans , Neurodegenerative Diseases/virology , Neurodegenerative Diseases/pathology , Mitochondria/metabolism , Virus Diseases/virology , Virus Diseases/pathology , Microglia/virology , Microglia/pathology , Animals
11.
Exp Cell Res ; 439(1): 114076, 2024 Jun 01.
Article in English | MEDLINE | ID: mdl-38719174

ABSTRACT

Glioblastoma (GBM) is a common primary central nervous system tumor. The molecular mechanisms of glioma are unknown, and the prognosis is poor. Therefore, exploring the underlying mechanisms and screening for new prognostic markers and therapeutic targets is crucial. We utilized the weighted gene co-expression network analysis (WGCNA), Differentially Expressed Genes (DEGs), and LASSO-COX analysis to identify three target genes. Next, we constructed and evaluated a prognostic model, screening out COL8A1 as a risk gene. Through a sequence of cellular functional experiments, in vivo studies, and RNA sequencing, we delved into exploring the functional effects and molecular mechanisms of COL8A1 on GBM cells. Finally, the correlation between COL8A1 and tumor immune cells and different inflammatory responses was analyzed. Immunohistochemistry experiments revealed the influence of COL8A1 on macrophage polarization. The COL8A1 expression level was associated with the grade, prognosis, and tumor microenvironment (TME) of glioma. Functional experiments showed that COL8A1 inhibited GBM cell apoptosis and promoted migration, invasion, and proliferation in vitro and in vivo. We also found that COL8A1 promotes the epithelial-mesenchymal transition process and may mediate the activation of the ERK pathway through SHC1. In addition, immune infiltration analysis showed that COL8A1 was closely associated with macrophages in glioma tissues, significantly suppressing the signaling of M1-like -type macrophages and enhancing the signaling of M2-like -type macrophages. COL8A1 was first found to be associated with prognosis, progression, and immune microenvironment of glioma and may serve as a new marker of prognosis and a therapeutic target.


Subject(s)
Biomarkers, Tumor , Brain Neoplasms , Cell Movement , Cell Proliferation , Gene Expression Regulation, Neoplastic , Glioma , Tumor Microenvironment , Animals , Female , Humans , Male , Mice , Apoptosis/genetics , Biomarkers, Tumor/genetics , Biomarkers, Tumor/metabolism , Brain Neoplasms/pathology , Brain Neoplasms/genetics , Brain Neoplasms/metabolism , Cell Line, Tumor , Cell Movement/genetics , Cell Proliferation/genetics , Epithelial-Mesenchymal Transition/genetics , Glioblastoma/pathology , Glioblastoma/genetics , Glioblastoma/metabolism , Glioma/genetics , Glioma/pathology , Glioma/metabolism , Mice, Nude , Prognosis , Tumor Microenvironment/genetics
12.
Nature ; 569(7757): 576-580, 2019 05.
Article in English | MEDLINE | ID: mdl-31092926

ABSTRACT

Genetic and epigenetic intra-tumoral heterogeneity cooperate to shape the evolutionary course of cancer1. Chronic lymphocytic leukaemia (CLL) is a highly informative model for cancer evolution as it undergoes substantial genetic diversification and evolution after therapy2,3. The CLL epigenome is also an important disease-defining feature4,5, and growing populations of cells in CLL diversify by stochastic changes in DNA methylation known as epimutations6. However, previous studies using bulk sequencing methods to analyse the patterns of DNA methylation were unable to determine whether epimutations affect CLL populations homogeneously. Here, to measure the epimutation rate at single-cell resolution, we applied multiplexed single-cell reduced-representation bisulfite sequencing to B cells from healthy donors and patients with CLL. We observed that the common clonal origin of CLL results in a consistently increased epimutation rate, with low variability in the cell-to-cell epimutation rate. By contrast, variable epimutation rates across healthy B cells reflect diverse evolutionary ages across the trajectory of B cell differentiation, consistent with epimutations serving as a molecular clock. Heritable epimutation information allowed us to reconstruct lineages at high-resolution with single-cell data, and to apply this directly to patient samples. The CLL lineage tree shape revealed earlier branching and longer branch lengths than in normal B cells, reflecting rapid drift after the initial malignant transformation and a greater proliferative history. Integration of single-cell bisulfite sequencing analysis with single-cell transcriptomes and genotyping confirmed that genetic subclones mapped to distinct clades, as inferred solely on the basis of epimutation information. Finally, to examine potential lineage biases during therapy, we profiled serial samples during ibrutinib-associated lymphocytosis, and identified clades of cells that were preferentially expelled from the lymph node after treatment, marked by distinct transcriptional profiles. The single-cell integration of genetic, epigenetic and transcriptional information thus charts the lineage history of CLL and its evolution with therapy.


Subject(s)
Cell Lineage , Epigenesis, Genetic , Evolution, Molecular , Leukemia, Lymphocytic, Chronic, B-Cell/genetics , Leukemia, Lymphocytic, Chronic, B-Cell/pathology , Base Sequence , Biological Clocks , Cell Lineage/genetics , DNA Methylation , Epigenome/genetics , Gene Expression Regulation, Neoplastic , Humans , Leukemia, Lymphocytic, Chronic, B-Cell/metabolism , Mutation Rate , Sequence Analysis, RNA , Single-Cell Analysis , Transcription, Genetic
13.
Nucleic Acids Res ; 51(14): 7288-7313, 2023 08 11.
Article in English | MEDLINE | ID: mdl-37378433

ABSTRACT

We have conducted a detailed transcriptomic, proteomic and phosphoproteomic analysis of CDK8 and its paralog CDK19, alternative enzymatic components of the kinase module associated with transcriptional Mediator complex and implicated in development and diseases. This analysis was performed using genetic modifications of CDK8 and CDK19, selective CDK8/19 small molecule kinase inhibitors and a potent CDK8/19 PROTAC degrader. CDK8/19 inhibition in cells exposed to serum or to agonists of NFκB or protein kinase C (PKC) reduced the induction of signal-responsive genes, indicating a pleiotropic role of Mediator kinases in signal-induced transcriptional reprogramming. CDK8/19 inhibition under basal conditions initially downregulated a small group of genes, most of which were inducible by serum or PKC stimulation. Prolonged CDK8/19 inhibition or mutagenesis upregulated a larger gene set, along with a post-transcriptional increase in the proteins comprising the core Mediator complex and its kinase module. Regulation of both RNA and protein expression required CDK8/19 kinase activities but both enzymes protected their binding partner cyclin C from proteolytic degradation in a kinase-independent manner. Analysis of isogenic cell populations expressing CDK8, CDK19 or their kinase-inactive mutants revealed that CDK8 and CDK19 have the same qualitative effects on protein phosphorylation and gene expression at the RNA and protein levels, whereas differential effects of CDK8 versus CDK19 knockouts were attributable to quantitative differences in their expression and activity rather than different functions.


Subject(s)
Cyclin-Dependent Kinases , Mediator Complex , Humans , Cyclin-Dependent Kinases/genetics , Cyclin-Dependent Kinases/metabolism , Mediator Complex/genetics , Mediator Complex/metabolism , Phosphorylation , Proteomics , RNA/metabolism
14.
Proc Natl Acad Sci U S A ; 119(16): e2202970119, 2022 04 19.
Article in English | MEDLINE | ID: mdl-35412914

ABSTRACT

Homologous recombination repair (HR) is an error-free DNA damage repair pathway to maintain genome stability and a basis of gene targeting using genome-editing tools. However, the mechanisms of HR in plants are still poorly understood. Through genetic screens for DNA damage response mutants (DDRM) in Arabidopsis, we find that a plant-specific ubiquitin E3 ligase DDRM1 is required for HR. DDRM1 contains an N-terminal BRCT (BRCA1 C-terminal) domain and a C-terminal RING (really interesting new gene) domain and is highly conserved in plants including mosses. The ddrm1 mutant is defective in HR and thus is hypersensitive to DNA-damaging reagents. Biochemical studies reveal that DDRM1 interacts with and ubiquitinates the transcription factor SOG1, a plant-specific master regulator of DNA damage responses. Interestingly, DDRM1-mediated ubiquitination promotes the stability of SOG1. Consistently, genetic data support that SOG1 functions downstream of DDRM1. Our study reveals that DDRM1-SOG1 is a plant-specific module for HR and highlights the importance of ubiquitination in HR.


Subject(s)
Arabidopsis Proteins , Arabidopsis , Recombinational DNA Repair , Transcription Factors , Ubiquitin-Protein Ligases , Arabidopsis/genetics , Arabidopsis Proteins/genetics , Arabidopsis Proteins/metabolism , DNA Damage , Recombinational DNA Repair/genetics , Transcription Factors/genetics , Transcription Factors/metabolism , Ubiquitin-Protein Ligases/genetics , Ubiquitin-Protein Ligases/metabolism
15.
Nano Lett ; 24(27): 8445-8452, 2024 Jul 10.
Article in English | MEDLINE | ID: mdl-38917425

ABSTRACT

The interfacial FeSe/TiO2-δ coupling induces high-temperature superconductivity in monolayer FeSe films. Using cryogenic atomically resolved scanning tunneling microscopy/spectroscopy, we obtained atomic-site dependent surface density of states, work function, and the pairing gap in the monolayer FeSe on the SrTiO3(001)-(√13 × âˆš13)-R33.7° surface. Our results disclosed the out-of-plane Se-Fe-Se triple layer gradient variation, switched DOS for Fe sites on and off TiO5□, and inequivalent Fe sublattices, which gives global spatial modulation of pairing gap contaminants with the (√13 × âˆš13) pattern. Moreover, the coherent lattice coupling induces strong inversion asymmetry and in-plane anisotropy in the monolayer FeSe, which is demonstrated to correlate with the particle-hole asymmetry in coherence peaks. These results disclose delicate atomic-scale correlations between pairing and lattice-electronic coupling in the Bardeen-Cooper-Schrieffer to Bose-Einstein condensation crossover regime, providing insights into understanding the pairing mechanism of multiorbital superconductivity.

16.
Gene Ther ; 31(3-4): 128-143, 2024 Mar.
Article in English | MEDLINE | ID: mdl-37833563

ABSTRACT

Adeno-associated virus (AAV) vector gene therapy is a promising approach to treat rare genetic diseases; however, an ongoing challenge is how to best modulate host immunity to improve transduction efficiency and therapeutic outcomes. This report presents two studies characterizing multiple prophylactic immunosuppression regimens in male cynomolgus macaques receiving an AAVrh10 gene therapy vector expressing human coagulation factor VIII (hFVIII). In study 1, no immunosuppression was compared with prednisolone, rapamycin (or sirolimus), rapamycin and cyclosporin A in combination, and cyclosporin A and azathioprine in combination. Prednisolone alone demonstrated higher mean peripheral blood hFVIII expression; however, this was not sustained upon taper. Anti-capsid and anti-hFVIII antibody responses were robust, and vector genomes and transgene mRNA levels were similar to no immunosuppression at necropsy. Study 2 compared no immunosuppression with prednisolone alone or in combination with rapamycin or methotrexate. The prednisolone/rapamycin group demonstrated an increase in mean hFVIII expression and a mean delay in anti-capsid IgG development until after rapamycin taper. Additionally, a significant reduction in the plasma cell gene signature was observed with prednisolone/rapamycin, suggesting that rapamycin's tolerogenic effects may include plasma cell differentiation blockade. Immunosuppression with prednisolone and rapamycin in combination could improve therapeutic outcomes in AAV vector gene therapy.


Subject(s)
Cyclosporine , Sirolimus , Male , Humans , Animals , Sirolimus/pharmacology , Sirolimus/therapeutic use , Sirolimus/metabolism , Cyclosporine/metabolism , Plasma Cells , Prednisolone/pharmacology , Prednisolone/therapeutic use , Prednisolone/metabolism , Genetic Therapy , Genetic Vectors/genetics , Macaca/genetics , Dependovirus
17.
Mol Biol Evol ; 40(1)2023 01 04.
Article in English | MEDLINE | ID: mdl-36625089

ABSTRACT

Determining the functional consequences of karyotypic changes is invariably challenging because evolution tends to obscure many of its own footprints, such as accumulated mutations, recombination events, and demographic perturbations. Here, we describe the assembly of a chromosome-level reference genome of the gayal (Bos frontalis) thereby revealing the structure, at base-pair-level resolution, of a telo/acrocentric-to-telo/acrocentric Robertsonian translocation (2;28) (T/A-to-T/A rob[2;28]). The absence of any reduction in the recombination rate or genetic introgression within the fusion region of gayal served to challenge the long-standing view of a role for fusion-induced meiotic dysfunction in speciation. The disproportionate increase noted in the distant interactions across pro-chr2 and pro-chr28, and the change in open-chromatin accessibility following rob(2;28), may, however, have led to the various gene expression irregularities observed in the gayal. Indeed, we found that many muscle-related genes, located synthetically on pro-chr2 and pro-chr28, exhibited significant changes in expression. This, combined with genome-scale structural variants and expression alterations in genes involved in myofibril composition, may have driven the rapid sarcomere adaptation of gayal to its rugged mountain habitat. Our findings not only suggest that large-scale chromosomal changes can lead to alterations in genome-level expression, thereby promoting both adaptation and speciation, but also illuminate novel avenues for studying the relationship between karyotype evolution and speciation.


Subject(s)
Chromatin , Genome , Animals , Cattle
18.
Prostate ; 84(2): 131-147, 2024 Feb.
Article in English | MEDLINE | ID: mdl-37828768

ABSTRACT

BACKGROUND: Cancer stem cells (CSCs) are a small subpopulation of tumor cells with the capability of self-renewal and drug resistance, leading to tumor progression and disease relapse. Our study aimed to investigate the antitumor effect of berbamine, extracted from berberis amurensis, on prostate CSCs. METHODS: Sphere formation was used to collect prostate CSCs. The viability, proliferation, invasion, migration, and apoptosis assays were used to evaluate the antitumor effect of berbamine on prostate CSCs. Prostate CSC markers were analyzed by flow cytometry and qRT-PCR. Small RNA sequencing analysis was conducted to analyse miRNAs. Exosomes were extracted using the ExoQuick-TC kit and verified by testing exosomal markers using western blot. RESULTS: Berbamine targets prostate CSCs. Additionally, berbamine enhanced the antitumor effect of cabazitaxel, a second-line chemotherapeutic drug for advanced prostate cancer, and re-sensitized Cabazitaxel-resistant PCa cells (CabaR-DU145) to cabazitaxel by inhibiting ABCG2, CXCR4, IGF2BP1, and p-STAT3. Berbamine enhanced the expression of let-7 miRNA family and miR-26b and influenced the downstream targets IGF2BP1 and p-STAT3, respectively. Silencing CXCR4 and ABCG2 downregulated the expression of IGF2BP1 and p-STAT3, respectively. Importantly, berbamine enhanced also levels of exosomal let-7 family and miR-26b, suggesting that berbamine possibly influences the expression of let-7 family and miR-26b through exosome delivery. Exosomes derived from berbamine-treated CabaR-DU145 cells re-sensitized the cells to cabazitaxel. CONCLUSION: Berbamine enhanced the toxic activity of cabazitaxel and reversed cabazitaxel resistance potentially through CXCR4/exosomal let-7/IGF2BP1 and ABCG2/exosomal miR-26b/p-STAT3 axes.


Subject(s)
Exosomes , MicroRNAs , Prostatic Neoplasms , Male , Humans , Cell Line, Tumor , Neoplasm Recurrence, Local/pathology , MicroRNAs/genetics , MicroRNAs/metabolism , Prostatic Neoplasms/drug therapy , Prostatic Neoplasms/genetics , Prostatic Neoplasms/metabolism , Apoptosis , Neoplastic Stem Cells/metabolism , Cell Proliferation , Exosomes/metabolism , STAT3 Transcription Factor/metabolism
19.
Clin Immunol ; 258: 109859, 2024 01.
Article in English | MEDLINE | ID: mdl-38065368

ABSTRACT

The pathogenic anti-citrullinated protein antibodies (ACPA) are thought to play a vital role in the initiation and immune maintenance of rheumatoid arthritis (RA). However, it is noteworthy that ACPA is not a salient characteristic of any conventional RA animal model. Porphyromonas gingivalis (Pg) is the first microorganism identified to induce citrullination and a target of autoantibodies in early rheumatoid arthritis (RA). Thus, we employed C3H mice with specific MHC types and combined Pg infection with collagen immunity to develop an animal model of ACPA-positive RA. The resulting model exhibited citrullination characteristics, as well as pathological and immune cell changes. 1) Mice showed a significant increase in ACPA levels, and various organs and tissues exhibited elevated levels of citrullinated protein. 2) The mice experienced heightened pain, inflammation, and bone destruction. 3) The spleen and lymph nodes of the mice showed a significant increase in the proportion of Tfh-GCB cell subpopulations responsible for regulating autoantibody production. In conclusion, the C3H mouse model of Pg infection with collagen immunity demonstrated significant alterations in ACPA levels, citrullinated protein expression, and immune cell subpopulations, which could be a crucial factor leading to increased pain, inflammation, and bone destruction.


Subject(s)
Arthritis, Rheumatoid , Porphyromonas gingivalis , Animals , Mice , Mice, Inbred C3H , Autoantibodies , Immunization , Inflammation , Collagen , Pain
20.
J Gene Med ; 26(4): e3684, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38618694

ABSTRACT

BACKGROUND: Colon cancer is one of the most common digestive tract malignancies. Although immunotherapy has brought new hope to colon cancer patients, there is still a large proportion of patients who do not benefit from immunotherapy. Studies have shown that neutrophils can interact with immune cells and immune factors to affect the prognosis of patients. METHODS: We first determined the infiltration level of neutrophils in tumors using the CIBERSORT algorithm and identified key genes in the final risk model by Spearman correlation analysis and subsequent Cox analysis. The risk score of each patient was obtained by multiplying the Cox regression coefficient and the gene expression level, and patients were divided into two groups based on the median of risk score. Differences in overall survival (OS) and progression-free survival (PFS) were assessed by Kaplan-Meier survival analysis, and model accuracy was validated in independent dataset. Differences in immune infiltration and immunotherapy were evaluated by immunoassay. Finally, immunohistochemistry and western blotting were performed to verify the expression of the three genes in the colon normal and tumor tissues. RESULTS: We established and validated a risk scoring model based on neutrophil-related genes in two independent datasets, The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) database, with SLC11A1 and SLC2A3 as risk factors and MMP3 as a protective factor. A new nomogram was constructed and validated by combining clinical characteristics and the risk score model to better predict patients OS and PFS. Immune analysis showed that patients in the high-risk group had immune cell infiltration level, immune checkpoint level and tumor mutational burden, and were more likely to benefit from immunotherapy. CONCLUSIONS: The low-risk group showed better OS and PFS than the high-risk group in the neutrophil-related gene-based risk model. Patients in the high-risk group presented higher immune infiltration levels and tumor mutational burden and thus may be more responsive to immunotherapy.


Subject(s)
Colonic Neoplasms , Neutrophils , Humans , Colonic Neoplasms/genetics , Colonic Neoplasms/therapy , Risk Factors , Algorithms , Immunotherapy
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