RESUMO
During cotranslational translocation, the signal peptide of a nascent chain binds Sec61 translocon to initiate protein transport through the endoplasmic reticulum (ER) membrane. Our cryo-electron microscopy structure of ribosome-Sec61 shows binding of an ordered heterotetrameric translocon-associated protein (TRAP) complex, in which TRAP-γ is anchored at two adjacent positions of 28S ribosomal RNA and interacts with ribosomal protein L38 and Sec61α/γ. Four transmembrane helices (TMHs) of TRAP-γ cluster with one C-terminal helix of each α, ß, and δ subunits. The seven TMH bundle helps position a crescent-shaped trimeric TRAP-α/ß/δ core in the ER lumen, facing the Sec61 channel. Further, our in vitro assay establishes the cyclotriazadisulfonamide derivative CK147 as a translocon inhibitor. A structure of ribosome-Sec61-CK147 reveals CK147 binding the channel and interacting with the plug helix from the lumenal side. The CK147 resistance mutations surround the inhibitor. These structures help in understanding the TRAP functions and provide a new Sec61 site for designing translocon inhibitors.
Assuntos
Proteínas de Ligação ao Cálcio , Ribossomos , Canais de Translocação SEC , Microscopia CrioeletrônicaRESUMO
BACKGROUND: Altered microRNA profiles have been observed not only in tumour tissues but also in biofluids, where they circulate in a stable form thus representing interesting biomarker candidates. This study aimed to identify a microRNA signature as a non-invasive biomarker and to investigate its impact on glioma biology. METHODS: MicroRNAs were selected using a global expression profile in preoperative serum samples from 37 glioma patients. Comparison between serum samples from age and gender-matched controls was performed by using the droplet digital PCR. The ROC curve and Kaplan-Meier survival analyses were used to evaluate the diagnostic/prognostic values. The functional role of the identified signature was assessed by gain/loss of function strategies in glioma cells. RESULTS: A three-microRNA signature (miR-1-3p/-26a-1-3p/-487b-3p) was differentially expressed in the serum of patients according to the isocitrate dehydrogenase (IDH) genes mutation status and correlated with both patient Overall and Progression Free Survival. The identified signature was also downregulated in the serum of patients compared to controls. Consistent with these results, the signature expression and release in the conditioned medium of glioma cells was lower in IDH-wild type cells compared to the mutated counterpart. Furthermore, in silico analysis of glioma datasets showed a consistent deregulation of the signature according to the IDH mutation status in glioma tumour tissues. Ectopic expression of the signature negatively affects several glioma functions. Notably, it impacts the glioma invasive phenotype by directly targeting the invadopodia-related proteins TKS4, TKS5 and EFHD2. CONCLUSIONS: We identified a three microRNA signature as a promising complementary or even an independent non-invasive diagnostic/prognostic biomarker. The signature displays oncosuppressive functions in glioma cells and impacts on proteins crucial for migration and invasion, providing potential targets for therapeutic intervention.
Assuntos
Neoplasias Encefálicas , MicroRNA Circulante , Glioma , MicroRNAs , Humanos , Neoplasias Encefálicas/patologia , Biomarcadores Tumorais/genética , Glioma/patologia , MicroRNAs/genética , Prognóstico , Isocitrato Desidrogenase/genética , Proteínas Adaptadoras de Transporte Vesicular/metabolismo , Proteínas de Ligação ao CálcioRESUMO
Copy number variations (CNVs) in the Neurexin 1 (NRXN1) gene, which encodes a presynaptic protein involved in neurotransmitter release, are some of the most frequently observed single-gene variants associated with autism spectrum disorder (ASD). To address the functional contribution of NRXN1 CNVs to behavioral phenotypes relevant to ASD, we carried out systematic behavioral phenotyping of an allelic series of Nrxn1 mouse models: one carrying promoter and exon 1 deletion abolishing Nrxn1α transcription, one carrying exon 9 deletion disrupting Nrxn1α protein translation, and one carrying an intronic deletion with no observable effect on Nrxn1α expression. We found that homozygous loss of Nrxn1α resulted in enhanced aggression in males, reduced affiliative social behaviors in females, and significantly altered circadian activities in both sexes. Heterozygous or homozygous loss of Nrxn1α affected the preference for social novelty in male mice, and notably, enhanced repetitive motor skills and motor coordination in both sexes. In contrast, mice bearing an intronic deletion of Nrxn1 did not display alterations in any of the behaviors assessed. These findings demonstrate the importance of Nrxn1α gene dosage in regulating social, circadian, and motor functions, and the variables of sex and genomic positioning of CNVs in the expression of autism-related phenotypes. Importantly, mice with heterozygous loss of Nrxn1, as found in numerous autistic individuals, show an elevated propensity to manifest autism-related phenotypes, supporting the use of models with this genomic architecture to study ASD etiology and assess additional genetic variants associated with autism.
Assuntos
Transtorno do Espectro Autista , Proteínas de Ligação ao Cálcio , Moléculas de Adesão de Célula Nervosa , Animais , Feminino , Masculino , Camundongos , Transtorno do Espectro Autista/genética , Variações do Número de Cópias de DNA/genética , Fenótipo , Comportamento Social , Moléculas de Adesão de Célula Nervosa/genética , Proteínas de Ligação ao Cálcio/genéticaRESUMO
Background: Lung adenocarcinoma (LUAD) is a heterogeneous disease with a dismal prognosis for advanced tumors. Immune-associated cells in the microenvironment substantially impact LUAD formation and progression, which has gained increased attention in recent decades. Sphingolipids have a profound impact on tumor formation and immune infiltration. However, few researchers have focused on the utilization of sphingolipid variables in the prediction of LUAD prognosis. The goal of this work was to identify the major sphingolipid-related genes (SRGs) in LUAD and develop a valid prognostic model based on SRGs. Methods: The most significant genes for sphingolipid metabolism (SM) were identified using the AUCell and WGCNA algorithms in conjunction with single-cell and bulk RNA-seq. LASSO and COX regression analysis was used to develop risk models, and patients were divided into high-and low-risk categories. External nine provided cohorts evaluated the correctness of the models. Differences in immune infiltration, mutation landscape, pathway enrichment, immune checkpoint expression, and immunotherapy were also further investigated in distinct subgroups. Finally, cell function assay was used to verify the role of CACYBP in LUAD cells. Results: A total of 334 genes were selected as being most linked with SM activity for further investigation, and a risk model consisting of 11 genes was established using lasso and cox regression. According to the median risk value, patients were split into high- and low-risk groups, and the high-risk group had a worse prognosis. The low-risk group had more immune cell infiltration and higher expression of immune checkpoints, which illustrated that the low-risk group was more likely to benefit from immunotherapy. It was verified that CACYBP could increase the ability of LUAD cells to proliferate, invade, and migrate. Conclusion: The eleven-gene signature identified in this research may help physicians create individualized care plans for LUAD patients. CACYBP may be a new therapeutic target for patients with advanced LUAD.
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Adenocarcinoma de Pulmão , Neoplasias Pulmonares , Humanos , RNA-Seq , Análise da Expressão Gênica de Célula Única , Adenocarcinoma de Pulmão/genética , Adenocarcinoma de Pulmão/terapia , Metabolismo dos Lipídeos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/terapia , Microambiente Tumoral/genética , Proteínas de Ligação ao CálcioRESUMO
BACKGROUND: At present, immune monotherapy and combination therapy has not shown satisfactory effects on acral melanoma, and still no standard treatment is available for advanced acral melanoma. Here, a phase II trial was performed to explore the safety and efficacy of apatinib combined with camrelizumab in advanced acral melanoma patients as first-line therapy (NCT03955354). METHODS: Patients with pathologically confirmed, locally unresectable or metastatic treatment native acral melanoma received 250 mg apatinib once daily and camrelizumab 200 mg once every two weeks intravenously every 28-day cycle. The primary end-point was objective response rate and the secondary end-points were disease control rate, overall survival, progression-free survival and safety. RESULTS: Thirty patients were recruited between January 2015 and January 2022. Among them, 21 (70.0%) had stage IV, and a median tumour burden was 50 mm (range: 11-187). Objective response rate was 24.1%, and 7 of 29 patients had an anti-tumour response, including partial response (n = 5) and complete response (n = 2). Disease control rate was 82.8%, median progression-free survival was 7.39 months (confidence interval: 3.65-9.92), and median overall survival was 13.4 months (confidence interval: 1.9-25.0). Grade 3-4 treatment-related toxicity (grade 3 50.5%; grade 4 3.3%) included transaminase elevations, proteinuria, leukocytopenia, vomiting, diarrhea and drug-induced liver injury. No treatment-related mortality occurred. The mutations of TTN, MUC16, VPS13D, ALPK2 and SCUBE1 showed significant alterations with survival outcome. CONCLUSIONS: Apatinib combined with camrelizumab showed manageable safety profile and reasonable anti-tumour activity in advanced acral melanoma patients as first-line therapy.
Assuntos
Melanoma , Neoplasias Cutâneas , Humanos , Melanoma/patologia , Neoplasias Cutâneas/patologia , Proteínas de Ligação ao Cálcio , Proteínas , Proteínas QuinasesRESUMO
BACKGROUND: Circular RNAs (circRNAs) and long non-coding RNAs (lncRNAs) have been hypothesized to have important roles in the etiology of hepatocellular carcinoma (HCC). However, the synergistic effect of circRNA and lncRNA in the pathogenesis of HCC has rarely been studied. METHODS: In this study, the Gene Expression Omnibus database was used to get the expression profiles of circRNAs, micro RNAs (miRNAs), lncRNAs, and messenger RNAs (mRNAs) in HCC tissues and normal tissues. The accession numbers for this database are GSE101728, GSE155949, and GSE108724. We found 291 differentially overexpressed lncRNAs and 541 differentially overexpressed mRNA in GSE101728, 30 differentially overexpressed circRNA in GSE155949, and 48 significantly downregulated miRNA in GSE198724. Meanwhile, based on Pearson correlation test, we established lncRNA-mRNA networks. We constructed lncRNA/circRNA-miRNA pairs through Starbase database prediction and identified the common miRNAs. The intersection of co-predicted miRNAs and the 48 significantly low expression miRNAs in GSE198724 were included in the following study. miRDB, Targetscan, miRwalk, and lncRNA-related mRNA jointly determined the miRNA-mRNA portion of the circRNA/lncRNA-miRNA-mRNA co-expression network. And, among 55 differentially expressed mRNA in circRNA/lncRNA-miRNA-mRNA network, CPEB3, EFNB3, FATA4, growth hormone receptor, GSTZ1, KLF8, MFAP4, PAIP2B, PHACTR3, PITPNM3, RPS6KA6, RSPO3, SLITRK6, SMOC1, STEAP4, SYT1, TMEM132E, TSPAN11, and ZFPM2 were intimately related to the prognosis of HCC patients in Kaplan-Meier plotter analysis (P < .05). CONCLUSION: We have discovered that the prognosis-related lncRNAs/circRNAs-miRNA-mRNA network plays a significant role in the pathogenesis of HCC. These findings may offer fresh perspectives for further research into the pathogenesis of HCC and the search for novel treatments for HCC.
Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , MicroRNAs , RNA Longo não Codificante , Humanos , Carcinoma Hepatocelular/patologia , RNA Circular/genética , RNA Mensageiro/metabolismo , RNA Longo não Codificante/genética , RNA-Seq , Neoplasias Hepáticas/patologia , Redes Reguladoras de Genes , Regulação Neoplásica da Expressão Gênica , MicroRNAs/genética , Proteínas de Transporte/genética , Glicoproteínas/metabolismo , Proteínas da Matriz Extracelular/genética , Proteínas de Ligação ao Cálcio/metabolismoRESUMO
BACKGROUND: Allele-specific methylation of the imprinting control region (ICR) is the molecular basis for the genomic imprinting phenomenon that is unique to placental mammals. We previously showed that the ICR at the mouse H19 gene locus (H19 ICR) was unexpectedly established after fertilization and not during spermatogenesis in transgenic mice (TgM), and that the same activity was essential for the maintenance of paternal methylation of the H19 ICR at the endogenous locus in pre-implantation embryos. To examine the universality of post-fertilization imprinted methylation across animal species or imprinted loci, we generated TgM with two additional sequences. RESULTS: The rat H19 ICR, which is very similar in structure to the mouse H19 ICR, unexpectedly did not acquire imprinted methylation even after fertilization, suggesting a lack of essential sequences in the transgene fragment. In contrast, the mouse IG-DMR, the methylation of which is acquired during spermatogenesis at the endogenous locus, did not acquire methylation in the sperm of TgM, yet became highly methylated in blastocysts after fertilization, but only when the transgene was paternally inherited. Since these two sequences were evaluated at the same genomic site by employing the transgene co-placement strategy, it is likely that the phenotype reflects the intrinsic activity of these fragments rather than position-effect variegation. CONCLUSIONS: Our results suggested that post-fertilization imprinted methylation is a versatile mechanism for protecting paternal imprinted methylation from reprogramming during the pre-implantation period.
Assuntos
Metilação de DNA , RNA Longo não Codificante , Animais , Feminino , Masculino , Camundongos , Gravidez , Ratos , Proteínas de Ligação ao Cálcio , Fertilização , Impressão Genômica , Peptídeos e Proteínas de Sinalização Intercelular , Proteínas de Membrana , Camundongos Transgênicos , Placenta , RNA Longo não Codificante/genética , SêmenRESUMO
Background: Notch signaling played a critical role in promoting breast tumorigenesis and progression. However, the role and prognostic value of Notch3 combined with DLL4 expression in breast carcinoma had not been explored. Methods: The retrospective study enrolled 90 breast cancer tissues and 60 noncancerous tissues from (conceal). The expression and prognostic value of Notch3 and DLL4 in patients with breast carcinoma were investigated using Oncomine and UALCAN database. Notch3 and DLL4 expression levels were detected by quantitative real-time polymerase chain reaction, western blotting, and immunohistochemistry. We analyzed the correlation between both proteins expression and clinicopathological parameters and survival data, respectively. Results: The expressions of Notch3 and DLL4 were increased, and Notch3 expression was significantly positively associated with DLL4 in breast carcinoma. The 2 proteins dramatically correlated with advanced stage, high grade and negative Her2 status. The overexpressing of single or both Notch3 and DLL4 resulted in shortened survival of breast cancer patients. And Notch3 overexpression was one of independent risk predictors to poor prognosis. Conclusion: The interaction of Notch3 receptor and DLL4 ligand accelerates oncogenesis, progression, and poor prognosis of breast cancer patients. Notch3 protein may serve as one of biomarker to independently predict prognosis of patients.
Assuntos
Proteínas Adaptadoras de Transdução de Sinal , Neoplasias da Mama , Proteínas de Ligação ao Cálcio , Receptor Notch3 , Feminino , Humanos , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Neoplasias da Mama/patologia , Proteínas de Ligação ao Cálcio/genética , Proteínas de Ligação ao Cálcio/metabolismo , Prognóstico , Receptor Notch3/genética , Receptor Notch3/metabolismo , Estudos Retrospectivos , Transdução de SinaisRESUMO
During Agrobacterium rhizogenes-plant interaction, the rolB gene is transferred into the plant genome and is stably inherited in the plant's offspring. Among the numerous effects of rolB on plant metabolism, including the activation of secondary metabolism, its effect on plant defense systems has not been sufficiently studied. In this work, we performed a proteomic analysis of rolB-expressing Arabidopsis thaliana plants with particular focus on defense proteins. We found a total of 77 overexpressed proteins and 64 underexpressed proteins in rolB-transformed plants using two-dimensional gel electrophoresis and MALDI mass spectrometry. In the rolB-transformed plants, we found a reduced amount of scaffold proteins RACK1A, RACK1B, and RACK1C, which are known as receptors for activated C-kinase 1. The proteomic analysis showed that rolB could suppress the plant immune system by suppressing the RNA-binding proteins GRP7, CP29B, and CP31B, which action are similar to the action of type-III bacterial effectors. At the same time, rolB plants induce the massive biosynthesis of protective proteins VSP1 and VSP2, as well as pathogenesis-related protein PR-4, which are markers of the activated jasmonate pathway. The increased contents of glutathione-S-transferases F6, F2, F10, U19, and DHAR1 and the osmotin-like defense protein OSM34 were found. The defense-associated protein PCaP1, which is required for oligogalacturonide-induced priming and immunity, was upregulated. Moreover, rolB-transformed plants showed the activation of all components of the PYK10 defense complex that is involved in the metabolism of glucosinolates. We hypothesized that various defense systems activated by rolB protect the host plant from competing phytopathogens and created an effective ecological niche for A. rhizogenes. A RolB â RACK1A signaling module was proposed that might exert most of the rolB-mediated effects on plant physiology. Our proteomics data are available via ProteomeXchange with identifier PXD037959.
Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Proteínas de Bactérias/metabolismo , Proteínas de Ligação ao Cálcio/metabolismo , Oncogenes , Plantas Geneticamente Modificadas/genética , ProteômicaRESUMO
Background: Mounting evidence have indicated that long noncoding RNA (lncRNA) muscleblind like splicing regulator 1 antisense RNA 1 (MBNL1-AS1) play a crucial regulatory role in cardiovascular disease, myocardial infarction (MI) included. In this research, we sought to probe into the biological function and potential mechanism of MBNL1-AS1 in MI. Methods: Cardiomyocytes were treated under hypoxic conditions for 0-12 h. Functional assays including CCK-8 and flow cytometry were performed to assess hypoxia-stimulated cardiomyocyte viability and apoptosis, respectively. Moreover, bioinformatics analysis and mechanical assays were conducted to reveal the competitive endogenous RNA (ceRNA) mechanism of MBNL1-AS1. Results: The upregulation of MBNL1-AS1 was found in hypoxia-stimulated cardiomyocytes. Functionally, the downregulation of MBNL1-AS1 dramatically promoted hypoxia-induced cardiomyocyte viability and inhibited apoptosis. Mechanistically, miR-132-3p bound to MBNL1-AS1 in hypoxia-induced cardiomyocytes, and miR-132-3p directly targeted RAB14, member RAS oncogene family (RAB14) and calmodulin binding transcription activator 1 (CAMTA1). Furthermore, MBNL1-AS1 upregulates the expression of RAB14 and CAMTA1 in hypoxia-stimulated cardiomyocytes via targeting miR-132-3p. Conclusions: The current study revealed the critical role of the MBNL1-AS1/miR-132-3p/RAB14/CAMTA1 axis in MI, indicating MBNL1-AS1 as an innovative therapeutic target for MI.
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MicroRNAs , Infarto do Miocárdio , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , RNA Antissenso/genética , RNA Antissenso/metabolismo , Apoptose/genética , Infarto do Miocárdio/genética , Infarto do Miocárdio/metabolismo , Hipóxia , Proliferação de Células/genética , Proteínas de Ligação ao Cálcio , Transativadores/metabolismo , Proteínas de Ligação a RNA/genética , Proteínas rab de Ligação ao GTP/metabolismoRESUMO
BACKGROUND: Neurodevelopmental disorders (NDDs) are a group of disorders induced by abnormal brain developmental processes. The prefrontal cortex (PFC) plays an essential role in executive function, and its role in NDDs has been reported. NDDs are associated with high-risk gene mutations and share partially overlapping genetic abnormalities. METHODS: Neurexins (NRXNs) are related to autism spectrum disorder (ASD) and attention-deficit hyperactivity disorder (ADHD). NRXN1, an essential susceptibility gene for NDDs, has been reported to be associated with NDDs. However, little is known about its key role in NDDs. RESULTS: NRXN1 downregulation in the medial PFC induced anxiety-like behaviors and abnormal social phenotypes with impaired neurite outgrowth in Sh-NRXN1 in prefrontal neurons. Moreover, tandem mass tag (TMT)-based proteomic analysis of rat brain samples showed that NRXN1 downregulation led to significant proteome alterations, including pathways related to the extracellular matrix, cell membrane, and morphologic change. Furthermore, full-automatic immunoblotting analysis verified the differently expressed proteins related to cell morphology and membrane structure. CONCLUSIONS: Our results confirmed the association of NRXN1 with abnormal behaviors in NDDs and provided richer insights into specific prefrontal knockdown in adolescence, potentially expanding the NRXN1 interactome and contributing to human health.
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Transtorno do Espectro Autista , Animais , Ratos , Ansiedade , Transtorno do Espectro Autista/genética , Proteínas de Ligação ao Cálcio/genética , Moléculas de Adesão de Célula Nervosa/genética , Crescimento Neuronal , Fenótipo , Córtex Pré-Frontal , ProteômicaRESUMO
Surface levels of membrane proteins are determined by a dynamic balance between exocytosis-mediated surface delivery and endocytosis-dependent retrieval from the cell surface. Imbalances in surface protein levels perturb surface protein homeostasis and cause major forms of human disease such as type 2 diabetes and neurological disorders. Here, we found a Reps1-Ralbp1-RalA module in the exocytic pathway broadly regulating surface protein levels. Reps1 and Ralbp1 form a binary complex that recognizes RalA, a vesicle-bound small guanosine triphosphatases (GTPase) promoting exocytosis through interacting with the exocyst complex. RalA binding results in Reps1 release and formation of a Ralbp1-RalA binary complex. Ralbp1 selectively recognizes GTP-bound RalA but is not a RalA effector. Instead, Ralbp1 binding maintains RalA in an active GTP-bound state. These studies uncovered a segment in the exocytic pathway and, more broadly, revealed a previously unrecognized regulatory mechanism for small GTPases, GTP state stabilization.
Assuntos
Diabetes Mellitus Tipo 2 , Humanos , GTP Fosfo-Hidrolases/metabolismo , Proteínas de Membrana/metabolismo , Exocitose , Guanosina Trifosfato/metabolismo , Proteínas de Ligação ao Cálcio , Transportadores de Cassetes de Ligação de ATP , Proteínas Ativadoras de GTPase/metabolismo , Proteínas ral de Ligação ao GTP/metabolismoRESUMO
Phospholamban (PLN) is a major regulator of cardiac contractility, and human mutations in this gene give rise to inherited cardiomyopathies. The deletion of Arginine 14 is the most-prevalent cardiomyopathy-related mutation, and it has been linked to arrhythmogenesis and early death. Studies in PLN-humanized mutant mice indicated an increased propensity to arrhythmias, but the underlying cellular mechanisms associated with R14del-PLN cardiac dysfunction in the absence of any apparent structural remodeling remain unclear. The present study addressed the specific role of myofilaments in the setting of R14del-PLN and the long-term effects of R14del-PLN in the heart. Maximal force was depressed in skinned cardiomyocytes from both left and right ventricles, but this effect was more pronounced in the right ventricle of R14del-PLN mice. In addition, the Ca2+ sensitivity of myofilaments was increased in both ventricles of mutant mice. However, the depressive effects of R14del-PLN on contractile parameters could be reversed with the positive inotropic drug omecamtiv mecarbil, a myosin activator. At 12 months of age, corresponding to the mean symptomatic age of R14del-PLN patients, contractile parameters and Ca2+ transients were significantly depressed in the right ventricular R14del-PLN cardiomyocytes. Echocardiography did not reveal any alterations in cardiac function or remodeling, although histological and electron microscopy analyses indicated subtle alterations in mutant hearts. These findings suggest that both aberrant myocyte calcium cycling and aberrant contractility remain specific to the right ventricle in the long term. In addition, altered myofilament activity is an early characteristic of R14del-PLN mutant hearts and the positive inotropic drug omecamtiv mecarbil may be beneficial in treating R14del-PLN cardiomyopathy.
Assuntos
Cardiomiopatias , Miofibrilas , Humanos , Camundongos , Animais , Miofibrilas/metabolismo , Cardiomiopatias/genética , Cardiomiopatias/terapia , Proteínas de Ligação ao Cálcio/genética , Arritmias Cardíacas/genética , Cálcio/metabolismoRESUMO
Mitochondrial calcium (m Ca2+ ) uptake occurs via the Mitochondrial Ca2+ Uniporter (MCU) complex and plays a critical role in mitochondrial dynamics, mitophagy, and apoptosis. MCU complex activity is in part modulated by the expression of its regulatory subunits. Cardiovascular disease models demonstrated altered gene/protein expression of one or multiple subunits in different cells, including vascular endothelial cells (ECs). MCU complex activity was found necessary for stable flow (s-flow)-induced mitophagy and promotion of an atheroprotective EC phenotype. Disturbed flow (d-flow) is known to lead to an atheroprone phenotype. Despite the role of MCU in flow-regulated EC function, flow-induced alterations in MCU complex subunit expression are currently unknown. We exposed cultured human ECs to atheroprotective (steady shear stress, SS) or atheroprone flow (oscillatory shear stress, OS) and measured mRNA and protein levels of the MCU complex members. SS and OS differentially modulated subunit expression at gene/protein levels. Protein expression changes of the core MCU, m Ca2+ uptake 1 (MICU1) and MCU regulator 1 (MCUR1) subunits in SS- and OS-exposed, compared to static, ECs suggested an enhanced m Ca2+ influx under each flow and a potential contribution to EC dysfunction under OS. In silico analysis of a single-cell RNA-sequencing dataset was employed to extract transcript values of MCU subunits in mouse carotid ECs from regions exposed to s-flow or d-flow. Mcu and Mcur1 genes showed significant differences in expression after prolonged exposure to each flow. The differential expression of MCU complex subunits indicated a tight regulation of the complex activity under physiological and pathological hemodynamic conditions.
Assuntos
Células Endoteliais , Proteínas de Transporte da Membrana Mitocondrial , Camundongos , Humanos , Animais , Células Endoteliais/metabolismo , Proteínas de Transporte da Membrana Mitocondrial/genética , Canais de Cálcio/genética , Canais de Cálcio/metabolismo , Mitocôndrias/metabolismo , Coração , Cálcio/metabolismo , Proteínas de Ligação ao Cálcio/metabolismoRESUMO
The rate of calcium cycling and calcium transient amplitude are critical determinants for the efficient contraction and relaxation of the heart. Calcium-handling proteins in the cardiac myocyte are altered in heart failure, and restoring the proper function of those proteins is an effective potential therapeutic strategy. The calcium-handling proteins or their regulators are phosphorylated by a cAMP-dependent kinase (PKA), and thereby their activity is regulated. A-Kinase Anchoring Proteins (AKAPs) play a seminal role in orchestrating PKA and cAMP regulators in calcium handling and contractile machinery. This cAMP/PKA orchestration is crucial for the increased force and rate of contraction and relaxation of the heart in response to fight-or-flight. Knockout models and the few available preclinical models proved that the efficient targeting of AKAPs offers potential therapies tailor-made for improving defective calcium cycling. In this review, we highlight important studies that identified AKAPs and their regulatory roles in cardiac myocyte calcium cycling in health and disease.
Assuntos
Proteínas de Ancoragem à Quinase A , Cálcio , Insuficiência Cardíaca , Miócitos Cardíacos , Humanos , Proteínas de Ancoragem à Quinase A/metabolismo , Cálcio/metabolismo , Proteínas de Ligação ao Cálcio/metabolismo , Insuficiência Cardíaca/metabolismo , Miócitos Cardíacos/metabolismoRESUMO
The extracellular matrix (ECM), as an important component of the tumor microenvironment, exerts various roles in tumor formation. Mitochondrial dynamic disorder is closely implicated in tumorigenesis, including hyperfission in HCC. We aimed to determine the influence of the ECM-related protein CCBE1 on mitochondrial dynamics in HCC. Here, we found that CCBE1 was capable of promoting mitochondrial fusion in HCC. Initially, CCBE1 expression was found to be significantly downregulated in tumors compared with nontumor tissues, which resulted from hypermethylation of the CCBE1 promoter in HCC. Furthermore, CCBE1 overexpression or treatment with recombinant CCBE1 protein dramatically inhibited HCC cell proliferation, migration, and invasion in vitro and in vivo. Mechanistically, CCBE1 functioned as an inhibitor of mitochondrial fission by preventing the location of DRP1 on mitochondria through inhibiting its phosphorylation at Ser616 by directly binding with TGFßR2 to inhibit TGFß signaling activity. In addition, a higher percentage of specimens with higher DRP1 phosphorylation was present in patients with lower CCBE1 expression than in patients with higher CCBE1 expression, which further confirmed the inhibitory effect of CCBE1 on DRP1 phosphorylation at Ser616. Collectively, our study highlights the crucial roles of CCBE1 in mitochondrial homeostasis, suggesting strong evidence for this process as a potential therapeutic strategy for HCC.
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Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Dinâmica Mitocondrial , Neoplasias Hepáticas/metabolismo , Mitocôndrias/genética , Mitocôndrias/metabolismo , Proliferação de Células , Microambiente Tumoral , Proteínas de Ligação ao Cálcio/metabolismo , Proteínas Supressoras de TumorRESUMO
Notch ligands present during interactions between T cells and dendritic cells (DCs) dictate cell phenotype through a myriad of effects including the induction of T cell regulation, survival, and cytokine response. The presence of Notch ligands on DCs varies with the context of the inflammatory response; Jagged-1 is constitutively expressed, whereas Delta-like 1 and Delta-like 4 are induced in response to pathogen exposure. Although Delta-like and Jagged ligands send different signals through the same Notch receptor, the role of these two ligands in peripheral T cell immunity is not clear. The goal of our studies was to determine the role of Jagged-1 in the pathogen-free inflammation induced by OVA during allergic airway disease in mice. Our studies show that a deletion in DC-expressed Jagged-1 causes a significant increase in cytokine production, resulting in increased mucus production and increased eosinophilia in the lungs of mice sensitized and challenged with OVA. We also observed that a reduction of Jagged-1 expression is correlated with increased expression of the Notch 1 receptor on the surface of CD4+ T cells in both the lung and lymph node. Through transfer studies using OT-II transgenic T cells, we demonstrate that Jagged-1 represses the expansion of CD44+CD62L+CCR7+ memory cells and promotes the expansion of CD44+CD62L- effector cells, but it has no effect on the expansion of naive cells during allergic airway disease. These data suggest that Jagged-1 may have different roles in Ag-specific T cell responses, depending on the maturity of the stimulated T cell.
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Hipersensibilidade , Células Th2 , Camundongos , Animais , Proteína Jagged-1/genética , Proteína Jagged-1/metabolismo , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Proteínas de Ligação ao Cálcio/genética , Proteínas de Ligação ao Cálcio/metabolismo , Citocinas/metabolismo , Inflamação/metabolismoRESUMO
Sensor-responder complexes comprising calcineurin B-like (CBL) proteins and CBL-interacting protein kinases (CIPKs) are plant-specific Ca2+ receptors, and the CBL-CIPK module is widely involved in plant growth and development and a large number of abiotic stress response signaling pathways. In this study, the potato cv. "Atlantic" was subjected to a water deficiency treatment and the expression of StCIPK18 gene was detected by qRT-PCR. The subcellular localization of StCIPK18 protein was observed by a confocal laser scanning microscope. The StCIPK18 interacting protein was identified and verified by yeast two-hybrid (Y2H) and bimolecular fluorescence complementation (BiFC). StCIPK18 overexpression and StCIPK18 knockout plants were constructed. The phenotypic changes under drought stress were indicated by water loss rate, relative water content, MDA and proline contents, and CAT, SOD and POD activities. The results showed that StCIPK18 expression was upregulated under drought stress. StCIPK18 is localized in the cell membrane and cytoplasm. Y2H shows the interaction between StCIPK18 and StCBL1, StCBL4, StCBL6 and StCBL8. BiFC further verifies the reliability of the interaction between StCIPK18 and StCBL4. Under drought stress, StCIPK18 overexpression decreased the water loss rate and MDA, and increased RWC, proline contents and CAT, SOD and POD activities; however, StCIPK18 knockout showed opposite results, compared with the wild type, in response to drought stress. The results can provide information for the molecular mechanism of the StCIPK18 regulating potato response to drought stress.
Assuntos
Arabidopsis , Solanum tuberosum , Solanum tuberosum/metabolismo , Resistência à Seca , Proteínas de Plantas/genética , Arabidopsis/genética , Reprodutibilidade dos Testes , Proteínas de Ligação ao Cálcio/metabolismo , Proteínas Quinases/metabolismo , Secas , Água/metabolismo , Superóxido Dismutase/metabolismo , Estresse Fisiológico , Regulação da Expressão Gênica de PlantasRESUMO
INTRODUCTION: Mouse skeletal stem cells (mSSCs, CD45-Ter119-Tie2-CD51+Thy-6C3-CD105-CD200+population) are identified in growth plates (GP) and play important roles in bone regeneration. However, the role of mSSCs in osteoporosis remains unclear. MATERIALS AND METHODS: The GP were stained by HE staining, and the mSSC lineage was analyzed by flow cytometry at postnatal of 14 days and 30 days in wild-type mice. The mice (8 weeks) were either sham operated or ovariectomy (OVX) and then sacrificed at 2, 4 and 8 w. The GP were stained by Movat staining, and mSSC lineage was analyzed. Then, mSSCs were sorted by fluorescence-activated cell sorting (FACS); the clonal ability, chondrogenic differentiation and osteogenic differentiation were evaluated, and the changed genes were analyzed by RNA-seq. RESULTS: The percentage of mSSCs were decreased with the narrow GP. Heights of GP were decreased significantly in 8w-ovx mice compared with 8w-sham mice. We found the percentage of mSSCs were decreased in mice at 2w after ovx, but the cell numbers were not changed. Further, the percentage and cell numbers of mSSCs were not changed at 4w and 8w after ovx. Importantly, the clonal ability, chondrogenic differentiation and osteogenic differentiation of mSSCs were impaired at 8w after ovx. We found 114 genes were down-regulated in mSSCs, including skeletal developmental genes such as Col10a1, Col2a1, Mef2c, Sparc, Matn1, Scube2 and Dlx5. On the contrary, 526 genes were up-regulated, including pro-inflammatory genes such as Csf1, Nfkbla, Nfatc2, Nfkb1 and Nfkb2. CONCLUSION: Function of mSSCs was impaired by up-regulating pro-inflammatory genes in ovx-induced osteoporosis.
Assuntos
Osteogênese , Osteoporose , Humanos , Feminino , Camundongos , Animais , Osteogênese/genética , Lâmina de Crescimento , Células-Tronco , Diferenciação Celular , Ovariectomia , Proteínas de Ligação ao Cálcio , Proteínas Adaptadoras de Transdução de SinalRESUMO
An increasing number of studies have found that long non-coding RNA (lncRNA) play important roles in driving the progression of nasopharyngeal carcinoma (NPC). Our microarray screening revealed that expression of the lncRNA long intergenic non-protein coding RNA 173 (LINC00173) was upregulated in NPC. However, its role and mechanism in NPC have not yet been elucidated. In this study, we demonstrate that high LINC00173 expression indicated a poor prognosis in NPC patients. Knockdown of LINC00173 significantly inhibited NPC cell proliferation, migration and invasion in vitro. Mechanistically, LINC00173 interacted and colocalized with Ras-related protein Rab-1B (RAB1B) in the cytoplasm, but the modulation of LINC00173 expression did not affect the expression of RAB1B at either the mRNA or protein levels. Instead, relying on the stimulation of RAB1B, LINC00173 could facilitate the extracellular secretion of proliferation-associated 2G4 (PA2G4) and stromal cell-derived factor 4 (SDF4; also known as 45-kDa calcium-binding protein) proteins, and knockdown of these proteins could reverse the NPC aggressive phenotype induced by LINC00173 overexpression. Moreover, in vivo LINC00173-knockdown models exhibited a marked slowdown in tumor growth and a significant reduction in lymph node and lung metastases. In summary, LINC00173 serves as a crucial driver for NPC progression, and the LINC00173-RAB1B-PA2G4/SDF4 axis might provide a potential therapeutic target for NPC patients.