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1.
Sci Rep ; 14(1): 6379, 2024 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-38493244

RESUMO

The regulatory mechanism of long non-coding RNAs (lncRNAs) in autophagy is as yet not well established. In this research, we show that the long non-coding RNA MLLT4 antisense RNA 1 (lncRNA MLLT4-AS1) is induced by the MTORC inhibitor PP242 and rapamycin in cervical cells. Overexpression of MLLT4-AS1 promotes autophagy and inhibits tumorigenesis and the migration of cervical cancer cells, whereas knockdown of MLLT4-AS1 attenuates PP242-induced autophagy. Mass spectrometry, RNA fluorescence in situ hybridization (RNA-FISH), and immunoprecipitation assays were performed to identify the direct interactions between MLLT4-AS1 and other associated targets, such as myosin-9 and autophagy-related 14(ATG14). MLLT4-AS1 was upregulated by H3K27ac modification with PP242 treatment, and knockdown of MLLT4-AS1 reversed autophagy by modulating ATG14 expression. Mechanically, MLLT4-AS1 was associated with the myosin-9 protein, which further promoted the transcription activity of the ATG14 gene. In conclusion, we demonstrated that MLLT4-AS1 acts as a potential tumor suppressor in cervical cancer by inducing autophagy, and H3K27ac modification-induced upregulation of MLLT4-AS1 could cause autophagy by associating with myosin-9 and promoting ATG14 transcription.


Assuntos
Proteínas Adaptadoras de Transporte Vesicular , MicroRNAs , RNA Longo não Codificante , Neoplasias do Colo do Útero , Feminino , Humanos , RNA Antissenso/genética , RNA Antissenso/metabolismo , RNA Longo não Codificante/metabolismo , Neoplasias do Colo do Útero/genética , Hibridização in Situ Fluorescente , Linhagem Celular Tumoral , Proliferação de Células/genética , Carcinogênese/genética , Transformação Celular Neoplásica/genética , Proteínas do Citoesqueleto/metabolismo , Miosinas/genética , Miosinas/metabolismo , Autofagia/genética , MicroRNAs/genética , Regulação Neoplásica da Expressão Gênica , Proteínas Relacionadas à Autofagia/genética
2.
Sci Rep ; 14(1): 6049, 2024 03 13.
Artigo em Inglês | MEDLINE | ID: mdl-38472280

RESUMO

The ubiquitin-adaptor protein UBQLN2 promotes degradation of several aggregate-prone proteins implicated in neurodegenerative diseases. Missense UBQLN2 mutations also cause X-linked amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). Previously we demonstrated that the liquid-like properties of UBQLN2 molecular assemblies are altered by a specific pathogenic mutation, P506T, and that the propensity of UBQLN2 to aggregate correlated with neurotoxicity. Here, we systematically assess the effects of multiple, spatially distinct ALS/FTD-linked missense mutations on UBQLN2 aggregation propensity, neurotoxicity, phase separation, and autophagic flux. In contrast to what we observed for the P506T mutation, no other tested pathogenic mutant exhibited a clear correlation between aggregation propensity and neurotoxicity. These results emphasize the unique nature of pathogenic UBQLN2 mutations and argue against a generalizable link between aggregation propensity and neurodegeneration in UBQLN2-linked ALS/FTD.


Assuntos
Esclerose Amiotrófica Lateral , Demência Frontotemporal , Humanos , Demência Frontotemporal/genética , Esclerose Amiotrófica Lateral/metabolismo , Proteínas Relacionadas à Autofagia/genética , Mutação , Proteínas Adaptadoras de Transdução de Sinal/metabolismo
3.
Nat Commun ; 15(1): 2465, 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38548722

RESUMO

Chronic HIV-1 infection is characterized by T-cell dysregulation that is partly restored by antiretroviral therapy. Autophagy is a critical regulator of T-cell function. Here, we demonstrate a protective role for autophagy in HIV-1 disease pathogenesis. Targeted analysis of genetic variation in core autophagy gene ATG16L1 reveals the previously unidentified rs6861 polymorphism, which correlates functionally with enhanced autophagy and clinically with improved survival of untreated HIV-1-infected individuals. T-cells carrying ATG16L1 rs6861(TT) genotype display improved antiviral immunity, evidenced by increased proliferation, revamped immune responsiveness, and suppressed exhaustion/immunosenescence features. In-depth flow-cytometric and transcriptional profiling reveal T-helper-cell-signatures unique to rs6861(TT) individuals with enriched regulation of pro-inflammatory networks and skewing towards immunoregulatory phenotype. Therapeutic enhancement of autophagy recapitulates the rs6861(TT)-associated T-cell traits in non-carriers. These data underscore the in vivo relevance of autophagy for longer-lasting T-cell-mediated HIV-1 control, with implications towards development of host-directed antivirals targeting autophagy to restore immune function in chronic HIV-1 infection.


Assuntos
Infecções por HIV , HIV-1 , Humanos , HIV-1/genética , Proteínas Relacionadas à Autofagia/genética , Polimorfismo Genético , Autofagia/genética , Infecções por HIV/tratamento farmacológico , Infecções por HIV/genética
4.
J Cell Mol Med ; 28(8): e18261, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38526029

RESUMO

We aimed to explore the biological function of CPNE7 and determine the impact of CPNE7 on chemotherapy resistance in colorectal cancer (CRC) patients. According to the Gene Expression Profiling Interactive Analysis database and previously published data, CPNE7 was identified as a potential oncogene in CRC. RT-qPCR and Western blotting were performed to verify the expression of CPNE7. Chi-square test was used to evaluate the associations between CPNE7 and clinical features. Cell proliferation, colony formation, cell migration and invasion, cell cycle and apoptosis were assessed to determine the effects of CPNE7. Transcriptome sequencing was used to identify potential downstream regulatory genes, and gene set enrichment analysis was performed to investigate downstream pathways. The effect of CPNE7 on 5-fluorouracil chemosensitivity was verified by half maximal inhibitory concentration (IC50). Subcutaneous tumorigenesis assay was used to examine the role of CPNE7 in sensitivity of CRC to chemotherapy in vivo. Transmission electron microscopy was used to detect autophagosomes. CPNE7 was highly expressed in CRC tissues, and its expression was correlated with T stage and tumour site. Knockdown of CPNE7 inhibited the proliferation and colony formation of CRC cells and promoted apoptosis. Knockdown of CPNE7 suppressed the expression of ATG9B and enhanced the sensitivity of CRC cells to 5-fluorouracil in vitro and in vivo. Knockdown of CPNE7 reversed the induction of the autophagy pathway by rapamycin and reduced the number of autophagosomes. Depletion of CPNE7 attenuated the malignant proliferation of CRC cells and enhanced the chemosensitivity of CRC cells to 5-fluorouracil.


Assuntos
Neoplasias Colorretais , Fluoruracila , Humanos , Fluoruracila/farmacologia , Fluoruracila/uso terapêutico , Linhagem Celular Tumoral , Transformação Celular Neoplásica/genética , Carcinogênese/genética , Proliferação de Células/genética , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Regulação Neoplásica da Expressão Gênica , Proteínas Relacionadas à Autofagia/genética , Proteínas Relacionadas à Autofagia/metabolismo , Proteínas de Membrana/genética
5.
BMC Cancer ; 24(1): 283, 2024 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-38431566

RESUMO

BACKGROUND: This study aims to investigate the expression of UBQLN1 in lung cancer (LC) tissue and the diagnostic capability of autoantibody to UBQLN1 (anti-UBQLN1) in the detection of LC and the discrimination of pulmonary nodules (PNs). METHODS: Sera from 798 participants were used to discover and validate the level of autoantibodies via HuProt microarray and Enzyme-linked immunosorbent assay (ELISA). Logistic regression analysis was applied to establish model. Receiver operating characteristic curve (ROC) analysis was performed to evaluate the diagnostic potential. Immunohistochemistry was performed to detect UBQLN1 expression in 88 LC tissues and 88 para-tumor tissues. qRT-PCR and western blotting were performed to detect the expression of UBQLN1 at the mRNA and protein levels, respectively. Trans-well assay and cell counting kit-8 (CCK-8) was used to investigate the function of UBQLN1. RESULTS: Anti-UBQLN1 was identified with the highest fold change by protein microarray. The level of anti-UBQLN1 in LC patients was obviously higher than that in NC or patients with benign lung disease of validation cohort 1 (P<0.05). The area under the curve (AUC) of anti-UBQLN1 was 0.610 (95%CI: 0.508-0.713) while reached at 0.822 (95%CI: 0.784-0.897) when combining anti-UBQLN1 with CEA, CYFRA21-1, CA125 and three CT indicators (vascular notch sign, lobulation sign and mediastinal lymph node enlargement) in the discrimination of PNs. UBQLN1 protein was overexpressed in lung adenocarcinoma (LUAD) tissues compared to para-tumor tissues. UBQLN1 knockdown remarkably inhibited the migration, invasion and proliferation of LUAD cell lines. CONCLUSIONS: Anti-UBQLN1 might be a potential biomarker for the diagnosis of LC and the discrimination of PNs.


Assuntos
Adenocarcinoma de Pulmão , Neoplasias Pulmonares , Nódulos Pulmonares Múltiplos , Humanos , Neoplasias Pulmonares/diagnóstico , Imunidade Humoral , Antígenos de Neoplasias , Queratina-19 , Biomarcadores Tumorais , Proteínas Relacionadas à Autofagia/genética , Proteínas Adaptadoras de Transdução de Sinal/genética
6.
Nat Cell Biol ; 26(3): 366-377, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38316984

RESUMO

Cells convert complex metabolic information into stress-adapted autophagy responses. Canonically, multilayered protein kinase networks converge on the conserved Atg1/ULK kinase complex (AKC) to induce non-selective and selective forms of autophagy in response to metabolic changes. Here we show that, upon phosphate starvation, the metabolite sensor Pho81 interacts with the adaptor subunit Atg11 at the AKC via an Atg11/FIP200 interaction motif to modulate pexophagy by virtue of its conserved phospho-metabolite sensing SPX domain. Notably, core AKC components Atg13 and Atg17 are dispensable for phosphate starvation-induced autophagy revealing significant compositional and functional plasticity of the AKC. Our data indicate that, instead of functioning as a selective autophagy receptor, Pho81 compensates for partially inactive Atg13 by promoting Atg11 phosphorylation by Atg1 critical for pexophagy during phosphate starvation. Our work shows Atg11/FIP200 adaptor subunits bind not only selective autophagy receptors but also modulator subunits that convey metabolic information directly to the AKC for autophagy regulation.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal , Macroautofagia , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas Relacionadas à Autofagia/genética , Proteínas Relacionadas à Autofagia/metabolismo , Proteínas de Transporte/metabolismo , Autofagia/fisiologia , Fagossomos/metabolismo , Fatores de Transcrição/metabolismo , Fosfatos/metabolismo
7.
Sci Adv ; 10(6): eadj8027, 2024 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-38324698

RESUMO

The covalent attachment of ubiquitin-like LC3 proteins (microtubule-associated proteins 1A/1B light chain 3) prepares the autophagic membrane for cargo recruitment. We resolve key steps in LC3 lipidation by combining molecular dynamics simulations and experiments in vitro and in cellulo. We show how the E3-like ligaseautophagy-related 12 (ATG12)-ATG5-ATG16L1 in complex with the E2-like conjugase ATG3 docks LC3 onto the membrane in three steps by (i) the phosphatidylinositol 3-phosphate effector protein WD repeat domain phosphoinositide-interacting protein 2 (WIPI2), (ii) helix α2 of ATG16L1, and (iii) a membrane-interacting surface of ATG3. Phosphatidylethanolamine (PE) lipids concentrate in a region around the thioester bond between ATG3 and LC3, highlighting residues with a possible role in the catalytic transfer of LC3 to PE, including two conserved histidines. In a near-complete pathway from the initial membrane recruitment to the LC3 lipidation reaction, the three-step targeting of the ATG12-ATG5-ATG16L1 machinery establishes a high level of regulatory control.


Assuntos
Autofagossomos , Proteínas Associadas aos Microtúbulos , Proteínas Relacionadas à Autofagia/genética , Proteínas Relacionadas à Autofagia/metabolismo , Autofagossomos/metabolismo , Proteínas Associadas aos Microtúbulos/metabolismo , Fagocitose , Autofagia
8.
Sci Rep ; 14(1): 546, 2024 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-38177147

RESUMO

Selective degradation of dysfunctional or excess mitochondria is a fundamental process crucial for cell homeostasis in almost all eukaryotes. This process relies on autophagy, an intracellular self-eating system conserved from yeast to humans and is thus called mitophagy. Detailed mechanisms of mitophagy remain to be fully understood. Here we show that mitochondrial degradation in budding yeast, which requires the pro-mitophagic protein Atg32, is strongly reduced in cells lacking Egd1, a beta subunit of the nascent polypeptide-associated complex acting in cytosolic ribosome attachment and protein targeting to mitochondria. By contrast, loss of the sole alpha subunit Egd2 or the beta subunit paralogue Btt1 led to only a partial or slight reduction in mitophagy. We also found that phosphorylation of Atg32, a crucial step for priming mitophagy, is decreased in the absence of Egd1. Forced Atg32 hyperphosphorylation almost completely restored mitophagy in egd1-null cells. Together, we propose that Egd1 acts in Atg32 phosphorylation to facilitate mitophagy.


Assuntos
Proteínas de Ligação a DNA , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae , Fatores de Transcrição , Proteínas Relacionadas à Autofagia/genética , Proteínas Relacionadas à Autofagia/metabolismo , Mitofagia , Peptídeos/metabolismo , Receptores Citoplasmáticos e Nucleares/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Mitocôndrias , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo
9.
EMBO Rep ; 25(2): 813-831, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38233718

RESUMO

Autophagy is initiated by the assembly of multiple autophagy-related proteins that form the phagophore assembly site where autophagosomes are formed. Atg13 is essential early in this process, and a hub of extensive phosphorylation. How these multiple phosphorylations contribute to autophagy initiation, however, is not well understood. Here we comprehensively analyze the role of phosphorylation events on Atg13 during nutrient-rich conditions and nitrogen starvation. We identify and functionally characterize 48 in vivo phosphorylation sites on Atg13. By generating reciprocal mutants, which mimic the dephosphorylated active and phosphorylated inactive state of Atg13, we observe that disrupting the dynamic regulation of Atg13 leads to insufficient or excessive autophagy, which are both detrimental to cell survival. We furthermore demonstrate an involvement of Atg11 in bulk autophagy even during nitrogen starvation, where it contributes together with Atg1 to the multivalency that drives phase separation of the phagophore assembly site. These findings reveal the importance of post-translational regulation on Atg13 early during autophagy initiation, which provides additional layers of regulation to control bulk autophagy activity and integrate cellular signals.


Assuntos
Autofagia , Proteínas de Saccharomyces cerevisiae , Fosforilação , Autofagia/fisiologia , Proteínas Relacionadas à Autofagia/genética , Proteínas Relacionadas à Autofagia/metabolismo , Transdução de Sinais , Nitrogênio , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo
10.
BMJ Case Rep ; 17(1)2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-38182173

RESUMO

Vici syndrome is a genetic disorder involving autophagy dysfunction caused by biallelic pathogenic variants in ectopic P-granules 5 autophagy tethering factor (EPG5). We report the perinatal clinical course of a neonate with Vici syndrome with a unique cardiac presentation. Foetal ultrasonography (US) detected right ventricular hypertrophy, hypoplastic left ventricle and narrowing of the foramen ovale, which were alleviated after birth. Agenesis of the corpus callosum and cerebellar hypoplasia were missed antenatally. After delivery, the patient was clinically diagnosed with Vici syndrome and two novel pathogenic mutations were detected in EPG5 The T-cell receptor repertoire was selectively skewed in the Vß2 family. Immunological prophylaxis and tube feeding were introduced. Early diagnosis helps parents accept their child's prognosis and decide on a care plan. However, US has limited potential to detect clinical phenotypes associated with Vici syndrome. Foetal MRI may detect the characteristic abnormalities and contribute to antenatal diagnosis.


Assuntos
Catarata , Diagnóstico Pré-Natal , Feminino , Gravidez , Criança , Recém-Nascido , Humanos , Coração , Progressão da Doença , Proteínas Relacionadas à Autofagia/genética , Proteínas de Transporte Vesicular
11.
Mol Biol Rep ; 51(1): 231, 2024 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-38281293

RESUMO

BACKGROUND: In India, esophageal cancer (EC) is among the major cause of cancer-related deaths in both sexes. In recent past, autophagy has emerged as one of the crucial process associated with cancer. In the development of EC, the role of autophagy and the precise molecular mechanism involved has yet to be fully understood. Recently, a small number of studies have proposed how variations in autophagy genes affect the growth and development of EC. Micro-RNA's are also known to play a critical role in the development of EC. Here, we examined the relationship between the risk of EC and two single-nucleotide polymorphisms (SNPs) in the key autophagy genes, ATG10 rs1864183 and ATG16L1 rs2241880. We also analyzed the association of miR-107 and miR-126 with EC as these miRNA's are associated with autophagy. METHODS AND RESULTS: A total of 230 EC patients and 230 healthy controls from North-west Indian population were enrolled. ATG10 rs1864183 and ATG16L1 rs2241880 polymorphism were analyzed using TaqMan genotyping assay. Expression levels of miR-107 and miR-126 were analyzed through quantitative PCR using SYBR green chemistry. We found significant association of CT + CC genotype (OR 0.64, p = 0.022) in recessive model for ATG10 rs1864183 polymorphism with decreased EC risk. For ATG16L1 rs2241880 polymorphism significant association for AG genotype (OR 1.48, p = 0.05) and G allele (OR 1.43, p = 0.025) was observed for increased EC risk. Expression levels of miR-126 were also found to be significantly up regulated (p = 0.008). CONCLUSION: Our results suggest that ATG10 rs1864183, ATG16L1 rs2241880 and miR-126 may be associated with esophageal carcinogenesis and warrant further investigation.


Assuntos
Neoplasias Esofágicas , MicroRNAs , Masculino , Feminino , Humanos , Predisposição Genética para Doença , Polimorfismo de Nucleotídeo Único/genética , Genótipo , Neoplasias Esofágicas/genética , MicroRNAs/genética , Proteínas Relacionadas à Autofagia/genética , Autofagia/genética , Estudos de Casos e Controles , Proteínas de Transporte Vesicular/genética
12.
J Gene Med ; 26(1): e3648, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38282156

RESUMO

BACKGROUND: Autophagy plays an important role in immunity and inflammation. The present study aimed to explore the prognostic significance of autophagy-related genes (ARGs) in endometrial cancer (EC) using bioinformatics. METHODS: The list of ARGs was obtained from the Human Autophagy Database. The differentially expressed ARGs (DEARGs) between the EC and normal endometrial tissue samples were screened from The Cancer Genome Atlas database. Cox regression analysis was performed on the DEARGs to screen the prognostic ARGs and construct risk signatures for overall survival (OS) and progression-free survival (PFS). The hub ARGs were identified from a protein-protein interaction network, and CDKN2A was obtained from the intersection of prognostic ARGs and hub ARGs. The association of CDKN2A expression with clinical characteristics and immune infiltration were analyzed. Finally, the role of CDKN2A in autophagy was confirmed in EC cell lines. RESULTS: CDKN2A, PTK6 and DLC1 were used to establish risk signatures for predicting the survival of EC patients. Receiver operating characteristic curve analysis indicated that the risk signatures can accurately predict both OS and PFS. CDKN2A was the only hub prognostic ARG, and showed significant association with the age, survival status, grade, histological type, body mass index and FIGO (i.e. International Federation of Gynecology and Obstetrics) stage (p < 0.05). Furthermore, CDKN2A expression was also correlated with the infiltration of immune cells, indicating that CDKN2A might play a critical role in regulating the immune microenvironment and immune responses in EC. In addition, silencing of CDKN2A gene promoted autophagy in the HEC-1A cell line and upregulated the expression levels of autophagy-related proteins. CONCLUSIONS: CDKN2A is a prognostic factor and therapeutic target in EC, and is likely associated with the tumor immune landscape and autophagy.


Assuntos
Neoplasias do Endométrio , Feminino , Gravidez , Humanos , Neoplasias do Endométrio/diagnóstico , Neoplasias do Endométrio/genética , Autofagia/genética , Proteínas Relacionadas à Autofagia/genética , Linhagem Celular , Biologia Computacional , Microambiente Tumoral , Proteínas Ativadoras de GTPase , Proteínas Supressoras de Tumor
13.
Mol Biotechnol ; 66(1): 112-122, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37043109

RESUMO

Kruppel-like factor 15 (KLF15) is involved in many cardiovascular diseases and is abnormally expressed in atherosclerosis (AS), but the regulatory mechanism of KLF15 in AS has not been reported so far. RT-qPCR was used to detect the expression of KLF15 and ATG14 in AS patients. Subsequently, human aortic endothelial cells (HAECs) were induced by oxidized low densitylipoprotein (ox-LDL), and the expression of KLF15 in model cells was detected. KLF15 was overexpressed in cells by lipofection transfection, and then CCK8, flow cytometry, Western blot, ELISA, and related assay kits were used to detect cell viability, apoptosis, inflammatory response as well as oxidative stress, respectively. The targeted regulatory relationship between KLF15 and autophagy-related 14 (ATG14) was detected by ChIP and luciferase reporter assays. Following ATG14 silencing in KLF15-overexpressing cells, immunofluorescence and Western blot were used to detect the autophagy. Finally, after the addition of 3-Methyladenine (3-MA), an autophagy inhibitor, the aforementioned experiments were conducted again to further explore the mechanism. The expression of KLF15 and ATG14 were decreased in AS patients and ox-LDL-induced HAECs. Overexpression of KLF15 protected ox-LDL-induced HAECs from damage, which might be achieved through transcriptional regulation of ATG14. In addition, KLF15 could promote autophagy through transcriptional activation of ATG14. KLF15 transcriptionally activated ATG14 to promote autophagy and attenuate damage of ox-LDL-induced HAECs.


Assuntos
Células Endoteliais , MicroRNAs , Humanos , Células Endoteliais/metabolismo , Transdução de Sinais , Lipoproteínas LDL/farmacologia , Lipoproteínas LDL/metabolismo , Autofagia/genética , Apoptose , MicroRNAs/metabolismo , Fatores de Transcrição Kruppel-Like/genética , Fatores de Transcrição Kruppel-Like/metabolismo , Proteínas Relacionadas à Autofagia/genética , Proteínas Relacionadas à Autofagia/metabolismo , Proteínas Adaptadoras de Transporte Vesicular/metabolismo
14.
FEBS Lett ; 598(1): 107-113, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37259601

RESUMO

Autophagy is a highly conserved intracellular pathway that is essential for survival in all eukaryotes. In healthy cells, autophagy is used to remove damaged intracellular components, which can be as simple as unfolded proteins or as complex as whole mitochondria. Once the damaged component is captured, the autophagosome engulfs it and closes, isolating the content from the cytoplasm. The autophagosome then fuses with the late endosome and/or lysosome to deliver its content to the lysosome for degradation. Formation of the autophagosome, sequestration or capture of content, and closure all require the ATG proteins, which constitute the essential core autophagy protein machinery. This brief 'nutshell' will highlight recent data revealing the importance of small membrane-associated domains in the ATG proteins. In particular, recent findings from two parallel studies reveal the unexpected key role of α-helical structures in the ATG8 conjugation machinery and ATG8s. These studies illustrate how unique membrane association modules can control the formation of autophagosomes.


Assuntos
Autofagossomos , Autofagia , Autofagossomos/metabolismo , Família da Proteína 8 Relacionada à Autofagia/metabolismo , Proteínas Relacionadas à Autofagia/genética , Proteínas Relacionadas à Autofagia/metabolismo , Membranas/metabolismo , Proteínas Associadas aos Microtúbulos/metabolismo
15.
United European Gastroenterol J ; 12(1): 103-121, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37837511

RESUMO

BACKGROUND: ATG16L1 plays a fundamental role in the degradative intracellular pathway known as autophagy, being a mediator of inflammation and microbial homeostasis. The variant rs2241880 can diminish these capabilities, potentially contributing to inflammatory bowel disease (IBD) pathogenesis. OBJECTIVES: To perform an updated meta-analysis on the association between ATG16L1 rs2241880 and IBD susceptibility by exploring the impact of age, ethnicity, and geography. Moreover, to investigate the association between rs2241880 and clinical features. METHODS: Literature searches up until September 2022 across 7 electronic public databases were performed for all case-control studies on ATG16L1 rs2241880 and IBD. Pooled odds ratios (ORP ) and 95% CI were calculated under the random effects model. RESULTS: Our analyses included a total of 30,606 IBD patients, comprising 21,270 Crohn's disease (CD) and 9336 ulcerative colitis (UC) patients, and 33,329 controls. ATG16L1 rs2241880 was significantly associated with CD susceptibility, where the A allele was protective (ORP : 0.74, 95% CI: 0.72-0.77, p-value: <0.001), while the G allele was a risk factor (ORP : 1.23, 95% CI: 1.09-1.39, p-value: 0.001), depending on the minor allele frequencies observed in this multi-ancestry study sample. rs2241880 was predominantly relevant in Caucasians from North America and Europe, and in Latin American populations. Importantly, CD patients harbouring the G allele were significantly more predisposed to perianal disease (ORP : 1.21, 95% CI: 1.07-1.38, p-value: 0.003). CONCLUSIONS: ATG16L1 rs2241880 (G allele) is a consistent risk factor for IBD in Caucasian cohorts and influences clinical outcomes. As its role in non-Caucasian populations remains ambiguous, further studies in under-reported populations are necessary.


Assuntos
Doença de Crohn , Doenças Inflamatórias Intestinais , Humanos , Doença de Crohn/diagnóstico , Doença de Crohn/genética , Predisposição Genética para Doença , Genótipo , Polimorfismo de Nucleotídeo Único , Proteínas de Transporte/genética , Doenças Inflamatórias Intestinais/epidemiologia , Doenças Inflamatórias Intestinais/genética , Proteínas Relacionadas à Autofagia/genética
16.
FEBS Lett ; 598(1): 127-139, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38058212

RESUMO

The four human WIPI ß-propellers, WIPI1 through WIPI4, belong to the ancient PROPPIN family and fulfill scaffold functions in the control of autophagy. In this context, WIPI ß-propellers function as PI3P effectors during autophagosome formation and loss of WIPI function negatively impacts autophagy and contributes to neurodegeneration. Of particular interest are mutations in WDR45, the human gene that encodes WIPI4. Sporadic WDR45 mutations are the cause of a rare human neurodegenerative disease called BPAN, hallmarked by high brain iron accumulation. Here, we discuss the current understanding of the functions of human WIPI ß-propellers and address unanswered questions with a particular focus on the role of WIPI4 in autophagy and BPAN.


Assuntos
Proteínas de Transporte , Doenças Neurodegenerativas , Humanos , Proteínas de Transporte/genética , Doenças Neurodegenerativas/genética , Mutação , Proteínas Relacionadas à Autofagia/genética , Autofagia/genética
17.
FEBS Lett ; 598(1): 73-83, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37585559

RESUMO

Macroautophagy, hereafter referred to as autophagy, is a complex process in which multiple membrane-remodeling events lead to the formation of a cisterna known as the phagophore, which then expands and closes into a double-membrane vesicle termed the autophagosome. During the past decade, enormous progress has been made in understanding the molecular function of the autophagy-related proteins and their role in generating these phagophores. In this Review, we discuss the current understanding of three membrane remodeling steps in autophagy that remain to be largely characterized; namely, the closure of phagophores, the maturation of the resulting autophagosomes into fusion-competent vesicles, and their fusion with vacuoles/lysosomes. Our review will mainly focus on the yeast Saccharomyces cerevisiae, which has been the leading model system for the study of molecular events in autophagy and has led to the discovery of the major mechanistic concepts, which have been found to be mostly conserved in higher eukaryotes.


Assuntos
Autofagossomos , Proteínas de Saccharomyces cerevisiae , Autofagossomos/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Macroautofagia , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Vacúolos/metabolismo , Autofagia/genética , Proteínas Relacionadas à Autofagia/genética , Proteínas Relacionadas à Autofagia/metabolismo
18.
FEBS Lett ; 598(1): 114-126, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37567770

RESUMO

Autophagy is a process of regulated degradation. It eliminates damaged and unnecessary cellular components by engulfing them with a de novo-generated organelle: the double-membrane autophagosome. The past three decades have provided us with a detailed parts list of the autophagy initiation machinery, have developed important insights into how these processes function and have identified regulatory proteins. It is now clear that autophagosome biogenesis requires the timely assembly of a complex machinery. However, it is unclear how a putative stable machine is assembled and disassembled and how the different parts cooperate to perform its overall function. Although they have long been somewhat enigmatic in their precise role, HORMA domain proteins (first identified in Hop1p, Rev7p and MAD2 proteins) autophagy-related protein 13 (ATG13) and ATG101 of the ULK-kinase complex have emerged as important coordinators of the autophagy-initiating subcomplexes. Here, we will particularly focus on ATG13 and ATG101 and the role of their unusual metamorphosis in initiating autophagosome biogenesis. We will also explore how this metamorphosis could potentially be purposefully rate-limiting and speculate on how it could regulate the spontaneous self-assembly of the autophagy-initiating machinery.


Assuntos
Autofagossomos , Autofagia , Proteínas Relacionadas à Autofagia/genética , Autofagia/fisiologia , Proteínas Mad2
19.
Eur J Clin Invest ; 54(3): e14135, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37991085

RESUMO

BACKGROUND: Although mounting evidence supports that aberrant DNA methylation occurs in the hearts of patients with atrial fibrillation (AF), noninvasive epigenetic characterization of AF has not yet been defined. METHODS: We investigated DNA methylome changes in peripheral blood CD4+ T cells isolated from 10 patients with AF relative to 11 healthy subjects (HS) who were enrolled in the DIANA clinical trial (NCT04371809) via reduced-representation bisulfite sequencing (RRBS). RESULTS: An atrial-specific PPI network revealed 18 hub differentially methylated genes (DMGs), wherein ROC curve analysis revealed reasonable diagnostic performance of DNA methylation levels found within CDK5R1 (AUC = 0.76; p = 0.049), HSPG2 (AUC = 0.77; p = 0.038), WDFY3 (AUC = 0.78; p = 0.029), USP49 (AUC = 0.76; p = 0.049), GSE1 (AUC = 0.76; p = 0.049), AIFM1 (AUC = 0.76; p = 0.041), CDK5RAP2 (AUC = 0.81; p = 0.017), COL4A1 (AUC = 0.86; p < 0.001), SEPT8 (AUC = 0.90; p < 0.001), PFDN1 (AUC = 0.90; p < 0.01) and ACOT7 (AUC = 0.78; p = 0.032). Transcriptional profiling of the hub DMGs provided a significant overexpression of PSDM6 (p = 0.004), TFRC (p = 0.01), CDK5R1 (p < 0.001), HSPG2 (p = 0.01), WDFY3 (p < 0.001), USP49 (p = 0.004) and GSE1 (p = 0.021) in AF patients vs HS. CONCLUSIONS: CDK5R1, GSE1, HSPG2 and WDFY3 resulted the best discriminatory genes both at methylation and gene expression level. Our results provide several candidate diagnostic biomarkers with the potential to advance precision medicine in AF.


Assuntos
Fibrilação Atrial , Humanos , Metilação de DNA , Átrios do Coração , Análise de Sequência de DNA , Epigênese Genética , Proteínas do Tecido Nervoso/genética , Proteínas de Ciclo Celular/genética , Proteínas Relacionadas à Autofagia/genética , Proteínas Adaptadoras de Transdução de Sinal/genética , Ubiquitina Tiolesterase/genética , Proteínas de Neoplasias/genética
20.
Microbiol Immunol ; 68(2): 47-55, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37991129

RESUMO

Hepatitis B virus (HBV) infection is a severe public health problem worldwide. The relationship between polymorphisms of autophagy-related 16-like 1 gene (ATG16L1) and autophagy-related gene 5 (ATG5) with susceptibility to the stage of HBV infection has been reported in different populations. Nevertheless, this association is not seen in the population of central China. This study recruited 452 participants, including 246 HBV-infected patients (139 chronically infected HBV without hepatocellular carcinoma [HCC] and 107 HBV-related HCC patients) and 206 healthy controls. Genotyping of ATG16L1 rs2241880 and ATG5 rs688810 were performed using Sanger sequencing and polymerase chain reaction-restriction fragment length polymorphism, respectively. Our results indicated that the G allele of ATG16L1 rs2241880 was more frequent in healthy controls than in patients with chronicHBV infection. After adjusting for age and sex, an association between the ATG16L1 rs2241880 polymorphism and HBV infection was significant under the dominant and allele models (p = 0.009 and 0.003, respectively). However, no association between the ATG5 polymorphisms and HBV infection was observed. We also did not find a significant association between ATG16L1 and ATG5 polymorphisms and the progression of HBV-related HCC. Therefore, the genetic polymorphism of ATG16L1 rs2241880 may be associated with susceptibility to HBV infection in the population of central China.


Assuntos
Carcinoma Hepatocelular , Hepatite B , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/complicações , Vírus da Hepatite B , Neoplasias Hepáticas/genética , Genótipo , Frequência do Gene , Predisposição Genética para Doença , Polimorfismo de Nucleotídeo Único , Hepatite B/complicações , Hepatite B/genética , China , Estudos de Casos e Controles , Proteína 5 Relacionada à Autofagia/genética , Proteínas Relacionadas à Autofagia/genética
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