AutophagyPub Date : 2024-11-01Epub Date: 2024-07-04DOI: 10.1080/15548627.2024.2367907
Rui Tian, Pengwei Zhao, Xianming Ding, Xinyi Wang, Xiao Jiang, Shuai Chen, Zhijian Cai, Lin Li, She Chen, Wei Liu, Qiming Sun
{"title":"TBC1D4 antagonizes RAB2A-mediated autophagic and endocytic pathways.","authors":"Rui Tian, Pengwei Zhao, Xianming Ding, Xinyi Wang, Xiao Jiang, Shuai Chen, Zhijian Cai, Lin Li, She Chen, Wei Liu, Qiming Sun","doi":"10.1080/15548627.2024.2367907","DOIUrl":"10.1080/15548627.2024.2367907","url":null,"abstract":"<p><p>Macroautophagic/autophagic and endocytic pathways play essential roles in maintaining homeostasis at different levels. It remains poorly understood how both pathways are coordinated and fine-tuned for proper lysosomal degradation of diverse cargoes. We and others recently identified a Golgi-resident RAB GTPase, RAB2A, as a positive regulator that controls both autophagic and endocytic pathways. In the current study, we report that TBC1D4 (TBC1 domain family member 4), a TBC domain-containing protein that plays essential roles in glucose homeostasis, suppresses RAB2A-mediated autophagic and endocytic pathways. TBC1D4 bound to RAB2A through its N-terminal PTB2 domain, which impaired RAB2A-mediated autophagy at the early stage by preventing ULK1 complex activation. During the late stage of autophagy, TBC1D4 impeded the association of RUBCNL/PACER and RAB2A with STX17 on autophagosomes by direct interaction with RUBCNL via its N-terminal PTB1 domain. Disruption of the autophagosomal trimeric complex containing RAB2A, RUBCNL and STX17 resulted in defective HOPS recruitment and eventually abortive autophagosome-lysosome fusion. Furthermore, TBC1D4 inhibited RAB2A-mediated endocytic degradation independent of RUBCNL. Therefore, TBC1D4 and RAB2A form a dual molecular switch to modulate autophagic and endocytic pathways. Importantly, hepatocyte- or adipocyte-specific <i>tbc1d4</i> knockout in mice led to elevated autophagic flux and endocytic degradation and tissue damage. Together, this work establishes TBC1D4 as a critical molecular brake in autophagic and endocytic pathways, providing further mechanistic insights into how these pathways are intertwined both in vitro and in vivo.<b>Abbreviations</b>: ACTB: actin beta; ATG9: autophagy related 9; ATG14: autophagy related 14; ATG16L1: autophagy related 16 like 1; CLEM: correlative light electron microscopy; Ctrl: control; DMSO: dimethyl sulfoxide; EGF: epidermal growth factor; EGFR: epidermal growth factor receptor; FL: full length; GAP: GTPase-activating protein; GFP: green fluorescent protein; HOPS: homotypic fusion and protein sorting; IP: immunoprecipitation; KD: knockdown; KO: knockout; LAMP1: lysosomal associated membrane protein 1; MAP1LC3B/LC3B: microtubule associated protein 1 light chain 3 beta; OE: overexpression; PG: phagophore; PtdIns3K: class III phosphatidylinositol 3-kinase; SLC2A4/GLUT4: solute carrier family 2 member 4; SQSTM1/p62: sequestosome 1; RUBCNL/PACER: rubicon like autophagy enhancer; STX17: syntaxin 17; TAP: tandem affinity purification; TBA: total bile acid; TBC1D4: TBC1 domain family member 4; TUBA1B: tubulin alpha 1b; ULK1: unc-51 like autophagy activating kinase 1; VPS39: VPS39 subunit of HOPS complex; WB: western blot; WT: wild type.</p>","PeriodicalId":93893,"journal":{"name":"Autophagy","volume":" ","pages":"2426-2443"},"PeriodicalIF":0.0,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11572321/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141536102","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}
AutophagyPub Date : 2024-11-01Epub Date: 2024-08-27DOI: 10.1080/15548627.2024.2394291
Tianyuan Liu, Xianrun Pan, Liping Ren, Xiucai Ye, Kai Zheng, Yang Zhang
{"title":"Mapping autophagy-related membrane contact site proteins and complexes with AutoMCS Navigator.","authors":"Tianyuan Liu, Xianrun Pan, Liping Ren, Xiucai Ye, Kai Zheng, Yang Zhang","doi":"10.1080/15548627.2024.2394291","DOIUrl":"10.1080/15548627.2024.2394291","url":null,"abstract":"<p><p>In eukaryotic cells, membrane contact sites (MCSs) mediate interactions and communication between organelles by bringing their membranes into close proximity without fusion. These sites play crucial roles in intracellular transport, signal transduction, and the regulation of organelle functions. In a recent study, we compiled data on MCS proteins and complexes from publications to create the MCSdb database. During data compilation, we discovered that many MCSs, their associated proteins, and complexes are highly relevant to macroautophagy/autophagy. To elucidate the role of MCSs in autophagy, we reorganized the autophagy-related MCS proteins and complexes from MCSdb, creating a data map called AutoMCS Navigator. The current version of this map includes 30 complexes and 84 proteins, covering 13 different MCSs and 7 species. Meanwhile, we embedded a dedicated webpage for AutoMCS Navigator on the MCSdb website. This webpage features an orchestrated visual guide that hierarchically displays MCS proteins and complexes involved in autophagy. In summary, our research has developed a user-friendly visual map for querying, browsing, and visualizing detailed information on autophagy-related MCS proteins and complexes. This tool offers researchers easy access to understand autophagy-related MCS structure, assembly, functions, and therapeutic strategies for related diseases. AutoMCS Navigator is freely available at https://cellknowledge.com.cn/mcsdb/autophagy.html.</p>","PeriodicalId":93893,"journal":{"name":"Autophagy","volume":" ","pages":"2593-2595"},"PeriodicalIF":0.0,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11572202/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142019886","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}
{"title":"Metabolic stress induces a double-positive feedback loop between AMPK and SQSTM1/p62 conferring dual activation of AMPK and NFE2L2/NRF2 to synergize antioxidant defense.","authors":"Eun-Ji Choi, Hyun-Taek Oh, Seon-Hyeong Lee, Chen-Song Zhang, Mengqi Li, Soo-Youl Kim, Sunghyouk Park, Tong-Shin Chang, Byung-Hoon Lee, Sheng-Cai Lin, Sang-Min Jeon","doi":"10.1080/15548627.2024.2374692","DOIUrl":"10.1080/15548627.2024.2374692","url":null,"abstract":"<p><p>Co-occurring mutations in KEAP1 in STK11/LKB1-mutant NSCLC activate NFE2L2/NRF2 to compensate for the loss of STK11-AMPK activity during metabolic adaptation. Characterizing the regulatory crosstalk between the STK11-AMPK and KEAP1-NFE2L2 pathways during metabolic stress is crucial for understanding the implications of co-occurring mutations. Here, we found that metabolic stress increased the expression and phosphorylation of SQSTM1/p62, which is essential for the activation of NFE2L2 and AMPK, synergizing antioxidant defense and tumor growth. The SQSTM1-driven dual activation of NFE2L2 and AMPK was achieved by inducing macroautophagic/autophagic degradation of KEAP1 and facilitating the AXIN-STK11-AMPK complex formation on the lysosomal membrane, respectively. In contrast, the STK11-AMPK activity was also required for metabolic stress-induced expression and phosphorylation of SQSTM1, suggesting a double-positive feedback loop between AMPK and SQSTM1. Mechanistically, SQSTM1 expression was increased by the PPP2/PP2A-dependent dephosphorylation of TFEB and TFE3, which was induced by the lysosomal deacidification caused by low glucose metabolism and AMPK-dependent proton reduction. Furthermore, SQSTM1 phosphorylation was increased by MAP3K7/TAK1, which was activated by ROS and pH-dependent secretion of lysosomal Ca<sup>2+</sup>. Importantly, phosphorylation of SQSTM1 at S24 and S226 was critical for the activation of AMPK and NFE2L2. Notably, the effects caused by metabolic stress were abrogated by the protons provided by lactic acid. Collectively, our data reveal a novel double-positive feedback loop between AMPK and SQSTM1 leading to the dual activation of AMPK and NFE2L2, potentially explaining why co-occurring mutations in STK11 and KEAP1 happen and providing promising therapeutic strategies for lung cancer.<b>Abbreviations</b>: AMPK: AMP-activated protein kinase; BAF1: bafilomycin A<sub>1</sub>; ConA: concanamycin A; DOX: doxycycline; IP: immunoprecipitation; KEAP1: kelch like ECH associated protein 1; LN: low nutrient; MAP3K7/TAK1: mitogen-activated protein kinase kinase kinase 7; MCOLN1/TRPML1: mucolipin TRP cation channel 1; MEFs: mouse embryonic fibroblasts; MTORC1: mechanistic target of rapamycin kinase complex 1; NAC: N-acetylcysteine; NFE2L2/NRF2: NFE2 like bZIP transcription factor 2; NSCLC: non-small cell lung cancer; PRKAA/AMPKα: protein kinase AMP-activated catalytic subunit alpha; PPP2/PP2A: protein phosphatase 2; ROS: reactive oxygen species; PPP3/calcineurin: protein phosphatase 3; RPS6KB1/p70S6K: ribosomal protein S6 kinase B1; SQSTM1/p62: sequestosome 1; STK11/LKB1: serine/threonine kinase 11; TCL: total cell lysate; TFEB: transcription factor EB; TFE3: transcription factor binding to IGHM enhancer 3; V-ATPase: vacuolar-type H<sup>+</sup>-translocating ATPase.</p>","PeriodicalId":93893,"journal":{"name":"Autophagy","volume":" ","pages":"2490-2510"},"PeriodicalIF":0.0,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11572134/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141494594","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}
AutophagyPub Date : 2024-11-01Epub Date: 2024-07-04DOI: 10.1080/15548627.2024.2371717
Diana García-Chávez, Eunice Domínguez-Martín, Laura Kawasaki, Laura Ongay-Larios, Hilario Ruelas-Ramírez, Ariann E Mendoza-Martinez, Juan P Pardo, Soledad Funes, Roberto Coria
{"title":"Prohibitins, Phb1 and Phb2, function as Atg8 receptors to support yeast mitophagy and also play a negative regulatory role in Atg32 processing.","authors":"Diana García-Chávez, Eunice Domínguez-Martín, Laura Kawasaki, Laura Ongay-Larios, Hilario Ruelas-Ramírez, Ariann E Mendoza-Martinez, Juan P Pardo, Soledad Funes, Roberto Coria","doi":"10.1080/15548627.2024.2371717","DOIUrl":"10.1080/15548627.2024.2371717","url":null,"abstract":"<p><p>The prohibitins Phb1 and Phb2 assemble at the mitochondrial inner membrane to form a multi-dimeric complex. These scaffold proteins are highly conserved in eukaryotic cells, from yeast to mammals, and have been implicated in a variety of mitochondrial functions including aging, proliferation, and degenerative and metabolic diseases. In mammals, PHB2 regulates PINK1-PRKN mediated mitophagy by interacting with lipidated MAP1LC3B/LC3B. Despite their high conservation, prohibitins have not been linked to mitophagy in budding yeasts. In this study, we demonstrate that both Phb1 and Phb2 are required to sustain mitophagy in <i>Saccharomyces cerevisiae</i>. Prohibitin-dependent mitophagy requires formation of the Phb1-Phb2 complex and a conserved AIM/LIR-like motif identified in both yeast prohibitins. Furthermore, both Phb1 and Phb2 interact and exhibit mitochondrial colocalization with Atg8. Interestingly, we detected a basal C terminus processing of the mitophagy receptor Atg32 that depends on the presence of the i-AAA Yme1. In the absence of prohibitins this processing is highly enhanced but reverted by the inactivation of the rhomboid protease Pcp1. Together our results revealed a novel role of yeast prohibitins in mitophagy through its interaction with Atg8 and regulating an Atg32 proteolytic event. <b>Abbreviation</b>: AIM/LIR: Atg8-family interacting motif/LC3-interacting region; ANOVA: analysis of variance; ATG/Atg: autophagy related; C terminus/C-terminal: carboxyl terminus/carboxyl-terminal; GFP: green fluorescent protein; HA: human influenza hemagglutinin; Idh1: isocitrate dehydrogenase 1; MAP1C3B/LC3B: microtubule associated protein 1 light chain 3 beta; mCh: mCherry; MIM: mitochondrial inner membrane; MOM: mitochondrial outer membrane; N starvation: nitrogen starvation; N terminus: amino terminus; PARL: presenilin associated rhomboid like; Pcp1: processing of cytochrome c peroxidase 1; PCR: polymerase chain reaction; PGAM5: PGAM family member 5 mitochondrial serine/threonine protein phosphatase; PHBs/Phb: prohibitins; PINK1: PTEN induced kinase 1; PMSF: phenylmethylsulfonyl fluoride; PRKN: parkin RBR E3 ubiquitin protein ligase; SD: synthetic defined medium; SDS: sodium dodecyl sulfate; SMD-N: synthetic defined medium lacking nitrogen; WB: western blot; WT: wild type; Yme1: yeast mitochondrial escape 1; YPD: yeast extract-peptone-dextrose medium; YPLac: yeast extract-peptone-lactate medium.</p>","PeriodicalId":93893,"journal":{"name":"Autophagy","volume":" ","pages":"2478-2489"},"PeriodicalIF":0.0,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11572199/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141536101","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}
AutophagyPub Date : 2024-11-01Epub Date: 2024-06-19DOI: 10.1080/15548627.2024.2367184
Lan Jiang, Haidong He, Yuyan Tang, Jiawei Li, Svetlana Reilly, Hong Xin, Zhiping Li, Hui Cai, Xuemei Zhang
{"title":"Activation of BK channels prevents diabetes-induced osteopenia by regulating mitochondrial Ca<sup>2+</sup> and SLC25A5/ANT2-PINK1-PRKN-mediated mitophagy.","authors":"Lan Jiang, Haidong He, Yuyan Tang, Jiawei Li, Svetlana Reilly, Hong Xin, Zhiping Li, Hui Cai, Xuemei Zhang","doi":"10.1080/15548627.2024.2367184","DOIUrl":"10.1080/15548627.2024.2367184","url":null,"abstract":"<p><p>Osteopenia and osteoporosis are among the most common metabolic bone diseases and represent major public health problems, with sufferers having an increased fracture risk. Diabetes is one of the most common diseases contributing to osteopenia and osteoporosis. However, the mechanisms underlying diabetes-induced osteopenia and osteoporosis remain unclear. Bone reconstruction, including bone formation and absorption, is a dynamic process. Large-conductance Ca<sup>2+</sup>-activated K<sup>+</sup> channels (BK channels) regulate the function of bone marrow-derived mesenchymal stem cells, osteoblasts, and osteoclasts. Our previous studies revealed the relationship between BK channels and the function of osteoblasts via various pathways under physiological conditions. In this study, we reported a decrease in the expression of BK channels in mice with diabetes-induced osteopenia. BK deficiency enhanced mitochondrial Ca<sup>2+</sup> and activated classical PINK1 (PTEN induced putative kinase 1)-PRKN/Parkin (parkin RBR E3 ubiquitin protein ligase)-dependent mitophagy, whereas the upregulation of BK channels inhibited mitophagy in osteoblasts. Moreover, SLC25A5/ANT2 (solute carrier family 25 (mitochondrial carrier, adenine nucleotide translocator), member 5), a critical inner mitochondrial membrane protein participating in PINK1-PRKN-dependent mitophagy, was also regulated by BK channels. Overall, these data identified a novel role of BK channels in regulating mitophagy in osteoblasts, which might be a potential target for diabetes-induced bone diseases.<b>Abbreviations</b>: AGE, advanced glycation end products; Baf A1, bafilomycin A<sub>1</sub>; BK channels, big-conductance Ca<sup>2+</sup>-activated K<sup>+</sup> channels; BMSCs, bone marrow-derived mesenchymal stem cells; BSA, bovine serum albumin; FBG, fasting blood glucose; IMM, inner mitochondrial membrane; ITPR1, inositol 1,4,5-trisphosphate receptor 1; MAM, mitochondria-associated ER membrane; OMM, outer mitochondrial membrane; PINK1, PTEN induced putative kinase 1; PPID/CyP-D, peptidylprolyl isomerase D (cyclophilin D); PRKN/PARK2, parkin RBR E3 ubiquitin protein ligase; ROS, reactive oxygen species; SLC25A5/ANT2, solute carrier family 25 (mitochondrial carrier, adenine nucleotide translocator), member 5; STZ, streptozotocin.</p>","PeriodicalId":93893,"journal":{"name":"Autophagy","volume":" ","pages":"2388-2404"},"PeriodicalIF":0.0,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11572260/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141319256","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}
AutophagyPub Date : 2024-11-01Epub Date: 2024-10-10DOI: 10.1080/15548627.2024.2406127
Ge Yu, Daniel J Klionsky
{"title":"<i>In vitro</i> and <i>in vivo</i> reconstitution systems reveal the membrane remodeling ability of LC3B and ATG16L1 to form phagophore-like membrane cups.","authors":"Ge Yu, Daniel J Klionsky","doi":"10.1080/15548627.2024.2406127","DOIUrl":"10.1080/15548627.2024.2406127","url":null,"abstract":"<p><p>Macroautophagy/autophagy is a conserved pathway allowing the cell to clear and recycle unwanted materials. While decades of research have revealed molecular players and their hierarchical relationships in autophagy, the detailed mechanism by which these molecules function remains largely unknown. In a recent study, Jagan et al. revealed the membrane remodeling ability of two important proteins, MAP1LC3B/LC3B and ATG16L1, in autophagy. LC3B and the ATG12-ATG5-ATG16L1 complex function synergically to induce the formation of phagophore-like membrane cups on membranes both <i>in vitro</i> and <i>in vivo</i>. In addition, the authors showed that the recently characterized C-terminal membrane-binding domain of ATG16L1 is required for the cup formation and the subsequent transition to autophagic vesicles. Together this research provides more insight into the molecular function of LC3B and ATG16L1, as well as a possible mechanism for phagophore biogenesis.</p>","PeriodicalId":93893,"journal":{"name":"Autophagy","volume":" ","pages":"2359-2360"},"PeriodicalIF":0.0,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11572233/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142395878","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}
AutophagyPub Date : 2024-11-01Epub Date: 2024-08-04DOI: 10.1080/15548627.2024.2384349
Jiyoung Choi, Haeun Jang, Zhao Xuan, Daehun Park
{"title":"Emerging roles of ATG9/ATG9A in autophagy: implications for cell and neurobiology.","authors":"Jiyoung Choi, Haeun Jang, Zhao Xuan, Daehun Park","doi":"10.1080/15548627.2024.2384349","DOIUrl":"10.1080/15548627.2024.2384349","url":null,"abstract":"<p><p>Atg9, the only transmembrane protein among many autophagy-related proteins, was first identified in the year 2000 in yeast. Two homologs of Atg9, ATG9A and ATG9B, have been found in mammals. While ATG9B shows a tissue-specific expression pattern, such as in the placenta and pituitary gland, ATG9A is ubiquitously expressed. Additionally, ATG9A deficiency leads to severe defects not only at the molecular and cellular levels but also at the organismal level, suggesting key and fundamental roles for ATG9A. The subcellular localization of ATG9A on small vesicles and its functional relevance to autophagy have suggested a potential role for ATG9A in the lipid supply during autophagosome biogenesis. Nevertheless, the precise role of ATG9A in the autophagic process has remained a long-standing mystery, especially in neurons. Recent findings, however, including structural, proteomic, and biochemical analyses, have provided new insights into its function in the expansion of the phagophore membrane. In this review, we aim to understand various aspects of ATG9 (in invertebrates and plants)/ATG9A (in mammals), including its localization, trafficking, and other functions, in nonneuronal cells and neurons by comparing recent discoveries related to ATG9/ATG9A and proposing directions for future research.<b>Abbreviation</b>: AP-4: adaptor protein complex 4; ATG: autophagy related; cKO: conditional knockout; CLA-1: CLArinet (functional homolog of cytomatrix at the active zone proteins piccolo and fife); cryo-EM: cryogenic electron microscopy; ER: endoplasmic reticulum; KO: knockout; PAS: phagophore assembly site; PtdIns3K: class III phosphatidylinositol 3-kinase; PtdIns3P: phosphatidylinositol-3-phosphate; RB1CC1/FIP200: RB1 inducible coiled-coil 1; SV: synaptic vesicle; TGN: trans-Golgi network; ULK: unc-51 like autophagy activating kinase; WIPI2: WD repeat domain, phosphoinositide interacting 2.</p>","PeriodicalId":93893,"journal":{"name":"Autophagy","volume":" ","pages":"2373-2387"},"PeriodicalIF":0.0,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11572220/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141891250","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}
{"title":"CCDC50 mediates the clearance of protein aggregates to prevent cellular proteotoxicity.","authors":"Yu Ye, Penghui Jia, Jiafan Miao, Yicheng Wang, Zibo Li, Yuxin Lin, Miao He, Shurui Liu, Bi-Rong Zheng, Junyu Wu, Ji'an Pan, Chun-Mei Li, Panpan Hou, Deyin Guo","doi":"10.1080/15548627.2024.2367183","DOIUrl":"10.1080/15548627.2024.2367183","url":null,"abstract":"<p><p>Protein aggregation caused by the disruption of proteostasis will lead to cellular cytotoxicity and even cell death, which is implicated in multiple neurodegenerative diseases. The elimination of aggregated proteins is mediated by selective macroautophagy receptors, which is termed aggrephagy. However, the identity and redundancy of aggrephagy receptors in recognizing substrates remain largely unexplored. Here, we find that CCDC50, a highly expressed autophagy receptor in brain, is recruited to proteotoxic stresses-induced polyubiquitinated protein aggregates and ectopically expressed aggregation-prone proteins. CCDC50 recognizes and further clears these cytotoxic aggregates through autophagy. The ectopic expression of CCDC50 increases the tolerance to stress-induced proteotoxicity and hence improved cell survival in neuron cells, whereas CCDC50 deficiency caused accumulation of lipid deposits and polyubiquitinated protein conjugates in the brain of one-year-old mice. Our study illustrates how aggrephagy receptor CCDC50 combats proteotoxic stress for the benefit of neuronal cell survival, thus suggesting a protective role in neurotoxic proteinopathy.<b>Abbreviations</b>: AD: Alzheimer disease; ALS: amyotrophic lateral sclerosis; ATG5: autophagy related 5; BODIPY: boron-dipyrromethene; CASP3: caspase 3; CCDC50: coiled-coil domain containing 50; CCT2: chaperonin containing TCP1 subunit 2; CHX: cycloheximide; CQ: chloroquine; CRISPR: clustered regulatory interspaced short palindromic repeat; Cas9: CRISPR-associated system 9; DAPI: 4',6-diamidino-2-phenylindole; FK2: Anti-ubiquitinylated proteins antibody, clone FK2; FUS: FUS RNA binding protein; GFP: green fluorescent protein; HD: Huntington disease; HTT: huntingtin; KEGG: Kyoto Encyclopedia of Genes and Genomes; LDS: LIR-docking site; LIR: LC3-interacting region; MAP1LC3/LC3: microtubule associated protein 1 light chain 3; MAPT/tau: microtubule associated protein tau; MIU: motif interacting with ubiquitin; NBR1: NBR1, autophagy cargo receptor; OPTN: optineurin; PD: Parkinson disease; PI: propidium iodide; ROS: reactive oxygen species; SOD1: superoxide dismutase 1; SQSTM1/p62: sequestosome 1; TAX1BP1: Tax1 binding protein 1; Ub: ubiquitin; UDS: UIM-docking site; UIM: ubiquitin interacting motif; UPS: ubiquitin-proteasome system.</p>","PeriodicalId":93893,"journal":{"name":"Autophagy","volume":" ","pages":"2529-2539"},"PeriodicalIF":0.0,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11572255/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141312513","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}
AutophagyPub Date : 2024-11-01Epub Date: 2024-07-10DOI: 10.1080/15548627.2024.2371708
Nitin Sai Beesabathuni, Matthew W Kenaston, Ritika Gangaraju, Neil Alvin B Adia, Vardhan Peddamallu, Priya S Shah
{"title":"Let's talk about flux: the rising potential of autophagy rate measurements in disease.","authors":"Nitin Sai Beesabathuni, Matthew W Kenaston, Ritika Gangaraju, Neil Alvin B Adia, Vardhan Peddamallu, Priya S Shah","doi":"10.1080/15548627.2024.2371708","DOIUrl":"10.1080/15548627.2024.2371708","url":null,"abstract":"<p><p>Macroautophagy/autophagy is increasingly implicated in a variety of diseases, making it an attractive therapeutic target. However, many aspects of autophagy are not fully understood and its impact on many diseases remains debatable and context-specific. The lack of systematic and dynamic measurements in these cases is a key reason for this ambiguity. In recent years, Loos et al. 2014 and Beesabathuni et al. 2022 developed methods to quantitatively measure autophagy holistically. In this commentary, we pose some of the unresolved biological questions regarding autophagy and consider how quantitative measurements may address them. While the applications are ever-expanding, we provide specific use cases in cancer, virus infection, and mechanistic screening. We address how the rate measurements themselves are central to developing cancer therapies and present ways in which these tools can be leveraged to dissect the complexities of virus-autophagy interactions. Screening methods can be combined with rate measurements to mechanistically decipher the labyrinth of autophagy regulation in cancer and virus infection. Taken together, these approaches have the potential to illuminate the underlying mechanisms of various diseases.<b>Abbreviation</b> MAP1LC3/LC3: microtubule-associated protein 1 light chain 3; R<sub>1</sub>: rate of autophagosome formation; R<sub>2</sub>: rate of autophagosome-lysosome fusion; R<sub>3</sub>: rate of autolysosome turnover.</p>","PeriodicalId":93893,"journal":{"name":"Autophagy","volume":" ","pages":"2574-2580"},"PeriodicalIF":0.0,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11572197/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141565338","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}