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The optimal follow-up care for relapse detection in acute myeloid leukemia (AML) patients in first remission after consolidation therapy with intensive chemotherapy is not established. In this retrospective study, we evaluate the diagnostic value of an intensive relapse surveillance strategy by regular bone marrow aspirations (BMA) in these patients. We identified 86 patients with newly diagnosed non-promyelocytic AML who had reached complete remission (CR) after intensive induction and consolidation chemotherapy between 2007 and 2019. Annual relapse rates were 40%, 17%, and 2% in years 1-3, respectively. Patients in CR were surveilled by BMA scheduled every 3 months for 2 years, followed by BMA every 6 months. This surveillance regimen detected 29 of 55 relapses (53%), 11 of which were molecular relapses (20%). The remaining 26 of 55 relapses (47%) were diagnosed by non-surveillance BMA prompted by specific suspicion of relapse. Most patients showed concurrent morphological abnormalities in peripheral blood (PB) at time of relapse. Seven percent of all morphological relapses occurred without simultaneous PB abnormalities and would have been delayed without surveillance BMA. Intensified monthly PB assessment paired with BMA every 3 months during the first 2 years may be a highly sensitive relapse surveillance strategy.
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Medula Óssea , Leucemia Mieloide Aguda , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Humanos , Leucemia Mieloide Aguda/diagnóstico , Leucemia Mieloide Aguda/tratamento farmacológico , Recidiva , Indução de Remissão , Estudos RetrospectivosRESUMO
PURPOSE: Molecular diagnostics including next generation gene sequencing are increasingly used to determine options for individualized therapies in brain tumor patients. We aimed to evaluate the decision-making process of molecular targeted therapies and analyze data on tolerability as well as signals for efficacy. METHODS: Via retrospective analysis, we identified primary brain tumor patients who were treated off-label with a targeted therapy at the University Hospital Frankfurt, Goethe University. We analyzed which types of molecular alterations were utilized to guide molecular off-label therapies and the diagnostic procedures for their assessment during the period from 2008 to 2021. Data on tolerability and outcomes were collected. RESULTS: 413 off-label therapies were identified with an increasing annual number for the interval after 2016. 37 interventions (9%) were targeted therapies based on molecular markers. Glioma and meningioma were the most frequent entities treated with molecular matched targeted therapies. Rare entities comprised e.g. medulloblastoma and papillary craniopharyngeoma. Molecular targeted approaches included checkpoint inhibitors, inhibitors of mTOR, FGFR, ALK, MET, ROS1, PIK3CA, CDK4/6, BRAF/MEK and PARP. Responses in the first follow-up MRI were partial response (13.5%), stable disease (29.7%) and progressive disease (46.0%). There were no new safety signals. Adverse events with fatal outcome (CTCAE grade 5) were not observed. Only, two patients discontinued treatment due to side effects. Median progression-free and overall survival were 9.1/18 months in patients with at least stable disease, and 1.8/3.6 months in those with progressive disease at the first follow-up MRI. CONCLUSION: A broad range of actionable alterations was targeted with available molecular therapeutics. However, efficacy was largely observed in entities with paradigmatic oncogenic drivers, in particular with BRAF mutations. Further research on biomarker-informed molecular matched therapies is urgently necessary.
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Neoplasias Encefálicas , Terapia de Alvo Molecular , Humanos , Mutação , Proteínas Tirosina Quinases , Proteínas Proto-Oncogênicas , Proteínas Proto-Oncogênicas B-raf , Estudos RetrospectivosRESUMO
RNA metabolism is altered following DNA damage, but the underlying mechanisms are not well understood. Through a 14-3-3 interaction screen for DNA damage-induced protein interactions in human cells, we identified protein complexes connected to RNA biology. These include the nuclear exosome targeting (NEXT) complex that regulates turnover of noncoding RNAs termed promoter upstream transcripts (PROMPTs). We show that the NEXT subunit RBM7 is phosphorylated upon DNA damage by the MAPKAPK2 kinase and establish that this mediates 14-3-3 binding and decreases PROMPT binding. These findings and our observation that cells lacking RBM7 display DNA damage hypersensitivity link PROMPT turnover to the DNA damage response.
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Proteínas 14-3-3/metabolismo , Dano ao DNA/fisiologia , Complexo Multienzimático de Ribonucleases do Exossomo/metabolismo , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Sistema de Sinalização das MAP Quinases , Fosforilação , Ligação Proteica , Proteínas Serina-Treonina Quinases/metabolismo , RNA não Traduzido/metabolismo , Raios UltravioletaRESUMO
Kinase fusions are considered oncogenic drivers in numerous types of cancer. In lung adenocarcinoma 5-10% of patients harbor kinase fusions. The most frequently detected kinase fusion involves the Anaplastic Lymphoma Kinase (ALK) and Echinoderm Microtubule-associated protein-Like 4 (EML4). In addition, oncogenic kinase fusions involving the tyrosine kinases RET and ROS1 are found in smaller subsets of patients. In this study, we employed quantitative mass spectrometry-based phosphoproteomics to define the cellular tyrosine phosphorylation patterns induced by different oncogenic kinase fusions identified in patients with lung adenocarcinoma. We show that exogenous expression of the kinase fusions in HEK 293T cells leads to widespread tyrosine phosphorylation. Direct comparison of different kinase fusions demonstrates that the kinase part and not the fusion partner primarily defines the phosphorylation pattern. The tyrosine phosphorylation patterns differed between ALK, ROS1, and RET fusions, suggesting that oncogenic signaling induced by these kinases involves the modulation of different cellular processes.
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Adenocarcinoma de Pulmão , Neoplasias Pulmonares , Adenocarcinoma de Pulmão/genética , Humanos , Neoplasias Pulmonares/genética , Proteínas de Fusão Oncogênica/genética , Proteínas de Fusão Oncogênica/metabolismo , Fosforilação , Proteínas Tirosina Quinases/genética , Proteínas Tirosina Quinases/metabolismo , Proteômica , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas c-ret/metabolismo , TirosinaRESUMO
Treatment-related complications contribute substantially to morbidity and mortality in acute myeloid leukemia (AML) patients undergoing induction chemotherapy. Although AML patients are susceptible to fluid overload (FO) (e.g., in the context of chemotherapy protocols, during sepsis treatment or to prevent tumor lysis syndrome), little attention has been paid to its role in AML patients undergoing induction chemotherapy. AML patients receiving induction chemotherapy between 2014 and 2019 were included in this study. FO was defined as ≥5% weight gain on day 7 of induction chemotherapy compared to baseline weight determined on the day of admission. We found FO in 23 (12%) of 187 AML patients undergoing induction chemotherapy. Application of >100 ml crystalloid fluids/kg body weight until day 7 of induction chemotherapy was identified as an independent risk factor for FO. AML patients with FO suffered from a significantly increased 90-day mortality rate and FO was demonstrated as an independent risk factor for 90-day mortality. Our data suggests an individualized, weight-adjusted calculation of crystalloid fluids in order to prevent FO-related morbidity and mortality in AML patients during induction chemotherapy. Prospective trials are required to determine the adequate fluid management in this patient population.
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Quimioterapia de Indução/efeitos adversos , Leucemia Mieloide Aguda/terapia , Adulto , Idoso , Feminino , Humanos , Leucemia Mieloide Aguda/mortalidade , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Estudos Retrospectivos , Fatores de Risco , Adulto JovemRESUMO
Acute kidney injury (AKI) complicates the clinical course of hospitalized patients by increasing need for intensive care treatment and mortality. There is only little data about its impact on AML patients undergoing intensive induction chemotherapy. In this study, we analyzed the incidence as well as risk factors for AKI development and its impact on the clinical course of AML patients undergoing induction chemotherapy. We retrospectively analyzed data from 401 AML patients undergoing induction chemotherapy between 2007 and 2019. AKI was defined and stratified according to KIDGO criteria by referring to a defined baseline serum creatinine measured on day 1 of induction chemotherapy. Seventy-two of 401 (18%) AML patients suffered from AKI during induction chemotherapy. AML patients with AKI had more days with fever (7 vs. 5, p = 0.028) and were more often treated on intensive care unit (45.8% vs. 10.6%, p < 0.001). AML patients with AKI had a significantly lower complete remission rate after induction chemotherapy and, with 402 days, a significantly shorter median overall survival (OS) (median OS for AML patients without AKI not reached). In this study, we demonstrate that the KIDGO classification allows mortality risk stratification for AML patients undergoing induction chemotherapy. Relatively mild AKI episodes have impact on the clinical course of these patients and can lead to chronic impairment of kidney function. Therefore, we recommend incorporating risk factors for AKI in decision-making considering nutrition, fluid management, as well as the choice of potentially nephrotoxic medication in order to decrease the incidence of AKI.
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Injúria Renal Aguda/etiologia , Quimioterapia de Indução/efeitos adversos , Leucemia Mieloide Aguda/complicações , Leucemia Mieloide Aguda/tratamento farmacológico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Resultado do Tratamento , Adulto JovemRESUMO
Lysine acetylation is a frequently occurring posttranslational modification in bacteria; however, little is known about its origin and regulation. Using the model bacterium Escherichia coli (E. coli), we found that most acetylation occurred at a low level and accumulated in growth-arrested cells in a manner that depended on the formation of acetyl-phosphate (AcP) through glycolysis. Mutant cells unable to produce AcP had significantly reduced acetylation levels, while mutant cells unable to convert AcP to acetate had significantly elevated acetylation levels. We showed that AcP can chemically acetylate lysine residues in vitro and that AcP levels are correlated with acetylation levels in vivo, suggesting that AcP may acetylate proteins nonenzymatically in cells. These results uncover a critical role for AcP in bacterial acetylation and indicate that most acetylation in E. coli occurs at a low level and is dynamically affected by metabolism and cell proliferation in a global, uniform manner.
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Acetatos/metabolismo , Proliferação de Células , Escherichia coli/metabolismo , Lisina/química , Organofosfatos/metabolismo , Acetilação , Células Cultivadas , Cromatografia Líquida , Escherichia coli/genética , Escherichia coli/crescimento & desenvolvimento , Glicólise , Lisina/metabolismo , Mutação/genética , Processamento de Proteína Pós-Traducional , Espectrometria de Massas em TandemRESUMO
Conjugation of Met1-linked polyubiquitin (Met1-Ub) by the linear ubiquitin chain assembly complex (LUBAC) is an important regulatory modification in innate immune signaling. So far, only few Met1-Ub substrates have been described, and the regulatory mechanisms have remained elusive. We recently identified that the ovarian tumor (OTU) family deubiquitinase OTULIN specifically disassembles Met1-Ub. Here, we report that OTULIN is critical for limiting Met1-Ub accumulation after nucleotide-oligomerization domain-containing protein 2 (NOD2) stimulation, and that OTULIN depletion augments signaling downstream of NOD2. Affinity purification of Met1-Ub followed by quantitative proteomics uncovered RIPK2 as the predominant NOD2-regulated substrate. Accordingly, Met1-Ub on RIPK2 was largely inhibited by overexpressing OTULIN and was increased by OTULIN depletion. Intriguingly, OTULIN-depleted cells spontaneously accumulated Met1-Ub on LUBAC components, and NOD2 or TNFR1 stimulation led to extensive Met1-Ub accumulation on receptor complex components. We propose that OTULIN restricts Met1-Ub formation after immune receptor stimulation to prevent unwarranted proinflammatory signaling.
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Endopeptidases/fisiologia , Imunidade Inata , Metionina/metabolismo , Transdução de Sinais , Ubiquitinação , Expressão Gênica , Técnicas de Silenciamento de Genes , Células HEK293 , Humanos , Mediadores da Inflamação/metabolismo , NF-kappa B/metabolismo , Proteína Adaptadora de Sinalização NOD2/metabolismo , Mapeamento de Interação de Proteínas , Proteína Serina-Treonina Quinase 2 de Interação com Receptor/metabolismo , Proteínas Inibidoras de Apoptose Ligadas ao Cromossomo X/metabolismoRESUMO
In this work, we investigate the challenges public-sector organizations face when seeking to leverage prescriptive analytics and provide insights into the public value such data-driven tools and methods can provide. Using the strategic triangle of value, legitimacy, and operational capacity as a starting point, we derive a framework to assess public-sector prescriptive analytics initiatives, along with six guiding questions that structure the assessment process. We present a case study applying prescriptive analytics to the placement of charge points in urban areas, a critical challenge many municipalities are currently facing in the transition towards electric mobility. Reflecting on the analytics application as well as its development and implementation process through the guiding questions, we derive key lessons for public-sector organizations seeking to apply prescriptive analytics.
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TNF-α is a key regulator of innate immune and proinflammatory responses. However, the composition of the TNF-α receptor-associated signaling complexes (TNF-RSC) and the architecture of the downstream signaling networks are incompletely understood. We employed quantitative mass spectrometry to demonstrate that TNF-α stimulation induces widespread protein phosphorylation and that the scope of phosphorylation expands in a temporal manner. TNF-α stimulation also induces rapid ubiquitylation of components of the TNF-RSC Temporal analysis of the TNF-RSC composition identified SPATA2 as a novel component of the TNF-RSC The predicted PUB domain in the N-terminus of SPATA2 interacts with the USP domain of CYLD, whereas the C-terminus of SPATA2 interacts with HOIP SPATA2 is required for recruitment of CYLD to the TNF-RSC Downregulation of SPATA2 augments transcriptional activation of NF-κB and inhibits TNF-α-induced necroptosis, pointing to an important function of SPATA2 in modulating the outcomes of TNF-α signaling. Taken together, our study draws a detailed map of TNF-α signaling, identifies SPATA2 as a novel component of TNF-α signaling, and provides a rich resource for further functional investigations.
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Proteínas/metabolismo , Receptores do Fator de Necrose Tumoral/metabolismo , Transdução de Sinais , Fator de Necrose Tumoral alfa/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Linhagem Celular , Enzima Desubiquitinante CYLD , Humanos , Espectrometria de Massas , Fosforilação , Mapeamento de Interação de Proteínas , Processamento de Proteína Pós-Traducional , Proteoma/análise , Ubiquitina-Proteína Ligases/metabolismo , UbiquitinaçãoRESUMO
Valosin-containing protein (VCP) is an evolutionarily conserved ubiquitin-dependent ATPase that mediates the degradation of proteins through the ubiquitin-proteasome pathway. Despite the central role of VCP in the regulation of protein homeostasis, identity and nature of its cellular substrates remain poorly defined. Here, we combined chemical inhibition of VCP and quantitative ubiquitin remnant profiling to assess the effect of VCP inhibition on the ubiquitin-modified proteome and to probe the substrate spectrum of VCP in human cells. We demonstrate that inhibition of VCP perturbs cellular ubiquitylation and increases ubiquitylation of a different subset of proteins compared to proteasome inhibition. VCP inhibition globally upregulates K6-linked ubiquitylation that is dependent on the HECT-type ubiquitin E3 ligase HUWE1. We report ~450 putative VCP substrates, many of which function in nuclear processes, including gene expression, DNA repair and cell cycle. Moreover, we identify that VCP regulates the level and activity of the transcription factor c-Myc.
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Complexo de Endopeptidases do Proteassoma/metabolismo , Proteínas Proto-Oncogênicas c-myc/metabolismo , Proteína com Valosina/metabolismo , Linhagem Celular , Núcleo Celular/metabolismo , Humanos , Modelos Biológicos , Ligação Proteica , Mapeamento de Interação de Proteínas , Mapas de Interação de Proteínas , Transporte Proteico , Proteólise , Proteoma , Proteômica/métodos , UbiquitinaçãoRESUMO
The regulatory networks of the DNA damage response (DDR) encompass many proteins and posttranslational modifications. Here, we use mass spectrometry-based proteomics to analyze the systems-wide response to DNA damage by parallel quantification of the DDR-regulated phosphoproteome, acetylome, and proteome. We show that phosphorylation-dependent signaling networks are regulated more strongly compared to acetylation. Among the phosphorylated proteins identified are many putative substrates of DNA-PK, ATM, and ATR kinases, but a majority of phosphorylated proteins do not share the ATM/ATR/DNA-PK target consensus motif, suggesting an important role of downstream kinases in amplifying DDR signals. We show that the splicing-regulator phosphatase PPM1G is recruited to sites of DNA damage, while the splicing-associated protein THRAP3 is excluded from these regions. Moreover, THRAP3 depletion causes cellular hypersensitivity to DNA-damaging agents. Collectively, these data broaden our knowledge of DNA damage signaling networks and highlight an important link between RNA metabolism and DNA repair.
Assuntos
Dano ao DNA , Reparo do DNA , Proteínas de Ligação a DNA/fisiologia , Fatores de Transcrição/fisiologia , Linhagem Celular Tumoral , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Células HeLa , Humanos , Fosfoproteínas Fosfatases/fisiologia , Fosforilação , Proteína Fosfatase 2C , Proteômica , Transdução de Sinais , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Fator de Necrose Tumoral alfa/metabolismoRESUMO
Selective autophagy of damaged mitochondria requires autophagy receptors optineurin (OPTN), NDP52 (CALCOCO2), TAX1BP1, and p62 (SQSTM1) linking ubiquitinated cargo to autophagic membranes. By using quantitative proteomics, we show that Tank-binding kinase 1 (TBK1) phosphorylates all four receptors on several autophagy-relevant sites, including the ubiquitin- and LC3-binding domains of OPTN and p62/SQSTM1 as well as the SKICH domains of NDP52 and TAX1BP1. Constitutive interaction of TBK1 with OPTN and the ability of OPTN to bind to ubiquitin chains are essential for TBK1 recruitment and kinase activation on mitochondria. TBK1 in turn phosphorylates OPTN's UBAN domain at S473, thereby expanding the binding capacity of OPTN to diverse Ub chains. In combination with phosphorylation of S177 and S513, this posttranslational modification promotes recruitment and retention of OPTN/TBK1 on ubiquitinated, damaged mitochondria. Moreover, phosphorylation of OPTN on S473 enables binding to pS65 Ub chains and is also implicated in PINK1-driven and Parkin-independent mitophagy. Thus, TBK1-mediated phosphorylation of autophagy receptors creates a signal amplification loop operating in selective autophagy of damaged mitochondria.
Assuntos
Autofagia , Mitocôndrias/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Fator de Transcrição TFIIIA/metabolismo , Proteínas de Ciclo Celular , Células HeLa , Humanos , Proteínas de Membrana Transportadoras , Fosforilação , Ligação Proteica , Ubiquitina/metabolismoRESUMO
Bell's theorem has been proposed to certify, in a device-independent and robust way, blocks either producing or measuring quantum states. In this Letter, we provide a method based on Bell's theorem to certify coherent operations for the storage, processing, and transfer of quantum information. This completes the set of tools needed to certify all building blocks of a quantum computer. Our method distinguishes itself by its robustness to experimental imperfections, and so could be used to certify that today's quantum devices are qualified for usage in future quantum computers.
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A recent experiment reported the first violation of a Bell correlation witness in a many-body system [Science 352, 441 (2016)]. Following discussions in this Letter, we address here the question of the statistics required to witness Bell correlated states, i.e., states violating a Bell inequality, in such experiments. We start by deriving multipartite Bell inequalities involving an arbitrary number of measurement settings, two outcomes per party and one- and two-body correlators only. Based on these inequalities, we then build up improved witnesses able to detect Bell correlated states in many-body systems using two collective measurements only. These witnesses can potentially detect Bell correlations in states with an arbitrarily low amount of spin squeezing. We then establish an upper bound on the statistics needed to convincingly conclude that a measured state is Bell correlated.
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BACKGROUND: Pharmacogenomic clinical decision support systems (CDSS) have the potential to help overcome some of the barriers for translating pharmacogenomic knowledge into clinical routine. Before developing a prototype it is crucial for developers to know which pharmacogenomic CDSS features and user-system interactions have yet been developed, implemented and tested in previous pharmacogenomic CDSS efforts and if they have been successfully applied. We address this issue by providing an overview of the designs of user-system interactions of recently developed pharmacogenomic CDSS. METHODS: We searched PubMed for pharmacogenomic CDSS published between January 1, 2012 and November 15, 2016. Thirty-two out of 118 identified articles were summarized and included in the final analysis. We then compared the designs of user-system interactions of the 20 pharmacogenomic CDSS we had identified. RESULTS: Alerts are the most widespread tools for physician-system interactions, but need to be implemented carefully to prevent alert fatigue and avoid liabilities. Pharmacogenomic test results and override reasons stored in the local EHR might help communicate pharmacogenomic information to other internal care providers. Integrating patients into user-system interactions through patient letters and online portals might be crucial for transferring pharmacogenomic data to external health care providers. Inbox messages inform physicians about new pharmacogenomic test results and enable them to request pharmacogenomic consultations. Search engines enable physicians to compare medical treatment options based on a patient's genotype. CONCLUSIONS: Within the last 5 years, several pharmacogenomic CDSS have been developed. However, most of the included articles are solely describing prototypes of pharmacogenomic CDSS rather than evaluating them. To support the development of prototypes further evaluation efforts will be necessary. In the future, pharmacogenomic CDSS will likely include prediction models to identify patients who are suitable for preemptive genotyping.
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Sistemas Computacionais/normas , Sistemas de Apoio a Decisões Clínicas/normas , Testes Farmacogenômicos/normas , Medicina de Precisão/normas , HumanosRESUMO
The slowing down or stalling of replication forks is commonly known as replication stress and arises from multiple causes such as DNA lesions, nucleotide depletion, RNA-DNA hybrids, and oncogene activation. The ataxia telangiectasia and Rad3-related kinase (ATR) plays an essential role in the cellular response to replication stress and inhibition of ATR has emerged as therapeutic strategy for the treatment of cancers that exhibit high levels of replication stress. However, the cellular signaling induced by replication stress and the substrate spectrum of ATR has not been systematically investigated. In this study, we employed quantitative MS-based proteomics to define the cellular signaling after nucleotide depletion-induced replication stress and replication fork collapse following ATR inhibition. We demonstrate that replication stress results in increased phosphorylation of a subset of proteins, many of which are involved in RNA splicing and transcription and have previously not been associated with the cellular replication stress response. Furthermore, our data reveal the ATR-dependent phosphorylation following replication stress and discover novel putative ATR target sites on MCM6, TOPBP1, RAD51AP1, and PSMD4. We establish that ATR inhibition rewires cellular signaling networks induced by replication stress and leads to the activation of the ATM-driven double-strand break repair signaling.
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Antineoplásicos/farmacologia , Replicação do DNA/efeitos dos fármacos , Redes Reguladoras de Genes , Hidroxiureia/farmacologia , Transdução de Sinais/efeitos dos fármacos , Sequência de Aminoácidos , Proteínas Mutadas de Ataxia Telangiectasia/antagonistas & inibidores , Proteínas Mutadas de Ataxia Telangiectasia/genética , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Ciclo Celular/efeitos dos fármacos , Ciclo Celular/genética , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , DNA/genética , DNA/metabolismo , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Humanos , Componente 6 do Complexo de Manutenção de Minicromossomo/genética , Componente 6 do Complexo de Manutenção de Minicromossomo/metabolismo , Dados de Sequência Molecular , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Osteoblastos/efeitos dos fármacos , Osteoblastos/metabolismo , Osteoblastos/patologia , Fosfoproteínas/genética , Fosfoproteínas/metabolismo , Fosforilação , Complexo de Endopeptidases do Proteassoma/genética , Complexo de Endopeptidases do Proteassoma/metabolismo , Mapeamento de Interação de Proteínas , Splicing de RNA , Proteínas de Ligação a RNA , Estresse Fisiológico , Transcrição GênicaRESUMO
B-cell receptor (BCR) signaling is essential for the development and function of B cells; however, the spectrum of proteins involved in BCR signaling is not fully known. Here we used quantitative mass spectrometry-based proteomics to monitor the dynamics of BCR signaling complexes (signalosomes) and to investigate the dynamics of downstream phosphorylation and ubiquitylation signaling. We identify most of the previously known components of BCR signaling, as well as many proteins that have not yet been implicated in this system. BCR activation leads to rapid tyrosine phosphorylation and ubiquitylation of the receptor-proximal signaling components, many of which are co-regulated by both the modifications. We illustrate the power of multilayered proteomic analyses for discovering novel BCR signaling components by demonstrating that BCR-induced phosphorylation of RAB7A at S72 prevents its association with effector proteins and with endo-lysosomal compartments. In addition, we show that BCL10 is modified by LUBAC-mediated linear ubiquitylation, and demonstrate an important function of LUBAC in BCR-induced NF-κB signaling. Our results offer a global and integrated view of BCR signaling, and the provided datasets can serve as a valuable resource for further understanding BCR signaling networks.
Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas de Membrana/genética , Receptores de Antígenos de Linfócitos B/genética , Ubiquitina-Proteína Ligases/genética , Proteínas Adaptadoras de Transdução de Sinal/biossíntese , Proteína 10 de Linfoma CCL de Células B , Linfócitos B/metabolismo , Células HEK293 , Células HeLa , Humanos , Proteínas de Membrana/biossíntese , NF-kappa B/biossíntese , NF-kappa B/genética , Fosforilação/genética , Proteômica , Receptores de Antígenos de Linfócitos B/biossíntese , Transdução de Sinais/genética , Ubiquitina-Proteína Ligases/biossíntese , Ubiquitinação/genéticaRESUMO
We report the Prandtl-number (Pr) and Rayleigh-number (Ra) dependencies of the Reynolds number (Re) and mean convective heat transport, measured by the Nusselt number (Nu), in horizontal convection (HC) systems, where the heat supply and removal are provided exclusively through a lower horizontal surface of a fluid layer. For laminar HC, we find that Reâ¼Ra^{2/5}Pr^{-4/5}, Nuâ¼Ra^{1/5}Pr^{1/10} with a transition to Reâ¼Ra^{1/2}Pr^{-1}, Nuâ¼Ra^{1/4}Pr^{0} for large Pr. The results are based on direct numerical simulations for Ra from 3×10^{8} to 5×10^{10} and Pr from 0.05 to 50 and are explained by applying the Grossmann-Lohse approach [J. Fluid Mech. 407, 27 (2000)] transferred from the case of Rayleigh-Bénard convection to the case of laminar HC.
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The type II transmembrane serine protease matriptase is a potential target for anticancer therapy and might be involved in cartilage degradation in osteoarthritis or inflammatory skin disorders. Starting from previously described nonspecific thrombin and factor Xa inhibitors we have prepared new noncovalent substrate-analogs with superior potency against matriptase. The most suitable compound 35 (H-d-hTyr-Ala-4-amidinobenzylamide) binds to matriptase with an inhibition constant of 26 nM and has more than 10-fold reduced activity against thrombin and factor Xa. The crystal structure of inhibitor 35 was determined in the surrogate protease trypsin, the obtained complex was used to model the binding mode of inhibitor 35 in the active site of matriptase. The methylene insertion in d-hTyr and d-hPhe increases the flexibility of the P3 side chain compared to their d-Phe analogs, which enables an improved binding of these inhibitors in the well-defined S3/4 pocket of matriptase. Inhibitor 35 can be used for further biochemical studies with matriptase.