Autophagy
·
2024
·
IF 14.6
Zhigang Zhang,Shuai Chen,Shirui Jun,Xirong Xu,Yuchuan Hong,Xifei Yang,Liangyu Zou,You-Qiang Song,Yu Chen,Jie Tu
Individuals with genetic elimination of MLKL (mixed lineage kinase domain like pseudokinase) exhibit an increased susceptibility to neurodegenerative diseases like Alzheimer disease (AD). However, the mechanism is not yet fully understood. Here, we observed significant compromise in macroautophagy/autophagy in the brains of mlkl knockout (KO) mice, as evidenced by the downregulation of BECN1/Beclin1 and ULK1 (unc-51 like autophagy activating kinase 1). We identified UBA52 (ubiquitin A-52 residue ribosomal protein fusion product 1) as the binding partner of MLKL under physiological conditions. Loss of Mlkl induced a decrease in ubiquitin levels by preventing UBA52 cleavage. Furthermore, we demonstrated that the deubiquitinase (DUB) USP7 (ubiquitin specific peptidase 7) mediates the processing of UBA52, which is regulated by MLKL. Moreover, our results indicated that the reduction of BECN1 and ULK1 upon Mlkl loss is attributed to a decrease in their lysine 63 (K63)-linked polyubiquitination. Additionally, single-nucleus RNA sequencing revealed that the loss of Mlkl resulted in the disruption of multiple neurodegenerative disease-related pathways, including those associated with AD. These results were consistent with the observation of cognitive impairment in mlkl KO mice and exacerbation of AD pathologies in an AD mouse model with mlkl deletion. Taken together, our findings demonstrate that MLKL-USP7-UBA52 signaling is required for autophagy in brain through maintaining ubiquitin homeostasis, and highlight the contribution of Mlkl loss-induced ubiquitin deficits to the development of neurodegeneration. Thus, the maintenance of adequate levels of ubiquitin may provide a novel perspective to protect individuals from multiple neurodegenerative diseases through regulating autophagy.Abbreviations: 4HB: four-helix bundle; AAV: adeno-associated virus; AD: Alzheimer disease; AIF1: allograft inflammatory factor 1; APOE: apolipoprotein E; APP: amyloid beta precursor protein; Aβ: amyloid β; BECN1: beclin 1; co-IP: co-immunoprecipitation; DEGs: differentially expressed genes; DLG4: discs large MAGUK scaffold protein 4; DUB: deubiquitinase; EBSS: Earle’s balanced salt solution; GFAP: glial fibrillary acidic protein; HRP: horseradish peroxidase; IL1B: interleukin 1 beta; IL6: interleukin 6; IPed: immunoprecipitated; KEGG: Kyoto Encyclopedia of Genes and Genomes; KO: knockout; MAP1LC3/LC3: microtubule associated protein 1 light chain 3; MLKL: mixed lineage kinase domain like pseudokinase; NSA: necrosulfonamide; OPCs: oligodendrocyte precursor cells; PFA: paraformaldehyde; PsKD: pseudo-kinase domain; SYP: synaptophysin; UB: ubiquitin; UBA52: ubiquitin A-52 residue ribosomal protein fusion product 1; UCHL3: ubiquitin C-terminal hydrolase L3; ULK1: unc-51 like autophagy activating kinase 1; UMAP: uniform manifold approximation and projection; UPS: ubiquitin-proteasome system; USP7: ubiquitin specific peptidase 7; USP9X: ubiquitin specific peptidase 9 X-linked.
研究领域:
神经科学
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分子生物学
·
细胞生物学
·
遗传学
✓ 已验证
DOI
高影响因子
MOLECULAR NEUROBIOLOGY
·
2026
·Vol. 63
·期 1
·371
·
IF 4.3
Ma Shuainan,Liu Qi,Han Wei,Liu Zhiyi,Jin Sinan,Wu He,Hua Wei
Intracerebral hemorrhage (ICH) incidence increases with age, and neuronal mitochondrial dysfunction and apoptosis post-ICH contribute to severe secondary brain injury. It is of paramount importance to explore molecular targets for protecting against brain injury after ICH. UBA52, a ubiquitin precursor protein, was found to be upregulated in brain tissues of ICH mice. Intracerebral injection of adeno-associated virus type 9 overexpressing UBA52 (AAV9-UBA52) alleviated neurological deficits and brain edema in ICH mice. In vitro and in vivo experiments demonstrated that UBA52 overexpression reduced hemin or ICH-induced apoptosis, reflected in decreased TUNEL-positive cells and reduced caspase-3 and caspase-9 levels. The augmentation of fluorescence intensity in Mitotracker labeling and the reduction of fluorescence intensity in JC-1 staining suggested that UBA52 overexpression mitigated hemin-induced mitochondrial damage. This was further evidenced by increased cellular ATP content and elevated cytochrome c levels located in mitochondria. In vivo findings showed that UBA52 overexpression reduced the quantity of degenerative neurons. UBA52 and NeuN co-localization verified its direct protective effect on neurons. IP-LC/MS and Co-IP assays identified Daxx as a UBA52-interacting protein, with UBA52 promoting Daxx ubiquitination and degradation. Rescue experiments showed Daxx overexpression abolished the protective effect of UBA52 against hemin-induced apoptosis and mitochondrial dysfunction. Collectively, this study demonstrated that UBA52 ameliorates ICH-induced secondary brain injury by promoting Daxx ubiquitination/degradation to inhibit neuronal apoptosis and mitochondrial damage, suggesting UBA52 as a potential protective target for ICH therapy.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
BIOLOGICAL TRACE ELEMENT RESEARCH
·
2023
·
IF 3.9
Peng Huixin,Huang Yanxin,Wei Guangji,Pang Yanfang,Yuan Huixiong,Zou Xiong,Xie Yu’an,Chen Wencheng
Aluminum contamination is a growing environmental and public health concern, and aluminum testicular toxicity has been reported in male rats; however, the underlying mechanisms of this toxicity are unclear. The objective of this study was to investigate the effects of exposure to aluminum chloride (AlCl 3 ) on alterations in the levels of sex hormones (testosterone [T], luteinizing hormone [LH], and follicle-stimulating hormone [FSH]) and testicular damage. Additionally, the mechanisms of toxicity in the testes of AlCl 3 -exposed rats were analyzed by proteomics. Three different concentrations of AlCl 3 were administered to rats. The results demonstrated a decrease in T, LH, and FSH levels with increasing concentrations of AlCl 3 exposure. HE staining results revealed that the spermatogenic cells in the AlCl 3 -exposed rats were widened, disorganized, or absent, with increased severe tissue destruction at higher concentrations of AlCl 3 exposure. Kyoto Encyclopedia of Genes and Genomes (KEGG) and Gene Ontology (GO) enrichment analyses revealed that differentially expressed proteins (DEPs) after AlCl 3 exposure were primarily associated with various metabolic processes, sperm fibrous sheath, calcium-dependent protein binding, oxidative phosphorylation, and ribosomes. Subsequently, DEPs from each group were subjected to protein-protein interaction (PPI) analysis followed by the screening of interactional key DEPs. Western blot experiments validated the proteomics data, revealing the downregulation of sperm-related DEPs (AKAP4, ODF1, and OAZ3) and upregulation of regulatory ribosome-associated protein (UBA52) and mitochondrial ribosomal protein (MRPL32). These findings provide a basis for studying the mechanism of testicular toxicity due to AlCl 3 exposure.
研究领域:
毒理学
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环境健康
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生殖生物学
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蛋白质组学
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分子生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）