The pathogenesis of Parkinson's disease is closely related to genetic factors. This article has systematically reviewed the research progress of molecular genetic mechanism on Parkinson's disease by focusing on the role of six high-penetrance pathogenic genes (SNCA, LRRK2, PRKN, PINK1, PARK7, and VPS35) and some risk genes (such as GBA1). These genetic variants eventually converge in three core pathogenic biological pathways, including lysosomal-autophagy pathway disorder, mitochondrial quality control disorder and α-synuclein metabolic abnormality. In-depth understanding of these molecular mechanisms is of great significance for the development of targeted therapy and realization of precision medicine for this disease.
Humans ; Parkinson Disease/metabolism* ; alpha-Synuclein/genetics* ; Leucine-Rich Repeat Serine-Threonine Protein Kinase-2/genetics* ; Genetic Predisposition to Disease ; Protein Kinases/genetics* ; Animals ; Glucosylceramidase/genetics* ; Ubiquitin-Protein Ligases/genetics*

Objective To investigate whether miR-15b-5p can alleviate airway inflammation in asthma by negatively regulating ubiquitin specific peptidase 9X (USP9X) to down-regulate the expression of phosphatidylinositol 4, 5-diphosphate 3-kinase catalytic subunit α/AKT serine/threonine kinase 1 (PIK3CA/AKT1) pathway. Methods USP9X was predicted to be a direct target of miR-15b-5p by using an online database (miRWalk), and the luciferase reporter gene assay was performed to verify it. Co-immunoprecipitation (CO-IP) was used to verify the direct binding between USP9X and PIK3CA and the role of USP9X and its small molecule inhibitor WP1130 in the deubiquitination of PIK3CA. C57 mice were randomly divided into Control group, OVA group, OVA combined with NC group and miR-15b-5p agomir group, with 10 mice in each group. BEAS-2B cells were induced with interleukin 13 (IL-13) and treated with miR-15b-5p mimic. HE, Masson, PAS, immunohistochemistry, immunofluorescence staining, flow cytometry, Western blot and quantitative real-time PCR(qRT-PCR) were performed. Results It was found that the administration of miR-15b-5p agomir and mimic could reduce peribronchial inflammatory cells and improve airway inflammation, and miR-15b-5p could target negative regulation of USP9X. USP9X could directly bind to PIK3CA and regulate PIK3CA level in a proteasome-dependent manner, and USP9X could deubiquitinate K29-linked PIK3CA protein. Down-regulation of USP9X could increase PIK3CA ubiquitination level. WP1130, a small molecule inhibitor of USP9X, has the same effect as knockdown of USP9X, both of which could increase the ubiquitination level of PIK3CA and reduce the protein level of PIK3CA. Conclusion The miR-15b-5p/USP9X/PIK3CA/AKT1 signaling pathway may provide potential therapeutic targets for asthma.
Animals ; MicroRNAs/metabolism* ; Asthma/pathology* ; Class I Phosphatidylinositol 3-Kinases/genetics* ; Ubiquitin Thiolesterase/metabolism* ; Proto-Oncogene Proteins c-akt/genetics* ; Mice ; Signal Transduction ; Mice, Inbred C57BL ; Humans ; Inflammation/genetics* ; Cell Line ; Female ; Male

Objective To explore the mechanism of ubiquitin specific peptidase 21 (USP21) increasing the stability of forkhead box protein M1 (FOXM1) and promoting M2 polarization of macrophages in endometriosis (EM). Methods Eutopic endometrial stromal cells (EESC) collected from patients and normal endometrial stromal cells (NESC) from routine health examiners were cultured in vitro, and the expression levels of USP21 and FOXM1 were detected using RT-qPCR and Western blot. EESCs were co-cultured with macrophages. M1 polarization markers of interleukin 6 (IL-6) and CXC chemokine ligand 10 (CXCL10) and M2 polarization markers of CD206 and fibronectin 1 (FN1) were tested using RT-qPCR. M2 marker CD206 was further detected by flow cytometry. IL-6, tumor necrosis factor-alpha (TNF-α), IL-10, and transforming growth factor-beta (TGF-β) levels in cell supernatant were detected by ELISA. Co-immunoprecipitation was used to assess the interaction between USP21 and FOXM1, and the ubiquitination level of FOXM1. FOXM1 protein stability was detected through cycloheximide (CHX) assay. Results USP21 and FOXM1 expression levels in the EESC group were significantly increased compared with those in the NESC group; compared with the NESC + M0 group, the EESC + M0 group showed no significant difference in the expression of M1 polarization markers (IL-6 and CXCL10), but increased expression of M2 polarization markers (CD206 and FN1), along with notably increased number of M2 macrophages; there was no significant difference in IL-6 and TNF-α levels, but increased levels of IL-10 and TGF-β in the cell supernatant. The above findings indicated that the deubiquitinase USP21 was highly expressed in EM, promoting M2 polarization of macrophages. Knocking down USP21 or FOXM1 can inhibit M2 polarization of EM macrophages. USP21 interacted with FOXM1 in EESC, leading to a decrease in FOXM1 ubiquitination level and an increase in FOXM1 protein stability. Overexpression of FOXM1 reversed the inhibitory effect of knocking down USP21 on M2 polarization of EM macrophages. Conclusion The deubiquitinase USP21 interacts with FOXM1 to increase the stability of FOXM1 and promote M2 polarization of EM macrophages.
Humans ; Forkhead Box Protein M1/genetics* ; Female ; Macrophages/cytology* ; Endometriosis/genetics* ; Ubiquitin Thiolesterase/genetics* ; Cells, Cultured ; Endometrium/metabolism* ; Ubiquitination ; Adult ; Interleukin-10/metabolism* ; Interleukin-6/metabolism* ; Protein Stability ; Stromal Cells/metabolism*

Ischemic stroke (IS) is a prevalent neurological disorder often resulting in significant disability or mortality. Resveratrol, extracted from Polygonum cuspidatum Sieb. et Zucc. (commonly known as Japanese knotweed), has been recognized for its potent neuroprotective properties. However, the neuroprotective efficacy of its derivative, (E)-4-(3,5-dimethoxystyryl) quinoline (RV02), against ischemic stroke remains inadequately explored. This study aimed to evaluate the protective effects of RV02 on neuronal ischemia-reperfusion injury both in vitro and in vivo. The research utilized an animal model of middle cerebral artery occlusion/reperfusion and SH-SY5Y cells subjected to oxygen-glucose deprivation and reperfusion to simulate ischemic conditions. The findings demonstrate that RV02 attenuates neuronal mitochondrial damage and scavenges reactive oxygen species (ROS) through mitophagy activation. Furthermore, Parkin knockdown was found to abolish RV02's ability to activate mitophagy and neuroprotection in vitro. These results suggest that RV02 shows promise as a neuroprotective agent, with the activation of Parkin-mediated mitophagy potentially serving as the primary mechanism underlying its neuroprotective effects.
Animals ; Ubiquitin-Protein Ligases/genetics* ; Mitophagy/drug effects* ; Resveratrol/analogs & derivatives* ; Neuroprotective Agents/pharmacology* ; Humans ; Neurons/metabolism* ; Reactive Oxygen Species/metabolism* ; Ischemic Stroke/genetics* ; Male ; Quinolines/pharmacology* ; Mice ; Fallopia japonica/chemistry* ; Mitochondria/metabolism* ; Reperfusion Injury/metabolism* ; Rats ; Mice, Inbred C57BL ; Disease Models, Animal

Geminiviruses cause substantial crop yield losses worldwide. The replication initiator protein (Rep) encoded by geminiviruses is indispensable for geminiviral replication. The Rep protein encoded by beet severe curly top virus (BSCTV, genus Curtovirus, family Geminiviridae) induces VARIANT IN METHYLATION 5 (VIM5) expression in Arabidopsis leaves upon BSCTV infection. VIM5 functions as a ubiquitination-related E3 ligase to promote the proteasomal degradation of methyltransferases, resulting in reduction of methylation levels in the BSCTV C2-3 promoter. However, the specific domains of Rep responsible for VIM5 induction remain poorly characterized. Although Rep proteins from several geminiviruses act as viral suppressors of RNA silencing (VSRs), whether BSCTV Rep also possesses VSR activity remains to be illustrated. In this study, we employed a transient expression system in the 16c-GFP transgenic and the wild-type Nicotiana benthamiana plants to analyze the VSR and the VIM5-inducing activities of different truncated Rep proteins haboring distinct domains. We found that the N-terminal domain (amino acids 1-180) of Rep suppressed GFP silencing in 16c-GFP transgenic N. benthamiana leaves. The minimal N-terminal fragment (amino acids 1-104) induced VIM5 expression upon co-infiltration, while C-terminal truncations lacked VIM5-inducing activity. Our results indicate that the N-terminal domain of Rep encoded by BSCTV mediates the suppression of RNA silencing and induces VIM5 expression. Thus, our findings contribute to a better understanding of interactions between geminiviral Rep and plant hosts.
Geminiviridae/genetics* ; Nicotiana/metabolism* ; Arabidopsis/metabolism* ; RNA Interference ; Viral Proteins/metabolism* ; Arabidopsis Proteins/metabolism* ; Plants, Genetically Modified/metabolism* ; Protein Domains ; Plant Diseases/virology* ; Methyltransferases/metabolism* ; Ubiquitin-Protein Ligases/metabolism* ; DNA Helicases/genetics*

OBJECTIVE: To explore the genotype-phenotype relationship in a child with Opitz G/BBB syndrome (OS) with mild clinical phenotype. METHODS: A child with motor developmental delay as the initial symptom admitted to Xi'an Children's Hospital on June 10, 2021 was selected for this study. Clinical data were collected, and peripheral blood samples were obtained from the child and his mother. Whole exome sequencing (WES) was performed to identify genetic variant in the child. Candidate variant were verified by Sanger sequencing to assess inheritance patterns and pathogenicity. Real-time fluorescence quantitative PCR (RT-qPCR) and Western blot (WB) analyses were conducted to evaluate the effects of the variant on mRNA and protein expression, respectively, using recombinant expression plasmids generated in vitro. This study was approved by the Medical Ethics Committee of Xi'an Children's Hospital (Ethics No. 20240045). RESULTS: The child, a 9-month-and-7-day-old boy, presented with a low nasal bridge, hypertelorism, and difficulty sitting independently. Echocardiography revealed an atrial septal defect. WES identified a homozygous variant in the MIDI gene, c.1483C>T (p.R495X), which was confirmed by Sanger sequencing and found to be inherited from the mother.Recombinant expression plasmids were successfully constructed. RT-qPCR analysis showed that the variant significantly reduced MIDI gene mRNA expression, while WB results indicated that the variant led to the production of a truncated protein. CONCLUSION The mild clinical phenotype of OS in this child may be attributed to the mRNA degradation escape mechanism induced by the nonsense variant c.1483C>T (p.R495X) in the MIDI gene. These findings provide valuable diagnostic insights for this pedigree and contribute to the understanding of the genotype-phenotype correlation in OS.
Humans ; Male ; Infant ; Transcription Factors/metabolism* ; Microtubule Proteins/genetics* ; Craniosynostoses/genetics* ; Hypospadias/genetics* ; Codon, Nonsense/genetics* ; RNA, Messenger/metabolism* ; Female ; RNA Stability/genetics* ; Phenotype ; Nuclear Proteins/genetics* ; Ubiquitin-Protein Ligases ; Esophagus/abnormalities* ; Hypertelorism

OBJECTIVES: To investigate the role of nucleolar pre-rRNA processing protein NIP7 (NIP7) in maintaining the malignant phenotype of anaplastic thyroid cancer (ATC) and its molecular mechanisms. METHODS: NIP7 expression in ATC tissues and its gene knock-out effects in ATC cells were analyzed using gene expression microarray (GSE33630), proteome database (IPX0008941000) and the Dependency Map database, respectively. Expression and localization of NIP7 in normal thyroid cells, papillary thyroid cancer cells, and ATC cells were detected by Western blotting. Small interfering RNA (siRNA) was transfected into ATC cells, and the knockdown efficiency of NIP7 was detected by quantitative reverse transcription polymerase chain reaction (qRT-PCR) and Western blotting. Cell proliferation was assessed by CCK-8 assay, colony formation was evaluated by colony formation assay, and tumor growth was assessed by xenograft tumor model in nude mice. SUnSET (surface sensing of translation) assay combined with co-immunoprecipitation were employed to evaluate the effect of NIP7 silencing on ubiquitin-conjugating enzyme E2 C (UBE2C) translation. Finally, gene set enrichment analysis was used to identify shared pathways of NIP7 and UBE2C, which were validated by qRT-PCR. RESULTS: Compared with normal tissues and papillary thyroid cancer, NIP7 was significantly upregulated in ATC tissues, and had a gene knock-out fitness effect on different ATC cell lines. The relative protein levels of NIP7 in ATC cells were significantly higher than those in normal thyroid follicular cells, and the protein was mainly expressed in the nucleus. NIP7 silencing significantly inhibited cell proliferation and reduced colony formation. Xenograft tumor model showed that NIP7 knockdown significantly slowed down the growth of ATC xenograft, and the tumor volume and weight were significantly lower than those in the control group (all P<0.05). NIP7 silencing downregulated the protein level of UBE2C, but did not affect the expression of UBE2C mRNA. Compared to the control group, UBE2C silencing significantly inhibited ATC cells proliferation (P<0.01) and colony formation (P<0.05). UBE2C overexpression reversed the proliferation-inhibitory effect induced by NIP7 silencing (P<0.01). Gene set enrichment analysis indicated that NIP7 and UBE2C were both involved in DNA replication. NIP7 or UBE2C silencing could significantly downregulate the expression levels of DNA polymerase epsilon, catalytic subunit 2 and replication factor C4 in DNA replication pathway. CONCLUSIONS NIP7 promotes ATC tumor growth by upregulating UBE2C to mediate DNA replication.
Humans ; Ubiquitin-Conjugating Enzymes/genetics* ; Thyroid Neoplasms/genetics* ; Thyroid Carcinoma, Anaplastic/genetics* ; Animals ; Mice, Nude ; Mice ; Cell Line, Tumor ; Cell Proliferation ; Up-Regulation ; RNA, Small Interfering/genetics* ; Nuclear Proteins/metabolism* ; Gene Expression Regulation, Neoplastic

E3 ubiquitin ligase is a key enzyme that determines substrate specificity during ubiquitination and plays an important role in regulating the degradation of tumor suppressor or oncogenic proteins. E3 ubiquitin ligase is involved in regulating leukemia cell differentiation, cell cycle and immune response, and it is closely related to the occurrence and development of acute myeloid leukemia (AML). Targeting highly specific E3 ubiquitin ligase can be used as an effective treatment for AML. This article reviewed the latest progress of E3 ubiquitin ligase in the diagnosis and treatment of AML, aiming to provide insights for the precise targeted therapy of this disease.
Humans ; Ubiquitin-Protein Ligases/metabolism* ; Leukemia, Myeloid, Acute/therapy*

OBJECTIVE: To elucidate the role and underlying mechanism of ubiquitin-specific protease 35 (USP35) in ferroptosis of rheumatoid arthritis-fibroblast like synoviocytes (RA-FLS), thereby enhancing our comprehension of the pathogenesis of RA and identifying potential therapeutic targets for its treatment. METHODS: (1) RA-FLS were cultured in vitro and transduced with lentiviral vectors to establish stable cell lines: A USP35-knockdown line (short hairpin ribonucleic acid of USP35, shUSP35) and its control (negtive control of short hairpin ribonucleic acid, shNC), as well as a overexpression of USP35 line (USP35 OE) and its control (Vector). To investigate the role of USP35 in ferroptosis regulation, a ferroptosis model was induced in RA-FLS by treatment with 1 μmol/L Erastin. The cells were divided into six groups: shNC, shNC + Erastin, shUSP35 + Erastin, Vector, Vector + Erastin, and USP35 OE + Erastin. (2) Cell viability was detected using the cell counting kit-8 (CCK-8). (3) Reactive oxygen species (ROS), malondialdehyde (MDA), glutathione/glutathione disulfide (GSH/GSSG) ratios, and Ferrous ion (Fe²⁺) levels were measured using specific assay kits to evaluate oxidative stress, lipid peroxidation, and glutathione redox status in the cells. (4) Protein expression levels of solute carrier family 7 member 11 (SLC7A11) and glutathione peroxidase 4 (GPX4) were detected using Western blotting to investigate their potential involvement in USP35-mediated ferroptosis regulation. RESULTS: (1) Compared with the shNC +Erastin group, the cell viability of the shUSP35+Erastin group was significantly decreased (P < 0.001), while it was notably increased in the USP35 OE+Erastin group compared with the Vector+Erastin group (P < 0.001). These findings indicated that USP35 could alleviate the inhibitory effect of Erastin on RA-FLS cell viability. (2) In comparison to the shNC+Erastin group, the levels of ROS (P < 0.001), MDA (P < 0.05), and Fe²⁺ (P < 0.001) were significantly elevated, and the GSH/GSSG ratio was increased (P < 0.05) in the shUSP35+Erastin group. Conversely, the levels of ROS (P < 0.001), MDA (P < 0.05), and Fe²⁺ (P < 0.05) were significantly decreased, and the GSH/GSSG ratio was decreased (P < 0.05) in the USP35 OE+Erastin group compared with the Vector+Erastin group. These results suggested that USP35 could inhibit Erastin-induced oxidative stress and lipid peroxidation in RA-FLS. (3) In Erastin-induced RA-FLS, the expression of USP35 was positively correlated with the protein levels of SLC7A11 and GPX4, indicating a potential mechanism by which USP35 regulated ferroptosis in these cells. CONCLUSION USP35 inhibits ferroptosis in RA-FLS, potentially through the increased expression of SLC7A11 and GPX4.
Ferroptosis ; Humans ; Arthritis, Rheumatoid/metabolism* ; Synoviocytes/pathology* ; Reactive Oxygen Species/metabolism* ; Ubiquitin-Specific Proteases/metabolism* ; Fibroblasts/pathology* ; Cell Survival ; Piperazines/pharmacology* ; Endopeptidases/metabolism* ; Cells, Cultured ; Cell Line ; Amino Acid Transport System y+

OBJECTIVE: To investigate the effects of Bushen Huoxue Granule on the ubiquitin-proteasome system (UPS) in an in vitro model of Parkinson's disease. METHODS: After treated with 1-methyl-4-phenylpyridinium (MPP⁺, 1 mmol/L) for 24 h, the cells were incubated with drug-free serum, Madopar-containing serum or Bushen Huoxue Granule-containing serum (BCS, 5%, 10%, and 20%) for another 24 h. The levels of α-synuclein (α-syn), tyrosine hydroxylase (TH) and UPS-related proteins were detected by Western blot. The expression levels of α-syn in PC12 cells were also analyzed by Western blot after treated with proteasome inhibitor MG132 and WT-α-syn plasmid transfection, respectively, as well as the alterations induced by subsequent BCS intervention. Immunocytochemistry was performed to determine the changes in α-syn phosphorylation at serine 129 (pSer129-α-syn) expression. The 20S proteasome levels were measured by enzyme-linked immunosorbnent assay. RESULTS: BCS (volume fraction ⩽20%) intervention could alleviate the MMP⁺-induced cell viability decrease (P<0.05). In the MPP⁺ treated cells, α-syn was up-regulated, while TH and proteins of UPS such as ubiquitin (Ub), Ub binding with Ub-activating enzyme (UBE1), Parkin and Ub C-terminal hydrolase-1 (UCHL-1) were down-regulated (P<0.05). BCS intervention could attenuate the above changes (P<0.05). The activity of BCS on blocking α-syn accumulation was weakened by MG132 (P<0.05). While α-syn level was significantly increased in cells transfected with plasmid, and reduced by BCS intervention (P<0.05). pSer129-α-syn was increased in MPP⁺-induced PC12 cells, whereas decreased by later BCS intervention (P<0.05). The 20S proteasome activity of MPP⁺-induced PC12 cells was decreased, but increased after BCS intervention (P<0.05). CONCLUSION BCS intervention protected UPS function, increased 20S proteasome activity, promoted pathological α-syn clearance, restored cell viability, and reversed the damage caused by MPP⁺ in the in vitro model of Parkinson's disease.
PC12 Cells ; alpha-Synuclein/metabolism* ; Rats ; Animals ; 1-Methyl-4-phenylpyridinium/toxicity* ; Proteasome Endopeptidase Complex/metabolism* ; Drugs, Chinese Herbal/pharmacology* ; Ubiquitin/metabolism* ; Cell Survival/drug effects* ; Phosphorylation/drug effects* ; Tyrosine 3-Monooxygenase/metabolism*