Pub Date : 2025-03-05DOI: 10.1080/15548627.2025.2471633
Lei Xu, Yangfan Ye, Wei Gu, Xiao Xu, Nuo Chen, Liuchao Zhang, Wanzhi Cai, Jingming Hu, Tian Wang, Honglu Chao, Yiming Tu, Jing Ji
Alleviating the multiple types of programmed neuronal death caused by mechanical injury has been an impetus for designing neuro-therapeutical approaches after traumatic brain injury (TBI). The aim of this study was to elucidate the potential role of PSMD14 (proteasome 26S subunit, non-ATPase 14) in neuron death and the specific mechanism through which it improves prognosis of TBI patients. Here, we identified differential expression of the PSMD14 protein between the controlled cortical impact (CCI) and sham mouse groups by LC-MS proteomic analysis and found that PSMD14 was significantly upregulated in neurons after brain injury by qPCR and western blot. PSMD14 suppressed stretch-induced neuron PANoptosis and improved motor ability and learning performance after CCI in vivo. Mechanistically, PSMD14 improved PINK1 phosphorylation levels at Thr257 and activated PINK1-mediated mitophagy by deubiquitinating PKM/PKM2 (pyruvate kinase M1/2) to maintain PKM protein stability. PSMD14-induced mitophagy promoted mitochondrial homeostasis to reduced ROS production, and ultimately inhibited the neuron PANoptosis. The upregulation of neuronal PSMD14 after TBI was due to the increase of histone lactation modification level and lactate treatment alleviated neuron PANoptosis via increasing PSMD14 expression. Our findings suggest that PSMD14 could be a potential therapeutic approach for improving the prognosis of TBI patients.Abbreviations: CCI: controlled cortical impact; CQ: chloroquine; DUBs: deubiquitinating enzymes; H3K18la: H3 lysine 18 lactylation; IB: immunoblot; IHC: immunohistochemistry; IP: immunoprecipitation; MLKL: mixed lineage kinase domain like pseudokinase; PI3K: phosphoinositide 3-kinase; PINK1: PTEN induced kinase 1; PKM/PKM2: pyruvate kinase M1/2; PSMD14: proteasome 26S subunit, non-ATPase 14; ROS: reactive oxygen species; RIPK1: receptor interacting serine/threonine kinase 1; RIPK3: receptor interacting serine/threonine kinase 3; TBI: traumatic brain injury.
{"title":"Histone lactylation stimulated upregulation of PSMD14 alleviates neuron PANoptosis through deubiquitinating PKM2 to activate PINK1-mediated mitophagy after traumatic brain injury.","authors":"Lei Xu, Yangfan Ye, Wei Gu, Xiao Xu, Nuo Chen, Liuchao Zhang, Wanzhi Cai, Jingming Hu, Tian Wang, Honglu Chao, Yiming Tu, Jing Ji","doi":"10.1080/15548627.2025.2471633","DOIUrl":"10.1080/15548627.2025.2471633","url":null,"abstract":"<p><p>Alleviating the multiple types of programmed neuronal death caused by mechanical injury has been an impetus for designing neuro-therapeutical approaches after traumatic brain injury (TBI). The aim of this study was to elucidate the potential role of PSMD14 (proteasome 26S subunit, non-ATPase 14) in neuron death and the specific mechanism through which it improves prognosis of TBI patients. Here, we identified differential expression of the PSMD14 protein between the controlled cortical impact (CCI) and sham mouse groups by LC-MS proteomic analysis and found that PSMD14 was significantly upregulated in neurons after brain injury by qPCR and western blot. PSMD14 suppressed stretch-induced neuron PANoptosis and improved motor ability and learning performance after CCI in vivo. Mechanistically, PSMD14 improved PINK1 phosphorylation levels at Thr257 and activated PINK1-mediated mitophagy by deubiquitinating PKM/PKM2 (pyruvate kinase M1/2) to maintain PKM protein stability. PSMD14-induced mitophagy promoted mitochondrial homeostasis to reduced ROS production, and ultimately inhibited the neuron PANoptosis. The upregulation of neuronal PSMD14 after TBI was due to the increase of histone lactation modification level and lactate treatment alleviated neuron PANoptosis via increasing PSMD14 expression. Our findings suggest that PSMD14 could be a potential therapeutic approach for improving the prognosis of TBI patients.<b>Abbreviations:</b> CCI: controlled cortical impact; CQ: chloroquine; DUBs: deubiquitinating enzymes; H3K18la: H3 lysine 18 lactylation; IB: immunoblot; IHC: immunohistochemistry; IP: immunoprecipitation; MLKL: mixed lineage kinase domain like pseudokinase; PI3K: phosphoinositide 3-kinase; PINK1: PTEN induced kinase 1; PKM/PKM2: pyruvate kinase M1/2; PSMD14: proteasome 26S subunit, non-ATPase 14; ROS: reactive oxygen species; RIPK1: receptor interacting serine/threonine kinase 1; RIPK3: receptor interacting serine/threonine kinase 3; TBI: traumatic brain injury.</p>","PeriodicalId":93893,"journal":{"name":"Autophagy","volume":" ","pages":"1-19"},"PeriodicalIF":0.0,"publicationDate":"2025-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143506722","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-03-04DOI: 10.1080/15548627.2025.2469315
Qiyu Tang, Keyi Tang, Greg R Markby, Maciej Parys, Kanchan Phadwal, Vicky E MacRae, Brendan M Corcoran
<p><p>Myxomatous mitral valve degeneration (MMVD) is one of the most important age-dependent degenerative heart valve disorders in both humans and dogs. It is characterized by the aberrant remodeling of extracellular matrix (ECM), regulated by senescent myofibroblasts (aVICs) transitioning from quiescent valve interstitial cells (qVICs), primarily under TGFB1/TGF-β1 control. In the present study, we found senescent aVICs exhibited impaired macroautophagy/autophagy as evidenced by compromised autophagy flux and immature autophagosomes. MTOR-dependent autophagy induced by rapamycin and torin-1 attenuated cell senescence and decreased the expression of cyclin-dependent kinase inhibitors (CDKIs) CDKN2A/p16<sup>INK4A</sup> and CDKN1A/p21<sup>CIP1</sup>. Furthermore, induction of autophagy in aVICs by <i>ATG</i> (autophagy related) gene overexpression restored autophagy flux, with a concomitant reduction in CDKN1A and CDKN2A expression and senescence-associated secretory phenotype (SASP). Conversely, autophagy deficiency induced CDKN1A and CDKN2A accumulation and SASP, whereas ATG re-expression alleviated senescent phenotypic transformation. Notably, CDKN1A and CDKN2A localized to autophagosomes and lysosomes following MTOR antagonism or MG132 treatment. SQSTM1/p62 was identified as the autophagy receptor to selectively sequester CDKN1A and CDKN2A cargoes for autophagic degradation. Our findings are the first demonstration that CDKN1A and CDKN2A are degraded through SQSTM1-mediated selective autophagy, independent of the ubiquitin-proteasome pathway. These data will inform development of therapeutic strategies for the treatment of canine and human MMVD, and for the treatment of Alzheimer disease, Parkinson disease and other age-related degenerative disorders.<b>Abbreviations</b>: ACTA2/α-SMA: actin alpha 2, smooth muscle; AKT: AKT serine/threonine kinase; aVICs: activated valve interstitial cells; ATG: autophagy related; baf-A1: bafilomycin A<sub>1</sub>; BrdU, bromodeoxyuridine; BSA: bovine serum albumin; CDKIs, cyclin-dependent kinase inhibitors; CDKN1A/p21: cyclin dependent kinase inhibitor 1A; CDKN2A/p16: cyclin dependent kinase inhibitor 2A; co-IP: co-immunoprecipitation; DMSO: dimethylsulfoxide; ECM, extracellular matrix; EIF4EBP1: eukaryotic translation initiation factor 4E binding protein 1; eGFP: green fluorescent protein; ELISA: enzyme-linked immunosorbent assay; HEK-293T, human embryonic kidney 293T; HRP: horseradish peroxidase; KO: knockout; MAP1LC3/LC3: microtubule associated protein 1 light chain 3; LIR: MAP1LC3/LC3-interacting region; MFS: Marfan syndrome; MKI67/Ki-67: marker of proliferation Ki-67; MMVD: myxomatous mitral valve degeneration; MTOR: mechanistic target of rapamycin kinase; MTORC: MTOR complex; OE: overexpression; PBST, phosphate-buffered saline with 0.1% Tween-20; PCNA: proliferating cell nuclear antigen; PIK3CA/PI3K: phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit alpha; PLA: proximity ligation assays; PS
{"title":"Autophagy regulates cellular senescence by mediating the degradation of CDKN1A/p21 and CDKN2A/p16 through SQSTM1/p62-mediated selective autophagy in myxomatous mitral valve degeneration.","authors":"Qiyu Tang, Keyi Tang, Greg R Markby, Maciej Parys, Kanchan Phadwal, Vicky E MacRae, Brendan M Corcoran","doi":"10.1080/15548627.2025.2469315","DOIUrl":"10.1080/15548627.2025.2469315","url":null,"abstract":"<p><p>Myxomatous mitral valve degeneration (MMVD) is one of the most important age-dependent degenerative heart valve disorders in both humans and dogs. It is characterized by the aberrant remodeling of extracellular matrix (ECM), regulated by senescent myofibroblasts (aVICs) transitioning from quiescent valve interstitial cells (qVICs), primarily under TGFB1/TGF-β1 control. In the present study, we found senescent aVICs exhibited impaired macroautophagy/autophagy as evidenced by compromised autophagy flux and immature autophagosomes. MTOR-dependent autophagy induced by rapamycin and torin-1 attenuated cell senescence and decreased the expression of cyclin-dependent kinase inhibitors (CDKIs) CDKN2A/p16<sup>INK4A</sup> and CDKN1A/p21<sup>CIP1</sup>. Furthermore, induction of autophagy in aVICs by <i>ATG</i> (autophagy related) gene overexpression restored autophagy flux, with a concomitant reduction in CDKN1A and CDKN2A expression and senescence-associated secretory phenotype (SASP). Conversely, autophagy deficiency induced CDKN1A and CDKN2A accumulation and SASP, whereas ATG re-expression alleviated senescent phenotypic transformation. Notably, CDKN1A and CDKN2A localized to autophagosomes and lysosomes following MTOR antagonism or MG132 treatment. SQSTM1/p62 was identified as the autophagy receptor to selectively sequester CDKN1A and CDKN2A cargoes for autophagic degradation. Our findings are the first demonstration that CDKN1A and CDKN2A are degraded through SQSTM1-mediated selective autophagy, independent of the ubiquitin-proteasome pathway. These data will inform development of therapeutic strategies for the treatment of canine and human MMVD, and for the treatment of Alzheimer disease, Parkinson disease and other age-related degenerative disorders.<b>Abbreviations</b>: ACTA2/α-SMA: actin alpha 2, smooth muscle; AKT: AKT serine/threonine kinase; aVICs: activated valve interstitial cells; ATG: autophagy related; baf-A1: bafilomycin A<sub>1</sub>; BrdU, bromodeoxyuridine; BSA: bovine serum albumin; CDKIs, cyclin-dependent kinase inhibitors; CDKN1A/p21: cyclin dependent kinase inhibitor 1A; CDKN2A/p16: cyclin dependent kinase inhibitor 2A; co-IP: co-immunoprecipitation; DMSO: dimethylsulfoxide; ECM, extracellular matrix; EIF4EBP1: eukaryotic translation initiation factor 4E binding protein 1; eGFP: green fluorescent protein; ELISA: enzyme-linked immunosorbent assay; HEK-293T, human embryonic kidney 293T; HRP: horseradish peroxidase; KO: knockout; MAP1LC3/LC3: microtubule associated protein 1 light chain 3; LIR: MAP1LC3/LC3-interacting region; MFS: Marfan syndrome; MKI67/Ki-67: marker of proliferation Ki-67; MMVD: myxomatous mitral valve degeneration; MTOR: mechanistic target of rapamycin kinase; MTORC: MTOR complex; OE: overexpression; PBST, phosphate-buffered saline with 0.1% Tween-20; PCNA: proliferating cell nuclear antigen; PIK3CA/PI3K: phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit alpha; PLA: proximity ligation assays; PS","PeriodicalId":93893,"journal":{"name":"Autophagy","volume":" ","pages":"1-23"},"PeriodicalIF":0.0,"publicationDate":"2025-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143484986","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-03-04DOI: 10.1080/15548627.2025.2469189
Yi Zhang, Yingcong Chen, Choufei Wu, Zhengyi Cai, Weijing Yao, Huan Yang, Juan Song, Xiankuan Xie, Liqin Zhang, Cong Yi
Macroautophagy/autophagy is an evolutionarily conserved intracellular degradation pathway that relies on vacuoles or lysosomes. Over 40 ATG genes have been identified in yeast cells as participants in various types of autophagy, although these genes are non-essential. While some essential genes involved in autophagy have been identified using temperature-sensitive yeast strains, systematic research on essential genes in autophagy remains lacking. To address this, we established an essential protein conditional degradation library using the auxin-inducible degron (AID) system. By introducing the GFP-Atg8 plasmid, we identified 29 essential yeast genes involved in autophagy, 19 of which had not been previously recognized. In summary, the yeast essential protein conditional degradation library we constructed will serve as a valuable resource for systematically investigating the roles of essential genes in autophagy and other biological functions.Abbreviation: AID: auxin-inducible degron; ALP: alkaline phosphatase; ATG: autophagy related; CSG: constitutive slow growth; DAmP: Decreased Abundance by mRNA Perturbation; GFP: green fluorescent protein; MMS: methyl methanesulfonate; ORF: open reading frame; PAS: phagophore assembly site; PCR: polymerase chain reaction; SD-G: glucose starvation medium; SD-N: nitrogen starvation medium; TOR: target of rapamycin kinase; YGRC: yeast genetic resource center; YPD: yeast extract peptone dextrose.
{"title":"Establishment of a yeast essential protein conditional-degradation library and screening for autophagy-regulating genes.","authors":"Yi Zhang, Yingcong Chen, Choufei Wu, Zhengyi Cai, Weijing Yao, Huan Yang, Juan Song, Xiankuan Xie, Liqin Zhang, Cong Yi","doi":"10.1080/15548627.2025.2469189","DOIUrl":"10.1080/15548627.2025.2469189","url":null,"abstract":"<p><p>Macroautophagy/autophagy is an evolutionarily conserved intracellular degradation pathway that relies on vacuoles or lysosomes. Over 40 <i>ATG</i> genes have been identified in yeast cells as participants in various types of autophagy, although these genes are non-essential. While some essential genes involved in autophagy have been identified using temperature-sensitive yeast strains, systematic research on essential genes in autophagy remains lacking. To address this, we established an essential protein conditional degradation library using the auxin-inducible degron (AID) system. By introducing the GFP-Atg8 plasmid, we identified 29 essential yeast genes involved in autophagy, 19 of which had not been previously recognized. In summary, the yeast essential protein conditional degradation library we constructed will serve as a valuable resource for systematically investigating the roles of essential genes in autophagy and other biological functions.<b>Abbreviation:</b> AID: auxin-inducible degron; ALP: alkaline phosphatase; ATG: autophagy related; CSG: constitutive slow growth; DAmP: Decreased Abundance by mRNA Perturbation; GFP: green fluorescent protein; MMS: methyl methanesulfonate; ORF: open reading frame; PAS: phagophore assembly site; PCR: polymerase chain reaction; SD-G: glucose starvation medium; SD-N: nitrogen starvation medium; TOR: target of rapamycin kinase; YGRC: yeast genetic resource center; YPD: yeast extract peptone dextrose.</p>","PeriodicalId":93893,"journal":{"name":"Autophagy","volume":" ","pages":"1-13"},"PeriodicalIF":0.0,"publicationDate":"2025-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143484987","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The occurrence of necrosis during Mycobacterium bovis (M. bovis) infection is regarded as harmful to the host because it promotes the spread of M. bovis. Ferroptosis is a controlled type of cell death that occurs when there is an excessive buildup of both free iron and harmful lipid peroxides. Here, we demonstrate that the mammalian cell entry (Mce) 4 family protein Mb3523c triggers ferroptosis to promote M. bovis pathogenicity and dissemination. Mechanistically, Mb3523c, through its Y237 and G241 site, interacts with host HSP90 protein to stabilize the LAMP2A on the lysosome to promote the chaperone-mediated autophagy (CMA) pathway. Then, GPX4 is delivered to lysosomes for destruction via the CMA pathway, eventually inducing ferroptosis to promote M. bovis transmission. In summary, our findings offer novel insights into the molecular mechanisms of pathogen-induced ferroptosis, demonstrating that targeting the GPX4-dependent ferroptosis through blocking the M. bovis Mb3523c-host HSP90 interface represents a potential therapeutic strategy for tuberculosis (TB).Abbreviations: CFU: colony-forming units; CMA: chaperone-mediated autophagy; Co-IP: co-immunoprecipitation; Fer-1: ferrostatin-1; GPX4: glutathione peroxidase 4; HSP90: heat shock protein 90; LDH: lactate dehydrogenase; Mce: mammalian cell entry; MOI: multiplicity of infection; Nec-1: necrostatin-1; PI: propidium iodide; RCD: regulated cell death.
{"title":"<i>Mycobacterium bovis</i> Mb3523c protein regulates host ferroptosis via chaperone-mediated autophagy.","authors":"Haoran Wang, Dingpu Liu, Xin Ge, Yuanzhi Wang, Xiangmei Zhou","doi":"10.1080/15548627.2025.2468139","DOIUrl":"10.1080/15548627.2025.2468139","url":null,"abstract":"<p><p>The occurrence of necrosis during <i>Mycobacterium bovis</i> (<i>M. bovis</i>) infection is regarded as harmful to the host because it promotes the spread of <i>M. bovis</i>. Ferroptosis is a controlled type of cell death that occurs when there is an excessive buildup of both free iron and harmful lipid peroxides. Here, we demonstrate that the mammalian cell entry (Mce) 4 family protein Mb3523c triggers ferroptosis to promote <i>M. bovis</i> pathogenicity and dissemination. Mechanistically, Mb3523c, through its Y237 and G241 site, interacts with host HSP90 protein to stabilize the LAMP2A on the lysosome to promote the chaperone-mediated autophagy (CMA) pathway. Then, GPX4 is delivered to lysosomes for destruction via the CMA pathway, eventually inducing ferroptosis to promote <i>M. bovis</i> transmission. In summary, our findings offer novel insights into the molecular mechanisms of pathogen-induced ferroptosis, demonstrating that targeting the GPX4-dependent ferroptosis through blocking the <i>M. bovis</i> Mb3523c-host HSP90 interface represents a potential therapeutic strategy for tuberculosis (TB).<b>Abbreviations</b>: CFU: colony-forming units; CMA: chaperone-mediated autophagy; Co-IP: co-immunoprecipitation; Fer-1: ferrostatin-1; GPX4: glutathione peroxidase 4; HSP90: heat shock protein 90; LDH: lactate dehydrogenase; Mce: mammalian cell entry; MOI: multiplicity of infection; Nec-1: necrostatin-1; PI: propidium iodide; RCD: regulated cell death.</p>","PeriodicalId":93893,"journal":{"name":"Autophagy","volume":" ","pages":"1-18"},"PeriodicalIF":0.0,"publicationDate":"2025-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143451313","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-03-03DOI: 10.1080/15548627.2025.2471736
Ruoxi Zhang, Chunhua Yu, Herbert J Zeh, Guido Kroemer, Daniel J Klionsky, Daolin Tang, Rui Kang
The activation of STING1 can lead to the production and secretion of cytokines, initiating antitumor immunity. Here, we screened an ion channel ligand library and identified tetrandrine, a bis-benzylisoquinoline alkaloid, as an immunological adjuvant that enhances antitumor immunity by preventing the autophagic degradation of the STING1 protein. This tetrandrine effect is independent of its known function as a calcium or potassium channel blocker. Instead, tetrandrine inhibits lysosomal function, impairing cathepsin maturation, and autophagic degradation. Proteomic analysis of lysosomes identified TAX1BP1 as a novel autophagic receptor for the proteolysis of STING1. TAX1BP1 recognizes STING1 through the physical interaction of its coiled-coil domain with the cyclic dinucleotide binding domain of STING1. Systematic mutation of lysine (K) residues revealed that K63-ubiquitination of STING1 at the K224 site ignites TAX1BP1-dependent STING1 degradation. Combined treatment with tetrandrine and STING1 agonists promotes antitumor immunity by converting "cold" pancreatic cancers into "hot" tumors. This process is associated with enhanced cytokine release and increased infiltration of cytotoxic T-cells into the tumor microenvironment. The antitumor immunity mediated by tetrandrine and STING1 agonists is limited by neutralizing antibodies to the type I interferon receptor or CD8+ T cells. Thus, these findings establish a potential immunotherapeutic strategy against pancreatic cancer by preventing the autophagic degradation of STING1.
{"title":"TAX1BP1-dependent autophagic degradation of STING1 impairs anti-tumor immunity.","authors":"Ruoxi Zhang, Chunhua Yu, Herbert J Zeh, Guido Kroemer, Daniel J Klionsky, Daolin Tang, Rui Kang","doi":"10.1080/15548627.2025.2471736","DOIUrl":"10.1080/15548627.2025.2471736","url":null,"abstract":"<p><p>The activation of STING1 can lead to the production and secretion of cytokines, initiating antitumor immunity. Here, we screened an ion channel ligand library and identified tetrandrine, a bis-benzylisoquinoline alkaloid, as an immunological adjuvant that enhances antitumor immunity by preventing the autophagic degradation of the STING1 protein. This tetrandrine effect is independent of its known function as a calcium or potassium channel blocker. Instead, tetrandrine inhibits lysosomal function, impairing cathepsin maturation, and autophagic degradation. Proteomic analysis of lysosomes identified TAX1BP1 as a novel autophagic receptor for the proteolysis of STING1. TAX1BP1 recognizes STING1 through the physical interaction of its coiled-coil domain with the cyclic dinucleotide binding domain of STING1. Systematic mutation of lysine (K) residues revealed that K63-ubiquitination of STING1 at the K224 site ignites TAX1BP1-dependent STING1 degradation. Combined treatment with tetrandrine and STING1 agonists promotes antitumor immunity by converting \"cold\" pancreatic cancers into \"hot\" tumors. This process is associated with enhanced cytokine release and increased infiltration of cytotoxic T-cells into the tumor microenvironment. The antitumor immunity mediated by tetrandrine and STING1 agonists is limited by neutralizing antibodies to the type I interferon receptor or CD8<sup>+</sup> T cells. Thus, these findings establish a potential immunotherapeutic strategy against pancreatic cancer by preventing the autophagic degradation of STING1.</p>","PeriodicalId":93893,"journal":{"name":"Autophagy","volume":" ","pages":"1-22"},"PeriodicalIF":0.0,"publicationDate":"2025-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143506723","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-03-01Epub Date: 2024-12-24DOI: 10.1080/15548627.2024.2443232
Véronique Sauvé, Kalle Gehring
Parkinson disease (PD) is a neurodegenerative disease characterized by the loss of dopaminergic neurons in the substantia nigra, primarily due to mitochondria dysfunction. PRKN (parkin RBR E3 ubiquitin protein ligase) and PINK1 (PTEN induced kinase 1) are linked to early-onset cases of PD and essential for the clearance of damaged mitochondria via selective mitochondrial autophagy (mitophagy). In a recent publication, we detail how a small molecule can activate PRKN mutants that are unable to be phosphorylated, restoring mitophagy in cellular assays. These findings offer hope for the design of therapeutic drugs for some forms of PD.
{"title":"A molecular glue for PRKN/parkin.","authors":"Véronique Sauvé, Kalle Gehring","doi":"10.1080/15548627.2024.2443232","DOIUrl":"10.1080/15548627.2024.2443232","url":null,"abstract":"<p><p>Parkinson disease (PD) is a neurodegenerative disease characterized by the loss of dopaminergic neurons in the <i>substantia nigra</i>, primarily due to mitochondria dysfunction. PRKN (parkin RBR E3 ubiquitin protein ligase) and PINK1 (PTEN induced kinase 1) are linked to early-onset cases of PD and essential for the clearance of damaged mitochondria via selective mitochondrial autophagy (mitophagy). In a recent publication, we detail how a small molecule can activate PRKN mutants that are unable to be phosphorylated, restoring mitophagy in cellular assays. These findings offer hope for the design of therapeutic drugs for some forms of PD.</p>","PeriodicalId":93893,"journal":{"name":"Autophagy","volume":" ","pages":"689-690"},"PeriodicalIF":0.0,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11849950/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142855868","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-03-01Epub Date: 2025-01-05DOI: 10.1080/15548627.2024.2447207
Katrina F Cooper
Macroautophagy is a catabolic process that maintains cellular homeostasis by recycling intracellular material through the use of double-membrane vesicles called autophagosomes. In turn, autophagosomes fuse with vacuoles (in yeast and plants) or lysosomes (in metazoans), where resident hydrolases degrade the cargo. Given the conservation of autophagy, Saccharomyces cerevisiae is a valuable model organism for deciphering molecular details that define macroautophagy pathways. In yeast, macroautophagic pathways fall into two subclasses: selective and nonselective (bulk) autophagy. Bulk autophagy is predominantly upregulated following TORC1 inhibition, triggered by nutrient stress, and degrades superfluous random cytosolic proteins and organelles. In contrast, selective autophagy pathways maintain cellular homeostasis when TORC1 is active by degrading damaged organelles and dysfunctional proteins. Here, selective autophagy receptors mediate cargo delivery to the vacuole. Now, two groups have discovered a new hybrid autophagy mechanism, coined cargo hitchhiking autophagy (CHA), that uses autophagic receptor proteins to deliver selected cargo to phagophores built in response to nutrient stress for the random destruction of cytosolic contents. In CHA, various autophagic receptors link their cargos to lipidated Atg8, located on growing phagophores. In addition, the sorting nexin heterodimer Snx4-Atg20 assists in the degradation of cargo during CHA, possibly by aiding the delivery of cytoplasmic cargos to phagophores and/or by delaying the closure of expanding phagophores. This review will outline this new mechanism, also known as Snx4-assisted autophagy, that degrades an assortment of cargos in yeast, including transcription factors, glycogen, and a subset of ribosomal proteins.
{"title":"Cargo hitchhiking autophagy - a hybrid autophagy pathway utilized in yeast.","authors":"Katrina F Cooper","doi":"10.1080/15548627.2024.2447207","DOIUrl":"10.1080/15548627.2024.2447207","url":null,"abstract":"<p><p>Macroautophagy is a catabolic process that maintains cellular homeostasis by recycling intracellular material through the use of double-membrane vesicles called autophagosomes. In turn, autophagosomes fuse with vacuoles (in yeast and plants) or lysosomes (in metazoans), where resident hydrolases degrade the cargo. Given the conservation of autophagy, <i>Saccharomyces cerevisiae</i> is a valuable model organism for deciphering molecular details that define macroautophagy pathways. In yeast, macroautophagic pathways fall into two subclasses: selective and nonselective (bulk) autophagy. Bulk autophagy is predominantly upregulated following TORC1 inhibition, triggered by nutrient stress, and degrades superfluous random cytosolic proteins and organelles. In contrast, selective autophagy pathways maintain cellular homeostasis when TORC1 is active by degrading damaged organelles and dysfunctional proteins. Here, selective autophagy receptors mediate cargo delivery to the vacuole. Now, two groups have discovered a new hybrid autophagy mechanism, coined cargo hitchhiking autophagy (CHA), that uses autophagic receptor proteins to deliver selected cargo to phagophores built in response to nutrient stress for the random destruction of cytosolic contents. In CHA, various autophagic receptors link their cargos to lipidated Atg8, located on growing phagophores. In addition, the sorting nexin heterodimer Snx4-Atg20 assists in the degradation of cargo during CHA, possibly by aiding the delivery of cytoplasmic cargos to phagophores and/or by delaying the closure of expanding phagophores. This review will outline this new mechanism, also known as Snx4-assisted autophagy, that degrades an assortment of cargos in yeast, including transcription factors, glycogen, and a subset of ribosomal proteins.</p>","PeriodicalId":93893,"journal":{"name":"Autophagy","volume":" ","pages":"500-512"},"PeriodicalIF":0.0,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11849947/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142933939","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
DBI/ACBP is a phylogenetically ancient hormone that stimulates appetite and lipo-anabolism. In response to starvation, DBI/ACBP is secreted through a noncanonical, macroautophagy/autophagy-dependent pathway. The physiological hunger reflex involves starvation-induced secretion of DBI/ACBP from multiple cell types. DBI/ACBP concentrations subsequently increase in extracellular fluids to stimulate food intake. Recently, we observed that glucocorticoids, which are endogenous stress hormones as well as anti-inflammatory drugs, upregulate DBI/ACBP expression at the transcriptional level and stimulate autophagy in hepatocytes, thereby causing a surge in circulating DBI/ACBP levels. Prolonged increase in glucocorticoid concentrations causes an extreme form of metabolic syndrome, dubbed "Cushing syndrome", which is characterized by clinical features including hyperphagia, hyperdipsia, dyslipidemia, hyperinsulinemia, insulin resistance, lipodystrophy, visceral adiposity, steatosis, sarcopenia and osteoporosis. Mice and patients with Cushing syndrome exhibit supraphysiological DBI/ACBP plasma levels. Of note, neutralization of extracellular DBI/ACBP protein with antibodies or mutation of the DBI/ACBP receptor (i.e. the GABRG2 subunit of GABR [gamma-aminobutyric acid type A receptor]) renders mice resistant to the induction of Cushing syndrome. Similarly, knockout of Dbi/Acbp in hepatocytes suppresses the corticotherapy-induced surge in plasma DBI/ACBP concentrations and prevents the manifestation of most of the characteristics of Cushing syndrome. We conclude that autophagy-mediated secretion of DBI/ACBP by hepatocytes constitutes a critical step of the pathomechanism of Cushing syndrome. It is tempting to speculate that stress-induced chronic elevations of endogenous glucocorticoids also compromise human health due to the protracted augmentation of circulating DBI/ACBP concentrations.Abbreviations: DBI/ACBP: diazepam binding inhibitor, acyl-CoA binding protein; GABA: gamma-aminobutyric acid; GABAR: gamma-aminobutyric acid type A receptor; GABRG2: gamma-aminobutyric acid type A receptor subunit gamma2.
{"title":"Autophagy-dependent hepatocyte secretion of DBI/ACBP induced by glucocorticoids determines the pathogenesis of Cushing syndrome.","authors":"Hui Pan, Ai-Ling Tian, Fréderic Castinetti, Isabelle Martins, Oliver Kepp, Guido Kroemer","doi":"10.1080/15548627.2024.2437649","DOIUrl":"10.1080/15548627.2024.2437649","url":null,"abstract":"<p><p>DBI/ACBP is a phylogenetically ancient hormone that stimulates appetite and lipo-anabolism. In response to starvation, DBI/ACBP is secreted through a noncanonical, macroautophagy/autophagy-dependent pathway. The physiological hunger reflex involves starvation-induced secretion of DBI/ACBP from multiple cell types. DBI/ACBP concentrations subsequently increase in extracellular fluids to stimulate food intake. Recently, we observed that glucocorticoids, which are endogenous stress hormones as well as anti-inflammatory drugs, upregulate DBI/ACBP expression at the transcriptional level and stimulate autophagy in hepatocytes, thereby causing a surge in circulating DBI/ACBP levels. Prolonged increase in glucocorticoid concentrations causes an extreme form of metabolic syndrome, dubbed \"Cushing syndrome\", which is characterized by clinical features including hyperphagia, hyperdipsia, dyslipidemia, hyperinsulinemia, insulin resistance, lipodystrophy, visceral adiposity, steatosis, sarcopenia and osteoporosis. Mice and patients with Cushing syndrome exhibit supraphysiological DBI/ACBP plasma levels. Of note, neutralization of extracellular DBI/ACBP protein with antibodies or mutation of the DBI/ACBP receptor (i.e. the GABRG2 subunit of GABR [gamma-aminobutyric acid type A receptor]) renders mice resistant to the induction of Cushing syndrome. Similarly, knockout of <i>Dbi/Acbp</i> in hepatocytes suppresses the corticotherapy-induced surge in plasma DBI/ACBP concentrations and prevents the manifestation of most of the characteristics of Cushing syndrome. We conclude that autophagy-mediated secretion of DBI/ACBP by hepatocytes constitutes a critical step of the pathomechanism of Cushing syndrome. It is tempting to speculate that stress-induced chronic elevations of endogenous glucocorticoids also compromise human health due to the protracted augmentation of circulating DBI/ACBP concentrations.<b>Abbreviations</b>: DBI/ACBP: diazepam binding inhibitor, acyl-CoA binding protein; GABA: gamma-aminobutyric acid; GABAR: gamma-aminobutyric acid type A receptor; GABRG2: gamma-aminobutyric acid type A receptor subunit gamma2.</p>","PeriodicalId":93893,"journal":{"name":"Autophagy","volume":" ","pages":"678-680"},"PeriodicalIF":0.0,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11849933/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142814970","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-03-01Epub Date: 2024-07-20DOI: 10.1080/15548627.2024.2379065
Andrea Ravasio, Daniel J Klionsky, Cristina Bertocchi
Recent key technological developments, such as super-resolution microscopy and microfabrication, enabled investigation of biological processes, including macroautophagy/autophagy, with unprecedented spatiotemporal resolution and control over experimental conditions. Such disruptive innovations deepened our capability to provide mechanistic understandings of the autophagic process and its causes. This addendum aims to expand the guidelines on autophagy in three key directions: optical methods enabling visualization of autophagic machinery beyond the diffraction-limited resolution; bioengineering enabling accurate designs and control over experimental conditions; and theoretical advances in mechanobiology connecting autophagy and mechanical processes of the cell. Abbreviation: 3D: three-dimensional; SIM: structured illumination microscopy; STORM: stochastic optical reconstruction microscopy.
{"title":"Integrating bioengineering, super-resolution microscopy and mechanobiology in autophagy research: addendum to the guidelines (4th edition).","authors":"Andrea Ravasio, Daniel J Klionsky, Cristina Bertocchi","doi":"10.1080/15548627.2024.2379065","DOIUrl":"10.1080/15548627.2024.2379065","url":null,"abstract":"<p><p>Recent key technological developments, such as super-resolution microscopy and microfabrication, enabled investigation of biological processes, including macroautophagy/autophagy, with unprecedented spatiotemporal resolution and control over experimental conditions. Such disruptive innovations deepened our capability to provide mechanistic understandings of the autophagic process and its causes. This addendum aims to expand the guidelines on autophagy in three key directions: optical methods enabling visualization of autophagic machinery beyond the diffraction-limited resolution; bioengineering enabling accurate designs and control over experimental conditions; and theoretical advances in mechanobiology connecting autophagy and mechanical processes of the cell. <b>Abbreviation:</b> 3D: three-dimensional; SIM: structured illumination microscopy; STORM: stochastic optical reconstruction microscopy.</p>","PeriodicalId":93893,"journal":{"name":"Autophagy","volume":" ","pages":"674-677"},"PeriodicalIF":0.0,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11849944/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141731696","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Metabolic reprogramming is pivotal in cancer stem cell (CSC) self-renewal. However, the intricate regulatory mechanisms governing the crosstalk between metabolic reprogramming and liver CSCs remain elusive. Here, using a metabolic CRISPR-Cas9 knockout screen, we identify ATP6V1D, a subunit of the vacuolar-type H+-translocating ATPase (V-ATPase), as a key metabolic regulator of hepatocellular carcinoma (HCC) stemness. Elevated ATP6V1D expression correlates with poor clinical outcomes in HCC patients. ATP6V1D knockdown inhibits HCC stemness and malignant progression both in vitro and in vivo. Mechanistically, ATP6V1D enhances HCC stemness and progression by maintaining macroautophagic/autophagic flux. Specifically, ATP6V1D not only promotes lysosomal acidification, but also enhances the interaction between CHMP4B and IST1 to foster ESCRT-III complex assembly, thereby facilitating autophagosome-lysosome fusion to maintain autophagic flux. Moreover, silencing CHMP4B or IST1 attenuates HCC stemness and progression. Notably, low-dose bafilomycin A1 targeting the V-ATPase complex shows promise as a potential therapeutic strategy for HCC. In conclusion, our study highlights the critical role of ATP6V1D in driving HCC stemness and progression via the autophagy-lysosomal pathway, providing novel therapeutic targets and approaches for HCC treatment.Abbreviations: 3-MA: 3-methyladenine; ANT: adjacent normal liver tissues; ATP6V1D: ATPase H+ transporting V1 subunit D; BafA1: bafilomycin A1; CHMP: charged multivesicular body protein; co-IP: co-immunoprecipitation; CSC: cancer stem cell; ESCRT: endosomal sorting complex required for transport; HCC: hepatocellular carcinoma; IF: immunofluorescence; IHC: immunohistochemical; LCSCs: liver cancer stem cells; qRT-PCR: quantitative real time PCR; V-ATPase: vacuolar-type H+- translocating ATPase; WB: western blot.
{"title":"ATP6V1D drives hepatocellular carcinoma stemness and progression via both lysosome acidification-dependent and -independent mechanisms.","authors":"Zhijie Xu, Ruiyang Liu, Haoying Ke, Fuyuan Xu, Pengfei Yang, Weiyu Zhang, Yi Zhan, Zhiju Zhao, Fei Xiao","doi":"10.1080/15548627.2024.2406186","DOIUrl":"10.1080/15548627.2024.2406186","url":null,"abstract":"<p><p>Metabolic reprogramming is pivotal in cancer stem cell (CSC) self-renewal. However, the intricate regulatory mechanisms governing the crosstalk between metabolic reprogramming and liver CSCs remain elusive. Here, using a metabolic CRISPR-Cas9 knockout screen, we identify ATP6V1D, a subunit of the vacuolar-type H<sup>+</sup>-translocating ATPase (V-ATPase), as a key metabolic regulator of hepatocellular carcinoma (HCC) stemness. Elevated ATP6V1D expression correlates with poor clinical outcomes in HCC patients. ATP6V1D knockdown inhibits HCC stemness and malignant progression both <i>in vitro</i> and <i>in vivo</i>. Mechanistically, ATP6V1D enhances HCC stemness and progression by maintaining macroautophagic/autophagic flux. Specifically, ATP6V1D not only promotes lysosomal acidification, but also enhances the interaction between CHMP4B and IST1 to foster ESCRT-III complex assembly, thereby facilitating autophagosome-lysosome fusion to maintain autophagic flux. Moreover, silencing CHMP4B or IST1 attenuates HCC stemness and progression. Notably, low-dose bafilomycin A<sub>1</sub> targeting the V-ATPase complex shows promise as a potential therapeutic strategy for HCC. In conclusion, our study highlights the critical role of ATP6V1D in driving HCC stemness and progression via the autophagy-lysosomal pathway, providing novel therapeutic targets and approaches for HCC treatment.<b>Abbreviations:</b> 3-MA: 3-methyladenine; ANT: adjacent normal liver tissues; ATP6V1D: ATPase H+ transporting V1 subunit D; BafA1: bafilomycin A<sub>1</sub>; CHMP: charged multivesicular body protein; co-IP: co-immunoprecipitation; CSC: cancer stem cell; ESCRT: endosomal sorting complex required for transport; HCC: hepatocellular carcinoma; IF: immunofluorescence; IHC: immunohistochemical; LCSCs: liver cancer stem cells; qRT-PCR: quantitative real time PCR; V-ATPase: vacuolar-type H<sup>+</sup>- translocating ATPase; WB: western blot.</p>","PeriodicalId":93893,"journal":{"name":"Autophagy","volume":" ","pages":"513-529"},"PeriodicalIF":0.0,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11849949/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142334256","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}