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1.
Cell ; 171(4): 904-917.e19, 2017 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-29033133

RESUMO

Nuclear pore complexes (NPCs) are ∼100 MDa transport channels assembled from multiple copies of ∼30 nucleoporins (Nups). One-third of these Nups contain phenylalanine-glycine (FG)-rich repeats, forming a diffusion barrier, which is selectively permeable for nuclear transport receptors that interact with these repeats. Here, we identify an additional function of FG repeats in the structure and biogenesis of the yeast NPC. We demonstrate that GLFG-containing FG repeats directly bind to multiple scaffold Nups in vitro and act as NPC-targeting determinants in vivo. Furthermore, we show that the GLFG repeats of Nup116 function in a redundant manner with Nup188, a nonessential scaffold Nup, to stabilize critical interactions within the NPC scaffold needed for late steps of NPC assembly. Our results reveal a previously unanticipated structural role for natively unfolded GLFG repeats as Velcro to link NPC subcomplexes and thus add a new layer of connections to current models of the NPC architecture.


Assuntos
Poro Nuclear/química , Saccharomyces cerevisiae/citologia , Poro Nuclear/metabolismo , Complexo de Proteínas Formadoras de Poros Nucleares/metabolismo , Biogênese de Organelas , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo
2.
Mol Cell ; 83(18): 3283-3302.e5, 2023 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-37738963

RESUMO

Nuclear pore complexes (NPCs) direct the nucleocytoplasmic transport of macromolecules. Here, we provide a composite multiscale structure of the yeast NPC, based on improved 3D density maps from cryogenic electron microscopy and AlphaFold2 models. Key features of the inner and outer rings were integrated into a comprehensive model. We resolved flexible connectors that tie together the core scaffold, along with equatorial transmembrane complexes and a lumenal ring that anchor this channel within the pore membrane. The organization of the nuclear double outer ring reveals an architecture that may be shared with ancestral NPCs. Additional connections between the core scaffold and the central transporter suggest that under certain conditions, a degree of local organization is present at the periphery of the transport machinery. These connectors may couple conformational changes in the scaffold to the central transporter to modulate transport. Collectively, this analysis provides insights into assembly, transport, and NPC evolution.


Assuntos
Poro Nuclear , Saccharomyces cerevisiae , Saccharomyces cerevisiae/genética , Proteínas de Membrana Transportadoras
3.
EMBO J ; 43(11): 2198-2232, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38649536

RESUMO

Nuclear pore complex (NPC) biogenesis is a still enigmatic example of protein self-assembly. We now introduce several cross-reacting anti-Nup nanobodies for imaging intact nuclear pore complexes from frog to human. We also report a simplified assay that directly tracks postmitotic NPC assembly with added fluorophore-labeled anti-Nup nanobodies. During interphase, NPCs are inserted into a pre-existing nuclear envelope. Monitoring this process is challenging because newly assembled NPCs are indistinguishable from pre-existing ones. We overcame this problem by inserting Xenopus-derived NPCs into human nuclear envelopes and using frog-specific anti-Nup nanobodies for detection. We further asked whether anti-Nup nanobodies could serve as NPC assembly inhibitors. Using a selection strategy against conserved epitopes, we obtained anti-Nup93, Nup98, and Nup155 nanobodies that block Nup-Nup interfaces and arrest NPC assembly. We solved structures of nanobody-target complexes and identified roles for the Nup93 α-solenoid domain in recruiting Nup358 and the Nup214·88·62 complex, as well as for Nup155 and the Nup98 autoproteolytic domain in NPC scaffold assembly. The latter suggests a checkpoint linking pore formation to the assembly of the Nup98-dominated permeability barrier.


Assuntos
Complexo de Proteínas Formadoras de Poros Nucleares , Poro Nuclear , Anticorpos de Domínio Único , Complexo de Proteínas Formadoras de Poros Nucleares/metabolismo , Poro Nuclear/metabolismo , Humanos , Anticorpos de Domínio Único/metabolismo , Animais , Xenopus , Xenopus laevis , Células HeLa
4.
Proc Natl Acad Sci U S A ; 120(25): e2221804120, 2023 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-37307457

RESUMO

The intrinsically disordered FG-Nups in the central channel of the nuclear pore complex (NPC) form a selective permeability barrier, allowing small molecules to traverse by passive diffusion, while large molecules can only translocate with the help of nuclear transport receptors. The exact phase state of the permeability barrier remains elusive. In vitro experiments have shown that some FG-Nups can undergo phase separation into condensates that display NPC-like permeability barrier properties. Here, we use molecular dynamics simulations at amino acid resolution to study the phase separation characteristics of each of the disordered FG-Nups of the yeast NPC. We find that GLFG-Nups undergo phase separation and reveal that the FG motifs act as highly dynamic hydrophobic stickers that are essential for the formation of FG-Nup condensates featuring droplet-spanning percolated networks. Additionally, we study phase separation in an FG-Nup mixture that resembles the NPC stoichiometry and observe that an NPC condensate is formed containing multiple GLFG-Nups. We find that the phase separation of this NPC condensate is also driven by FG-FG interactions, similar to the homotypic FG-Nup condensates. Based on the observed phase separation behavior, the different FG-Nups of the yeast NPC can be divided into two classes: The FG-Nups (mostly GLFG-type) located in the central channel of the NPC form a highly dynamic percolated network formed by many short-lived FG-FG interactions, while the peripheral FG-Nups (mostly FxFG-type) at the entry and exit of the NPC channel likely form an entropic brush.


Assuntos
Aminoácidos , Saccharomyces cerevisiae , Difusão , Entropia , Simulação de Dinâmica Molecular
5.
Genes Cells ; 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38987995

RESUMO

Heat stress strongly triggers the nuclear localization of the molecular chaperone HSP70. Hikeshi functions as a unique nuclear import carrier of HSP70. However, how the nuclear import of HSP70 is activated in response to heat stress remains unclear. Here, we investigated the effects of heat on the nuclear import of HSP70. In vitro transport assays revealed that pretreatment of the test samples with heat facilitated the nuclear import of HSP70. Furthermore, binding of Hikeshi to HSP70 increased when temperatures rose. These results indicated that heat is one of the factors that activates the nuclear import of HSP70. Previous studies showed that the F97A mutation in Hikeshi in an extended loop induced an opening in the hydrophobic pocket and facilitated the translocation of Hikeshi through the nuclear pore complex. We found that nuclear accumulation of HSP70 occurred at a lower temperature in cells expressing the Hikeshi-F97A mutant than in cells expressing wild-type Hikeshi. Collectively, our results show that the movement of the extended loop may play an important role in the interaction of Hikeshi with both FG (phenylalanine-glycine)-nucleoporins and HSP70 in a temperature-dependent manner, resulting in the activation of nuclear import of HSP70 in response to heat stress.

6.
Brief Bioinform ; 24(6)2023 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-37930026

RESUMO

Artificial intelligence-based molecular property prediction plays a key role in molecular design such as bioactive molecules and functional materials. In this study, we propose a self-supervised pretraining deep learning (DL) framework, called functional group bidirectional encoder representations from transformers (FG-BERT), pertained based on ~1.45 million unlabeled drug-like molecules, to learn meaningful representation of molecules from function groups. The pretrained FG-BERT framework can be fine-tuned to predict molecular properties. Compared to state-of-the-art (SOTA) machine learning and DL methods, we demonstrate the high performance of FG-BERT in evaluating molecular properties in tasks involving physical chemistry, biophysics and physiology across 44 benchmark datasets. In addition, FG-BERT utilizes attention mechanisms to focus on FG features that are critical to the target properties, thereby providing excellent interpretability for downstream training tasks. Collectively, FG-BERT does not require any artificially crafted features as input and has excellent interpretability, providing an out-of-the-box framework for developing SOTA models for a variety of molecule (especially for drug) discovery tasks.


Assuntos
Algoritmos , Inteligência Artificial , Benchmarking , Aprendizado de Máquina
7.
Immunology ; 172(4): 614-626, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38685744

RESUMO

Ionising radiation exposure can lead to acute haematopoietic radiation syndrome. Despite significant advancements in the field of radioprotection, no drugs with high efficacy and low toxicity have yet been approved by the Food and Drug Administration. FG-4592, as a proline hydroxylase inhibitor, may play an important role in radioprotection of the haematopoietic system. Mice were peritoneal injected with FG-4592 or normal saline. After irradiation, the survival time, body weight, peripheral blood cell and bone marrow cell (BMC) count, cell apoptosis, pathology were analysed and RNA-sequence technique (RNA-Seq) was conducted to explore the mechanism of FG-4592 in the haematopoietic system. Our results indicated that FG-4592 improved the survival rate and weight of irradiated mice and protected the spleen, thymus and bone marrow from IR-induced injury. The number of BMCs was increased and protected against IR-induced apoptosis. FG-4592 also promoted the recovery of the blood system and erythroid differentiation. The results of RNA-Seq and Western blot showed that the NF-κB signalling pathway and hypoxia-inducible factor-1 (HIF-1) signalling pathway were upregulated by FG-4592. Meanwhile, RT-PCR results showed that FG-4592 could promote inflammatory response significantly. FG-4592 exhibited radioprotective effects in the haematopoietic system by promoting inflammatory response and targeting the NF-κB, HIF signalling pathway.


Assuntos
Apoptose , Radiação Ionizante , Protetores contra Radiação , Animais , Camundongos , Protetores contra Radiação/farmacologia , Apoptose/efeitos dos fármacos , Apoptose/efeitos da radiação , Transdução de Sinais/efeitos dos fármacos , NF-kappa B/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Sistema Hematopoético/efeitos dos fármacos , Sistema Hematopoético/efeitos da radiação , Síndrome Aguda da Radiação/prevenção & controle , Síndrome Aguda da Radiação/tratamento farmacológico , Hematopoese/efeitos dos fármacos , Hematopoese/efeitos da radiação , Lesões Experimentais por Radiação/prevenção & controle , Lesões Experimentais por Radiação/metabolismo , Irradiação Corporal Total , Glicina/análogos & derivados , Isoquinolinas
8.
Cancer Immunol Immunother ; 73(3): 60, 2024 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-38400933

RESUMO

Over the past decade, US Food and Drug Administration (FDA)-approved immune checkpoint inhibitors that target programmed death-1 (PD-1) have demonstrated significant clinical benefit particularly in patients with PD-L1 expressing tumors. Toripalimab is a humanized anti-PD-1 antibody, approved by FDA for first-line treatment of nasopharyngeal carcinoma in combination with chemotherapy. In a post hoc analysis of phase 3 studies, toripalimab in combination with chemotherapy improved overall survival irrespective of PD-L1 status in nasopharyngeal carcinoma (JUPITER-02), advanced non-small cell lung cancer (CHOICE-01) and advanced esophageal squamous cell carcinoma (JUPITER-06). On further characterization, we determined that toripalimab is molecularly and functionally differentiated from pembrolizumab, an anti-PD-1 mAb approved previously for treating a wide spectrum of tumors. Toripalimab, which binds the FG loop of PD-1, has 12-fold higher binding affinity to PD-1 than pembrolizumab and promotes significantly more Th1- and myeloid-derived inflammatory cytokine responses in healthy human PBMCs in vitro. In an ex vivo system employing dissociated tumor cells from treatment naïve non-small cell lung cancer patients, toripalimab induced several unique genes in IFN-γ and immune cell pathways, showed different kinetics of activation and significantly enhanced IFN-γ signature. Additionally, binding of toripalimab to PD-1 induced lower levels of SHP1 and SHP2 recruitment, the negative regulators of T cell activation, in Jurkat T cells ectopically expressing PD-1. Taken together, these data demonstrate that toripalimab is a potent anti-PD-1 antibody with high affinity PD-1 binding, strong functional attributes and demonstrated clinical activity that encourage its continued clinical investigation in several types of cancer.


Assuntos
Anticorpos Monoclonais Humanizados , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Neoplasias Pulmonares , Neoplasias Nasofaríngeas , Humanos , Anticorpos Monoclonais/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/patologia , Antígeno B7-H1 , Receptor de Morte Celular Programada 1 , Neoplasias Pulmonares/tratamento farmacológico , Carcinoma Nasofaríngeo , Neoplasias Esofágicas/tratamento farmacológico , Carcinoma de Células Escamosas do Esôfago/tratamento farmacológico , Linfócitos T/patologia
9.
J Transl Med ; 22(1): 248, 2024 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-38454480

RESUMO

BACKGROUND: Acute ischemic stroke is a common neurological disease with a significant financial burden but lacks effective drugs. Hypoxia-inducible factor (HIF) and prolyl hydroxylases (PHDs) participate in the pathophysiological process of ischemia. However, whether FG4592, the first clinically approved PHDs inhibitor, can alleviate ischemic brain injury remains unclear. METHODS: The infarct volumes and behaviour tests were first analyzed in mice after ischemic stroke with systemic administration of FG4592. The knockdown of HIF-1α and pretreatments of HIF-1/2α inhibitors were then used to verify whether the neuroprotection of FG4592 is HIF-dependent. The targets predicting and molecular docking methods were applied to find other targets of FG4592. Molecular, cell biological and gene knockdown methods were finally conducted to explore the potential neuroprotective mechanisms of FG4592. RESULTS: We found that the systemic administration of FG4592 decreased infarct volume and improved neurological defects of mice after transient or permanent ischemia. Meanwhile, FG4592 also activated autophagy and inhibited apoptosis in peri-infarct tissue of mice brains. However, in vitro and in vivo results suggested that the neuroprotection of FG4592 was not classical HIF-dependent. 2-oxoglutarate and iron-dependent oxygenase domain-containing protein 1 (OGFOD1) was found to be a novel target of FG4592 and regulated the Pro-62 hydroxylation in the small ribosomal protein s23 (Rps23) with the help of target predicting and molecular docking methods. Subsequently, the knockdown of OGFOD1 protected the cell against ischemia/reperfusion injury and activated unfolded protein response (UPR) and autophagy. Moreover, FG4592 was also found to activate UPR and autophagic flux in HIF-1α independent manner. Blocking UPR attenuated the neuroprotection, pro-autophagy effect and anti-apoptosis ability of FG4592. CONCLUSION: This study demonstrated that FG4592 could be a candidate drug for treating ischemic stroke. The neuroprotection of FG4592 might be mediated by inhibiting alternative target OGFOD1, which activated the UPR and autophagy and inhibited apoptosis after ischemic injury. The inhibition of OGFOD1 is a novel therapy for ischemic stroke.


Assuntos
Isquemia Encefálica , AVC Isquêmico , Acidente Vascular Cerebral , Camundongos , Animais , Neuroproteção , Simulação de Acoplamento Molecular , Resposta a Proteínas não Dobradas , Isquemia , Autofagia , Infarto , Isquemia Encefálica/complicações , Isquemia Encefálica/tratamento farmacológico , Isquemia Encefálica/metabolismo , Acidente Vascular Cerebral/tratamento farmacológico , Acidente Vascular Cerebral/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo
10.
Cardiovasc Diabetol ; 23(1): 130, 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38637769

RESUMO

BACKGROUND: Fasting glucose (FG) demonstrates dynamic fluctuations over time and is associated with cardiovascular outcomes, yet current research is limited by small sample sizes and relies solely on baseline glycemic levels. Our research aims to investigate the longitudinal association between FG and silent myocardial infarction (SMI) and also delves into the nuanced aspect of dose response in a large pooled dataset of four cohort studies. METHODS: We analyzed data from 24,732 individuals from four prospective cohort studies who were free of myocardial infarction history at baseline. We calculated average FG and intra-individual FG variability (coefficient of variation), while SMI cases were identified using 12-lead ECG exams with the Minnesota codes and medical history. FG was measured for each subject during the study's follow-up period. We applied a Cox regression model with time-dependent variables to assess the association between FG and SMI with adjustment for age, gender, race, Study, smoking, longitudinal BMI, low-density lipoprotein level, blood pressure, and serum creatinine. RESULTS: The average mean age of the study population was 60.5 (sd: 10.3) years with median fasting glucose of 97.3 mg/dL at baseline. During an average of 9 years of follow-up, 357 SMI events were observed (incidence rate, 1.3 per 1000 person-years). The association between FG and SMI was linear and each 25 mg/dL increment in FG was associated with a 15% increase in the risk of SMI. This association remained significant after adjusting for the use of lipid-lowering medication, antihypertensive medication, antidiabetic medication, and insulin treatment (HR 1.08, 95% CI 1.01-1.16). Higher average FG (HR per 25 mg/dL increase: 1.17, 95% CI 1.08-1.26) and variability of FG (HR per 1 sd increase: 1.23, 95% CI 1.12-1.34) over visits were also correlated with increased SMI risk. CONCLUSIONS: Higher longitudinal FG and larger intra-individual variability in FG over time were associated in a dose-response manner with a higher SMI risk. These findings support the significance of routine cardiac screening for subjects with elevated FG, with and without diabetes.


Assuntos
Glicemia , Infarto do Miocárdio , Humanos , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Risco , Estudos de Coortes , Infarto do Miocárdio/diagnóstico , Infarto do Miocárdio/epidemiologia , Infarto do Miocárdio/complicações
11.
BJU Int ; 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38626885

RESUMO

OBJECTIVE: To examine the role of bowel diversion and reconstructive surgeries in managing Fournier's gangrene (FG) to facilitate multidisciplinary collaboration between urologists, colorectal and plastic surgery teams. METHODS: A review of the literature was conducted using the databases Medline, Embase, PubMed in June 2023. The review included studies that evaluated the outcomes of FG following reconstructive surgeries or diverting colostomies. RESULTS: The existing evidence suggests that bowel diversion and colostomy formation could reduce the need for further debridement, shorten the time to wound healing, and facilitate skin graft or flap uptake in patients with FG. Additionally, the psychological impact of a stoma was shown not to be a major concern for patients. However, stoma carries a risk of perioperative complications and therefore may prolong the length of hospital stay. In reviewing the evidence for reconstruction in FG, large and deep defects seem to benefit from skin grafts or flaps. Noticeably, burial of testicles in thigh pockets has grown out of favour due to concerns regarding the thermoregulation of the testicles and the psychological impact on patients. CONCLUSION: The use of bowel diversion and reconstructive surgeries in managing FG is case dependent. Therefore, it is important to have close discussions with colorectal and plastic surgery teams when managing FG.

12.
Bioessays ; 44(12): e2200181, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36253101

RESUMO

The transactivation response-DNA binding protein of 43 kDa (TDP-43) is an aggregation-prone nucleic acid-binding protein linked to the etiology of Amyotrophic Lateral Sclerosis (ALS) and Frontotemporal Lobar Degeneration (FTLD). These conditions feature the accumulation of insoluble TDP-43 aggregates in the neuronal cytoplasm that lead to cell death. The dynamics between cytoplasmic and nuclear TDP-43 are altered in the disease state where TDP-43 mislocalizes to the cytoplasm, disrupting Nuclear Pore Complexes (NPCs), and ultimately forming large fibrils stabilized by the C-terminal prion-like domain. Here, we review three emerging and poorly understood aspects of TDP-43 biology linked to its aggregation. First, how post-translational modifications in the proximity of TDP-43 N-terminal domain (NTD) promote aggregation. Second, how TDP-43 engages FG-nucleoporins in the NPC, disrupting the pore permeability and function. Third, how the importin α/ß heterodimer prevents TDP-43 aggregation, serving both as a nuclear import transporter and a cytoplasmic chaperone.


Assuntos
Esclerose Lateral Amiotrófica , Degeneração Lobar Frontotemporal , Humanos , alfa Carioferinas/metabolismo , Carioferinas , Degeneração Lobar Frontotemporal/genética , Degeneração Lobar Frontotemporal/metabolismo , Proteínas de Ligação a DNA/metabolismo , Esclerose Lateral Amiotrófica/genética , Esclerose Lateral Amiotrófica/metabolismo
13.
Luminescence ; 39(4): e4741, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38605268

RESUMO

In the present study, a first validated and green spectrofluorimetric approach for its assessment and evaluation in different matrices was investigated. After using an excitation wavelength of 345 nm, Roxadustat (ROX) demonstrates a highly native fluorescence at an emission of 410 nm. The influences of experimental factors such as pH, diluting solvents, and different organized media were tested, and the most appropriate solvent choice was ethanol. It was confirmed that there was a linear relationship between the concentration of ROX and the relative fluorescence intensity in the range 60.0-1000.0 ng ml-1, with the limit of detection and limit of quantitation, respectively, being 17.0 and 53.0 ng ml-1. The mean recoveries % [±standard deviation (SD), n = 5] for pharmaceutical preparations were 100.11% ± 2.24%, whereas for plasma samples, they were 100.08 ± 1.08% (±SD, n = 5). The results obtained after the application of four greenness criteria, Analytical Eco-Scale metric, NEMI, GAPI, and AGREE metric, confirmed its eco-friendliness. In addition, the whiteness meter (RGB12) confirmed its level of sustainability. The International Council for Harmonisation (ICH) criteria were used to verify the developed method through the study in both spiked plasma samples and content uniformity evaluation. An appropriate standard for various applications in industry and quality control laboratories was developed.


Assuntos
Hematínicos , Humanos , Limite de Detecção , Espectrometria de Fluorescência/métodos , Eritropoese , Concentração de Íons de Hidrogênio , Solventes/química , Comprimidos/química , Isoquinolinas
14.
Ter Arkh ; 96(3): 309-311, 2024 Apr 16.
Artigo em Russo | MEDLINE | ID: mdl-38713049

RESUMO

The articles on the history of Russian pulmonology presented in the historical, medical and therapeutic literature contain materials for this history, but their authors did not solve the problem of its consistent presentation, highlighting the stages of formation and founders. The authors of this study critically reviewed the literary and archival primary sources, for the first time proposed the identification of three stages in the development of Russian pulmonology and indicated eight of its founders at these stages. The abundance of material did not allow us to present it in one article. This article is devoted to the 1st stage of the history of pulmonology - the formation of the doctrine of lung diseases. The second (development of pulmonology as an independent scientific direction in internal diseases) and the third (organizational design of pulmonology as a new independent clinical scientific and educational discipline and medical specialty, i.e. its institutionalization) stages will be discussed in the next articles.


Assuntos
Pneumopatias , Pneumologia , Humanos , Pneumologia/história , História do Século XX , Pneumopatias/história , Pneumopatias/terapia , Pneumopatias/diagnóstico , Federação Russa , História do Século XIX
15.
J Cell Sci ; 134(7)2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33912945

RESUMO

Macromolecular cargoes are asymmetrically partitioned in the nucleus or cytoplasm by nucleocytoplasmic transport (NCT). At the center of this activity lies the nuclear pore complex (NPC), through which soluble factors circulate to orchestrate NCT. These include cargo-carrying importin and exportin receptors from the ß-karyopherin (Kapß) family and the small GTPase Ran, which switches between guanosine triphosphate (GTP)- and guanosine diphosphate (GDP)-bound forms to regulate cargo delivery and compartmentalization. Ongoing efforts have shed considerable light on how these soluble factors traverse the NPC permeability barrier to sustain NCT. However, this does not explain how importins and exportins are partitioned in the cytoplasm and nucleus, respectively, nor how a steep RanGTP-RanGDP gradient is maintained across the nuclear envelope. In this Review, we peel away the multiple layers of control that regulate NCT and juxtapose unresolved features against known aspects of NPC function. Finally, we discuss how NPCs might function synergistically with Kapßs, cargoes and Ran to establish the asymmetry of NCT.


Assuntos
Carioferinas , Proteína ran de Ligação ao GTP , Transporte Ativo do Núcleo Celular , Núcleo Celular/metabolismo , Guanosina Trifosfato/metabolismo , Carioferinas/genética , Carioferinas/metabolismo , Membrana Nuclear/metabolismo , Poro Nuclear/metabolismo , Proteína ran de Ligação ao GTP/genética , Proteína ran de Ligação ao GTP/metabolismo
16.
Biol Chem ; 404(8-9): 791-805, 2023 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-37210735

RESUMO

Soluble nuclear transport receptors and stationary nucleoporins are at the heart of the nucleocytoplasmic transport machinery. A subset of nucleoporins contains characteristic and repetitive FG (phenylalanine-glycine) motifs, which are the basis for the permeability barrier of the nuclear pore complex (NPC) that controls transport of macromolecules between the nucleus and the cytoplasm. FG-motifs can interact with each other and/or with transport receptors, mediating their translocation across the NPC. The molecular details of homotypic and heterotypic FG-interactions have been analyzed at the structural level. In this review, we focus on the interactions of nucleoporins with nuclear transport receptors. Besides the conventional FG-motifs as interaction spots, a thorough structural analysis led us to identify additional similar motifs at the binding interface between nucleoporins and transport receptors. A detailed analysis of all known human nucleoporins revealed a large number of such phenylalanine-containing motifs that are not buried in the predicted 3D-structure of the respective protein but constitute part of the solvent-accessible surface area. Only nucleoporins that are rich in conventional FG-repeats are also enriched for these motifs. This additional layer of potential low-affinity binding sites on nucleoporins for transport receptors may have a strong impact on the interaction of transport complexes with the nuclear pore and, thus, the efficiency of nucleocytoplasmic transport.


Assuntos
Complexo de Proteínas Formadoras de Poros Nucleares , Fenilalanina , Humanos , Transporte Ativo do Núcleo Celular , Complexo de Proteínas Formadoras de Poros Nucleares/química , Complexo de Proteínas Formadoras de Poros Nucleares/metabolismo , Sítios de Ligação , Fenilalanina/química , Fenilalanina/metabolismo
17.
Int Urogynecol J ; 34(1): 115-124, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-35831453

RESUMO

INTRODUCTION AND HYPOTHESIS: There were few data about the long-term outcomes of bio-compatible patches for pelvic organ prolapse (POP). The efficacy of poly (L-lactide-co-caprolactone) blended with fibrinogen [P(LLA-CL)/Fg] bio-patches were investigated for anterior vaginal wall prolapse treatment in a 6-year follow-up. METHODS: The P(LLA-CL)/Fg bio-patch was fabricated through electrospinning. Nineteen patients with symptomatic anterior prolapse (Pelvic Organ Prolapse Quantification [POP-Q] stage ≥ 2) were treated with anterior pelvic reconstruction surgery using a P(LLA-CL)/Fg bio-patch and were followed up at 1, 2, 3, 6 months, and 6 years. The primary outcome was objective anatomical cure (anterior POP-Q stage ≤ 1). Secondary outcomes included complications, MRI evaluation, and scores of the Pelvic Floor Impact Questionnaire-7 (PFIQ-7) and the Pelvic Floor Distress Inventory-20 (PFDI-20). RESULTS: The micro-morphology of the bio-patch resembled the extracellular matrix, which was suitable for the growth of fibroblasts. Sixteen (84.2%) patients were finally assessed, with a mean follow-up of 6.08 ± 0.18 years. The cure rate without anterior prolapse recurrence was 93.8% at 6 years. Compared with baseline, the POP-Q measurements of Aa, Ba, and C points and scores of PFIQ-7 and PFDI-20 manifested significant differences at all times (all p < 0.05). One (5.26%) case of bio-patch-related infection, 1 (5.26%) case of urinary retention, and no exposures and erosion occurred. MRI evaluation showed that the bio-patch gradually degraded to fragments at 1 month and was completely absorbed at 3 months. CONCLUSIONS: Among long-term follow-ups, anterior pelvic reconstruction surgery with a P(LLA-CL)/Fg bio-patch demonstrated significant improvements in anatomical correction of anterior pelvic prolapse and pelvic function without severe morbidity.


Assuntos
Prolapso de Órgão Pélvico , Prolapso Uterino , Feminino , Humanos , Resultado do Tratamento , Seguimentos , Vagina/cirurgia , Telas Cirúrgicas , Prolapso de Órgão Pélvico/cirurgia , Inquéritos e Questionários , Qualidade de Vida
18.
Int J Mol Sci ; 24(10)2023 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-37239918

RESUMO

Amyloids are fibrillar protein aggregates with a cross-ß structure. More than two hundred different proteins with amyloid or amyloid-like properties are already known. Functional amyloids with conservative amyloidogenic regions were found in different organisms. Protein aggregation appears to be beneficial for the organism in these cases. Therefore, this property might be conservative for orthologous proteins. The amyloid aggregates of the CPEB protein were suggested to play an important role in the long-term memory formation in Aplysia californica, Drosophila melanogaster, and Mus musculus. Moreover, the FXR1 protein demonstrates amyloid properties among the Vertebrates. A few nucleoporins (e.g., yeast Nup49, Nup100, Nup116, and human Nup153 and Nup58), are supposed or proved to form amyloid fibrils. In this study, we performed wide-scale bioinformatic analysis of nucleoporins with FG-repeats (phenylalanine-glycine repeats). We demonstrated that most of the barrier nucleoporins possess potential amyloidogenic properties. Furthermore, the aggregation-prone properties of several Nsp1 and Nup100 orthologs in bacteria and yeast cells were analyzed. Only two new nucleoporins, Drosophila melanogaster Nup98 and Schizosaccharomyces pombe Nup98, aggregated in different experiments. At the same time, Taeniopygia guttata Nup58 only formed amyloids in bacterial cells. These results rather contradict the hypothesis about the functional aggregation of nucleoporins.


Assuntos
Complexo de Proteínas Formadoras de Poros Nucleares , Proteínas de Saccharomyces cerevisiae , Camundongos , Animais , Humanos , Complexo de Proteínas Formadoras de Poros Nucleares/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Amiloide/metabolismo , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Proteínas Amiloidogênicas/metabolismo , Proteínas de Ligação a RNA/metabolismo , Proteínas Nucleares/metabolismo
19.
Int J Mol Sci ; 24(3)2023 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-36768900

RESUMO

α-thalassemia is characterized in about 80% of cases by deletions generated by the presence of duplications and interspersed repeated sequences in the α-globin gene cluster. In a project on the molecular basis of α-thalassemia in Southern Italy, we identified six families, showing an absence of the most common deletions, and normal α-globin gene sequences. Multiplex Ligation-dependent Probe Amplification (MLPA), qRT-PCR, and the sequencing of long-range PCR amplicon have been used for the identification and characterization of new deletions. MLPA analysis for the identification of α- and ß-globin rearrangement revealed the presence of five new α-thalassemia deletions. The set-up of qRT-PCR allowed us to delimit the extent of the deletions ranging from about 10 kb to more than 250 kb, two of them being of the telomeric type. The long-range PCR generated a specific anomalous fragment in three deletions, and only several unspecific bands in the other two deletions. The sequencing of the anomalous amplicons revealed the breakpoints of two deletions: the --PA, 34 kb long, identified in two families, and the telomeric --AG, 274 kb long. The anomalous fragment containing the breakpoint of the deletion --FG was partially sequenced, and it was not possible to identify the breakpoints due to the presence of several repetitive Alu sequences. The analysis of the breakpoint regions of the --Sciacca and --Puglia, respectively, are about 10 and 165 kb long, and revealed the presence of repeats that most likely impaired the amplification of a specific fragment for the identification of the breakpoint. MLPA, in association with qRT-PCR and long-range PCR, is a good approach for the identification and molecular characterization of rare or new deletions. Breakpoint analysis confirms that Alu sequences play an important role in favoring unequal crossing-over. Southern Italy shows considerable genetic heterogeneity, as expected with its central position in the Mediterranean basin, favoring migratory flows.


Assuntos
Talassemia alfa , Humanos , Talassemia alfa/genética , alfa-Globinas/genética , Família Multigênica , Reação em Cadeia da Polimerase Multiplex , Itália
20.
Int J Mol Sci ; 24(3)2023 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-36769196

RESUMO

Acromegaly is a chronic systemic disease caused in the vast majority of cases by growth hormone (GH)-secreting adenoma, with surgery being the first-line treatment. When a cure is not attained with surgery, first-generation somatostatin receptor ligands (fg-SRLs) are the most common medication prescribed. Predictors of response to fg-SRLs have been studied; however, they cannot fully predict the response to fg-SRL. MicroRNAs are small RNAs, the main role of which is messenger RNA (mRNA) post-transcriptional regulation. This study aimed to identify the microRNAs involved in resistance to treatment with fg-SRLs in acromegaly. Ten patients with acromegaly undergoing treatment with fg-SRLs were selected to undergo miRNA sequencing: five controlled and five uncontrolled with treatment. Bioinformatic analysis was performed to detect differentially expressed miRNAs. Then, the same 10 samples were used for validation by qPCR and an additional 22 samples were analyzed, totaling 32 samples. e We found 59 differentially expressed miRNAs in the first analysis. miR-181a-5p and miR-181b-5p were downregulated, and miR-383-5p was upregulated in the uncontrolled group. Receiver operating characteristic (ROC) curve analysis of miR-383-5p showed an NPV of 84.3% and a PPV of 84.5%. In summary, miR-181a-5p, miR-181b-5p, and miR-383-5p are biomarkers of response to fg-SRLs, and they can be used individually or included in prediction models as tools to guide clinical decisions.


Assuntos
Acromegalia , MicroRNAs , Humanos , Acromegalia/genética , Receptores de Somatostatina/genética , MicroRNAs/genética , MicroRNAs/uso terapêutico
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