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Cancer cells evade T cell-mediated killing through tumour-immune interactions whose mechanisms are not well understood1,2. Dendritic cells (DCs), especially type-1 conventional DCs (cDC1s), mediate T cell priming and therapeutic efficacy against tumours3. DC functions are orchestrated by pattern recognition receptors3-5, although other signals involved remain incompletely defined. Nutrients are emerging mediators of adaptive immunity6-8, but whether nutrients affect DC function or communication between innate and adaptive immune cells is largely unresolved. Here we establish glutamine as an intercellular metabolic checkpoint that dictates tumour-cDC1 crosstalk and licenses cDC1 function in activating cytotoxic T cells. Intratumoral glutamine supplementation inhibits tumour growth by augmenting cDC1-mediated CD8+ T cell immunity, and overcomes therapeutic resistance to checkpoint blockade and T cell-mediated immunotherapies. Mechanistically, tumour cells and cDC1s compete for glutamine uptake via the transporter SLC38A2 to tune anti-tumour immunity. Nutrient screening and integrative analyses show that glutamine is the dominant amino acid in promoting cDC1 function. Further, glutamine signalling via FLCN impinges on TFEB function. Loss of FLCN in DCs selectively impairs cDC1 function in vivo in a TFEB-dependent manner and phenocopies SLC38A2 deficiency by eliminating the anti-tumour therapeutic effect of glutamine supplementation. Our findings establish glutamine-mediated intercellular metabolic crosstalk between tumour cells and cDC1s that underpins tumour immune evasion, and reveal glutamine acquisition and signalling in cDC1s as limiting events for DC activation and putative targets for cancer treatment.
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Sistema A de Transporte de Aminoácidos , Células Dendríticas , Glutamina , Neoplasias , Transdução de Sinais , Sistema A de Transporte de Aminoácidos/metabolismo , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/metabolismo , Linfócitos T CD8-Positivos/imunologia , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Glutamina/metabolismo , Neoplasias/imunologia , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Supressoras de Tumor/metabolismoRESUMO
Dendritic cells (DCs) are innate immune cells that detect and process environmental signals and communicate them with T cells to bridge innate and adaptive immunity. Immune signals and microenvironmental cues shape the function of DC subsets in different contexts, which is associated with reprogramming of cellular metabolic pathways. In addition to integrating these extracellular cues to meet bioenergetic and biosynthetic demands, cellular metabolism interplays with immune signaling to shape DC-dependent immune responses. Emerging evidence indicates that lipid metabolism serves as a key regulator of DC responses. Here, we summarize the roles of fatty acid and cholesterol metabolism, as well as selective metabolites, in orchestrating the functions of DCs. Specifically, we highlight how different lipid metabolic programs, including de novo fatty acid synthesis, fatty acid ß oxidation, lipid storage, and cholesterol efflux, influence DC function in different contexts. Further, we discuss how dysregulation of lipid metabolism shapes DC intracellular signaling and contributes to the impaired DC function in the tumor microenvironment. Finally, we conclude with a discussion on key future directions for the regulation of DC biology by lipid metabolism. Insights into the connections between lipid metabolism and DC functional specialization may facilitate the development of new therapeutic strategies for human diseases.
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Células Dendríticas , Metabolismo dos Lipídeos , Humanos , Ácidos Graxos/metabolismo , Colesterol/metabolismo , BiologiaRESUMO
mTORC1, the major homeostatic sensor and responder, regulates cell catabolism mainly by targeting autophagy. Here, we show that mTORC1 directly controls autophagosome formation via phosphorylation of WIPI2, a critical protein in isolation membrane growth and elongation. mTORC1 phosphorylates Ser395 of WIPI2, directing WIPI2 to interact specifically with the E3 ubiquitin ligase HUWE1 for ubiquitination and proteasomal degradation. Physiological or pharmacological inhibition of mTORC1 in cells promotes WIPI2 stabilization, autophagosome formation, and autophagic degradation. In mouse liver, fasting significantly increases the WIPI2 protein level, while silencing HUWE1 enhances autophagy, and introducing WIPI2 improves lipid clearance. Thus, regulation of the intracellular WIPI2 protein level by mTORC1 and HUWE1 is a key determinant of autophagy flux and may coordinate the initiation, progression, and completion of autophagy.
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Autofagia/fisiologia , Proteínas de Transporte/metabolismo , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Proteínas de Membrana/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Animais , Células HEK293 , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Proteínas de Ligação a Fosfato , Ubiquitinação/fisiologiaRESUMO
Acetylation is increasingly recognized as one of the major post-translational mechanisms for the regulation of multiple cellular functions in mammalian cells. Acetyltransferase p300, which acetylates histone and non-histone proteins, has been intensively studied in its role in cell growth and metabolism. However, the mechanism underlying the activation of p300 in cells remains largely unknown. Here, we identify the homeostatic sensor mTORC1 as a direct activator of p300. Activated mTORC1 interacts with p300 and phosphorylates p300 at 4 serine residues in the C-terminal domain. Mechanistically, phosphorylation of p300 by mTORC1 prevents the catalytic HAT domain from binding to the RING domain, thereby eliminating intra-molecular inhibition. Functionally, mTORC1-dependent phosphorylation of p300 suppresses cell-starvation-induced autophagy and activates cell lipogenesis. These results uncover p300 as a direct target of mTORC1 and suggest that the mTORC1-p300 pathway plays a pivotal role in cell metabolism by coordinately controlling cell anabolism and catabolism.
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Autofagia , Lipogênese , Complexos Multiproteicos/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Fatores de Transcrição de p300-CBP/metabolismo , Animais , Células HEK293 , Células HeLa , Células Hep G2 , Humanos , Alvo Mecanístico do Complexo 1 de Rapamicina , Camundongos , Complexos Multiproteicos/genética , Fosforilação/genética , Domínios Proteicos , Serina-Treonina Quinases TOR/genética , Fatores de Transcrição de p300-CBP/genéticaRESUMO
OBJECTIVE: To investigate the effectiveness of high-frequency repetitive transcranial magnetic stimulation (HF-rTMS) on improvement of clinical symptoms in patients with spinocerebellar ataxia type 3 (SCA3). METHODS: Sixteen SCA3 participants diagnosed by genetic testing were enrolled in this sham-controlled and double-blind trial. They received either a 2-week 10-Hz rTMS intervention or sham stimulation targeting the vermis and cerebellum. The Scale for Assessment and Rating of Ataxia and the International Cooperative Ataxia Rating Scale were completed at baseline and poststimulation. RESULTS: Compared with baseline, the HF-rTMS group demonstrated a significant improvement in the total Scale for Assessment and Rating of Ataxia ( P < 0.0001) and the International Cooperative Ataxia Rating Scale scores ( P = 0.002). After 2-week treatment, the real group exhibited decreasing pattern in 3 subgroups, especially for limb kinetic function ( P < 0.0001). CONCLUSIONS: Short-term HF-rTMS treatment is a potentially promising and feasible tool for rehabilitation in patients with SCA3. Studies with long-term follow-up need to be carried out in the future and further need to assess gait, limb kinetic function, speech and oculomotor disorders.
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Eletroconvulsoterapia , Doença de Machado-Joseph , Humanos , Estimulação Magnética Transcraniana , Doença de Machado-Joseph/terapia , Ataxia/terapia , Cerebelo , Método Duplo-Cego , Resultado do TratamentoRESUMO
Shuttling of macromolecules between different cellular compartments helps regulate the timing and extent of different cellular activities. Here, we report that LC3, a key initiator of autophagy that cycles between the nucleus and cytoplasm, becomes selectively activated in the nucleus during starvation through deacetylation by the nuclear deacetylase Sirt1. Deacetylation of LC3 at K49 and K51 by Sirt1 allows LC3 to interact with the nuclear protein DOR and return to the cytoplasm with DOR, where it is able to bind Atg7 and other autophagy factors and undergo phosphatidylethanolamine conjugation to preautophagic membranes. The association of deacetylated LC3 with autophagic factors shifts LC3's distribution from the nucleus toward the cytoplasm. Thus, an acetylation-deacetylation cycle ensures that LC3 effectively redistributes in an activated form from nucleus to cytoplasm, where it plays a central role in autophagy to enable the cell to cope with the lack of external nutrients.
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Autofagia , Núcleo Celular/metabolismo , Lisina/metabolismo , Proteínas Associadas aos Microtúbulos/metabolismo , Sirtuína 1/metabolismo , Acetilação , Proteína 7 Relacionada à Autofagia , Citoplasma/metabolismo , Células HEK293 , Células HeLa , Humanos , Microscopia Confocal , Proteínas Associadas aos Microtúbulos/genética , Proteínas Associadas aos Microtúbulos/ultraestrutura , Enzimas Ativadoras de Ubiquitina/metabolismoRESUMO
Accumulating evidence highlights the role of histone acetyltransferase GCN5 in the regulation of cell metabolism in metazoans. Here, we report that GCN5 is a negative regulator of autophagy, a lysosome-dependent catabolic mechanism. In animal cells and Drosophila, GCN5 inhibits the biogenesis of autophagosomes and lysosomes by targeting TFEB, the master transcription factor for autophagy- and lysosome-related gene expression. We show that GCN5 is a specific TFEB acetyltransferase, and acetylation by GCN5 results in the decrease in TFEB transcriptional activity. Induction of autophagy inactivates GCN5, accompanied by reduced TFEB acetylation and increased lysosome formation. We further demonstrate that acetylation at K274 and K279 disrupts the dimerization of TFEB and the binding of TFEB to its target gene promoters. In a Tau-based neurodegenerative Drosophila model, deletion of dGcn5 improves the clearance of Tau protein aggregates and ameliorates the neurodegenerative phenotypes. Together, our results reveal GCN5 as a novel conserved TFEB regulator, and the regulatory mechanisms may be involved in autophagy- and lysosome-related physiological and pathological processes.
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Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos , Proteínas de Drosophila/metabolismo , Histona Acetiltransferases/metabolismo , Lisossomos , Acetilação , Animais , Autofagossomos/metabolismo , Autofagia/genética , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/genética , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/metabolismo , Drosophila , Lisossomos/metabolismoRESUMO
Based on low-rank matrix reconstruction theory, this paper proposes a joint DOD and DOA estimation method for coherent targets with bistatic coprime array MIMO radar. Unlike the conventional vectorization, the proposed method processed the coprime array with virtual sensor interpolation, which obtained a uniform linear array to generate the covariance matrix. Then, we reconstructed the Toeplitz matrix and established a matrix optimization recovery model according to the kernel norm minimization theory. Finally, the reduced dimension multiple signal classification algorithm was applied to estimate the angle of the coherent targets, with which the automatic pairing of DOD and DOA could be realized. With the same number of physical sensors, the proposed method expanded the array aperture effectively, so that the degree of freedom and angular resolution could be improved significantly for coherent signals. However, the effectiveness of the method was largely limited by the signal-to-noise ratio. The superiority and effectiveness of the method were proved using simulation experiments.
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Background: Cuproptosis is a recently discovered form of nonapoptotic programmed cell death. However, no research on cuproptosis in the context of adrenocortical carcinoma has been conducted, and the prognostic value of assessing cuproptosis remains unclear. Methods: In this study, we established comprehensive models to assess gene expression changes, mutation status, and prognosis prediction and developed a prognostic nomogram for cuproptosis-related genes. Using data from The Cancer Genome Atlas (TCGA), Gene Expression Omnibus (GEO), and Genotype-Tissue Expression (GTEx) databases, an analysis of 11 cuproptosis-related genes was performed. Additionally, a risk scoring method and nomogram were used to assess the relationships among cuproptosis-associated genes, transcript expression, clinical characteristics, and prognosis. The connections among tumors, immune checkpoints, and immune infiltration were also analyzed. Results: The patterns observed in patients with adrenocortical carcinoma who were assessed using cuproptosis-associated risk scores provide useful information for understanding gene mutations, clinical outcomes, immune cell infiltration, and immune checkpoint analysis results. FDX1, LIPT1, MTF1, COX11, CYP2D6, DLAT, ATP7Band CDKN2A were differentially expressed in patients with adrenocortical carcinoma and normal controls. In addition, higher risk scores were significantly associated with poor overall survival and progression-free interval. The nomogram model subsequently developed to facilitate the clinical application of the analysis showed good predictive and calibration capabilities. GSE10927 and GSE33371 were used for independent cohort validation. Moreover, CDKN2A, FDX1, and other cuproptosis-related genes were significantly associated with immune infiltration and checkpoints. Conclusion: We confirmed that our model had excellent predictive ability in patients with adrenocortical carcinoma. Therefore, an in-depth evaluation of patients using cuproptosis-related risk scores is clinically essential and can assist in therapy in the future.
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The changes in tongue coating metabolites in patients with chronic gastritis (CG) under different gastroscopy indicators were analyzed, and these metabolites were screened for potential non-invasive biomarkers to assist in the diagnosis of chronic gastritis. The technology of gas chromatography and liquid chromatography combined with mass spectrometry has been used to more comprehensively detect tongue coating metabolites of 350 CG patients. Spearman correlation analysis and random forest algorithm were used to screen metabolites that can serve as potential biomarkers. Compared with healthy individuals, CG group showed significant changes in the content of 101 metabolites, with an increase in the content of 54 metabolites and a decrease in the content of 47 metabolites. These differential metabolites are mainly composed of 47 lipids and lipid like substances. 1 metabolite was associated with bile reflux, 1 metabolite was associated with gastric mucosal erosion, 10 metabolites were associated with atrophy, 10 metabolites were associated with intestinal metaplasia, and 3 metabolites were associated with Helicobacter pylori infection. The ROC model composed of 5 metabolites can distinguish between CG group and healthy individuals, with an accuracy of 95.4%. The ROC model composed of 5,6-Dihydroxyindole can distinguish between chronic superficial gastritis group and chronic atrophic gastritis group, with an accuracy of 75.3%. The lipids and lipid like metabolites were the main abnormal metabolites in patients with chronic gastritis. It was worth noting that the content of Sphinganine 1-phase, 4-Ipomenol, and Nervonic acid in tongue coating increased, and the content of 1-Methyladenosine and 3-Hydroxycapric acid decreased, which helped to identify CG patients. The decrease in the content of 5,6-dihydroxyindole reminded patients that the development trend of CG was shifting from superficial to atrophic or even intestinal metaplasia. The detection of these metabolic markers of tongue coating was expected to be developed as a non-invasive and convenient technology in the future to assist us in monitoring and diagnosing the occurrence and development of CG.
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Biomarcadores , Gastrite , Lipídeos , Língua , Humanos , Gastrite/metabolismo , Gastrite/diagnóstico , Gastrite/microbiologia , Biomarcadores/metabolismo , Biomarcadores/análise , Masculino , Feminino , Língua/metabolismo , Língua/patologia , Pessoa de Meia-Idade , Adulto , Lipídeos/análise , Doença Crônica , Idoso , Infecções por Helicobacter/metabolismo , Infecções por Helicobacter/diagnósticoRESUMO
Small-interfering RNAs (siRNAs) offer promising prospects for treating pyroptosis-related autoimmune diseases. However, poor stability and off-target effects during in vivo transportation hinder their practical clinical applications. Precision delivery and adaptive release of siRNAs into inflamed tissues and immune cells could unleash their full therapeutic potential. This study establishes a pyroptotic-spatiotemporally selective siRNA delivery system (PMRC@siGSDME) that selectively targets inflammatory tissues, responds to pyroptosis, and exhibits remarkable therapeutic efficacy against various autoimmune diseases. Novel hybrid nanovesicles (NVs) are designed as a combination of pyroptotic macrophage membranes (PMs) and R8-cardiolipin-containing nanovesicles (RC-NVs). Evidence provides that PM-derived proteins involved in cell-cell interactions and membrane trafficking may contribute to the specificity of NVs to inflammatory tissue. In addition, cardiolipin anchored in the hybrid NVs increases its affinity for activated gasdermin E (GSDME) and achieves pyroptosis-adaptive release of siGSDME for the spatiotemporally selective suppression of immune responses. More importantly, PMRC@siGSDME displays significant anti-inflammatory and therapeutic effects in multiple mouse autoimmune disease models, including arthritis and inflammatory bowel disease (IBD). Collectively, an innovative siRNA delivery strategy precisely tailored for pyroptotic cells has been developed, paving the way for new treatments for autoimmune inflammatory diseases with minimal side effects and wide clinical applicability.
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Clarifying the distribution pattern and overlapping relationship of sympatric relative species in the spatio-temporal niche is important for our understanding of the behavioral relationship between species and the integrated management of multi-species habitats. Based on the infrared camera monitoring data from 2012 to 2021, we investigted the spatio-temporal distribution characteristics of the national secondary-class key protected animals Naemorhedus griseus and Capricornis milneedwardsii in the Gongga Mountain National Nature Reserve, Sichuan Province. We analyzed the distribution of N. griseuss and C. milneedwardsiis in the reserve using the MaxEnt model, based on 72 and 108 occurrence data of the two species, respectively, obtained by infrared cameras from 2016 to 2021, combined with 12 environmental factors potentially affecting their spatial distribution. Then, based on 1312 occurrence data of N. griseus and 1889 occurrence data of C. milneedwardsii collected by infrared camera from 2012 to 2021, we estimated their daily activity rhythms by using the kernel density estimation to understand the distribution pattern and overlap of the two species in the temporal niche. The results showed that the area of suitable habitats for N. griseus and C. milneedwardsii was 731.95 km2 and 1220.46 km2, respectively. The overlapping area was 697.17 km2. The main environmental factors had similar effects on the habitat selection of the two species. The daily activity of both species peaked in the early morning and evening. The utilization of the interval and intensity of the morning and evening time periods were different for the two species. The morning and evening activity peaks of C. milneedwardsii were earlier and later, respectively, than that of N. griseus. C. milneedwardsii had a higher utilization intensity during the nocturnal period. In general, high degree of spatial overlap and low degree of overlap in the temporal niche dimension contribute to the long-term coexistence of the two species.
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Análise Espacial , Animais , ChinaRESUMO
Anomaly detection is an active research field in industrial defect detection and medical disease detection. However, previous anomaly detection works suffer from unstable training, or non-universal criteria of evaluating feature distribution. In this paper, we introduce UTRAD, a U-TRansformer based Anomaly Detection framework. Deep pre-trained features are regarded as dispersed word tokens, and represented with transformer-based autoencoders. With reconstruction on more informative feature distribution instead of raw images, we achieve a more stable training process and a more precise anomaly detection and localization result. In addition, our proposed UTRAD has a multi-scale pyramidal hierarchy with skip connections that help detect both multi-scale structural and non-structural anomalies. As attention layers are decomposed to multi-level patches, UTRAD significantly reduces the computational cost and memory usage compared with the vanilla transformer. Experiments on industrial dataset MVtec AD and medical datasets Retinal-OCT, Brain-MRI, Head-CT have been conducted. Our proposed UTRAD out-performs all other state-of-the-art methods in the above datasets. Code released at https://github.com/gordon-chenmo/UTRAD.
Assuntos
Imageamento por Ressonância Magnética , Neuroimagem , Tomografia Computadorizada por Raios XRESUMO
Clarifying the distribution pattern and overlapping relationship of sympatric relative species in the spatio-temporal niche is of great significance to the basic theory of community ecology and integrated management of multi-species habitats in the same landscape. In this study, based on a 9-year dataset (2012-2021) from 493 camera-trap sites in the Gongga Mountain National Nature Reserve, we analyzed the habitat distributions and activity patterns of tufted deer (Elaphodus cephalophus) and sambar (Rusa unicolor). (1) Combined with 235 and 153 valid presence sites of tufted deer and sambar, the MaxEnt model was used to analyze the distribution of the two species based on 11 ecological factors. The distribution areas of the two species were 1038.40 km2 and 692.67 km2, respectively, with an overlapping area of 656.67 km2. Additionally, the overlap indexes Schoener's D (D) and Hellinger's-based I (I) were 0.703 and 0.930, respectively. (2) Based on 10,437 and 5203 independent captures of tufted deer and sambar, their daily activity rhythms were calculated by using the kernel density estimation. The results showed that the daily activity peak in the two species appeared at dawn and dusk; however, the activity peak in tufted deer at dawn and dusk was later and earlier than sambar, respectively. Our findings revealed the spatio-temporal niche relationship between tufted deer and sambar, contributing to a further understanding of the coexistence mechanism and providing scientific information for effective wild animal conservation in the reserve and other areas in the southeastern edge of the Qinghai-Tibetan Plateau.
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TP53INP2/DOR (tumor protein p53-inducible nuclear protein 2) contributes to mammalian macroautophagy/autophagy by carrying nuclear deacetylated MAP1LC3/LC3 to the cytoplasm. Here, we report that in the cytoplasm, TP53INP2 further functions in autophagosome biogenesis by promoting LC3B-ATG7 interaction. Cytoplasmic expression of the N-terminal region of TP53INP2, which includes the LC3-interacting region, effectively triggered LC3B-PE production and autophagosome formation. In the cytoplasm, TP53INP2 colocalized to early autophagic membrane structures containing ATG14, ZFYVE1/DFCP1 or WIPI2. While knockdown of TP53INP2 did not affect the formation of these autophagic structures, deletion of BECN1 or Atg5, or mutations preventing TP53INP2 from LC3 interaction, disrupted the membrane binding of TP53INP2. TP53INP2 interacted directly with ATG7 to form a LC3B-TP53INP2-ATG7 complex in the cytoplasm. Loss of TP53INP2-LC3 or TP53INP2-ATG7 interaction significantly reduced LC3B-ATG7 binding. Together, these results suggest that after shifting from the nucleus, cytoplasmic TP53INP2 is targeted to early autophagic membranes accompanied by LC3, where it contributes to autophagosome biogenesis by mediating LC3-ATG7 interaction. Abbreviations: 3-MA, 3-methyladenine; 3NES, 3 repeated nuclear export signal; 3NLS, 3 repeated nuclear localization signal; ACTB, actin beta; ATG, autophagy related; BECN1, Beclin 1; mCherry, monomeric red fluorescent protein mCherry; GFP, green fluorescent protein; GST, glutathione S-transferase; KO, knockout; LC3B/MAP1LC3B, microtubule-associated protein 1 light chain 3 beta; LC3B[G120], LC3B mutant lacking amino acids after glycine 120; LDH, lactate dehydrogenase; LMNB1, lamin B1; LIR, LC3-interacting region; MTORC1, mechanistic target of rapamycin complex 1; PE, phosphatidylethanolamine; PtdIns3K, phosphatidylinositol 3-kinase; PtdIns3P, phosphatidylinositol 3-phosphate; rDNA, ribosomal DNA; RFP, red fluorescent protein; RNAi, RNA interference; SQSTM1, sequestosome 1; TP53INP2, tumor protein p53-inducible nuclear protein 2; TP53INP2[1-28], TP53INP2 mutant containing amino acids 1 to 28; TP53INP2[28-45], TP53INP2 mutant containing amino acids 28 to 45; TP53INP2[LIRΔ], TP53INP2 mutant lacking amino acids 1 to 144; TP53INP2[NLSΔ], TP53INP2 mutant lacking amino acids 145 to 221; TP53INP2W35,I38A, TP53INP2 mutant in which tryptophan 35 and isoleucine 38 are replaced with alanine; TP53INP2W35,I38A[NLSΔ], TP53INP2 mutant lacking amino acids 145 to 221, and tryptophan 35 and isoleucine 38 are replaced with alanine; TP53INP2W35,I38A[Δ1-28],[NLSΔ], TP53INP2 mutant lacking amino acids 1 to 28 and amino acids 145 to 221, and tryptophan 35 and isoleucine 38 are replaced with alanine; TP53INP2[Δ1-28],[NLSΔ], TP53INP2 mutant lacking amino acids 1 to 28 and amino acids 145 to 221; TP53INP2[Δ67-111],[NLSΔ], TP53INP2 mutant lacking amino acids 67 to 111 and amino acids 145 to 221; TP53INP2[Δ112-144],[NLSΔ], TP53INP2 mutant lacking amino acids 112 to 144 and amino acids 145 to 221; TUBB, tubulin beta class I; ULK1, unc-51 like autophagy activating kinase 1; VMP1, vacuole membrane protein 1; WIPI2, WD repeat domain phosphoinositide-interacting 2; WT, wild-type; ZFYVE1/DFCP1, zinc finger FYVE-type containing 1.
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Autofagossomos/metabolismo , Proteína 7 Relacionada à Autofagia/metabolismo , Proteínas Associadas aos Microtúbulos/metabolismo , Proteínas Nucleares/metabolismo , Animais , Autofagia , Citoplasma/metabolismo , Células HEK293 , Células HeLa , Humanos , Camundongos , Ligação ProteicaRESUMO
Autophagy receptor p62/SQSTM1 promotes the assembly and removal of ubiquitylated proteins by forming p62 bodies and mediating their encapsulation in autophagosomes. Here we show that under nutrient-deficient conditions, cellular p62 specifically undergoes acetylation, which is required for the formation and subsequent autophagic clearance of p62 bodies. We identify K420 and K435 in the UBA domain as the main acetylation sites, and TIP60 and HDAC6 as the acetyltransferase and deacetylase. Mechanically, acetylation at both K420 and K435 sites enhances p62 binding to ubiquitin by disrupting UBA dimerization, while K435 acetylation also directly increases the UBA-ubiquitin affinity. Furthermore, we show that acetylation of p62 facilitates polyubiquitin chain-induced p62 phase separation. Our results suggest an essential role of p62 acetylation in the selective degradation of ubiquitylated proteins in cells under nutrient stress, by specifically regulating the assembly of p62 bodies.
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Autofagossomos/metabolismo , Proteína Sequestossoma-1/metabolismo , Estresse Fisiológico , Ubiquitina/metabolismo , Proteínas Ubiquitinadas/metabolismo , Acetilação , Sobrevivência Celular/fisiologia , Células HEK293 , Células HeLa , Desacetilase 6 de Histona/metabolismo , Humanos , Lisina/metabolismo , Lisina Acetiltransferase 5/metabolismo , Agregados Proteicos/fisiologia , Ligação Proteica/fisiologia , Domínios Proteicos/fisiologia , Multimerização Proteica/fisiologia , ProteóliseRESUMO
Accumulating evidence has indicated a role for autophagy-related (Atgs) proteins in cell regulation which is independent of their autophagic activities. As the only known transmembrane protein essential for autophagy, Atg9 cycles between the trans-Golgi network (TGN) and endosomes. Here, we report a function for mammalian Atg9 (mAtg9) in the transport of lysosomal hydrolases which impacts the lysosomal degradation capacity. Depletion of mAtg9 inhibits the degradation of epidermal growth factor receptor and the maturation of cathepsin D and cathepsin L. mAtg9 interacts with adaptor protein-1 (AP1) and the cation-independent mannose-6-phosphate receptor, facilitating AP1 polymerization and the transport of cathepsin D from the TGN. These results suggest that mAtg9 may serve as a coreceptor of lysosomal hydrolases for their TGN export by cycling between the TGN and endosomes.
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Complexo 1 de Proteínas Adaptadoras/metabolismo , Proteínas Relacionadas à Autofagia/fisiologia , Hidrolases/metabolismo , Lisossomos/metabolismo , Rede trans-Golgi/metabolismo , Animais , Proteínas Relacionadas à Autofagia/metabolismo , Células Cultivadas , Células Eucarióticas/metabolismo , Complexo de Golgi/metabolismo , Células HEK293 , Células HeLa , Humanos , Mamíferos , Proteínas de Membrana/metabolismo , Proteínas de Membrana/fisiologia , Ligação Proteica , Transporte Proteico , Proteínas de Transporte Vesicular/metabolismo , Proteínas de Transporte Vesicular/fisiologiaRESUMO
Cells control their metabolism through modulating the anabolic and catabolic pathways. TP53INP2/DOR (tumor protein p53 inducible nuclear protein 2), participates in cell catabolism by serving as a promoter of autophagy. Here we uncover a novel function of TP53INP2 in protein synthesis, a major biosynthetic and energy-consuming anabolic process. TP53INP2 localizes to the nucleolus through its nucleolar localization signal (NoLS) located at the C-terminal domain. Chromatin immunoprecipitation (ChIP) assays detected an association of TP53INP2 with the ribosomal DNA (rDNA), when exclusion of TP53INP2 from the nucleolus repressed rDNA promoter activity and the production of ribosomal RNA (rRNA) and proteins. The removal of TP53INP2 also impaired the association of the POLR1/RNA polymerase I preinitiation complex (PIC) with rDNA. Further, TP53INP2 interacts directly with POLR1 PIC, and is required for the assembly of the complex. These data indicate that TP53INP2 promotes ribosome biogenesis through facilitating rRNA synthesis at the nucleolus, suggesting a dual role of TP53INP2 in cell metabolism, assisting anabolism on the nucleolus, and stimulating catabolism off the nucleolus.
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Autofagia/genética , DNA Ribossômico/metabolismo , Proteínas Nucleares/metabolismo , Regiões Promotoras Genéticas/genética , RNA Polimerase I/metabolismo , Humanos , Células MCF-7 , Proteínas Nucleares/genética , Ligação Proteica , RNA Polimerase I/genética , Transcrição Gênica/genéticaRESUMO
Strict selection of patients for minimally invasive percutaneous nephrolithotomy could effectively improve the success rate of surgery. This study aimed to understand the required skills and the efficacy of mini-PCNL in the treatment of five types of upper ureteral calculi. Data collected after X-ray analysis and B mode ultrasound from 633 patients with upper ureteral and renal pelvis calculi who underwent B ultrasound-guided lithotomy was reviewed, including the following: type I, upper ureteral or renal pelvis calculi with moderate hydronephrosis (154 cases); type II, upper ureteral or renal pelvis calculi with severe hydronephrosis (157 cases); type III, upper ureteral or renal pelvis calculi without hydronephrosis (61 cases); type IV, renal pelvis calculi, one or two renal calyx calculi (206 cases); and type V, renal staghorn calculi (55 cases). Operations on 611 cases were successful. The treatment method for five patients was converted to open surgery. Twelve cases were treated by indwelling double-J tube retro-catheterization and extracorporeal shock wave lithotripsy. Five patients gave up the treatment. The rate of calculus clearance was 82.3 %, and the rate of residual calculus was 17.6 %. Selective renal artery embolization was performed in nine cases. Hydropneumothorax occurred in nine cases. No intestinal fistula occurred, and no patient had to undergo nephrectomy. The difficulty and the curative effect of the operation were different because the types of calculi varied. Selection of the procedure based on the different types of calculi could effectively improve the success rate of the procedure, reduce complications, and shorten the learning curve.
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[This corrects the article DOI: 10.1007/s12262-014-1043-4.].