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1.
PLoS Pathog ; 16(9): e1008879, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32997728

RESUMO

The Human T-cell leukemia virus type 1 (HTLV-1) orf I-encoded accessory protein p8 is cleaved from its precursor p12, and both proteins contribute to viral persistence. p8 induces cellular protrusions, which are thought to facilitate transfer of p8 to target cells and virus transmission. Host factors interacting with p8 and mediating p8 transfer are unknown. Here, we report that vasodilator-stimulated phosphoprotein (VASP), which promotes actin filament elongation, is a novel interaction partner of p8 and important for p8 and HTLV-1 Gag cell-to-cell transfer. VASP contains an Ena/VASP homology 1 (EVH1) domain that targets the protein to focal adhesions. Bioinformatics identified a short stretch in p8 (amino acids (aa) 24-45) which may mediate interactions with the EVH1 domain of VASP. Co-immunoprecipitations confirmed interactions of VASP:p8 in 293T, Jurkat and HTLV-1-infected MT-2 cells. Co-precipitation of VASP:p8 could be significantly blocked by peptides mimicking aa 26-37 of p8. Mutational studies revealed that the EVH1-domain of VASP is necessary, but not sufficient for the interaction with p8. Further, deletion of the VASP G- and F-actin binding domains significantly diminished co-precipitation of p8. Imaging identified areas of partial co-localization of VASP with p8 at the plasma membrane and in protrusive structures, which was confirmed by proximity ligation assays. Co-culture experiments revealed that p8 is transferred between Jurkat T-cells via VASP-containing conduits. Imaging and flow cytometry revealed that repression of both endogenous and overexpressed VASP by RNA interference or by CRISPR/Cas9 reduced p8 transfer to the cell surface and to target Jurkat T-cells. Stable repression of VASP by RNA interference in chronically infected MT-2 cells impaired both p8 and HTLV-1 Gag transfer to target Jurkat T-cells, while virus release was unaffected. Thus, we identified VASP as a novel interaction partner of p8, which is important for transfer of HTLV-1 p8 and Gag to target T-cells.


Assuntos
Moléculas de Adesão Celular , Adesões Focais , Produtos do Gene gag , Vírus Linfotrópico T Tipo 1 Humano , Proteínas dos Microfilamentos , Fosfoproteínas , Linfócitos T , Moléculas de Adesão Celular/química , Moléculas de Adesão Celular/genética , Moléculas de Adesão Celular/metabolismo , Adesões Focais/química , Adesões Focais/genética , Adesões Focais/metabolismo , Adesões Focais/virologia , Produtos do Gene gag/química , Produtos do Gene gag/genética , Produtos do Gene gag/metabolismo , Vírus Linfotrópico T Tipo 1 Humano/química , Vírus Linfotrópico T Tipo 1 Humano/genética , Vírus Linfotrópico T Tipo 1 Humano/metabolismo , Humanos , Células Jurkat , Proteínas dos Microfilamentos/química , Proteínas dos Microfilamentos/genética , Proteínas dos Microfilamentos/metabolismo , Fosfoproteínas/química , Fosfoproteínas/genética , Fosfoproteínas/metabolismo , Domínios Proteicos , Linfócitos T/química , Linfócitos T/metabolismo , Linfócitos T/virologia
2.
Mol Cell ; 80(1): 164-174.e4, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-32877642

RESUMO

SARS-CoV-2 infections are rapidly spreading around the globe. The rapid development of therapies is of major importance. However, our lack of understanding of the molecular processes and host cell signaling events underlying SARS-CoV-2 infection hinders therapy development. We use a SARS-CoV-2 infection system in permissible human cells to study signaling changes by phosphoproteomics. We identify viral protein phosphorylation and define phosphorylation-driven host cell signaling changes upon infection. Growth factor receptor (GFR) signaling and downstream pathways are activated. Drug-protein network analyses revealed GFR signaling as key pathways targetable by approved drugs. The inhibition of GFR downstream signaling by five compounds prevents SARS-CoV-2 replication in cells, assessed by cytopathic effect, viral dsRNA production, and viral RNA release into the supernatant. This study describes host cell signaling events upon SARS-CoV-2 infection and reveals GFR signaling as a central pathway essential for SARS-CoV-2 replication. It provides novel strategies for COVID-19 treatment.


Assuntos
Antivirais/uso terapêutico , Betacoronavirus/efeitos dos fármacos , Proteínas Quinases Ativadas por Mitógeno/genética , Fosfatidilinositol 3-Quinase/genética , Receptores de Fatores de Crescimento/genética , Proteínas Virais/genética , Corticosteroides/uso terapêutico , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Anticorpos Neutralizantes/uso terapêutico , Betacoronavirus/imunologia , Betacoronavirus/patogenicidade , Células CACO-2 , Regulação da Expressão Gênica , Interações Hospedeiro-Patógeno/efeitos dos fármacos , Interações Hospedeiro-Patógeno/genética , Humanos , Proteínas Quinases Ativadas por Mitógeno/antagonistas & inibidores , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Fosfatidilinositol 3-Quinase/metabolismo , Fosfoproteínas/antagonistas & inibidores , Fosfoproteínas/genética , Fosfoproteínas/metabolismo , Fosforilação , Receptores de Fatores de Crescimento/antagonistas & inibidores , Receptores de Fatores de Crescimento/metabolismo , Transdução de Sinais , Proteínas Virais/antagonistas & inibidores , Proteínas Virais/metabolismo , Replicação Viral/efeitos dos fármacos
3.
PLoS Genet ; 16(8): e1008965, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32760058

RESUMO

The mobilizable resistance island Salmonella genomic island 1 (SGI1) is specifically mobilized by IncA and IncC conjugative plasmids. SGI1, its variants and IncC plasmids propagate multidrug resistance in pathogenic enterobacteria such as Salmonella enterica serovars and Proteus mirabilis. SGI1 modifies and uses the conjugation apparatus encoded by the helper IncC plasmid, thus enhancing its own propagation. Remarkably, although SGI1 needs a coresident IncC plasmid to excise from the chromosome and transfer to a new host, these elements have been reported to be incompatible. Here, the stability of SGI1 and its helper IncC plasmid, each expressing a different fluorescent reporter protein, was monitored using fluorescence-activated cell sorting (FACS). Without selective pressure, 95% of the cells segregated into two subpopulations containing either SGI1 or the helper plasmid. Furthermore, FACS analysis revealed a high level of SGI1-specific fluorescence in IncC+ cells, suggesting that SGI1 undergoes active replication in the presence of the helper plasmid. SGI1 replication was confirmed by quantitative PCR assays, and extraction and restriction of its plasmid form. Deletion of genes involved in SGI1 excision from the chromosome allowed a stable coexistence of SGI1 with its helper plasmid without selective pressure. In addition, deletion of S003 (rep) or of a downstream putative iteron-based origin of replication, while allowing SGI1 excision, abolished its replication, alleviated the incompatibility with the helper plasmid and enabled its cotransfer to a new host. Like SGI1 excision functions, rep expression was found to be controlled by AcaCD, the master activator of IncC plasmid transfer. Transient SGI1 replication seems to be a key feature of the life cycle of this family of genomic islands. Sequence database analysis revealed that SGI1 variants encode either a replication initiator protein with a RepA_C domain, or an alternative replication protein with N-terminal replicase and primase C terminal 1 domains.


Assuntos
Proteínas de Bactérias/genética , Conjugação Genética/genética , Ilhas Genômicas/genética , Fosfoproteínas/genética , Plasmídeos/genética , Antibacterianos/farmacologia , Cromossomos/efeitos dos fármacos , Cromossomos/genética , DNA Helicases/genética , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Farmacorresistência Bacteriana Múltipla/genética , Plasmídeos/efeitos dos fármacos , Proteus mirabilis/genética , Salmonella enterica/genética , Transativadores/genética
4.
Proc Natl Acad Sci U S A ; 117(32): 19475-19486, 2020 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-32709741

RESUMO

The DNA sensor cGAS catalyzes the production of the cyclic dinucleotide cGAMP, resulting in type I interferon responses. We addressed the functionality of cGAS-mediated DNA sensing in human and murine T cells. Activated primary CD4+ T cells expressed cGAS and responded to plasmid DNA by upregulation of ISGs and release of bioactive interferon. In mouse T cells, cGAS KO ablated sensing of plasmid DNA, and TREX1 KO enabled cells to sense short immunostimulatory DNA. Expression of IFIT1 and MX2 was downregulated and upregulated in cGAS KO and TREX1 KO T cell lines, respectively, compared to parental cells. Despite their intact cGAS sensing pathway, human CD4+ T cells failed to mount a reverse transcriptase (RT) inhibitor-sensitive immune response following HIV-1 infection. In contrast, infection of human T cells with HSV-1 that is functionally deficient for the cGAS antagonist pUL41 (HSV-1ΔUL41N) resulted in a cGAS-dependent type I interferon response. In accordance with our results in primary CD4+ T cells, plasmid challenge or HSV-1ΔUL41N inoculation of T cell lines provoked an entirely cGAS-dependent type I interferon response, including IRF3 phosphorylation and expression of ISGs. In contrast, no RT-dependent interferon response was detected following transduction of T cell lines with VSV-G-pseudotyped lentiviral or gammaretroviral particles. Together, T cells are capable to raise a cGAS-dependent cell-intrinsic response to both plasmid DNA challenge or inoculation with HSV-1ΔUL41N. However, HIV-1 infection does not appear to trigger cGAS-mediated sensing of viral DNA in T cells, possibly by revealing viral DNA of insufficient quantity, length, and/or accessibility to cGAS.


Assuntos
Linfócitos T CD4-Positivos/virologia , HIV-1/fisiologia , Interferon Tipo I/metabolismo , Nucleotidiltransferases/metabolismo , Animais , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Células Cultivadas , DNA Viral/fisiologia , Exodesoxirribonucleases/genética , Exodesoxirribonucleases/metabolismo , Herpesvirus Humano 1/fisiologia , Interações Hospedeiro-Patógeno , Humanos , Imunidade Inata , Fator Regulador 3 de Interferon/metabolismo , Camundongos , Nucleotidiltransferases/genética , Fosfoproteínas/genética , Fosfoproteínas/metabolismo , Fosforilação , Especificidade da Espécie , Replicação Viral
5.
PLoS Genet ; 16(7): e1008610, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32716926

RESUMO

Two-component systems and phosphorelays play central roles in the ability of bacteria to rapidly respond to changing environments. In E. coli and related enterobacteria, the complex Rcs phosphorelay is a critical player in the bacterial response to antimicrobial peptides, beta-lactam antibiotics, and other disruptions at the cell surface. The Rcs system is unusual in that an inner membrane protein, IgaA, is essential due to its negative regulation of the RcsC/RcsD/RcsB phosphorelay. While it is known that IgaA transduces signals from the outer membrane lipoprotein RcsF, how it interacts with the phosphorelay has remained unknown. Here we performed in vivo interaction assays and genetic dissection of the critical proteins and found that IgaA interacts with the phosphorelay protein RcsD, and that this interaction is necessary for regulation. Interactions between IgaA and RcsD within their respective periplasmic domains of these two proteins anchor repression of signaling. However, the signaling response depends on a second interaction between cytoplasmic loop 1 of IgaA and a truncated Per-Arndt-Sim (PAS-like) domain in RcsD. A single point mutation in the PAS-like domain increased interactions between the two proteins and blocked induction of the phosphorelay. IgaA may regulate RcsC, the histidine kinase that initiates phosphotransfer through the phosphorelay, indirectly, via its contacts with RcsD. Unlike RcsD, and unlike many other histidine kinases, the periplasmic domain of RcsC is dispensable for the response to signals that induce the Rcs phosphorelay system. The multiple contacts between IgaA and RcsD constitute a poised sensing system, preventing potentially toxic over-activation of this phosphorelay while enabling it to rapidly and quantitatively respond to signals.


Assuntos
Proteínas de Escherichia coli/genética , Proteínas de Membrana/genética , Fosfoproteínas/genética , Fosfotransferases/genética , Escherichia coli/genética , Regulação Bacteriana da Expressão Gênica/genética , Complexos Multienzimáticos/genética , Fosforilação/genética , Transporte Proteico/genética , Salmonella typhimurium/genética , Transdução de Sinais/genética
6.
Nucleic Acids Res ; 48(15): 8332-8348, 2020 09 04.
Artigo em Inglês | MEDLINE | ID: mdl-32633757

RESUMO

Negative cofactor 2 (NC2), including two subunits NC2α and NC2ß, is a conserved positive/negative regulator of class II gene transcription in eukaryotes. It is known that NC2 functions by regulating the assembly of the transcription preinitiation complex. However, the exact role of NC2 in transcriptional regulation is still unclear. Here, we reveal that, in Neurospora crassa, NC2 activates catalase-3 (cat-3) gene transcription in the form of heterodimer mediated by histone fold (HF) domains of two subunits. Deletion of HF domain in either of two subunits disrupts the NC2α-NC2ß interaction and the binding of intact NC2 heterodimer to cat-3 locus. Loss of NC2 dramatically increases histone variant H2A.Z deposition at cat-3 locus. Further studies show that NC2 recruits chromatin remodeling complex INO80C to remove H2A.Z from the nucleosomes around cat-3 locus, resulting in transcriptional activation of cat-3. Besides HF domains of two subunits, interestingly, C-terminal repression domain of NC2ß is required not only for NC2 binding to cat-3 locus, but also for the recruitment of INO80C to cat-3 locus and removal of H2A.Z from the nucleosomes. Collectively, our findings reveal a novel mechanism of NC2 in transcription activation through recruiting INO80C to remove H2A.Z from special H2A.Z-containing nucleosomes.


Assuntos
Catalase/genética , Fosfoproteínas/genética , Fatores de Transcrição/genética , Transcrição Genética , Núcleo Celular/genética , Montagem e Desmontagem da Cromatina/genética , Regulação da Expressão Gênica/genética , Genes MHC da Classe II/genética , Histonas/genética , Neurospora crassa/genética , Nucleossomos/genética , Nucleossomos/ultraestrutura , Fosfoproteínas/ultraestrutura , Ligação Proteica/genética , Fatores de Transcrição/ultraestrutura , Ativação Transcricional/genética
7.
Proc Natl Acad Sci U S A ; 117(31): 18401-18411, 2020 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-32690709

RESUMO

Disparities in cancer patient responses have prompted widespread searches to identify differences in sensitive vs. nonsensitive populations and form the basis of personalized medicine. This customized approach is dependent upon the development of pathway-specific therapeutics in conjunction with biomarkers that predict patient responses. Here, we show that Cdk5 drives growth in subgroups of patients with multiple types of neuroendocrine neoplasms. Phosphoproteomics and high throughput screening identified phosphorylation sites downstream of Cdk5. These phosphorylation events serve as biomarkers and effectively pinpoint Cdk5-driven tumors. Toward achieving targeted therapy, we demonstrate that mouse models of neuroendocrine cancer are responsive to selective Cdk5 inhibitors and biomimetic nanoparticles are effective vehicles for enhanced tumor targeting and reduction of drug toxicity. Finally, we show that biomarkers of Cdk5-dependent tumors effectively predict response to anti-Cdk5 therapy in patient-derived xenografts. Thus, a phosphoprotein-based diagnostic assay combined with Cdk5-targeted therapy is a rational treatment approach for neuroendocrine malignancies.


Assuntos
Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Tumores Neuroectodérmicos/tratamento farmacológico , Fosfoproteínas/metabolismo , Inibidores de Proteínas Quinases/administração & dosagem , Animais , Biomarcadores/análise , Biomarcadores/metabolismo , Quinase 5 Dependente de Ciclina/antagonistas & inibidores , Quinase 5 Dependente de Ciclina/genética , Quinase 5 Dependente de Ciclina/metabolismo , Xenoenxertos , Humanos , Camundongos , Neoplasias/genética , Tumores Neuroectodérmicos/genética , Tumores Neuroectodérmicos/metabolismo , Fosfoproteínas/análise , Fosfoproteínas/genética , Fosforilação
8.
Nat Commun ; 11(1): 2710, 2020 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-32483184

RESUMO

Most organisms on the earth exhibit circadian rhythms in behavior and physiology, which are driven by endogenous clocks. Phosphorylation plays a central role in timing the clock, but how this contributes to overt rhythms is unclear. Here we conduct phosphoproteomics in conjunction with transcriptomic and proteomic profiling using fly heads. By developing a pipeline for integrating multi-omics data, we identify 789 (~17%) phosphorylation sites with circadian oscillations. We predict 27 potential circadian kinases to participate in phosphorylating these sites, including 7 previously known to function in the clock. We screen the remaining 20 kinases for effects on circadian rhythms and find an additional 3 to be involved in regulating locomotor rhythm. We re-construct a signal web that includes the 10 circadian kinases and identify GASKET as a potentially important regulator. Taken together, we uncover a circadian kinome that potentially shapes the temporal pattern of the entire circadian molecular landscapes.


Assuntos
Ritmo Circadiano , Proteínas de Drosophila/metabolismo , Perfilação da Expressão Gênica/métodos , Fosfoproteínas/metabolismo , Fosfotransferases/metabolismo , Proteômica/métodos , Algoritmos , Animais , Cromatografia Líquida/métodos , Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Redes Reguladoras de Genes , Fosfoproteínas/genética , Fosforilação , Fosfotransferases/genética , Especificidade por Substrato , Espectrometria de Massas em Tandem/métodos
9.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 55(6): 394-401, 2020 Jun 09.
Artigo em Chinês | MEDLINE | ID: mdl-32486569

RESUMO

Objective: To choose a suitable efficient concentration of adenosine triphosphate (ATP) which can induce human dental pulp cells (HDPC) differentiate into odontoblast successfully, and explore the role of this concentration of ATP in dentin regeneration in vivo. Methods: HDPC were treated with different concentrations (0, 10, 400, 600, 800 µmol/L) of ATP. Then cell counting kit-8 (CCK-8), quantitative real-time PCR, and Western blotting were used to detect the cell proliferation and the expressions of odontoblastic differentiation related markers, dentin matrix protein 1 (DMP1) and dentin sialophosphoprotein (DSPP). Alizarin red S staining experiment was used to analyze the effect of ATP on the mineralization ability of HDPC. By the above experiments, the suitable effective concentration of ATP was chosen to pretreat the HDPC for 7 days, then cells were seeded on gelfoam, inserted into the root canal fragment, and subsequently transplanted into the subcutaneous space on the back of immunodeficient mice, after three months, the samples were stained with HE for histological analysis. Results: The CCK-8 results in 5 d showed that 10 µmol/L ATP obviously promoted the proliferation of HDPC, while the 600 and 800 µmol/L ATP apparently inhibited the HDPC proliferation, however, the proliferation in 800 µmol/L ATP group was lower than that of 600 µmol/L ATP group (P<0.05). qPCR and Western blotting results showed that the 600 and 800 µmol/L ATP significantly up-regulated the DMP1 and DSPP expressions (P<0.05), furthermore, there was no significant difference in the two groups, but no changes were found in other groups (P>0.05). After 21 days of culturing, there were obvious mineralization nodules in 600 and 800 µmol/L ATP groups, but no mineralization nodules in other groups. Quantitative analysis of the staining results showed the A value in 0, 10, 400, 600, and 800 µmol/L ATP groups were respectively 1.05±0.15, 1.11±0.23, 1.15±0.17, 3.65±0.30, and 3.40±0.43, and the A value in 600 and 800 µmol/L ATP groups were higher than those of other groups; however, there was no difference in 600 and 800 µmol/L ATP groups. The histological analysis showed that 600 µmol/L ATP could induce the HDPC differentiate into dentin-like structure in the root canal fragment. Conclusions: Therefore, the suitable effective concentration of ATP is 600 µmol/L, which could induce HDPC differentiate into odontoblast-like cells, and form the dentin-like structure in vivo.


Assuntos
Trifosfato de Adenosina , Polpa Dentária , Animais , Diferenciação Celular , Proliferação de Células , Células Cultivadas , Proteínas da Matriz Extracelular , Humanos , Camundongos , Odontoblastos , Fosfoproteínas/genética
10.
Mol Cell ; 78(4): 624-640.e7, 2020 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-32380061

RESUMO

The primary interactions between incoming viral RNA genomes and host proteins are crucial to infection and immunity. Until now, the ability to study these events was lacking. We developed viral cross-linking and solid-phase purification (VIR-CLASP) to characterize the earliest interactions between viral RNA and cellular proteins. We investigated the infection of human cells using Chikungunya virus (CHIKV) and influenza A virus and identified hundreds of direct RNA-protein interactions. Here, we explore the biological impact of three protein classes that bind CHIKV RNA within minutes of infection. We find CHIKV RNA binds and hijacks the lipid-modifying enzyme fatty acid synthase (FASN) for pro-viral activity. We show that CHIKV genomes are N6-methyladenosine modified, and YTHDF1 binds and suppresses CHIKV replication. Finally, we find that the innate immune DNA sensor IFI16 associates with CHIKV RNA, reducing viral replication and maturation. Our findings have direct applicability to the investigation of potentially all RNA viruses.


Assuntos
Febre de Chikungunya/virologia , Vírus Chikungunya/fisiologia , Ácido Graxo Sintase Tipo I/metabolismo , Genoma Viral , Proteínas Nucleares/metabolismo , Fosfoproteínas/metabolismo , Proteínas de Ligação a RNA/metabolismo , Replicação Viral , Animais , Febre de Chikungunya/genética , Febre de Chikungunya/metabolismo , Chlorocebus aethiops , Ácido Graxo Sintase Tipo I/genética , Células HEK293 , Humanos , Proteínas Nucleares/genética , Fosfoproteínas/genética , RNA Viral/genética , Proteínas de Ligação a RNA/genética , Células Vero
11.
Nat Commun ; 11(1): 2506, 2020 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-32427851

RESUMO

The genetic basis and corresponding clinical relevance of prolactinomas remain poorly understood. Here, we perform whole genome sequencing (WGS) on 21 patients with prolactinomas to detect somatic mutations and then validate the mutations with digital polymerase chain reaction (PCR) analysis of tissue samples from 227 prolactinomas. We identify the same hotspot somatic mutation in splicing factor 3 subunit B1 (SF3B1R625H) in 19.8% of prolactinomas. These patients with mutant prolactinomas display higher prolactin (PRL) levels (p = 0.02) and shorter progression-free survival (PFS) (p = 0.02) compared to patients without the mutation. Moreover, we identify that the SF3B1R625H mutation causes aberrant splicing of estrogen related receptor gamma (ESRRG), which results in stronger binding of pituitary-specific positive transcription factor 1 (Pit-1), leading to excessive PRL secretion. Thus our study validates an important mutation and elucidates a potential mechanism underlying the pathogenesis of prolactinomas that may lead to the development of targeted therapeutics.


Assuntos
Fosfoproteínas/genética , Prolactinoma/genética , Fatores de Processamento de RNA/genética , Adulto , Feminino , Humanos , Masculino , Mutação , Fosfoproteínas/metabolismo , Intervalo Livre de Progressão , Prolactina/genética , Prolactina/metabolismo , Prolactinoma/metabolismo , Prolactinoma/mortalidade , Fatores de Processamento de RNA/metabolismo , Receptores Estrogênicos/genética , Receptores Estrogênicos/metabolismo , Fator de Transcrição Pit-1/genética , Fator de Transcrição Pit-1/metabolismo , Adulto Jovem
12.
Anticancer Res ; 40(4): 1973-1979, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32234886

RESUMO

BACKGROUND/AIM: The aim of this study was to analyze the expression of nucleolin (NCL) and nucleophosmin (NPM) in prostate adenocarcinoma and in its loco-regional spread in the form of seminal vesicle invasion (SVI). MATERIALS AND METHODS: The study was performed on tissue microarrays of 40 cases of Gleason 3+4 pT3b prostate cancers including tissue samples from SVI. The expression of NCL and NPM was detected immunohistochemically and analyzed with image analysis software. RESULTS: The expression of NCL and NPM were higher in cancer cells within a prostate gland than in SVI. Gleason 4 pattern showed higher expression of NPM than Gleason 3 pattern cells. CONCLUSION: Differences in nuclear NCL and NPM expression in cancer cells between the prostate gland and SVI may indicate involvement of these proteins in loco-regional spread of adenocarcinoma of the prostate. Differences in NPM expression in Gleason 3 and Gleason 4 pattern suggest involvement of this protein in the differentiation of prostate cancer.


Assuntos
Adenocarcinoma/genética , Proteínas Nucleares/genética , Fosfoproteínas/genética , Neoplasias da Próstata/genética , Proteínas de Ligação a RNA/genética , Glândulas Seminais/patologia , Adenocarcinoma/epidemiologia , Adenocarcinoma/patologia , Idoso , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Invasividade Neoplásica/genética , Invasividade Neoplásica/patologia , Prognóstico , Próstata/patologia , Antígeno Prostático Específico/genética , Prostatectomia , Neoplasias da Próstata/epidemiologia , Neoplasias da Próstata/patologia
13.
PLoS One ; 15(4): e0229315, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32320410

RESUMO

Mutations in the splicing machinery have been implicated in a number of human diseases. Most notably, the U2 small nuclear ribonucleoprotein (snRNP) component SF3b1 has been found to be frequently mutated in blood cancers such as myelodysplastic syndromes (MDS). SF3b1 is a highly conserved HEAT repeat (HR)-containing protein and most of these blood cancer mutations cluster in a hot spot located in HR4-8. Recently, a second mutational hotspot has been identified in SF3b1 located in HR9-12 and is associated with acute myeloid leukemias, bladder urothelial carcinomas, and uterine corpus endometrial carcinomas. The consequences of these mutations on SF3b1 functions during splicing have not yet been tested. We incorporated the corresponding mutations into the yeast homolog of SF3b1 and tested their impact on splicing. We find that all of these HR9-12 mutations can support splicing in yeast, and this suggests that none of them are loss of function alleles in humans. The Hsh155V502F mutation alters splicing of several pre-mRNA reporters containing weak branch sites as well as a genetic interaction with Prp2 and physical interactions with Prp5 and Prp3. The ability of a single allele of Hsh155 to perturb interactions with multiple factors functioning at different stages of the splicing reaction suggests that some SF3b1-mutant disease phenotypes may have a complex origin on the spliceosome.


Assuntos
Mutação/genética , Fosfoproteínas/genética , Precursores de RNA/genética , Fatores de Processamento de RNA/genética , Processamento de RNA/genética , Sequências Repetitivas de Aminoácidos , Ribonucleoproteína Nuclear Pequena U2/genética , Proteínas de Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/genética , Sequência de Aminoácidos , Sequência Consenso/genética , Epistasia Genética , Humanos , Fosfoproteínas/química , Ligação Proteica , Fatores de Processamento de RNA/química , Ribonucleoproteína Nuclear Pequena U2/química , Saccharomyces cerevisiae/crescimento & desenvolvimento , Proteínas de Saccharomyces cerevisiae/química
14.
Proc Natl Acad Sci U S A ; 117(19): 10305-10312, 2020 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-32332164

RESUMO

The gene encoding the core spliceosomal protein SF3B1 is the most frequently mutated gene encoding a splicing factor in a variety of hematologic malignancies and solid tumors. SF3B1 mutations induce use of cryptic 3' splice sites (3'ss), and these splicing errors contribute to tumorigenesis. However, it is unclear how widespread this type of cryptic 3'ss usage is in cancers and what is the full spectrum of genetic mutations that cause such missplicing. To address this issue, we performed an unbiased pan-cancer analysis to identify genetic alterations that lead to the same aberrant splicing as observed with SF3B1 mutations. This analysis identified multiple mutations in another spliceosomal gene, SUGP1, that correlated with significant usage of cryptic 3'ss known to be utilized in mutant SF3B1 expressing cells. Remarkably, this is consistent with recent biochemical studies that identified a defective interaction between mutant SF3B1 and SUGP1 as the molecular defect responsible for cryptic 3'ss usage. Experimental validation revealed that five different SUGP1 mutations completely or partially recapitulated the 3'ss defects. Our analysis suggests that SUGP1 mutations in cancers can induce missplicing identical or similar to that observed in mutant SF3B1 cancers.


Assuntos
Biologia Computacional/métodos , Mutação , Neoplasias/genética , Fosfoproteínas/genética , Sítios de Splice de RNA , Fatores de Processamento de RNA/genética , Processamento de RNA , Análise Mutacional de DNA , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias/patologia , Spliceossomos
15.
Science ; 368(6488)2020 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-32299917

RESUMO

The chromosome breakage-fusion-bridge (BFB) cycle is a mutational process that produces gene amplification and genome instability. Signatures of BFB cycles can be observed in cancer genomes alongside chromothripsis, another catastrophic mutational phenomenon. We explain this association by elucidating a mutational cascade that is triggered by a single cell division error-chromosome bridge formation-that rapidly increases genomic complexity. We show that actomyosin forces are required for initial bridge breakage. Chromothripsis accumulates, beginning with aberrant interphase replication of bridge DNA. A subsequent burst of DNA replication in the next mitosis generates extensive DNA damage. During this second cell division, broken bridge chromosomes frequently missegregate and form micronuclei, promoting additional chromothripsis. We propose that iterations of this mutational cascade generate the continuing evolution and subclonal heterogeneity characteristic of many human cancers.


Assuntos
Carcinogênese/genética , Carcinogênese/patologia , Quebra Cromossômica , Dano ao DNA/genética , Mitose/genética , Neoplasias/genética , Neoplasias/patologia , Actomiosina/metabolismo , Linhagem Celular Tumoral , Exodesoxirribonucleases/genética , Dosagem de Genes , Genoma Humano , Humanos , Fenômenos Mecânicos , Mutagênese , Mutação , Fosfoproteínas/genética , Análise de Célula Única
16.
PLoS Comput Biol ; 16(4): e1007750, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32251432

RESUMO

In multicellular organisms, the timing and placement of gene expression in a developing tissue assigns the fate of each cell in the embryo in order for a uniform field of cells to differentiate into a reproducible pattern of organs and tissues. This positional information is often achieved through the action of spatial gradients of morphogens. Spatial patterns of gene expression are paradoxically robust to variations in morphogen dosage, given that, by definition, gene expression must be sensitive to morphogen concentration. In this work we investigate the robustness of the Dorsal/NF-κB signaling module with respect to perturbations to the dosage of maternally-expressed dorsal mRNA. The Dorsal morphogen gradient patterns the dorsal-ventral axis of the early Drosophila embryo, and we found that an empirical description of the Dorsal gradient is highly sensitive to maternal dorsal dosage. In contrast, we found experimentally that gene expression patterns are highly robust. Although the components of this signaling module have been characterized in detail, how their function is integrated to produce robust gene expression patterns to variations in the dorsal maternal dosage is still unclear. Therefore, we analyzed a mechanistic model of the Dorsal signaling module and found that Cactus, a cytoplasmic inhibitor for Dorsal, must be present in the nucleus for the system to be robust. Furthermore, active Toll, the receptor that dissociates Cactus from Dorsal, must be saturated. Finally, the vast majority of robust descriptions of the system require facilitated diffusion of Dorsal by Cactus. Each of these three recently-discovered mechanisms of the Dorsal module are critical for robustness. These mechanisms synergistically contribute to changing the amplitude and shape of the active Dorsal gradient, which is required for robust gene expression. Our work highlights the need for quantitative understanding of biophysical mechanisms of morphogen gradients in order to understand emergent phenotypes, such as robustness.


Assuntos
Padronização Corporal/genética , Proteínas de Drosophila/genética , Proteínas Nucleares/genética , Fosfoproteínas/genética , Fatores de Transcrição/genética , Animais , Núcleo Celular/metabolismo , Citoplasma/metabolismo , Proteínas de Ligação a DNA/metabolismo , Drosophila/embriologia , Drosophila/genética , Proteínas de Drosophila/metabolismo , Embrião não Mamífero/metabolismo , Regulação da Expressão Gênica no Desenvolvimento/genética , Morfogênese/genética , NF-kappa B/metabolismo , Proteínas Nucleares/metabolismo , Fosfoproteínas/metabolismo , Transdução de Sinais , Fatores de Transcrição/metabolismo
17.
Nat Cell Biol ; 22(4): 372-379, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32231306

RESUMO

The availability of nucleotides has a direct impact on transcription. The inhibition of dihydroorotate dehydrogenase (DHODH) with leflunomide impacts nucleotide pools by reducing pyrimidine levels. Leflunomide abrogates the effective transcription elongation of genes required for neural crest development and melanoma growth in vivo1. To define the mechanism of action, we undertook an in vivo chemical suppressor screen for restoration of neural crest after leflunomide treatment. Surprisingly, we found that alterations in progesterone and progesterone receptor (Pgr) signalling strongly suppressed leflunomide-mediated neural crest effects in zebrafish. In addition, progesterone bypasses the transcriptional elongation block resulting from Paf complex deficiency, rescuing neural crest defects in ctr9 morphant and paf1(alnz24) mutant embryos. Using proteomics, we found that Pgr binds the RNA helicase protein Ddx21. ddx21-deficient zebrafish show resistance to leflunomide-induced stress. At a molecular level, nucleotide depletion reduced the chromatin occupancy of DDX21 in human A375 melanoma cells. Nucleotide supplementation reversed the gene expression signature and DDX21 occupancy changes prompted by leflunomide. Together, our results show that DDX21 acts as a sensor and mediator of transcription during nucleotide stress.


Assuntos
RNA Helicases DEAD-box/genética , Melanócitos/metabolismo , Crista Neural/metabolismo , Oxirredutases atuantes sobre Doadores de Grupo CH-CH/genética , Receptores de Progesterona/genética , Proteínas de Peixe-Zebra/genética , Animais , Linhagem Celular Tumoral , RNA Helicases DEAD-box/metabolismo , Embrião não Mamífero , Regulação da Expressão Gênica no Desenvolvimento , Humanos , Leflunomida/farmacologia , Melanócitos/efeitos dos fármacos , Melanócitos/patologia , Crista Neural/efeitos dos fármacos , Crista Neural/crescimento & desenvolvimento , Nucleotídeos , Oxirredutases atuantes sobre Doadores de Grupo CH-CH/metabolismo , Fosfoproteínas/genética , Fosfoproteínas/metabolismo , Progesterona/metabolismo , Ligação Proteica , Receptores de Progesterona/metabolismo , Transdução de Sinais , Estresse Fisiológico/genética , Elongação da Transcrição Genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Peixe-Zebra/embriologia , Peixe-Zebra/genética , Peixe-Zebra/metabolismo , Proteínas de Peixe-Zebra/metabolismo
18.
Hum Genet ; 139(10): 1261-1272, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32318854

RESUMO

Nonsyndromic cleft lip with or without cleft palate (NSCLP) is a common birth defect for which only ~ 20% of the underlying genetic variation has been identified. Variants in noncoding regions have been increasingly suggested to contribute to the missing heritability. In this study, we investigated whether variation in craniofacial enhancers contributes to NSCLP. Candidate enhancers were identified using VISTA Enhancer Browser and previous publications. Prioritization was based on patterning defects in knockout mice, deletion/duplication of craniofacial genes in animal models and results of whole exome/whole genome sequencing studies. This resulted in 20 craniofacial enhancers to be investigated. Custom amplicon-based sequencing probes were designed and used for sequencing 380 NSCLP probands (from multiplex and simplex families of non-Hispanic white (NHW) and Hispanic ethnicities) using Illumina MiSeq. The frequencies of identified variants were compared to ethnically matched European (CEU) and Los Angeles Mexican (MXL) control genomes and used for association analyses. Variants in mm427/MSX1 and hs1582/SPRY1 showed genome-wide significant association with NSCLP (p ≤ 6.4 × 10-11). In silico analysis showed that these enhancer variants may disrupt important transcription factor binding sites. Haplotypes involving these enhancers and also mm435/ABCA4 were significantly associated with NSCLP, especially in NHW (p ≤ 6.3 × 10-7). Importantly, groupwise burden analysis showed several enhancer combinations significantly over-represented in NSCLP individuals, revealing novel NSCLP pathways and supporting a polygenic inheritance model. Our findings support the role of craniofacial enhancer sequence variation in the etiology of NSCLP.


Assuntos
Fenda Labial/genética , Fissura Palatina/genética , Elementos Facilitadores Genéticos , Predisposição Genética para Doença , Variação Genética , Herança Multifatorial , Transportadores de Cassetes de Ligação de ATP/genética , Animais , Doenças Assintomáticas , Fenda Labial/etnologia , Fenda Labial/patologia , Fissura Palatina/etnologia , Fissura Palatina/patologia , Embrião de Mamíferos , Grupo com Ancestrais do Continente Europeu , Feminino , Estudos de Associação Genética , Sequenciamento de Nucleotídeos em Larga Escala , Hispano-Americanos , Humanos , Fator de Transcrição MSX1/genética , Masculino , Proteínas de Membrana/genética , Camundongos , Linhagem , Fosfoproteínas/genética , Estados Unidos
19.
Artigo em Inglês | MEDLINE | ID: mdl-32293933

RESUMO

Na,K-ATPase is a membrane transporter that is critically important for skeletal muscle function. Mdx and Bla/J mice are the experimental models of Duchenne muscular dystrophy and dysferlinopathy that are known to differ in the molecular mechanism of the pathology. This study examines the function of α1- and α2-Na,K-ATPase isozymes in respiratory diaphragm and postural soleus muscles from mdx and Bla/J mice compared with control С57Bl/6 mice. In diaphragm muscles, the motor endplate structure was severely disturbed (manifested by defragmentation) in mdx mice only. The endplate membrane of both Bla/J and mdx mice was depolarized due to specific loss of the α2-Na,K-ATPase electrogenic activity and its decreased membrane abundance. Total FXYD1 subunit (modulates Na,K-ATPase activity) abundance was decreased in both mouse models. However, the α2-Na,K-ATPase protein content as well as mRNA expression were specifically and significantly reduced only in mdx mice. The endplate membrane cholesterol redistribution was most pronounced in mdx mice. Soleus muscles from Bla/J and mdx mice demonstrated reduction of the α2-Na,K-ATPase membrane abundance and mRNA expression similar to the diaphragm muscles. In contrast to diaphragm, the α2-Na,K-ATPase protein content was altered in both Bla/J and mdx mice; membrane cholesterol re-distribution was not observed. Thus, the α2-Na,K-ATPase is altered in both Bla/J and mdx mouse models of chronic muscle pathology. However, despite some similarities, the α2-Na,K-ATPase and cholesterol abnormalities are more pronounced in mdx mice.


Assuntos
Proteínas de Membrana/genética , Distrofias Musculares/genética , Fosfoproteínas/genética , ATPase Trocadora de Sódio-Potássio/genética , Animais , Membrana Celular/genética , Membrana Celular/metabolismo , Colesterol/genética , Colesterol/metabolismo , Modelos Animais de Doenças , Regulação da Expressão Gênica/genética , Humanos , Camundongos , Camundongos Endogâmicos mdx , Placa Motora/genética , Músculo Esquelético/metabolismo , Músculo Esquelético/patologia , Distrofias Musculares/metabolismo , Distrofias Musculares/patologia , Isoformas de Proteínas/genética , RNA Mensageiro/genética
20.
Am J Physiol Heart Circ Physiol ; 318(5): H1256-H1271, 2020 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-32223553

RESUMO

Despite decades of research on the pathophysiology of myocardial stunning, protein changes and/or phosphorylation status underlying alterations in cardiac function/structure remain inadequately understood. Here, we utilized comprehensive and quantitative proteomic and phosphoproteomic approaches to explore molecular mechanisms of myocardial stunning in swine. The closed-chest swine (n = 5 pigs) were subjected to a 10-min left anterior descending coronary artery (LAD) occlusion producing regional myocardial stunning. Tissues from the ischemic LAD region and a remote nonischemic area of the left ventricle were collected 1 h after reperfusion. Ion current-based proteomics (IonStar) and quantitative phosphoproteomics were employed in parallel to identify alterations in protein level and site-specific phosphorylation changes. A novel swine heart protein database exhibiting high accuracy and low redundancy was developed here to facilitate comprehensive study. Further informatic investigations identified potential protein-protein interactions in stunned myocardium. In total, we quantified 2,099 protein groups and 4,699 phosphorylation sites with only 0.4% missing values. Proteomic analyses revealed downregulation of contractile function and extracellular matrix remodeling. Meanwhile, alterations in phosphorylation linked with contractile dysfunction and apoptotic cell death were uncovered. NetworKIN/STRING analysis predicted regulatory kinases responsible for altered phosphosites, such as protein kinase C-mediated phosphorylation of cardiac troponin I-S199 and CaMKII-mediated phosphorylation of phospholamban-T17. In summary, the ion current-based proteomics and phosphoproteomics reliably identified novel alterations in protein content and phosphorylation contributing to contractile dysfunction, extracellular matrix (ECM) damage, and programmed cell death in stunned myocardium, which corroborate well with our physiological observations. Moreover, this work developed a comprehensive database of the swine heart proteome, a highly valuable resource for future translational research in porcine models with cardiovascular diseases.NEW & NOTEWORTHY We first used ion current-based proteomics and phosphoproteomics to reliably identify novel alterations in protein expression and phosphorylation contributing to contractile dysfunction, extracellular matrix (ECM) damage, and programmed cell death in stunned myocardium and developed a comprehensive swine heart-specific proteome database, which provides a valuable resource for future research in porcine models of cardiovascular diseases.


Assuntos
Doença das Coronárias/metabolismo , Miocárdio/metabolismo , Fosfoproteínas/metabolismo , Proteoma/metabolismo , Potenciais de Ação , Animais , Doença das Coronárias/genética , Doença das Coronárias/fisiopatologia , Masculino , Contração Miocárdica , Fosfoproteínas/genética , Proteínas Quinases/genética , Proteínas Quinases/metabolismo , Proteoma/genética , Suínos
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