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1.
Cell ; 187(12): 2935-2951.e19, 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38772371

RESUMO

Peripheral sensory neurons widely innervate various tissues to continuously monitor and respond to environmental stimuli. Whether peripheral sensory neurons innervate the spleen and modulate splenic immune response remains poorly defined. Here, we demonstrate that nociceptive sensory nerve fibers extensively innervate the spleen along blood vessels and reach B cell zones. The spleen-innervating nociceptors predominantly originate from left T8-T13 dorsal root ganglia (DRGs), promoting the splenic germinal center (GC) response and humoral immunity. Nociceptors can be activated by antigen-induced accumulation of splenic prostaglandin E2 (PGE2) and then release calcitonin gene-related peptide (CGRP), which further promotes the splenic GC response at the early stage. Mechanistically, CGRP directly acts on B cells through its receptor CALCRL-RAMP1 via the cyclic AMP (cAMP) signaling pathway. Activating nociceptors by ingesting capsaicin enhances the splenic GC response and anti-influenza immunity. Collectively, our study establishes a specific DRG-spleen sensory neural connection that promotes humoral immunity, suggesting a promising approach for improving host defense by targeting the nociceptive nervous system.


Assuntos
Peptídeo Relacionado com Gene de Calcitonina , Centro Germinativo , Imunidade Humoral , Baço , Animais , Masculino , Camundongos , Linfócitos B/imunologia , Linfócitos B/metabolismo , Peptídeo Relacionado com Gene de Calcitonina/metabolismo , Capsaicina/farmacologia , AMP Cíclico/metabolismo , Dinoprostona/metabolismo , Gânglios Espinais/metabolismo , Centro Germinativo/imunologia , Camundongos Endogâmicos C57BL , Nociceptores/metabolismo , Proteína 1 Modificadora da Atividade de Receptores/metabolismo , Células Receptoras Sensoriais/metabolismo , Células Receptoras Sensoriais/efeitos dos fármacos , Transdução de Sinais , Baço/inervação , Baço/imunologia , Feminino
2.
Cell ; 178(1): 176-189.e15, 2019 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-31155231

RESUMO

RLR-mediated type I IFN production plays a pivotal role in elevating host immunity for viral clearance and cancer immune surveillance. Here, we report that glycolysis, which is inactivated during RLR activation, serves as a barrier to impede type I IFN production upon RLR activation. RLR-triggered MAVS-RIG-I recognition hijacks hexokinase binding to MAVS, leading to the impairment of hexokinase mitochondria localization and activation. Lactate serves as a key metabolite responsible for glycolysis-mediated RLR signaling inhibition by directly binding to MAVS transmembrane (TM) domain and preventing MAVS aggregation. Notably, lactate restoration reverses increased IFN production caused by lactate deficiency. Using pharmacological and genetic approaches, we show that lactate reduction by lactate dehydrogenase A (LDHA) inactivation heightens type I IFN production to protect mice from viral infection. Our study establishes a critical role of glycolysis-derived lactate in limiting RLR signaling and identifies MAVS as a direct sensor of lactate, which functions to connect energy metabolism and innate immunity.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteína DEAD-box 58/antagonistas & inibidores , Proteína DEAD-box 58/metabolismo , Ácido Láctico/farmacologia , Receptores de Superfície Celular/antagonistas & inibidores , Receptores de Superfície Celular/metabolismo , Animais , Feminino , Glicólise , Células HEK293 , Humanos , Interferon beta/metabolismo , L-Lactato Desidrogenase/genética , L-Lactato Desidrogenase/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Células RAW 264.7 , Receptores Imunológicos , Transdução de Sinais/efeitos dos fármacos , Transfecção
3.
Mol Cell ; 82(21): 4018-4032.e9, 2022 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-36332605

RESUMO

Kinetochore assembly on centromeres is central for chromosome segregation, and defects in this process cause mitotic errors and aneuploidy. Besides the well-established protein network, emerging evidence suggests the involvement of regulatory RNA in kinetochore assembly; however, it has remained elusive about the identity of such RNA, let alone its mechanism of action in this critical process. Here, we report CCTT, a previously uncharacterized long non-coding RNA (lncRNA) transcribed from the arm of human chromosome 17, which plays a vital role in kinetochore assembly. We show that CCTT highly localizes to all centromeres via the formation of RNA-DNA triplex and specifically interacts with CENP-C to help engage this blueprint protein in centromeres, and consequently, CCTT loss triggers extensive mitotic errors and aneuploidy. These findings uncover a non-centromere-derived lncRNA that recruits CENP-C to centromeres and shed critical lights on the function of centromeric DNA sequences as anchor points for kinetochore assembly.


Assuntos
RNA Longo não Codificante , Humanos , Aneuploidia , Proteína Centromérica A/metabolismo , DNA , Cinetocoros/metabolismo , RNA Longo não Codificante/genética , Centrômero
4.
Mol Cell ; 68(1): 185-197.e6, 2017 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-28943315

RESUMO

Many infections and stress signals can rapidly activate the NLRP3 inflammasome to elicit robust inflammatory responses. This activation requires a priming step, which is thought to be mainly for upregulating NLRP3 transcription. However, recent studies report that the NLRP3 inflammasome can be activated independently of transcription, suggesting that the priming process has unknown essential regulatory steps. Here, we report that JNK1-mediated NLRP3 phosphorylation at S194 is a critical priming event and is essential for NLRP3 inflammasome activation. We show that NLRP3 inflammasome activation is disrupted in NLRP3-S194A knockin mice. JNK1-mediated NLRP3 S194 phosphorylation is critical for NLRP3 deubiquitination and facilitates its self-association and the subsequent inflammasome assembly. Importantly, we demonstrate that blocking S194 phosphorylation prevents NLRP3 inflammasome activation in cryopyrin-associated periodic syndromes (CAPS). Thus, our study reveals a key priming molecular event that is a prerequisite for NLRP3 inflammasome activation. Inhibiting NLRP3 phosphorylation could be an effective treatment for NLRP3-related diseases.


Assuntos
Inflamassomos/genética , Macrófagos/imunologia , Proteína Quinase 8 Ativada por Mitógeno/genética , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Choque Séptico/genética , Sequência de Aminoácidos , Animais , Enzimas Desubiquitinantes/genética , Enzimas Desubiquitinantes/imunologia , Escherichia coli/química , Feminino , Regulação da Expressão Gênica , Células HEK293 , Humanos , Inflamassomos/imunologia , Lipopolissacarídeos/farmacologia , Macrófagos/patologia , Masculino , Camundongos , Camundongos Transgênicos , Proteína Quinase 8 Ativada por Mitógeno/imunologia , Proteína 3 que Contém Domínio de Pirina da Família NLR/deficiência , Proteína 3 que Contém Domínio de Pirina da Família NLR/imunologia , Fosforilação , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Choque Séptico/induzido quimicamente , Choque Séptico/mortalidade , Choque Séptico/patologia , Transdução de Sinais , Análise de Sobrevida
5.
Nucleic Acids Res ; 51(3): 1050-1066, 2023 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-36660824

RESUMO

While linear ubiquitin plays critical roles in multiple cell signaling pathways, few substrates have been identified. Global profiling of linear ubiquitin substrates represents a significant challenge because of the low endogenous level of linear ubiquitination and the background interference arising from highly abundant ubiquitin linkages (e.g. K48- and K63-) and from the non-specific attachment of interfering proteins to the linear polyubiquitin chain. We developed a bio-orthogonal linear ubiquitin probe by site-specific encoding of a norbornene amino acid on ubiquitin (NAEK-Ub). This probe facilitates covalent labeling of linear ubiquitin substrates in live cells and enables selective enrichment and identification of linear ubiquitin-modified proteins. Given the fact that the frequent overexpression of the linear linkage-specific deubiquitinase OTULIN correlates with poor prognosis in glioblastoma, we demonstrated the feasibility of the NAEK-Ub strategy by identifying and validating substrates of linear ubiquitination in patient-derived glioblastoma stem-like cells (GSCs). We identified STAT3 as a bona fide substrate of linear ubiquitin, and showed that linear ubiquitination negatively regulates STAT3 activity by recruitment of the phosphatase TC-PTP to STAT3. Furthermore, we demonstrated that preferential expression of OTULIN in GSCs restricts linear ubiquitination on STAT3 and drives persistent STAT3 signaling, and thereby maintains the stemness and self-renewal of GSCs.


Assuntos
Glioblastoma , Fator de Transcrição STAT3 , Ubiquitina , Humanos , Poliubiquitina/genética , Transdução de Sinais , Fator de Transcrição STAT3/metabolismo , Ubiquitina/metabolismo , Ubiquitinação
6.
Angew Chem Int Ed Engl ; 63(29): e202405913, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38683647

RESUMO

Inactivating hyperactivated transcription factors can overcome tumor therapy resistance, but their undruggable features limit the development of conventional inhibitors. Here, we report that carbon-centered free radicals (R⋅) can inactivate NF-κB transcription by capping the active sites in both NF-κB and DNA. We construct a type of thermosensitive R⋅ initiator loaded amphiphilic nano-micelles to facilitate intracellular delivery of R⋅. At a temperature of 43 °C, the generated R⋅ engage in electrophilic radical addition towards double bonds in nucleotide bases, and simultaneously cap the sulfhydryl residues in NF-κB through radical chain reaction. As a result, both NF-κB nuclear translocation and NF-κB-DNA binding are suppressed, leading to a remarkable NF-κB inhibition of up to 94.1 %. We have further applied R⋅ micelles in a clinical radiofrequency ablation tumor therapy model, showing remarkable NF-κB inactivation and consequently tumor metastasis inhibition. Radical capping strategy not only provides a method to solve the heat-sink effect in clinic tumor hyperthermia, but also suggests a new perspective for controllable modification of biomacromolecules in cancer therapy.


Assuntos
Carbono , NF-kappa B , NF-kappa B/metabolismo , NF-kappa B/antagonistas & inibidores , Radicais Livres/química , Radicais Livres/metabolismo , Humanos , Carbono/química , Micelas , DNA/química , DNA/metabolismo , Animais , Camundongos
7.
Anal Chem ; 95(23): 9068-9075, 2023 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-37267452

RESUMO

Microarrays have been widely used for multiplexed bioassays. Fabrication of a conventional microarray typically requires a complex microarray spotter, using which nanoliter bioreagent (e.g., antibody and cells) droplets are delivered onto a glass slide. However, arraying a delicate bioreagent in nanoliter volumes could cause the loss of bioactivity and needs a complex microarray spotter. Further, mixing of different bioreagents in a multiplexed assay leads to cross-reactions, producing false positive signals that impair assay reproducibility and scalability. In this work, we propose a new microarray format, named "compartmentalized linker array (CLA)", that consists of pre-prepared storable microarrays of chemical linkers in microliter compartments. CLA can be used for binding and patterning bioreagents into microarrays by simply pipetting and incubating bioreagent solutions in compartments. Using commonly used aminosilane linker-based antibody microarray, we developed CLA and demonstrated its application for a multiplexed sandwich immunoassay measuring three cancer-related proteins. A "two-phase" blocking system was established for de-activating background regions on glass where no linker molecules are present. Storage conditions of the CLA chip were explored and demonstrated for long-term storage. In a multiplexed immunoassay, low pg/mL sensitivity was achieved for all the three proteins, comparable to those of conventional assays. Moreover, CLA can be potentially used for other applications beyond protein assays, making microarray technology transferrable and widely available for the biological and biomedical research community.


Assuntos
Análise Serial de Proteínas , Proteínas , Reprodutibilidade dos Testes , Análise em Microsséries , Imunoensaio , Anticorpos/química
8.
Anal Biochem ; 683: 115369, 2023 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-37914004

RESUMO

Microarrays are powerful tools for high-throughput bioassays that can extract information from tens of thousands of micro-spots consisting of biomolecules. This information is invaluable to many applications, such as drug discovery and disease diagnostics. Different applications of these microarrays need spots of different shapes, sizes, and chemistries to achieve their goals. Micro/nano-fabrication techniques are used to make microarrays with different feature structures and array densities for required assay procedures. Understanding these fabrication methods is essential to creating an effective microarray. The purpose of this article is to critically review fabrication methods used in recent microarray-based bioassay studies. We summarized commonly used microarray fabrication techniques and filled the gap in recent literature on relevant topics. We discussed recent examples of how microarrays were fabricated and used in a variety of bioassays. Specifically, we examined microarray printing, various microlithography techniques, and microfluidics-based microarray fabrication. We evaluated how their application shaped the fabrication methods and compared their performance based on different applications. In the end, we discussed current challenges and outlined potential future directions. This review addressed the gap in literature and provided important insights for choosing appropriate fabrication techniques towards different applications.


Assuntos
Bioensaio , Microfluídica , Análise em Microsséries
9.
Anal Bioanal Chem ; 415(10): 1967-1977, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36829042

RESUMO

Background noise due to nonspecific binding of biomolecules on the assay substrates is one of the most common challenges that limits the sensitivity of microarray-based immunoassays. Background signal intensity usually increases when complex biological fluids are used because they have a combination of molecules and vesicles that can adsorb onto substrate surfaces. Blocking strategies coupled with surface chemistries can reduce such nonspecific binding and improve assay sensitivity. In this paper, we conducted a systematic optimization of blocking strategies on a variety of commonly used substrates for protein measurement in complex biofluids. Four blocking strategies (BSA, non-fat milk, PEG, and a protein-free solution) coupled with four surface chemistries (3-glycidoxypropyltrimethoxysilane (GPS), poly-L-lysine (PLL), aminoalkylsilane (AAS), and nitrocellulose (NC)) were studied for their effect on background, microspot, and net signal intensities. We have also explored the effect that these blocking strategies have when proteins in complex samples (plasma, serum, cell culture media, and EV lysate) are measured. Irregular spot morphology could affect signal extraction using automated software. We found that the microspots with the best morphology were the ones printed on GPS glass surfaces for all immunoassays. On NC membrane, the protein-based blocking strategies yielded the highest net fluorescent intensity with the antigen contained in PBS, plasma, serum, and serum-free cell culture media. Differently, with EV lysate samples, Pierce™ protein-free blocker yielded the best net signal intensity on both GPS and NC surfaces. The choice of blocking strategies highly depends on the substrate. Moreover, the findings discovered in this study are not limited to microarray-based immunoassays but can provide insights for other assay formats.


Assuntos
Anticorpos , Proteínas , Indicadores e Reagentes , Análise em Microsséries , Proteínas/química , Imunoensaio , Propriedades de Superfície
10.
Mikrochim Acta ; 190(4): 144, 2023 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-36939899

RESUMO

Conventional cellular protein detection techniques such as immunocytochemistry and flow cytometry require abundant cells, posing multiple challenges, including difficulty and cost for obtaining enough cells and the potential for clogging the instrument when using flow cytometry. Also, it is challenging to conduct cellular protein imaging and quantification simultaneously from a single experiment. We present a novel 3D platform, which integrates highly biocompatible cell-entrapped alginate hydrogel droplet array with gold-nanoparticle (AuNP)-based metal enhanced fluorescence (MEF), to achieve simultaneous imaging and quantification of proteins in intact cells in a sensitive manner. Compared to 2D immunocytochemistry, this 3D system allows for a higher cell loading capacity per unit area; together with the MEF-based signal enhancement from the embedded AuNPs, sensitive protein quantification was realized. Furthermore, compared to flow cytometry, this platform allows for protein imaging from individual cells. Taking the detection of EpCAM protein in ovarian cancer cells as a model, we optimized the AuNP size and concentration for optimal fluorescent signals. The 5 nm AuNPs at 6.54 × 1013 particles/mL proved to be the most effective in signal enhancement, providing 2.4-fold higher signals compared to that without AuNPs and 6.4-fold higher signals than that of 2D immunocytochemistry. The number of cells required in our technology is 1-3 orders of magnitude smaller than that of conventional methods. This AuNP-embedded hydrogel platform combines the benefits of immunocytochemistry and flow cytometry, providing increased assay sensitivity while also allowing for qualitative analysis through imaging, suitable for protein determination in a variety of cells.


Assuntos
Hidrogéis , Nanopartículas Metálicas , Ouro , Fluorescência
11.
Adv Skin Wound Care ; 36(4): 206-212, 2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-36940377

RESUMO

OBJECTIVE: To explore the application potential of continuous nursing training based on a comprehensive virtual platform in patients with colostomy or ileostomy. METHODS: A total of 100 patients with colostomy or ileostomy were equally divided into two groups. Patients in the control group received standardized routine care, whereas patients in the experimental group received continuous nursing care through the virtual platform. Both the control group and the experimental group were followed up by regular telephone calls once per week and completed the following questionnaires both 1 week after discharge and 3 months after discharge: Stoma Care Self-efficacy Scale, Exercise of Self-care Agency Scale, State-Trait Anxiety Inventory, Short Form-36 Health Survey Questionnaire, and a questionnaire on postoperative complications. RESULTS: Patients in the experimental group, who received continuous care, exhibited significantly higher scores in self-efficacy (P = .029), self-care responsibility (P = 0.030), state anxiety and trait anxiety (both Ps < .001), and mental health (P < .001) 1 week after discharge in comparison with patients in the control group. At 3 months postdischarge, compared with the control group, the experimental group showed significant advantages in all dimensions of self-efficacy, self-care ability, mental health, and quality-of-life questionnaires (P < .001). In addition, the incidence of complications in the experimental group was significantly lower (P < .0001). CONCLUSIONS: The virtual platform-based continuous nursing model effectively improves the self-care ability and self-efficacy of patients with a colostomy or ileostomy after colorectal cancer, thereby promoting an improved quality of life and psychological state while simultaneously reducing the incidence of complications after discharge.


Assuntos
Colostomia , Ileostomia , Humanos , Colostomia/métodos , Assistência ao Convalescente , Qualidade de Vida/psicologia , Alta do Paciente
12.
Int Ophthalmol ; 43(5): 1581-1590, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36269442

RESUMO

PURPOSE: To investigate the impact of drooping eyelid on corneal topographic and tomographic alterations in congenital ptosis eyes. METHODS: Seventeen Chinese patients with unilateral congenital ptosis were included in this observational study. Ptosis eyes were included in the ptosis group, while normal contralateral eyes were included in the control group. The marginal reflex distance (MRD) was used to evaluate the severity of ptosis. Topographic and tomographic parameters measured by Pentacam, including keratometric, pachymetric, volumetric parameters as well as topometric indexes and D indexes, were recorded and compared between the ptosis group and the control group. Furthermore, correlation analyses were made between MRD and all measured corneal parameters. RESULTS: The value of anterior K1, Km and posterior K2, Km was significantly decreased in the ptosis eyes (p < 0.05). Corneal thickness at the pupil center point and thinnest point was significantly thicker in ptosis group compared with the ones in control group (p < 0.05). Higher ISV, IVA, KI, IHD values were observed in ptosis eyes (p < 0.05). The intergroup difference in MRD showed significant correlation with the difference in ISV (p < 0.05). CONCLUSION: The whole corneal contour is remodeled to be "flatter" in ptosis eyes. The upper eyelid position was closely associated with the corneal irregularity in ptosis eyes. The reasons for the discrepancy in corneal topography and tomography between ptotic and normal eyes were complicated.


Assuntos
Blefaroptose , Ceratocone , Humanos , Topografia da Córnea/métodos , Córnea/diagnóstico por imagem , Blefaroptose/diagnóstico , Blefaroptose/congênito , Tomografia , China/epidemiologia , Paquimetria Corneana/métodos
13.
Angew Chem Int Ed Engl ; 62(7): e202210415, 2023 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-36650984

RESUMO

Since the insight to fuse Fenton chemistry and nanomedicine into cancer therapy, great signs of progress have been made in the field of chemodynamic therapy (CDT). However, the exact mechanism of CDT is obscured by the unique tumor chemical environment and inevitable nanoparticle-cell interactions, thus impeding further development. In this Scientific Perspective, the significance of CDT is clarified, the complex mechanism is deconstructed into primitive chemical and biological interactions, and the mechanism research directions based on the chemical kinetics and biological signaling pathways are discussed in detail. Moreover, beneficial outlooks are presented to enlighten the evolution of next-generation CDT. Hopefully, this Scientific Perspective can inspire new ideas and advances for CDT and provide a reference for breaking down the interdisciplinary barriers in the field of nanomedicine.


Assuntos
Nanopartículas , Neoplasias , Humanos , Neoplasias/metabolismo , Nanomedicina , Linhagem Celular Tumoral , Peróxido de Hidrogênio/metabolismo , Microambiente Tumoral
14.
Angew Chem Int Ed Engl ; 62(15): e202300356, 2023 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-36780170

RESUMO

Sustained signal activation by hydroxyl radicals (⋅OH) has great significance, especially for tumor treatment, but remains challenging. Here, a built-in electric field (BIEF)-driven strategy was proposed for sustainable generation of ⋅OH, thereby achieving long-lasting chemodynamic therapy (LCDT). As a proof of concept, a novel Janus-like Fe@Fe3 O4 -Cu2 O heterogeneous catalyst was designed and synthesized, in which the BIEF induced the transfer of electrons in the Fe core to the surface, reducing ≡Cu2+ to ≡Cu+ , thus achieving continuous Fenton-like reactions and ⋅OH release for over 18 h, which is approximately 12 times longer than that of Fe3 O4 -Cu2 O and 72 times longer than that of Cu2 O nanoparticles. In vitro and in vivo antitumor results indicated that sustained ⋅OH levels led to persistent extracellular regulated protein kinases (ERK) signal activation and irreparable oxidative damage to tumor cells, which promoted irreversible tumor apoptosis. Importantly, this strategy provides ideas for developing long-acting nanoplatforms for various applications.


Assuntos
Nanopartículas , Neoplasias , Humanos , Neoplasias/tratamento farmacológico , Nanopartículas/química , Radical Hidroxila/metabolismo , Estresse Oxidativo , Peróxido de Hidrogênio/metabolismo , Linhagem Celular Tumoral
15.
Proteomics ; 22(4): e2100230, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34933412

RESUMO

Blood protein markers have been studied for the clinical management of cancer. Due to the large number of the proteins existing in blood, it is often necessary to pre-select potential protein markers before experimental studies. However, to date there is a lack of automated method for in-silico selection of cancer blood proteins that integrates the information from both genetic and proteomic studies in a cancer-specific manner. In this work, we synthesized both genomic and proteomic information from several open access databases and established a bioinformatic pipeline for in-silico selection of blood plasma proteins overexpressed in specific type of cancer. We demonstrated the workflow of this pipeline with an example of breast cancer, while the methodology was applicable for other cancer types. With this pipeline we obtained 10 candidate biomarkers for breast cancer. The proposed pipeline provides a useful and convenient tool for in-silico selection of candidate blood protein biomarkers for a variety of cancer research.


Assuntos
Neoplasias da Mama , Proteômica , Proteínas Sanguíneas/genética , Neoplasias da Mama/genética , Biologia Computacional/métodos , Bases de Dados Genéticas , Feminino , Genômica/métodos , Humanos , Proteômica/métodos
16.
J Biol Chem ; 297(6): 101360, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34756889

RESUMO

Human structure-specific recognition protein 1 (hSSRP1) is an essential component of the facilitates chromatin transcription complex, which participates in nucleosome disassembly and reassembly during gene transcription and DNA replication and repair. Many functions, including nuclear localization, histone chaperone activity, DNA binding, and interaction with cellular proteins, are attributed to hSSRP1, which contains multiple well-defined domains, including four pleckstrin homology (PH) domains and a high-mobility group domain with two flanking disordered regions. However, little is known about the mechanisms by which these domains cooperate to carry out hSSRP1's functions. Here, we report the biochemical characterization and structure of each functional domain of hSSRP1, including the N-terminal PH1, PH2, PH3/4 tandem PH, and DNA-binding high-mobility group domains. Furthermore, two casein kinase II binding sites in hSSRP1 were identified in the PH3/4 domain and in a disordered region (Gly617-Glu709) located in the C-terminus of hSSRP1. In addition, a histone H2A-H2B binding motif and a nuclear localization signal (Lys677‒Asp687) of hSSRP1 are reported for the first time. Taken together, these studies provide novel insights into the structural basis for hSSRP1 functionality.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Proteínas de Grupo de Alta Mobilidade/metabolismo , Fatores de Elongação da Transcrição/metabolismo , Sequência de Aminoácidos , Sítios de Ligação , Proteínas de Ligação a DNA/química , Proteínas de Grupo de Alta Mobilidade/química , Humanos , Sinais de Localização Nuclear , Conformação Proteica , Domínios Proteicos , Homologia de Sequência de Aminoácidos , Fatores de Elongação da Transcrição/química
17.
Anal Chem ; 94(20): 7368-7374, 2022 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-35533397

RESUMO

Extracellular vesicles (EVs) are nanoscale vesicles secreted from cells, carrying biomolecular cargos similar to their cells of origin. Measuring the protein content of EVs in biofluids can offer a crucial insight into human health and disease. For example, detecting tumor-derived EVs' protein markers can aid in early diagnosis of cancer, which is life-saving. In order to use these EV proteins for diagnosis, sensitive and multiplexed methods are required. The current methods for EV protein detection typically require large sample consumption due to challenges with sensitivity and often need an EV isolation step for complex biofluid samples such as blood plasma. In this work, we have developed a simple and sensitive method for multiplexed detection of protein markers on EV membrane surfaces, which we call "EV dot blotting", inspired by conventional dot blotting techniques. After optimization of multiple factors such as antibody concentration, blocking reagent, type of 3D membranes, and use of gold nanoparticles for signal enhancement, cancer-cell-derived EVs were spiked in pooled normal human plasma for conducting a multiplexed assay in a microarray format. Without the need of isolating EVs from blood plasma, a limit of detection of 3.1 × 105 EVs/mL or 1863 EVs/sample was achieved for CD9 protein, 4.7 × 104 EVs/mL or 281 EVs/sample for CD24, and 9.0 × 104 EVs/mL or 538 EVs/sample for EpCAM, up to 4 orders of magnitude lower than those of conventional ELISA. This platform offers sensitive, multiplexed, simple, and low-cost EV protein detection directly from complex biofluids with minimal sample consumption, providing a useful tool for multiplexed EV protein quantification for a variety of applications.


Assuntos
Vesículas Extracelulares , Nanopartículas Metálicas , Biomarcadores Tumorais/metabolismo , Vesículas Extracelulares/metabolismo , Ouro/metabolismo , Humanos , Proteínas/metabolismo
18.
Appl Environ Microbiol ; 88(19): e0126322, 2022 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-36165620

RESUMO

The thermophilic fungus Myceliophthora thermophila has been used to produce industrial enzymes and biobased chemicals. In saprotrophic fungi, the mechanisms regulating cellulase production have been studied, which revealed the involvement of multiple transcription factors. However, in M. thermophila, the transcription factors influencing cellulase gene expression and secretion remain largely unknown. In this study, we identified and characterized a novel cellulase regulator (MtTRC-1) in M. thermophila through a combination of functional genomics and genetic analyses. Deletion of Mttrc-1 resulted in significantly decreased cellulase production and activities. Transcriptome analysis revealed downregulation of not only the encoding genes of main cellulases but also the transcriptional regulator MtHAC-1 of UPR pathway after disruption of MtTRC-1 under cellulolytic induction conditions. Herein, we also characterized the ortholog of the yeast HAC1p in M. thermophila. We show that Mthac-1 mRNA undergoes an endoplasmic reticulum (ER) stress-induced splicing by removing a 23-nucleotide (nt) intron. Notably, the protein secretion on cellulose was dramatically impaired by the deletion of MtHAC-1. Moreover, the colonial growth on various carbon sources was defective in the absence of MtHAC-1. Electrophoretic mobility shift assays and chromatin immunoprecipitation assays verified MtTRC-1 regulates the transcription of Mthac-1 and the major cellulase gene Mtcbh-1 by binding directly to the promoters in vitro and in vivo. Furthermore, DNase I footprinting assays identified the putative consensus binding site (5'-GNG/C-3'). These results revealed the importance of MtTRC-1 for positively regulating cellulase production. This finding has clarified the complex regulatory pathways involved in cellulolytic enzyme production. IMPORTANCE In the present study, we characterized a novel regulator MtTRC-1 in M. thermophila, which regulated cellulase production through direct transcriptional regulation of the Mthac-1 and Mtcbh-1 genes. Our data demonstrated that MtHAC-1 is a key factor for the cellulase secretion capacity of M. thermophila. Our data indicate that this thermophilic fungus regulates cellulase production through a multilevels network, in which the protein secretory pathway is modulated by MtHAC-1-dependent UPR pathway and the cellulase gene expression is directly regulated in parallel by transcription factors. The conservation of Mttrc1 in filamentous fungi suggests this mechanism may be exploited to engineer filamentous fungal cell factories capable of producing proteins on an industrial scale.


Assuntos
Celulase , Celulases , Carbono/metabolismo , Celulase/genética , Celulase/metabolismo , Celulases/metabolismo , Celulose/metabolismo , Desoxirribonuclease I/metabolismo , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Regulação Fúngica da Expressão Gênica , Nucleotídeos , RNA Mensageiro , Sordariales , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
19.
Anal Bioanal Chem ; 414(24): 7051-7067, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35732746

RESUMO

Extracellular vesicles (EVs) are transport vesicles with diameters ranging from 30 to 1000 nm, secreted by cells in both physiological and pathological conditions. By using the EV shuttling system, biomolecular cargo such as proteins and genetic materials travels between cells resulting in intercellular communication and epigenetic regulation. Because the presence of EVs and cargo molecules in body fluids can predict the state of the parental cells, EV isolation techniques from complex biofluids have been developed. Further exploration of EVs through downstream molecular analysis depends heavily on those isolation technologies. Methodologies based either on physical separation or on affinity binding have been used to isolate EVs. Affinity-based methods for EV isolation are known to produce highly specific and efficient isolation results. However, so far, there is a lack of literature summarizing these methods and their effects on downstream EV molecular analysis. In the present work, we reviewed recent efforts on developing affinity-based methods for the isolation of EVs, with an emphasis on comparing their effects on downstream analysis of EV molecular cargo. Antibody-based isolation techniques produce highly pure EVs, but the harsh eluents damage the EV structure, and some antibodies stay bound to the EVs after elution. Aptamer-based methods use relatively mild elution conditions and release EVs in their native form, but their isolation efficiencies need to be improved. The membrane affinity-based method and other affinity-based methods based on the properties of the EV lipid bilayer also isolate intact EVs, but they can also result in contaminants. From the perspective of affinity-based methods, we investigated the influence of the isolation methods of choice on downstream EV molecular analysis.


Assuntos
Vesículas Extracelulares , Bicamadas Lipídicas , Transporte Biológico , Epigênese Genética , Vesículas Extracelulares/química , Proteínas/análise
20.
Future Oncol ; 18(29): 3255-3266, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36000541

RESUMO

HER2-positive gastroesophageal adenocarcinomas (GEAs) are common cancers with high mortality and the treatment options for advanced/metastatic disease are limited. Zanidatamab and tislelizumab are novel monoclonal antibodies targeting HER2 and PD-1, respectively, and have shown encouraging antitumor activity in early phase studies in multiple cancers, including GEA. Preliminary data suggest that dual targeting of the HER2 and PD-1 pathways could further improve upon the results achieved with targeting either pathway alone. Here, we describe the design of HERIZON-GEA-01, a global, randomized, open-label, active-comparator, Phase III study to evaluate and compare the efficacy and safety of zanidatamab plus chemotherapy with or without tislelizumab to the standard of care (trastuzumab plus chemotherapy) as first-line treatment for patients with advanced/metastatic HER2-positive GEAs.


HERIZON-GEA-01: A phase III study of zanidatamab + chemotherapy ± tislelizumab for first-line treatment of advanced or metastatic #HER2-positive gastroesophageal adenocarcinoma (GEA). Clinicaltrials.gov: NCT05152147. #gastriccancer #stomachcancer @ZymeworksInc @BeiGeneGlobal Clinical Trial Registration: NCT05152147 (ClinicalTrials.gov).


Assuntos
Adenocarcinoma , Antineoplásicos , Neoplasias Esofágicas , Neoplasias Gástricas , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/genética , Adenocarcinoma/metabolismo , Anticorpos Monoclonais/uso terapêutico , Anticorpos Monoclonais Humanizados , Antineoplásicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Neoplasias Esofágicas/tratamento farmacológico , Neoplasias Esofágicas/genética , Junção Esofagogástrica/patologia , Humanos , Receptor de Morte Celular Programada 1 , Receptor ErbB-2/metabolismo , Neoplasias Gástricas/patologia , Trastuzumab/farmacologia , Trastuzumab/uso terapêutico
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