RESUMO
This article focuses on screening the major secreted proteins by the ischemia-challenged cardiac stromal fibroblasts (CF), the assessment of their expression status and functional role in the post-ischemic left ventricle (LV) and in the ischemia-challenged CF culture and to phenotype CF at single cell resolution based on the positivity of the identified mediators. The expression level of CRSP2, HSP27, IL-8, Cofilin-1, and HSP90 in the LV tissues following coronary artery bypass graft (CABG) and myocardial infarction (MI) and CF cells followed the screening profile derived from the MS/MS findings. The histology data unveiled ECM disorganization, inflammation and fibrosis reflecting the ischemic pathology. CRSP2, HSP27, and HSP90 were significantly upregulated in the LV-CABG tissues with a concomitant reduction ion LV-MI whereas Cofilin-1, IL8, Nrf2, and Troponin I were downregulated in LV-CABG and increased in LV-MI. Similar trends were exhibited by ischemic CF. Single cell transcriptomics revealed multiple sub-phenotypes of CF based on their respective upregulation of CRSP2, HSP27, IL-8, Cofilin-1, HSP90, Troponin I and Nrf2 unveiling pathological and pro-healing phenotypes. Further investigations regarding the underlying signaling mechanisms and validation of sub-populations would offer novel translational avenues for the management of cardiac diseases.
Assuntos
Fibroblastos , Infarto do Miocárdio , Análise de Célula Única , Infarto do Miocárdio/metabolismo , Infarto do Miocárdio/genética , Infarto do Miocárdio/patologia , Fibroblastos/metabolismo , Humanos , Células Estromais/metabolismo , Interleucina-8/metabolismo , Interleucina-8/genética , Perfilação da Expressão Gênica , Proteínas de Choque Térmico HSP90/metabolismo , Proteínas de Choque Térmico HSP90/genética , Proteínas de Choque Térmico HSP27/metabolismo , Proteínas de Choque Térmico HSP27/genética , Cofilina 1/metabolismo , Cofilina 1/genética , Masculino , Miocárdio/metabolismo , Miocárdio/patologia , Transcriptoma , Fator 2 Relacionado a NF-E2/metabolismo , Fator 2 Relacionado a NF-E2/genéticaRESUMO
Oxidative stress on cysteine (Cys)-containing proteins has been associated with physiological disorders, as suggested for the human cofilin-1 (CFL-1) protein, in which the oxidized residues are likely implicated in the aggregation process of α-synuclein, leading to severe neuronal injuries. Considering the relevance of the oxidation state of cysteine, quantification of thiols may offer a guide for the development of effective therapies. This work presents, for the very first time, thiol quantification within CFL-1 in solution and on the surface following classic and adapted versions of Ellman's assay. The 1:1 stoichiometric Ellman's reaction occurs between 5,5'-dithio-bis(2-nitrobenzoic acid) (DTNB), and the free thiol of the cysteine residue, producing two 2-nitro-5-thiobenzoate (TNB2-) ions, one of which is released into the medium. While in solution, the thiol concentration was determined by the absorbance of the released TNB2-, on the surface, the mass of the attached TNB2- ion to the protein allowed the quantification by means of the multiparametric surface plasmon resonance (MP-SPR) technique. The SPR angle change after the interaction of DTNB with immobilized CFL-1 gave a surface coverage of 26.5 pmol cm-2 for the TNB2- ions (ΓTNB2-). The ratio of this value to the surface coverage of CFL-1, ΓCFL-1 = 6.5 ± 0.6 pmol cm-2 (also determined by MP-SPR), gave 4.1 as expected for this protein, i.e., CFL-1 contains four Cys residues in its native form (reduced state). A control experiment with adsorbed oxidized protein showed no SPR angle change, thus proving the reliability of adapting Ellman's assay to the surface using the MP-SPR technique. The results presented in this work provide evidence of the heterogenization of Ellman's assay, offering a novel perspective for studying thiol-containing species within proteins. This may be particularly useful to ensure further studies on drug-like molecules that can be carried out with validated oxidized or reduced CFL-1 or other analogous systems.
Assuntos
Cofilina 1 , Compostos de Sulfidrila , Ressonância de Plasmônio de Superfície , Ressonância de Plasmônio de Superfície/métodos , Humanos , Compostos de Sulfidrila/química , Compostos de Sulfidrila/análise , Cofilina 1/química , Cofilina 1/metabolismo , Ácido Ditionitrobenzoico/química , Propriedades de Superfície , Cisteína/química , Cisteína/análiseRESUMO
Prevalence of metabolic dysfunction-associated steatotic liver disease (MASLD), formerly known as non-alcoholic fatty liver disease, increases worldwide and associates with type 2 diabetes and other cardiometabolic diseases. Here we demonstrate that Sema3a is elevated in liver sinusoidal endothelial cells of animal models for obesity, type 2 diabetes and MASLD. In primary human liver sinusoidal endothelial cells, saturated fatty acids induce expression of SEMA3A, and loss of a single allele is sufficient to reduce hepatic fat content in diet-induced obese mice. We show that semaphorin-3A regulates the number of fenestrae through a signaling cascade that involves neuropilin-1 and phosphorylation of cofilin-1 by LIM domain kinase 1. Finally, inducible vascular deletion of Sema3a in adult diet-induced obese mice reduces hepatic fat content and elevates very low-density lipoprotein secretion. Thus, we identified a molecular pathway linking hyperlipidemia to microvascular defenestration and early development of MASLD.
Assuntos
Células Endoteliais , Fígado , Camundongos Endogâmicos C57BL , Hepatopatia Gordurosa não Alcoólica , Semaforina-3A , Transdução de Sinais , Animais , Humanos , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Fígado/metabolismo , Fígado/patologia , Hepatopatia Gordurosa não Alcoólica/metabolismo , Hepatopatia Gordurosa não Alcoólica/patologia , Hepatopatia Gordurosa não Alcoólica/genética , Semaforina-3A/metabolismo , Semaforina-3A/genética , Neuropilina-1/metabolismo , Neuropilina-1/genética , Obesidade/metabolismo , Obesidade/patologia , Obesidade/genética , Cofilina 1/metabolismo , Cofilina 1/genética , Modelos Animais de Doenças , Masculino , Fosforilação , Células Cultivadas , Camundongos , Camundongos Knockout , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/patologia , Diabetes Mellitus Tipo 2/genética , Dieta Hiperlipídica/efeitos adversosRESUMO
OBJECTIVE: In this study, we investigated the mechanism of action of LIMK1 in cervical cancer progression. METHODS: The biological role of LIMK1 in regulating the growth, invasion, and metastasis of cervical cancer was studied in SiHa, CaSki cells and nude mice tumor models. The role of LIMK1 in the growth of cervical cancer was evaluated by HE staining. The role of LIMK1 in the invasion, metastasis, and proliferation of cervical cancer was evaluated by cell scratch, Transwell, and monoclonal experiments. The interaction among LIMK1, ROS, and Src was evaluated by Western blotting. The effects of regulating ROS and p-Src expression on LIMK1 in the migration/invasion and proliferation of cervical cancer cells were evaluated through cellular functional assays. RESULTS: Overexpression of LIMK1 promoted tumor growth in nude mice. Cell scratch, Transwell, and monoclonal experiments suggested that LIMK1 promoted the invasion, metastasis, and proliferation of cervical cancer cells. Western blotting suggested that LIMK1 can promote the expression of ROS-related proteins NOX2, NOX4, p-Src, and downstream proteins p-FAK, p-ROCK1/2, p-Cofilin-1, F-actin and inhibit the expression of p-SHP2 protein. Correction experiments showed that LIMK1 regulated the expression of p-FAK and p-Cofilin-1 proteins by regulating ROS and p-Src. Through the detection of cervical cancer cell functions, it was found that the activation of ROS and p-Src induced by LIMK1 is an early event that promotes the migration, proliferation, and invasion of cervical cancer cells. CONCLUSIONS: LIMK1 promotes the expression of F-actin and promotes the development of cervical cancer by regulating the oxidative stress/Src-mediated p-FAK/p-ROCK1/2/p-Cofilin-1 pathway.
Assuntos
Quinases Lim , Camundongos Nus , Espécies Reativas de Oxigênio , Transdução de Sinais , Neoplasias do Colo do Útero , Neoplasias do Colo do Útero/metabolismo , Neoplasias do Colo do Útero/patologia , Neoplasias do Colo do Útero/genética , Quinases Lim/metabolismo , Quinases Lim/genética , Animais , Feminino , Espécies Reativas de Oxigênio/metabolismo , Humanos , Linhagem Celular Tumoral , Camundongos , Proliferação de Células , Quinase 1 de Adesão Focal/metabolismo , Quinase 1 de Adesão Focal/genética , Regulação para Cima , Quinases da Família src/metabolismo , Quinases da Família src/genética , Movimento Celular/genética , Fatores de Despolimerização de Actina/metabolismo , Fatores de Despolimerização de Actina/genética , Invasividade Neoplásica , Regulação Neoplásica da Expressão Gênica , Cofilina 1/metabolismo , Cofilina 1/genéticaRESUMO
PURPOSE: The purpose of this study was to explore the expression, prognostic value and immune correlation of Cofilin 1 protein(CFL-1) in head and neck squamous cell carcinoma(HNSCC). METHODS: The expression and prognostic value of CFL-1 in head and neck squamous cell carcinoma(HNSCC) was explored in the cancer genome map database (TCGA) and gene expression total databases (GEO), and the potential immune pathway of CFL-1 in HNSCC was revealed by GESA and cibersoft analysis. The data were statistically analyzed using SPSS 26.0 software package. RESULTS: CFL-1 was significantly up-regulated in HNSCC tissue. The expression level of CFL-1 was significantly correlated with the overall survival status of HNSCC. High expression of CFL-1 was significantly associated with a lower overall survival rate. In addition, multivariate Cox survival analysis showed that CFL-1 expression was independent predictors of poor prognosis of HNSCC. GESA and cibersoft analysis showed that the imbalance of CFL-1 expression affected multiple signal pathways and infiltration of immune cells. CONCLUSIONS: CFL-1 is highly expressed in HNSCC and is significantly associated with poor prognosis of NHSCC. It is a potential prognostic marker of HNSCC.
Assuntos
Cofilina 1 , Neoplasias de Cabeça e Pescoço , Carcinoma de Células Escamosas de Cabeça e Pescoço , Humanos , Prognóstico , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço/mortalidade , Carcinoma de Células Escamosas de Cabeça e Pescoço/imunologia , Cofilina 1/genética , Cofilina 1/metabolismo , Neoplasias de Cabeça e Pescoço/genética , Neoplasias de Cabeça e Pescoço/mortalidade , Neoplasias de Cabeça e Pescoço/metabolismo , Taxa de Sobrevida , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Modelos de Riscos ProporcionaisRESUMO
Peroxiredoxin 1 (PRDX1) is an important member of the peroxiredoxin family (PRDX) and is upregulated in a variety of tumors. Previous studies have found that high PRDX1 expression is closely related to the metastasis of oral squamous cell carcinoma (OSCC), but the specific molecular mechanism is elusive. To elucidate the role of PRDX1 in the metastasis process of OSCC, we evaluated the expression of PRDX1 in OSCC clinical specimens and its impact on the prognosis of OSCC patients. Then, the effect of PRDX1 on OSCC metastasis and cytoskeletal reconstruction was explored in vitro and in nude mouse tongue cancer models, and the molecular mechanisms were also investigated. PRDX1 can directly interact with the actin-binding protein Cofilin, inhibiting the phosphorylation of its Ser3 site, accelerating the depolymerization and turnover of actin, promoting OSCC cell movement, and aggravating the invasion and metastasis of OSCC. In clinical samples and mouse tongue cancer models, PRDX1 also increased lymph node metastasis of OSCC and was negatively correlated with the phosphorylation of Cofilin; PRDX1 also reduced the overall survival rate of OSCC patients. In summary, our study identified that PRDX1 may be a potential therapeutic target to inhibit OSCC metastasis.
Assuntos
Carcinoma de Células Escamosas , Camundongos Nus , Neoplasias Bucais , Peroxirredoxinas , Animais , Feminino , Humanos , Masculino , Camundongos , Pessoa de Meia-Idade , Fatores de Despolimerização de Actina/metabolismo , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/secundário , Linhagem Celular Tumoral , Movimento Celular , Cofilina 1/metabolismo , Regulação Neoplásica da Expressão Gênica , Metástase Linfática , Camundongos Endogâmicos BALB C , Neoplasias Bucais/patologia , Neoplasias Bucais/metabolismo , Neoplasias Bucais/genética , Peroxirredoxinas/metabolismo , Peroxirredoxinas/genética , Fosforilação , Prognóstico , Neoplasias da Língua/patologia , Neoplasias da Língua/metabolismo , Neoplasias da Língua/genéticaRESUMO
Within the bloodstream, monocytes must traverse the microvasculature to prevent leukostasis, which is the entrapment of monocytes within the confines of the microvasculature. Using the model cell line, THP-1, and VCAM-1 coated channels to simulate the microvasculature surface, we demonstrate that monocytes predominantly adopt an amoeboid phenotype, which is characterized by the formation of blebs. As opposed to cortical actin flow in leader blebs, cell movement is correlated with myosin contraction at the cell rear. It was previously documented that cofilin-1 promotes cortical actin turnover at leader bleb necks in melanoma cells. In monocytes, our data suggest that cofilin-1 promotes the local upregulation of myosin contractility through actin cytoskeleton remodeling. In support of this concept, cofilin-1 is found to localize to a single cell edge. Moreover, the widespread upregulation of myosin contractility was found to inhibit migration. Thus, monocytes within the microvasculature may avoid entrapment by adopting an amoeboid mode of migration.
Assuntos
Citoesqueleto de Actina , Movimento Celular , Cofilina 1 , Monócitos , Humanos , Citoesqueleto de Actina/metabolismo , Actinas/metabolismo , Cofilina 1/metabolismo , Monócitos/metabolismo , Miosinas/metabolismo , Células THP-1 , Molécula 1 de Adesão de Célula Vascular/metabolismoRESUMO
Intracellular actin networks assemble through the addition of ATP-actin subunits at the growing barbed ends of actin filaments. This is followed by "aging" of the filament via ATP hydrolysis and subsequent phosphate release. Aged ADP-actin subunits thus "treadmill" through the filament before being released back into the cytoplasmic monomer pool as a result of depolymerization at filament pointed ends. The necessity for aging before filament disassembly is reinforced by preferential binding of cofilin to aged ADP-actin subunits over newly-assembled ADP-Pi actin subunits in the filament. Consequently, investigations into how cofilin influences pointed-end depolymerization have, thus far, focused exclusively on aged ADP-actin filaments. Using microfluidics-assisted Total Internal Reflection Fluorescence (mf-TIRF) microscopy, we reveal that, similar to their effects on ADP filaments, cofilin and cyclase-associated protein (CAP) also promote pointed-end depolymerization of ADP-Pi filaments. Interestingly, the maximal rates of ADP-Pi filament depolymerization by CAP and cofilin together remain approximately 20-40 times lower than for ADP filaments. Further, we find that the promotion of ADP-Pi pointed-end depolymerization is conserved for all three mammalian cofilin isoforms. Taken together, the mechanisms presented here open the possibility of newly-assembled actin filaments being directly disassembled from their pointed-ends, thus bypassing the slow step of Pi release in the aging process.
Assuntos
Citoesqueleto de Actina , Actinas , Citoesqueleto de Actina/metabolismo , Animais , Actinas/metabolismo , Fatores de Despolimerização de Actina/metabolismo , Difosfato de Adenosina/metabolismo , Coelhos , Camundongos , Polimerização , Cofilina 1/metabolismoRESUMO
Cofilin, a key actin-binding protein, orchestrates the dynamics of the actomyosin network through its actin-severing activity and by promoting the recycling of actin monomers. Recent experiments suggest that cofilin forms functionally distinct oligomers via thiol post-translational modifications (PTMs) that promote actin nucleation and assembly. Despite these advances, the structural conformations of cofilin oligomers that modulate actin activity remain elusive because there are combinatorial ways to oxidize thiols in cysteines to form disulfide bonds rapidly. This study employs molecular dynamics simulations to investigate human cofilin 1 as a case study for exploring cofilin dimers via disulfide bond formation. Utilizing a biasing scheme in simulations, we focus on analyzing dimer conformations conducive to disulfide bond formation. Additionally, we explore potential PTMs arising from the examined conformational ensemble. Using the free energy profiling, our simulations unveil a range of probable cofilin dimer structures not represented in current Protein Data Bank entries. These candidate dimers are characterized by their distinct population distributions and relative free energies. Of particular note is a dimer featuring an interface between cysteines 139 and 147 residues, which demonstrates stable free energy characteristics and intriguingly symmetrical geometry. In contrast, the experimentally proposed dimer structure exhibits a less stable free energy profile. We also evaluate frustration quantification based on the energy landscape theory in the protein-protein interactions at the dimer interfaces. Notably, the 39-39 dimer configuration emerges as a promising candidate for forming cofilin tetramers, as substantiated by frustration analysis. Additionally, docking simulations with actin filaments further evaluate the stability of these cofilin dimer-actin complexes. Our findings thus offer a computational framework for understanding the role of thiol PTM of cofilin proteins in regulating oligomerization, and the subsequent cofilin-mediated actin dynamics in the actomyosin network.
Assuntos
Citoesqueleto de Actina , Dissulfetos , Simulação de Dinâmica Molecular , Dissulfetos/química , Humanos , Citoesqueleto de Actina/química , Citoesqueleto de Actina/metabolismo , Cofilina 1/química , Cofilina 1/metabolismo , Multimerização Proteica , Actinas/química , Actinas/metabolismo , Fatores de Despolimerização de Actina/química , Fatores de Despolimerização de Actina/metabolismo , TermodinâmicaRESUMO
The anti-tumor capacity of natural killer (NK) cells heavily relies on their ability to migrate towards their target cells. This process is based on dynamic actinrearrangement, so-called actin treadmilling, andis tightly regulated by proteins such as cofilin-1. The aim of the present study was to identify the role of cofilin-1 (CFL-1) in the migratory behavior of NK cells and to investigate a possible impact of an obesity-associated micromilieu on these cells, as it is known that obesity correlates with various impaired NK cell functions. CFL-1 was knocked-down via transfection of NK-92 cells with respective siRNAs. Obesity associated micromilieu was mimicked by incubation of NK-92 cells with adipocyte-conditioned medium from human preadipocyte SGBS cells or leptin. Effects on CFL-1 levels, the degree of phosphorylation to the inactive pCFL-1 as well as NK-92 cell motility were analyzed. Surprisingly, siRNA-mediated CFL-1 knockdown led to a significant increase of migration, as determined by enhanced velocity and accumulated distance of migration. No effect on CFL-1 nor pCFL-1 expression levels, proportion of phosphorylation and cell migratory behavior could be demonstrated under the influence of an obesity-associated microenvironment. In conclusion, the results indicate a significant effect of a CFL-1 knockdown on NK cell motility.
Assuntos
Movimento Celular , Cofilina 1 , Técnicas de Silenciamento de Genes , Células Matadoras Naturais , Obesidade , RNA Interferente Pequeno , Humanos , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/metabolismo , Movimento Celular/genética , Cofilina 1/metabolismo , Cofilina 1/genética , Obesidade/metabolismo , Obesidade/genética , Obesidade/imunologia , RNA Interferente Pequeno/genética , Fosforilação , Linhagem Celular , Adipócitos/metabolismo , Leptina/metabolismo , Microambiente Celular , Meios de Cultivo Condicionados/farmacologiaRESUMO
Cofilin family proteins have essential roles in remodeling the cytoskeleton through filamentous actin depolymerization and severing. The short, unstructured N-terminal region of cofilin is critical for actin binding and harbors the major site of inhibitory phosphorylation. Atypically for a disordered sequence, the N-terminal region is highly conserved, but specific aspects driving this conservation are unclear. Here, we screen a library of 16,000 human cofilin N-terminal sequence variants for their capacity to support growth in S. cerevisiae in the presence or absence of the upstream regulator LIM kinase. Results from the screen and biochemical analysis of individual variants reveal distinct sequence requirements for actin binding and regulation by LIM kinase. LIM kinase recognition only partly explains sequence constraints on phosphoregulation, which are instead driven to a large extent by the capacity for phosphorylation to inactivate cofilin. We find loose sequence requirements for actin binding and phosphoinhibition, but collectively they restrict the N-terminus to sequences found in natural cofilins. Our results illustrate how a phosphorylation site can balance potentially competing sequence requirements for function and regulation.
Assuntos
Actinas , Cofilina 1 , Humanos , Citoesqueleto de Actina/metabolismo , Fatores de Despolimerização de Actina/metabolismo , Actinas/metabolismo , Cofilina 1/genética , Cofilina 1/metabolismo , Quinases Lim/metabolismo , Fosforilação , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismoRESUMO
To mount an adaptive immune response, dendritic cells must migrate to lymph nodes to present antigens to T cells. Critical to 3D migration is the nucleus, which is the size-limiting barrier for migration through the extracellular matrix. Here, we show that inflammatory activation of dendritic cells leads to the nucleus becoming spherically deformed and enables dendritic cells to overcome the typical 2- to 3-µm diameter limit for 3D migration through gaps in the extracellular matrix. We show that the nuclear shape change is partially attained through reduced cell adhesion, whereas improved 3D migration is achieved through reprogramming of the actin cytoskeleton. Specifically, our data point to a model whereby the phosphorylation of cofilin-1 at serine 41 drives the assembly of a cofilin-actomyosin ring proximal to the nucleus and enhances migration through 3D collagen gels. In summary, these data describe signaling events through which dendritic cells deform their nucleus and enhance their migratory capacity.
Assuntos
Fatores de Despolimerização de Actina , Actomiosina , Fatores de Despolimerização de Actina/metabolismo , Movimento Celular/fisiologia , Actomiosina/metabolismo , Citocinese , Cofilina 1/metabolismo , Matriz Extracelular/metabolismo , Células Dendríticas/metabolismoRESUMO
BACKGROUND: Primary Sjögren's syndrome (pSS) is a chronic systemic autoimmune disease. There is no relevant research on whether the migratory ability of bone marrow mesenchymal stem cells (BM-MSC) is impaired in patients with pSS (pSS-BMMSC). METHODS: Trajectories and velocities of BM-MSC were analyzed. Transwell migration assay and wound healing assay were used to investigate the migratory capacity of BM-MSC. The proliferative capacity of BM-MSC was evaluated by EDU and CCK8 assay. RNA-seq analysis was then performed to identify the underlying mechanism of lentivirus-mediated cofilin-1 overexpression BM-MSC (BMMSCCFL1). The therapeutic efficacy of BMMSCCFL1 was evaluated in NOD mice. RESULTS: The migratory capacity of pSS-BMMSC was significantly reduced compared to normal volunteers (HC-BMMSC). The expression of the motility-related gene CFL1 was decreased in pSS-BMMSC. Lentivirus-mediated CFL1 overexpression of pSS-BMMSC promoted the migration capacity of pSS-BMMSC. Furthermore, RNA-seq revealed that CCR1 was the downstream target gene of CFL1. To further elucidate the mechanism of CFL1 in regulating BM-MSC migration and proliferation via the CCL5/CCR1 axis, we performed a rescue experiment using BX431 (a CCR1-specific inhibitor) to inhibit CCR1. The results showed that CCR1 inhibitors suppressed the migration and proliferation capacity of MSC induced by CFL1. CONCLUSION: The pSS-BMMSC leads to impaired migration and proliferation, and overexpression of CFL1 can rescue the functional deficiency and alleviate disease symptoms in NOD mice. Mechanically, CFL1 can regulate the expression level of the downstream CCL5/CCR1 axis to enhance the migration and proliferation of BM-MSC.
Assuntos
Células-Tronco Mesenquimais , Síndrome de Sjogren , Camundongos , Animais , Humanos , Camundongos Endogâmicos NOD , Síndrome de Sjogren/metabolismo , Cicatrização , Células-Tronco Mesenquimais/metabolismo , Células da Medula Óssea/metabolismo , Cofilina 1/metabolismo , Receptores CCR1/genética , Receptores CCR1/metabolismoRESUMO
The molecular mechanisms mediating the aggregation and transmission of tau in AD remain unclear. Here, we show that the actin-binding protein cofilin is cleaved by a cysteine protease asparagine endopeptidase (AEP) at N138 in the brains of patients with AD. The AEP-generated cofilin 1-138 fragment interacts with tau and promotes its aggregation. The mixed fibrils consisting of cofilin 1-138 and tau are more pathogenic to cells than pure tau fibrils. Furthermore, overexpression of cofilin 1-138 in the brain facilitates the propagation of pathological tau aggregates and promotes AD-like cognitive impairments in tau P301S mice. However, mice infected with adeno-associated viruses (AAVs) encoding an AEP-uncleavable cofilin mutant show attenuated tau pathology and cognitive impairments compared with mice injected with AAVs encoding wild-type cofilin. Together, these observations support the role of the cofilin 1-138 fragment in the aggregation and transmission of tau pathology during the onset and progression of AD.
Assuntos
Doença de Alzheimer , Animais , Humanos , Camundongos , Fatores de Despolimerização de Actina/metabolismo , Doença de Alzheimer/metabolismo , Encéfalo/metabolismo , Cofilina 1/metabolismo , Modelos Animais de Doenças , Camundongos Transgênicos , Proteínas tau/metabolismoRESUMO
BACKGROUND: Air pollutants exacerbate chronic airway diseases, such as asthma and chronic obstructive pulmonary disease (COPD). However, the underlying mechanisms are yet to be determined. While a number of studies have reported adverse effects of nanoparticles on humans, little is known about their effects on the respiratory system. OBJECTIVES: To examine the protein expression in human lung microvascular endothelial cells (HMVEC-L) exposed to titanium dioxide (TiO2) nanoparticles, a common air pollutant. MATERIAL AND METHODS: A proteomics approach using two-dimensional polyacrylamide gel electrophoresis (2D-PAGE) and matrix-assisted laser desorption/ionization time-of-flight/time-of-flight mass spectrometry (MALDI-TOF/TOF MS) was used to determine the differences in protein expression at 8 h and 24 h, following the treatment of HMVEC-L with 20-µM or 40-µM TiO2 nanoparticles. RESULTS: Human lung microvascular endothelial cells treated with 20-µM TiO2 nanoparticles showed alterations of 7 protein spots, including molecules related to calcium regulation, transport, cytoskeleton, and muscle contraction. The treatment of HMVEC-L with 40-µM TiO2 nanoparticles resulted in alterations of 4 protein spots, with molecular functions related to the cytoskeleton, myosin regulation, actin modulation, as well as guanosine diphosphate (GDP) and guanosine triphosphate (GTP) regulation. To validate these results, immunohistochemical staining and western blotting analyses were performed on lung tissues collected from mice exposed to TiO2 nanoparticles. Cofilin-1 and profilin-1 were expressed in the endothelium, epithelium and inflammatory cells, and decreased in lung tissues of TiO2 nanoparticle-exposed mice compared to sham-treated controls. CONCLUSIONS: These results suggest that some of the differentially expressed proteins may play important roles in airway diseases caused by TiO2 nanoparticle exposure.
Assuntos
Cofilina 1 , Células Endoteliais , Nanopartículas , Profilinas , Titânio , Animais , Humanos , Camundongos , Células Endoteliais/efeitos dos fármacos , Pulmão/citologia , Nanopartículas/toxicidade , Profilinas/metabolismo , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Titânio/toxicidade , Cofilina 1/metabolismoRESUMO
The actin cytoskeleton reorganization during sperm capacitation is essential for the occurrence of acrosomal exocytosis (AR) in several mammalian species. Here, we demonstrate that in mouse sperm, within the first minutes of exposure upon capacitating conditions, the activity of RHOA/C and RAC1 is essential for LIMK1 and COFILIN phosphorylation. However, we observed that the signaling pathway involving RAC1 and PAK4 is the main player in controlling actin polymerization in the sperm head necessary for the occurrence of AR. Moreover, we show that the transient phosphorylation of COFILIN is also influenced by the Slingshot family of protein phosphatases (SSH1). The activity of SSH1 is regulated by the dual action of two pathways. On one hand, RHOA/C and RAC1 activity promotes SSH1 phosphorylation (inactivation). On the other hand, the activating dephosphorylation is driven by okadaic acid-sensitive phosphatases. This regulatory mechanism is independent of the commonly observed activating mechanisms involving PP2B and emerges as a new finely tuned modulation that is, so far, exclusively observed in mouse sperm. However, persistent phosphorylation of COFILIN by SSH1 inhibition or okadaic acid did not altered actin polymerization and the AR. Altogether, our results highlight the role of small GTPases in modulating actin dynamics required for AR.
Assuntos
Fatores de Despolimerização de Actina , Capacitação Espermática , Fatores de Despolimerização de Actina/metabolismo , Actinas/metabolismo , Animais , Cofilina 1/metabolismo , Exocitose , Masculino , Mamíferos/metabolismo , Camundongos , Ácido Okadáico/metabolismo , Ácido Okadáico/farmacologia , Fosforilação , Sêmen/metabolismoRESUMO
Actin polymerization dynamics regulated by actin-binding proteins are essential for various cellular functions. The cofilin family of proteins are potent regulators of actin severing and filament disassembly. The structural basis for cofilin-isoform-specific severing activity is poorly understood as their high-resolution structures in complex with filamentous actin (F-actin) are lacking. Here, we present the atomic-resolution structure of the muscle-tissue-specific isoform, cofilin-2 (CFL2), assembled on ADP-F-actin, determined by magic-angle-spinning (MAS) NMR spectroscopy and data-guided molecular dynamics (MD) simulations. We observe an isoform-specific conformation for CFL2. This conformation is the result of a unique network of hydrogen bonding interactions within the α2 helix containing the non-conserved residue, Q26. Our results indicate F-site interactions that are specific between CFL2 and ADP-F-actin, revealing mechanistic insights into isoform-dependent F-actin disassembly.
Assuntos
Actinas , Cofilina 2/química , Citoesqueleto de Actina/metabolismo , Fatores de Despolimerização de Actina/metabolismo , Actinas/metabolismo , Difosfato de Adenosina/metabolismo , Cofilina 1/metabolismo , Cofilina 2/metabolismo , Humanos , Espectroscopia de Ressonância Magnética , Ligação Proteica , Isoformas de Proteínas/metabolismoRESUMO
An inhibitory effect of estradiol (E2) on HIV-1 infection was suggested by several reports. We previously identified increased gene expression of actin-binding protein cofilin 1 (CFL1) in endocervix in the E2-dominated proliferative phase of the menstrual cycle. Actin cytoskeleton has an integral role in establishing and spreading HIV-1 infection. Herein, we studied in vitro effects of E2 on HIV-1 infection and on CFL1 expression to gain insight into the mechanism of HIV-1 inhibition by E2. E2 dose-dependently inhibited HIV-1BaL infection in peripheral blood mononuclear cells (PBMCs) and endocervix. In PBMCs and endocervix, E2 increased protein expression of total CFL1 and phosphorylated CFL1 (pCFL1) and pCFL1/CFL1 ratios. LIMKi3, a LIM kinase 1 and 2 inhibitor, abrogated the phenotype and restored infection in both PBMCs and endocervix; inhibited E2-induced expression of total CFL1, pCFL1; and decreased pCFL1/CFL1 ratios. Knockdown of CFL1 in PBMCs also abrogated the phenotype and partially restored infection. Additional analysis of soluble mediators revealed decreased concentrations of pro-inflammatory chemokines CXCL10 and CCL5 in infected tissues incubated with E2. Our results suggest a link between E2-mediated anti-HIV-1 activity and expression of CFL1 in PBMCs and endocervical mucosa. The data support exploration of cytoskeletal signaling pathway targets for the development of prevention strategies against HIV-1.
Assuntos
Cofilina 1 , Estradiol , Infecções por HIV , Soropositividade para HIV , Cofilina 1/metabolismo , Estradiol/farmacologia , Feminino , HIV-1 , Humanos , Leucócitos Mononucleares/metabolismo , Mucosa/metabolismoRESUMO
BACKGROUND AND AIMS: Intrahepatic cholangiocarcinoma (ICC) is not fully investigated, and how stromal cells contribute to ICC formation is poorly understood. We aimed to uncover ICC origin, cellular heterogeneity, and critical modulators during ICC initiation/progression, and to decipher how fibroblast and endothelial cells in the stromal compartment favor ICC progression. APPROACH AND RESULTS: We performed single-cell RNA sequencing (scRNA-seq) using AKT/Notch intracellular domain-induced mouse ICC tissues at early, middle, and late stages. We analyzed the transcriptomic landscape, cellular classification and evolution, and intercellular communication during ICC initiation/progression. We confirmed the findings using quantitative real-time PCR, western blotting, immunohistochemistry or immunofluorescence, and gene knockout/knockdown analysis. We identified stress-responding and proliferating subpopulations in late-stage mouse ICC tissues and validated them using human scRNA-seq data sets. By integrating weighted correlation network analysis and protein-protein interaction through least absolute shrinkage and selection operator regression, we identified zinc finger, MIZ-type containing 1 (Zmiz1) and Y box protein 1 (Ybx1) as core transcription factors required by stress-responding and proliferating ICC cells, respectively. Knockout of either one led to the blockade of ICC initiation/progression. Using two other ICC mouse models (YAP/AKT, KRAS/p19) and human ICC scRNA-seq data sets, we confirmed the orchestrating roles of Zmiz1 and Ybx1 in ICC occurrence and development. In addition, hes family bHLH transcription factor 1, cofilin 1, and inhibitor of DNA binding 1 were identified as driver genes for ICC. Moreover, periportal liver sinusoidal endothelial cells could differentiate into tip endothelial cells to promote ICC development, and this was Dll4-Notch4-Efnb2 signaling-dependent. CONCLUSIONS: Stress-responding and ICC proliferating subtypes were identified, and Zmiz1 and Ybx1 were revealed as core transcription factors in these subtypes. Fibroblast-endothelial cell interaction promotes ICC development.
Assuntos
Neoplasias dos Ductos Biliares , Colangiocarcinoma , Humanos , Camundongos , Animais , Neoplasias dos Ductos Biliares/patologia , Cofilina 1/genética , Cofilina 1/metabolismo , Transcriptoma , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteína 1 de Ligação a Y-Box/metabolismo , Células Endoteliais/metabolismo , Proteínas Proto-Oncogênicas p21(ras)/genética , Camundongos Knockout , Colangiocarcinoma/patologia , Ductos Biliares Intra-Hepáticos/patologia , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , DNA/metabolismo , Linhagem Celular TumoralRESUMO
The cofilin-1 protein, encoded by CFL1, is an actin-binding protein that regulates F-actin depolymerization and nucleation activity through phosphorylation and dephosphorylation. CFL1 has been implicated in the development of neurodegenerative diseases (Alzheimer's disease and Huntington's disease), neuronal migration disorders (lissencephaly, epilepsy, and schizophrenia), and neural tube closure defects. Mutations in CFL1 have been associated with impaired neural crest cell migration and neural tube closure defects. In our study, various computational approaches were utilized to explore single-nucleotide polymorphisms (SNPs) in CFL1. The Variation Viewer and gnomAD databases were used to retrieve CFL1 SNPs, including 46 nonsynonymous SNPs (nsSNPs). The functional and structural annotation of SNPs was performed using 12 sequence-based web applications, which identified 20 nsSNPs as being the most likely to be deleterious or disease-causing. The conservation of cofilin-1 protein structures was illustrated using the ConSurf and PROSITE web servers, which projected the 12 most deleterious nsSNPs onto conserved domains, with the potential to disrupt the protein's functionality. These 12 nsSNPs were selected for protein structure construction, and the DynaMut/DUET servers predicted that the protein variants V7G, L84P, and L99A were the most likely to be damaging to the cofilin-1 protein structure or function. The evaluation of molecular docking studies demonstrated that the L99A and L84P cofilin-1 variants reduce the binding affinity for actin compared with the native cofilin-1 structure, and molecular dynamic simulation studies confirmed that these variants might destabilize the protein structure. The consequences of putative mutations on protein-protein interactions and post-translational modification sites in the cofilin-1 protein structure were analyzed. This study represents the first complete approach to understanding the effects of nsSNPs within the actin-depolymerizing factor/cofilin family, which suggested that SNPs resulting in L84P (rs199716082) and L99A (rs267603119) variants represent significant CFL1 mutations associated with disease development.