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Nature Communications May 2024Triazoles are widely used to control pathogenic fungi. They inhibit the ergosterol biosynthetic pathway, but the precise mechanisms leading to fungicidal activities in...
Triazoles are widely used to control pathogenic fungi. They inhibit the ergosterol biosynthetic pathway, but the precise mechanisms leading to fungicidal activities in many fungal pathogens are poorly understood. Here, we elucidate the mode of action of epoxiconazole and metconazole in the wheat pathogen Zymoseptoria tritici and the rice blast fungus Magnaporthe oryzae. We show that both azoles have fungicidal activity and reduce fluidity, but not integrity, of the plasma membrane. This impairs localisation of Cdc15-like F-BAR proteins, resulting in defective actin ring assembly and incomplete septation. However, mutant studies and pharmacological experiments in vitro and in planta show that azole lethality is due to a combination of reactive oxygen species-induced apoptosis and macroautophagy. Simultaneous inhibition of both programmed cell death pathways abolishes azole-induced cell death. Other classes of ergosterol biosynthesis inhibitors also induce apoptosis and macroautophagy, suggesting that activation of these two cell death pathways is a hallmark of ergosterol synthesis-targeting fungicides. This knowledge will inform future crop protection strategies.
Topics: Apoptosis; Plant Diseases; Ascomycota; Fungicides, Industrial; Reactive Oxygen Species; Triticum; Azoles; Ergosterol; Fungal Proteins; Autophagy; Cell Membrane; Oryza; Triazoles; Crops, Agricultural
PubMed: 38821954
DOI: 10.1038/s41467-024-48157-9 -
European Journal of Pharmacology May 2024Transient receptor potential channels (TRPs) are widely recognized as a group of ion channels involved in various sensory perceptions, such as temperature, taste,... (Review)
Review
Transient receptor potential channels (TRPs) are widely recognized as a group of ion channels involved in various sensory perceptions, such as temperature, taste, pressure, and vision. While macroautophagy (hereafter referred to as autophagy) is primarily regulated by core machinery, the ion exchange mediated by TRPs between intracellular and extracellular compartments, as well as within organelles and the cytoplasm, plays a crucial role in autophagy regulation as an important signaling transduction mechanism. Moreover, certain TRPs can directly interact with autophagy regulatory proteins to participate in autophagy regulation. In this article, we provide an in-depth review of the current understanding of the regulatory mechanisms of autophagy, with a specific focus on TRPs. Furthermore, we highlight the potential prospects for drug development targeting TRPs in autophagy for the treatment of human diseases.
PubMed: 38821165
DOI: 10.1016/j.ejphar.2024.176681 -
Autophagy Jun 2024strains producing the genotoxin colibactin, designated as CoPEC (colibactin-producing ), have emerged as an important player in the etiology of colorectal cancer (CRC)....
strains producing the genotoxin colibactin, designated as CoPEC (colibactin-producing ), have emerged as an important player in the etiology of colorectal cancer (CRC). Here, we investigated the role of macroautophagy/autophagy in myeloid cells, an important component of the tumor microenvironment, in the tumorigenesis of a susceptible mouse model infected with CoPEC. For that, a preclinical mouse model of CRC, the mice, with deficiency specifically in myeloid cells (/) and the corresponding control mice (), were infected with a clinical CoPEC strain 11G5 or its isogenic mutant 11G5 that does not produce colibactin. We showed that myeloid cell-specific deficiency led to an increase in the volume of colonic tumors in mice under infection with 11G5, but not with 11G5. This was accompanied by increased colonocyte proliferation, enhanced inflammasome activation and IL1B/IL-1β secretion, increased neutrophil number and decreased total T cell and cytotoxic CD8 T cell numbers in the colonic mucosa and tumors. In bone marrow-derived macrophages (BMDMs), compared to uninfected and 11G5∆-infected conditions, 11G5 infection increased inflammasome activation and IL1B secretion, and this was further enhanced by autophagy deficiency. These data indicate that ATG16L1 in myeloid cells was necessary to inhibit colonic tumor growth in CoPEC-infected mice inhibiting colibactin-induced inflammasome activation and modulating immune cell response in the tumor microenvironment. : AOM, azoxymethane; APC, APC regulator of WNT signaling pathway; ATG, autophagy related; mice, mice deficient for specifically in myeloid cells; CASP1, caspase 1; BMDM, bone marrow-derived macrophage; CFU, colony-forming unit; CoPEC, colibactin-producing ; CRC, colorectal cancer; CXCL1/KC, C-X-C motif chemokine ligand 1; ELISA, enzyme-linked immunosorbent assay; IL, interleukin; MC, myeloid cell; MOI, multiplicity of infection; PBS, phosphate-buffered saline; , polyketide synthase; qRT-PCR, quantitative real-time reverse-transcription polymerase chain reaction; siRNA, small interfering RNA; TME, tumor microenvironment; TNF/TNF-α, tumor necrosis factor.
PubMed: 38818900
DOI: 10.1080/15548627.2024.2359770 -
Autophagy May 2024Many bacterial pathogens have evolved effective strategies to interfere with the ubiquitination network to evade clearance by the innate immune system. Here, we report...
Many bacterial pathogens have evolved effective strategies to interfere with the ubiquitination network to evade clearance by the innate immune system. Here, we report that OTUB1, one of the most abundant deubiquitinases (DUBs) in mammalian cells, is subjected to both canonical and noncanonical ubiquitination during infection. The effectors SidC and SdcA catalyze OTUB1 ubiquitination at multiple lysine residues, resulting in its association with a -containing vacuole. Lysine ubiquitination by SidC and SdcA promotes interactions between OTUB1 and DEPTOR, an inhibitor of the MTORC1 pathway, thus suppressing MTORC1 signaling. The inhibition of MTORC1 leads to suppression of host protein synthesis and promotion of host macroautophagy/autophagy during infection. In addition, members of the SidE family effectors (SidEs) induce phosphoribosyl (PR)-linked ubiquitination of OTUB1 at Ser16 and Ser18 and block its DUB activity. The levels of the lysine and serine ubiquitination of OTUB1 are further regulated by effectors that function to antagonize the activities of SidC, SdcA and SidEs, including Lem27, DupA, DupB, SidJ and SdjA. Our study reveals an effectors-mediated complicated mechanism in regulating the activity of a host DUB.: BafA1: bafilomycin A; BMDMs: bone marrow-derived macrophages; DUB: deubiquitinase; Dot/Icm: defective for organelle trafficking/intracellular multiplication; DEPTOR: DEP domain containing MTOR interacting protein; GAPDH: glyceraldehyde-3-phosphate dehydrogenase; : ; LCV: -ontaining acuole; MAP1LC3/LC3: microtubule associated protein 1 light chain 3; MOI: multiplicity of infection; MTORC1: mechanistic target of rapamycin kinase complex 1; OTUB1: OTU deubiquitinase, ubiquitin aldehyde binding 1; PR-Ub: phosphoribosyl (PR)-linked ubiquitin; PTM: posttranslational modification; SDS-PAGE: sodium dodecyl sulfate-polyacrylamide gel electrophoresis; SidEs: SidE family effectors; Ub: ubiquitin.
PubMed: 38818749
DOI: 10.1080/15548627.2024.2353492 -
Frontiers in Cellular and Infection... 2024Parasites possess remarkable abilities to evade and manipulate the immune response of their hosts. is a parasitic tapeworm that causes cystic echinococcosis in animals...
Parasites possess remarkable abilities to evade and manipulate the immune response of their hosts. is a parasitic tapeworm that causes cystic echinococcosis in animals and humans. The hydatid fluid released by the parasite is known to contain various immunomodulatory components that manipulate host´s defense mechanism. In this study, we focused on understanding the effect of hydatid fluid on dendritic cells and its impact on autophagy induction and subsequent T cell responses. Initially, we observed a marked downregulation of two C-type lectin receptors in the cell membrane, CLEC9A and CD205 and an increase in lysosomal activity, suggesting an active cellular response to hydatid fluid. Subsequently, we visualized ultrastructural changes in stimulated dendritic cells, revealing the presence of macroautophagy, characterized by the formation of autophagosomes, phagophores, and phagolysosomes in the cell cytoplasm. To further elucidate the underlying molecular mechanisms involved in hydatid fluid-induced autophagy, we analyzed the expression of autophagy-related genes in stimulated dendritic cells. Our results demonstrated a significant upregulation of and , indicating the induction of autophagy machinery in response to hydatid fluid exposure. Additionally, using confocal microscopy, we observed an accumulation of LC3 in dendritic cell autophagosomes, confirming the activation of this catabolic pathway associated with antigen presentation. Finally, to evaluate the functional consequences of hydatid fluid-induced autophagy in DCs, we evaluated cytokine transcription in the splenocytes. Remarkably, a robust polyfunctional T cell response, with inhibition of Th2 profile, is characterized by an increase in the expression of and genes. These findings suggest that hydatid fluid-induced autophagy in dendritic cells plays a crucial role in shaping the subsequent T cell responses, which is important for a better understanding of host-parasite interactions in cystic echinococcosis.
Topics: Dendritic Cells; Animals; Echinococcus granulosus; Autophagy; Echinococcosis; T-Lymphocytes; Mice; Lectins, C-Type; Cytokines; Female; Autophagosomes
PubMed: 38817444
DOI: 10.3389/fcimb.2024.1334211 -
Pediatric Research May 2024Preterm infants are susceptible to oxidative stress and prone to respiratory diseases. Autophagy is an important defense mechanism against oxidative-stress-induced cell...
BACKGROUND
Preterm infants are susceptible to oxidative stress and prone to respiratory diseases. Autophagy is an important defense mechanism against oxidative-stress-induced cell damage and involved in lung development and respiratory morbidity. We hypothesized that autophagy marker levels differ between preterm and term infants.
METHODS
In the prospective Basel-Bern Infant Lung Development (BILD) birth cohort we compared cord blood levels of macroautophagy (Beclin-1, LC3B), selective autophagy (p62) and regulation of autophagy (SIRT1) in 64 preterm and 453 term infants.
RESULTS
Beclin-1 and LC3B did not differ between preterm and term infants. However, p62 was higher (0.37, 95% confidence interval (CI) 0.05;0.69 in log2-transformed level, p = 0.025, p = 0.050) and SIRT1 lower in preterm infants (-0.55, 95% CI -0.78;-0.31 in log2-transformed level, p < 0.001). Furthermore, p62 decreased (p-value for smoothing function was 0.018) and SIRT1 increased (0.10, 95% CI 0.07;0.13 in log2-transformed level, p < 0.001) with increasing gestational age.
CONCLUSION
Our findings suggest differential levels of key autophagy markers between preterm and term infants. This adds to the knowledge of the sparsely studied field of autophagy mechanisms in preterm infants and might be linked to impaired oxidative stress response, preterm birth, impaired lung development and higher susceptibility to respiratory morbidity in preterm infants.
IMPACT
To the best of our knowledge, this is the first study to investigate autophagy marker levels between human preterm and term infants in a large population-based sample in cord blood plasma This study demonstrates differential levels of key autophagy markers in preterm compared to term infants and an association with gestational age This may be linked to impaired oxidative stress response or developmental aspects and provide bases for future studies investigating the association with respiratory morbidity.
PubMed: 38811718
DOI: 10.1038/s41390-024-03273-6 -
Biochimica Et Biophysica Acta.... Aug 2024Autophagy is a critical conserved cellular process in maintaining cellular homeostasis by clearing and recycling damaged organelles and intracellular components in... (Review)
Review
Autophagy is a critical conserved cellular process in maintaining cellular homeostasis by clearing and recycling damaged organelles and intracellular components in lysosomes and vacuoles. Autophagy plays a vital role in cell survival, bioenergetic homeostasis, organism development, and cell death regulation. Malfunctions in autophagy are associated with various human diseases and health disorders, such as cancers and neurodegenerative diseases. Significant effort has been devoted to autophagy-related research in the context of genes, proteins, diagnosis, etc. In recent years, there has been a surge of studies utilizing state of the art machine learning (ML) tools to analyze and understand the roles of autophagy in various biological processes. We taxonomize ML techniques that are applicable in an autophagy context, comprehensively review existing efforts being taken in this direction, and outline principles to consider in a biomedical context. In recognition of recent groundbreaking advances in the deep-learning community, we discuss new opportunities in interdisciplinary collaborations and seek to engage autophagy and computer science researchers to promote autophagy research with joint efforts.
Topics: Humans; Autophagy; Machine Learning; Animals; Neurodegenerative Diseases; Neoplasms
PubMed: 38801963
DOI: 10.1016/j.bbadis.2024.167263 -
Autophagy Jun 2024The dysregulation of membrane protein expression has been implicated in tumorigenesis and progression, including hepatocellular carcinoma (HCC). In this study, we aimed...
The dysregulation of membrane protein expression has been implicated in tumorigenesis and progression, including hepatocellular carcinoma (HCC). In this study, we aimed to identify membrane proteins that modulate HCC viability. To achieve this, we performed a CRISPR activation screen targeting human genes encoding membrane-associated proteins, revealing TMX2 as a potential driver of HCC cell viability. Gain- and loss-of-function experiments demonstrated that TMX2 promoted growth and tumorigenesis of HCC. Clinically, TMX2 was an independent prognostic factor for HCC patients. It was significantly upregulated in HCC tissues and associated with poor prognosis of HCC patients. Mechanistically, TMX2 was demonstrated to promote macroautophagy/autophagy by facilitating KPNB1 nuclear export and TFEB nuclear import. In addition, TMX2 interacted with VDAC2 and VADC3, assisting in the recruitment of PRKN to defective mitochondria to promote cytoprotective mitophagy during oxidative stress. Most interestingly, HCC cells responded to oxidative stress by upregulating TMX2 expression and cell autophagy. Knockdown of enhanced the anti-tumor effect of lenvatinib. In conclusion, our findings emphasize the pivotal role of TMX2 in driving the HCC cell viability by promoting both autophagy and mitophagy. These results suggest that TMX2 May serve as a prognostic marker and promising therapeutic target for HCC treatment.: CCCP: Carbonyl cyanide 3-chlorophenylhydrazone; Co-IP: co-immunoprecipitation; CRISPR: clustered regularly interspaced short palindromic repeat; ER: endoplasmic reticulum; HCC: hepatocellular carcinoma; KPNB1: karyopherin subunit beta 1; PRKN: parkin RBR E3 ubiquitin protein ligase; ROS: reactive oxygen species; TFEB: transcription factor EB; TMX2: thioredoxin related transmembrane protein 2; VDAC2: voltage dependent anion channel 2; VDAC3: voltage dependent anion channel 3; WB: western blot.
PubMed: 38797513
DOI: 10.1080/15548627.2024.2358732 -
Cell Death & Disease May 2024Macroautophagy (hereafter called autophagy) is an essential physiological process of degradation of organelles and long-lived proteins. The discovery of autosis, a...
Macroautophagy (hereafter called autophagy) is an essential physiological process of degradation of organelles and long-lived proteins. The discovery of autosis, a Na/K-ATPase (ATP1)-dependent type of autophagic cell death with specific morphological and biochemical features, has strongly contributed to the acceptance of a pro-death role of autophagy. However, the occurrence and relevance of autosis in neurons has never been clearly investigated, whereas we previously provided evidence that autophagy mechanisms could be involved in neuronal death in different in vitro and in vivo rodent models of hypoxia-ischemia (HI) and that morphological features of autosis were observed in dying neurons following rat perinatal cerebral HI. In the present study, we demonstrated that neuronal autosis could occur in primary cortical neurons using two different stimulations enhancing autophagy flux and neuronal death: a neurotoxic concentration of Tat-BECN1 (an autophagy-inducing peptide) and a hypoxic/excitotoxic stimulus (mimicking neuronal death induced by cerebral HI). Both stimulations induce autophagic neuronal death (dependent on canonical autophagic genes and independent on apoptotic, necroptotic or ferroptotic pathways) with all morphological and biochemical (ATP1a-dependent) features of autosis. However, we demonstrated that autosis is not dependent on the ubiquitous subunit ATP1a1 in neurons, as in dividing cell types, but on the neuronal specific ATP1a3 subunit. We also provided evidence that, in different in vitro and in vivo models where autosis is induced, ATP1a3-BECN1 interaction is increased and prevented by cardiac glycosides treatment. Interestingly, an increase in ATP1a3-BECN1 interaction is also detected in dying neurons in the autoptic brains of human newborns with severe hypoxic-ischemic encephalopathy (HIE). Altogether, these results suggest that ATP1a3-BECN1-dependent autosis could play an important role in neuronal death in HI conditions, paving the way for the development of new neuroprotective strategies in hypoxic-ischemic conditions including in severe case of human HIE.
Topics: Animals; Humans; Mice; Rats; Autophagic Cell Death; Autophagy; Hypoxia-Ischemia, Brain; Neurons; Sodium-Potassium-Exchanging ATPase
PubMed: 38796484
DOI: 10.1038/s41419-024-06750-2 -
Cell Communication and Signaling : CCS May 2024Aging is a complex and multifaceted process involving a variety of interrelated molecular mechanisms and cellular systems. Phenotypically, the biological aging process... (Review)
Review
Aging is a complex and multifaceted process involving a variety of interrelated molecular mechanisms and cellular systems. Phenotypically, the biological aging process is accompanied by a gradual loss of cellular function and the systemic deterioration of multiple tissues, resulting in susceptibility to aging-related diseases. Emerging evidence suggests that aging is closely associated with telomere attrition, DNA damage, mitochondrial dysfunction, loss of nicotinamide adenine dinucleotide levels, impaired macro-autophagy, stem cell exhaustion, inflammation, loss of protein balance, deregulated nutrient sensing, altered intercellular communication, and dysbiosis. These age-related changes may be alleviated by intervention strategies, such as calorie restriction, improved sleep quality, enhanced physical activity, and targeted longevity genes. In this review, we summarise the key historical progress in the exploration of important causes of aging and anti-aging strategies in recent decades, which provides a basis for further understanding of the reversibility of aging phenotypes, the application prospect of synthetic biotechnology in anti-aging therapy is also prospected.
Topics: Animals; Humans; Aging; Caloric Restriction; DNA Damage; Longevity; Mitochondria; Therapeutics
PubMed: 38790068
DOI: 10.1186/s12964-024-01663-1