GEN POMP: acerca de su participación en los mecanismos de autoinmunidad e inflamación

En esta revisión abordamos la autoinmunidad, destacando los mecanismos defectuosos en la tolerancia inmunológica y su relación con enfermedades autoinmunes. Nos centramos en la proteína POMP y el sistema ubiquitina-proteosoma, explicando su función en la degradación proteínica y su papel en la formación del inmunoproteosoma. Se detalla la estructura del proteosoma, la ubiquitinización, y se destaca la influencia de POMP en la respuesta inflamatoria, especialmente en la formación del inmunoproteosoma bajo la estimulación del interferón. Además, se explora la implicación de POMP en procesos autoinflamatorios, como los síndromes asociados al proteosoma, y se menciona su relación con enfermedades autoinmunes, incluyendo el lupus eritematoso sistémico. Se describen casos clínicos que resaltan la importancia de POMP en la autoinmunidad.

This publication addresses autoimmunity, and defective mechanisms in immunological tolerance as well as their connection to autoimmune diseases. It focuses on the POMP protein and the ubiquitin-proteasome system, explaining its role in protein degradation and its involvement in the formation of the immunoproteasome. The structure of the proteasome, ubiquitination, and the influence of POMP on the inflammatory response are detailed, highlighting the formation of the immunoproteasome under interferon stimulation. Additionally, the text explores the implication of POMP in autoinflammatory processes, such as proteasome-associated syndromes, and mentions its association with autoimmune diseases, including systemic lupus erythematosus. Clinical cases are described to underscore the significance of POMP in autoimmunity.

Ubiquitin-specific protease 42 regulates osteogenic differentiation of human adipose-derived stem cells / 北京大学学报(医学版)

Objective:To explore the effect of ubiquitin-specific protease 42(USP42)on osteogenic differentiation of human adipose-derived stem cells(hASCs)in vivo and in vitro.Methods:A combina-tion of experiments was carried out with genetic depletion of USP42 using a lentiviral strategy.Alkaline phosphatase(ALP)staining and quantification,alizarin red S(ARS)staining and quantification were used to determine the osteogenic differentiation ability of hASCs under osteogenic induction between the experimental group(knockdown group and overexpression group)and the control group.Quantitative re-verse transcription PCR(qRT-PCR)was used to detect the expression levels of osteogenesis related genes in the experimental group and control group,and Western blotting was used to detect the expression levels of osteogenesis related proteins in the experimental group and control group.Nude mice ectopic im-plantation experiment was used to evaluate the effect of USP42 on the osteogenic differentiation of hASCs in vivo.Results:The mRNA and protein expressions of USP42 in knockdown group were significantly lower than those in control group,and those in overexpression group were significantly higher than those in control group.After 7 days of osteogenic induction,the ALP activity in the knockdown group was sig-nificantly higher than that in the control group,and ALP activity in overexpression group was significantly lower than that in control group.After 14 days of osteogenic induction,ARS staining was significantly deeper in the knockdown group than in the control group,and significantly lighter in overexpression group than in the control group.The results of qRT-PCR showed that the mRNA expression levels of ALP,os-terix(OSX)and collagen type Ⅰ(COL Ⅰ)in the knockdown group were significantly higher than those in the control group after 14 days of osteogenic induction,and those in overexpression group were signifi-cantly lower than those in control group.The results of Western blotting showed that the expression levels of runt-related transcription factor 2(RUNX2),OSX and COL Ⅰ in the knockout group were significant-ly higher than those in the control group at 14 days after osteogenic induction,while the expression levels of RUNX2,OSX and COL Ⅰ in the overexpression group were significantly lower than those in the control group.Hematoxylin-eosin staining of subcutaneous grafts in nude mice showed that the percentage of osteoid area in the knockdown group was significantly higher than that in the control group.Conclusion:Knockdown of USP42 can significantly promote the osteogenic differentiation of hASCs in vitro and in vi-vo,and overexpression of USP42 significantly inhibits in vivo osteogenic differentiation of hASCs,and USP42 can provide a potential therapeutic target for bone tissue engineering.

Screening of UBE2S interacting protein and construction of prognostic model in hepatocellular carcinoma / 吉林大学学报(医学版)

Objective:To screen the interacting protein of ubiquitin-conjugating enzyme E2S(UBE2S)and construct the hepatocellular carcinoma(HCC)based on UBE2S interacting protein prognosis model(UIPM),and to discuss the value of UIPM in assessing the prognosis of the HCC patients.Methods:Co-immunoprecipitation(Co-IP)was used to screen the protein complexes binding to Flag-UBE2S.After validation by sodium dodecyl sulphate-polyacrylamide gel electrophoresis(SDS-PAGE)and Western blotting methods;liquid chromatography-mass spectrometer(LC-MS)was used to identify the UBE2S interacting proteins;Gene Ontology(GO)functional enrichment analysis and Kyoto Encyclopedia of Genes and Genomes(KEGG)signaling pathway enrichment analysis were conducted on these proteins;the prognosis-related proteins from The Cancer Genome Atlas(TCGA)were cross-referenced with UBE2S interacting proteins by survival package of R software;the key proteins were extracted through LASSO regression analysis to build the UIPM;the prognostic model risk scoring formula was established.The HCC patients in TCGA were divided into high risk group and low risk group based on median value of the risk scores.The predictive accuracy of UIPM was evaluated by receiver operating characteristic curve(ROC),and the predictive accuracy was further validated by International Cancer Genome Consortium(ICGC)Database;univariate regression analysis and multivariate Cox regression analysis were used to detect whether the UIPM risk score was an independent prognostic factor for HCC.Furthermore,the nomogram model was built.Results:A total of 97 UBE2S interacting proteins were identified through Co-IP combined with LC-MS analysis.The GO functional enrichment analysis and KEGG signaling pathway enrichment analysis results showed that the interacting proteins were closely associated with cysteine-type endopeptidase activity,oxidative stress,and cell death.The TCGA revealed 5 163 HCC prognosis-related proteins;after intersecting with UBE2S interacting proteins,40 prognosis-related interacting proteins were found.Seven key proteins were determined through LASSO regression analysis,including UBE2S,heat shock protein family A member 8(HSPA8),heterogeneous nuclear ribonucleoprotein H1(HNRNPH1),chaperonin containing TCP1 subunit 3(CCT3),eukaryotic translation initiation factor 2 subunit 1(EIF2S1),receptor for activated C kinase 1(RACK1),and actin related protein 2/3 complex subunit 4(ARPC4),and the UIPM was constructed.There was significant difference in survival rate of the patients between high risk group and low risk group(P<0.05).The ROC curve analysis results showed the area under ROC curve(AUC)values of UIPM for predicting 1-year,2-year,and 3-year survival risk scores of the HCC patients were all greater than 0.7,indicating the model had high predictive accuracy.This was also confirmed by ICGC Database data.The univariate and multivariate Cox regression analysis results showed that the UIPM risk score was an independent prognostic risk factor for the HCC patients(P<0.05).The nomogram results showed good consistency between predicted survival rate and actual survival rate of the patient.Conclusion:A total of 97 interacting proteins that interact with UBE2S may promote the occurence and devolopment of HCC through oxidative stress and dysregulation of ferroptosis pathways.The UIPM risk score is an independent risk factor for the prognosis of HCC and can be used to predict the outcomes of the patients.UBE2S,HSPA8,HNRNPH1,CCT3,EIF2S1,RACK1,and ARPC4 could be regarded as the new biomarkers and therapeutic targets for HCC.

Mechanisms for phase separation between TDP-43 and ubiquitin in vitro / 军事医学

Objective To explore the characteristics and mechanism of phase separation between TAR DNA binding protein-43(TDP-43)and ubiquitin.Methods The TARDBP gene and its truncated genes were inserted into vectors to construct recombinant plasmids for expression and protein purification.The phase separation system of ubiquitin and TDP-43 was constructed in vitro.The characteristics of the droplets formed via liquid-liquid phase separation were observed by fluorescence microscopy.The plasmids of ubiquitin and TDP-43 were co-transfected into HEK293T cells to observe aggregates containing TDP-43 and ubiquitin and find out whether TDP-43 could be ubiquitinated.Results The GFP-8Ub,TDP-43 full-length(FL)and truncated proteins were purified.TDP-43 FL and C-terminal domain(CTD)proteins were able to form droplets via phase separation with ubiquitin.The droplets changed into solid-like aggregates after prolonged incubation.Insolvable aggregates containing TDP-43 and ubiquitin were formed.TDP-43 was ubiquitinated under stress conditions in HEK293T cells after being co-transfected with ubiquitin and TDP-43 recombinant plasmids.Conclusion TDP-43 undergoes co-phase separation with ubiquitin,mainly driven by the multivalent interaction between TDP-43′s CTD structural domain and ubiquitin.The droplets finally form aggregates with solid-like properties.Under stress conditions,especially when the protein homeostasis is disrupted,TDP-43 and ubiquitin form aggregates while TDP-43 is ubiquitinated.This study reveals the basic mechanism of TDP-43 co-phase separation with ubiquitin and liquid-solid transformation.

Function and research progress of ubiquitin-specific protease 7 in colorectal cancer / 临床外科杂志

Ubiquitin-specific protease 7(USP7)is a deubiquitinating enzyme involved in a wide range of cellular processes,playing a key role in the regulation of cell proliferation and apoptosis,cell division,differentiation,DNA damage repair,epigenetic regulation and other biological processes.This article briefly summarizes the structure and extensive biological functions of USP7,and also describes the research progress of USP7 in colorectal cancer in recent years and potential directions for future research.

Study on Serum WWP1 and NLRP3 Expression Levels and Their Clinical Value in Patients with Heart Failure with Preserved Ejection Fraction / 现代检验医学杂志

Objective To investigate the expression level and clinical significance of WW domain-containing E3 ubiquitin protein ligase 1(WWP1)and nucleotide-binding oligomerization domain-like receptor protein 3(NLRP3)in patients with heart failure with preserved ejection fraction(HFpEF).Methods A total of 153 patients with HFpEF admitted to Fengfeng General Hospital of North China Medical and Health Group from January 2021 to September 2022 were collected as the observation group.According to the New York Heart Association(NYHA)cardiac function grading of patients,they were grouped into cardiac function grading Ⅰ～Ⅱ group(n=64)and cardiac function grading Ⅲ～Ⅳ group(n=89),while 148 healthy volunteers were collected as the control group.The correlation between serum WWP1 and NLRP3 levels and cardiac function indexes of patients was explored by Pearson analysis.The diagnostic value of serum WWP1 and NLRP3 levels on the severity of heart failure in HFpEF patients was analyzed by the receiver operating characteristic(ROC)curve.Results Compared with the control group,the expression levels of WWP1(1.68±0.35 vs 1.04±0.19)and NLRP3(6.72±1.26 ng/ml vs 4.57±0.84 ng/ml)in the observation group were significantly increased,and the differences were statistically significant(t=19.623,17.359,all P<0.05).Compared with grade Ⅰ to Ⅱ groups,WWP1(1.87±0.39 vs 1.42±0.32)and NLRP3(7.53±1.40 ng/ml vs 5.59±1.18 ng/ml)expression levels in grade Ⅲ to Ⅳ groups were significantly increased and the differences were statistically significant(t=7.744,9.017,all P<0.05).The differences of heart rate,left atrial diameter(LAD),left ventricular end-diastolic diameter(LVEDD),left ventricular end-diastolic diameter(LVEDD),left atrial diameter(LAD),left ventricular end-diastolic diameter(LVEDD),left ventricular end-diastolic posterior wall thickness(LVPWT),left ventricular ejection fraction(LVPWT),left ventricular ejection fraction(LVEF),peak mitral early diastolic velocity(E)/peak late diastolic velocity(A)and the incidence of atrial fibrillation between the cardiac function grade Ⅰ to Ⅱ groups and the grade Ⅲ to Ⅳ groups were significant(t/χ2=2.757～7.069,all P<0.05).Serum WWP1 level in HFpEF patients was positively correlated with LAD,LVEDD and LVPWT(r=0.547,0.471,0.536,all P<0.05),and negatively correlated with LVEF and E/A(r=-0.485,-0.417,all P<0.05).Serum NLRP3 level was positively correlated with LAD,LVEDD and LVPWT(r=0.534,0.494,0.520,all P<0.05),and negatively correlated with LVEF and E/A(r=-0.462,-0.523,all P<0.05).ROC results showed that the area under the curve(AUC)of serum WWP1 and NLRP3 levels alone for diagnosing the severity of heart failure in HFpEF patients was 0.825 and 0.855,respectively,and the AUC(0.924)diagnosed by the combination of the two was significantly greater than that diagnosed by the serum WWP1 alone and the AUC diagnosed by the NLRP3 alone(Z=3.600,P<0.001;Z=3.053,P=0.002).Conclusion The levels of serum WWP1 and NLRP3 were increased in patients with HFpEF,which were closely related to the cardiac function of patients.Serum WWP1 and NLRP3 have certain diagnostic value for the severity of heart failure in patients with HFpEF.

Effect of ganoderma spore on mitochondrial autophagy and apoptosis in testicular tissue of diabetic rats / 中国组织工程研究

BACKGROUND:As a common complication of diabetes mellitus,male reproductive disorders have received increasing attention in recent years.Ganoderma spore have hypoglycemic,antioxidant and anti-inflammatory effects,but the regulatory mechanism for diabetic testicular tissue has not been fully elucidated. OBJECTIVE:To investigate the effect of ganoderma spore on the PTEN-induced kinase 1/E3 ubiquitin ligase pathway and cell apoptosis in testicular tissue of diabetic rats. METHODS:Forty male Sprague-Dawley rats were randomly divided into normal group,high fat and high sugar group,diabetic group and ganoderma spore group,with 10 rats in each group.The latter three groups were given high fat/high sugar diet until the end of the experiment.After 1 month of high fat/high sugar diet,the diabetic and ganoderma spore groups were given intraperitoneal injection of streptozotocin(30 mg/kg per day)to establish type 2 diabetic rat models.After successful modeling,the ganoderma spore group was intragastrically given ganoderma spore(300 mg/kg per day),and the other groups were given the same amount of normal saline for continuous 12 weeks.The sperm number and morphology were detected.The histopathological changes of the testicle were observed.Serum testosterone and oxidative stress levels in testicular tissue were measured.The levels of PTEN-induced kinase 1,E3 ubiquitin ligase,and anti-nucleoporin p62 were analyzed by immunohistochemistry and the expression of PTEN-induced kinase 1,E3 ubiquitin ligase,anti-nucleoporin p62,programmed cell death-1,microtubule-associated protein light chain 3 Ⅱ/Ⅰ,caspase 3,cleaved-caspase 3 were detected by western blot assay. RESULTS AND CONCLUSION:Compared with the normal group and the high fat and high sugar group,the diabetic group had decreased sperm number(P＜0.01),increased sperm malformation rate(P＜0.01),and decreased serum testosterone level(P＜0.01).Compared with the diabetic group,ganoderma spore intervention could increase the sperm number(P＜0.05),decrease the malformation rate(P＜0.01),and increase the serum testosterone level(P＜0.01).Compared with the normal group and the high fat and high sugar group,the malondialdehyde level in testis tissue was increased in the diabetic group(P＜0.01),while the levels of glutathione deoxidase and superoxide dismutase decreased(P＜0.01).Compared with the diabetic group,the malondialdehyde level in testis tissue was decreased in the ganoderma spore group(P＜0.01),and the levels of glutathione deoxidase and superoxide dismutase increased(P＜0.01).Immunohistochemical staining showed that compared with the normal group and the high fat and high sugar group,the positive expressions of PTEN-induced kinase 1 and E3 ubiquitin ligase in testicular tissue were decreased in the diabetic group,while the positive expressions of anti-nucleoporin p62 were increased.Compared with the diabetic group,the positive expressions of PTEN-induced kinase 1 and E3 ubiquitin ligase in testicular tissue e were increased in the ganoderma spore group,while the positive expression of anti-nucleoporin p62 was decreased.Western blot assay results indicated that compared to the normal group and the high fat and high sugar group,the expression of PTEN-induced kinase 1 and E3 ubiquitin ligase,programmed cell death-1 and the ratio of microtubule-associated protein light chain 3 Ⅱ/Ⅰ protein were decreased in the diabetic group(P＜0.05 or P＜0.01),while the expressions of anti-nucleoporin p62,caspase3 and cleaved-caspase3 were increased(P＜0.01).Compared with the diabetic group,ganoderma spore intervention could elevate the expression of PTEN-induced kinase 1 and E3 ubiquitin ligase,programmed cell death-1 and the ratio of microtubule-associated protein light chain 3 Ⅱ/Ⅰ protein(P＜0.05 or P＜0.01)as well as reduce the expressions of anti-nucleoporin p62,caspase3 and cleaved-caspase3(P＜0.05 or P＜0.01).Overall,ganoderma spores may activate the PTEN-induced kinase 1/E3 ubiquitin ligase pathway to enhance autophagy in testicular tissue and reduce apoptosis in tissue cells,so as to protect testicular tissue.

Clinical analysis of contrast-enhanced ultrasound combined with serum SMURF1 detection in the diagnosis of thyroid cancer / 局解手术学杂志

Objective To investigate the diagnostic value of contrast-enhanced ultrasound(CEUS)combined with serum Smad ubiquitin regulatory factor 1(SMURF1)detection for thyroid cancer.Methods A total of 144 suspected thyroid cancer patients admitted to Lishui branch of Zhongda Hospital Affiliated to Southeast University from February 2019 to February 2020 were selected as the study subjects.Based on the histopathological results,they were divided into the thyroid cancer group(76 cases)and the benign group(68 cases).All patients underwent contrast-enhanced ultrasound examination and serum SMURF1 level detection;the diagnostic value of contrast-enhanced ultrasound parameters,serum SMURF1 detection alone,and the combination of the two methods for thyroid cancer were analyzed.Results Contrast-enhanced ultrasound parameters peak intensity(PI),mean perfusion intensity(SImean)and maximum perfusion intensity(SImax)in the thyroid cancer group were lower than those in the benign group,and the level of SMURF1 mRNA was higher than that in the benign group(P<0.05).The sensitivity of contrast-enhanced ultrasound parameter SImax in the diagnosis of thyroid cancer was 82.89%,the specificity was 72.06%,the accuracy was 77.78%,and the Kappa value was 0.552.The sensitivity of serum SMURF1 in the diagnosis of thyroid cancer was 65.79%,the specificity was 94.12%,the accuracy was 79.17%,and the Kappa value was 0.589.The sensitivity,specificity,accuracy and Kappa value of SImax combined with serum SMURF1 in the diagnosis of thyroid cancer were 97.37%,85.29%,91.67%and 0.832,respectively,which were higher than those of SImax and SMURF1 alone(P<0.05),the AUC of the combination of the two methods was 0.927,which was significantly higher than that of the two methods alone(Zcombined vs.SImax=3.999,P<0.001;Zcombined vs.SMURF1=3.270,P=0.001).Conclusion Contrast-enhanced ultrasound combined with serum SMURF1 detection can improve the diagnostic efficiency of thyroid cancer,which may avoid the over-diagnosis on the premise of ensuring the effective diagnosis of thyroid cancer patients.

Research progress on SENP1/HIF-1α regulation of vascular differentiation of dental pulp stem cells / 中国医师杂志

Dental pulp stem cells (DPSC) are pluripotent stem cells with high differentiation potential isolated from dental pulp. Using DPSC for vascular regeneration may be a good option. Hypoxia inducible factor-1α (HIF-1α) is an upstream gene of vascular endothelial growth factor (VEGF), and the small ubiquitin like protease 1 (SENP1) can reverse the small ubiquitin like (SUMO) modification of HIF-1α. Through the regulation of SENP1/HIF-1α, good vascular regeneration characteristics have been demonstrated in many in vitro and in vivo experiments. The SENP1/HIF-1α signaling axis has varying degrees of promoting and inhibiting effects on many solid tumors. Although there is relatively little literature on the role of the SENP1/HIF-1α signaling axis in dental pulp stem cells, it can be determined that SENP1/HIF-1α plays an important role in the angiogenesis of dental pulp stem cells. This article will elucidate the SENP1/HIF-1α signaling pathway and its mechanism of promoting vascular differentiation of DPSC.

Effects of targeted inhibition of deubiquitinase USP7/USP47 on proliferation and apoptosis of acute myeloid leukemia cells with or without Flt3-ITD mutation / 中华微生物学和免疫学杂志

Objective:To investigate the effects of ubiquitin-specific protease (USP) 7/47 inhibitor (Cat. No. 1247825-37-1) on the proliferation and apoptosis of acute myeloid leukemia (AML) cells with or without internal tandem duplications of the Flt3 gene (Flt3-ITD). Methods:ATP assay was used to detect the effects of 1247825-37-1 on the cell viability of two AML cell lines (MOLM13 and MV4-11) harboring Flt3-ITD mutation and one AML cell line (THP-1) without Flt3-ITD mutation as well as the primary Flt3-ITD-mutant and non-mutant AML cells from patient samples. Flow cytometry was used to detect the apoptosis of AML cell lines treated by different concentrations of 1247825-37-1.Results:Compared with the control group, 1247825-37-1 was able to significantly inhibit the proliferation of MOLM13, MV4-11 and THP-1 cells ( P<0.000 1). Besides, the cell viability of primary AML cells was also inhibited by 1247825-37-1, and a stronger inhibitory effect on non-mutant AML cells was observed. The USP7/USP47 inhibitor 1247825-37-1 could inhibit the proliferation of AML cells in a dose-dependent manner and a low dose (2 or 4 μmol/L) of 1247825-37-1 would be effective. Moreover, 1247825-37-1 was also able to efficiently induce the apoptosis of above AML cell lines in a dose-dependent manner. Conclusions:The USP7/USP47 inhibitor 1247825-37-1 significantly inhibits the proliferation of AML cells with or without Flt3-ITD mutation.

Development and Synthesis of Activity-based and Affinity-based Ubiquitin Probes / 生物化学与生物物理进展

Ubiquitination, a diverse post-translational modification, is carried out by enzymes including E1-activating enzymes, E2-conjugating enzymes, E3 ligases, and deubiquitinating enzymes (DUBs). Ubiquitin itself possesses 7 lysine residues and N-terminal methionine, allowing for the formation of polyubiquitin chains with different lengths and linkages. These chains exhibit various topologies that can be recognized by proteins containing ubiquitin-binding domain, thereby transmitting distinct cellular signals. To unravel the physiological mechanisms associated with ubiquitin, numerous ubiquitin probes have been developed. This review provides an overview of recent advancements in the field of ubiquitin probes, focusing on activity-based and affinity-based probes. Activity-based probes are designed to covalently bind to DUBs, E1s, or E3s, enabling the identification and characterization of these enzymes. Affinity-based probes, on the other hand, selectively bind to ubiquitin-binding domains, facilitating the identification of proteins that interact with ubiquitin. Moreover, this review comprehensively discusses the synthetic methodologies employed for the acquisition of ubiquitin probes. These includes meticulous discussions on the synthesis of individual monomeric modules, the establishment of isopeptide linkages, as well as the incorporation of reactive functional groups. Additionally, the review explores the emerging area of cell-penetrating ubiquitin probes and highlights their latest applications in living cells. These probes incorporate cell-penetrating peptides to enable their internalization into cells, allowing for direct visualization and manipulation of ubiquitin-modified proteins within their native environment. Overall, this review offers insights into the design, synthesis, and applications of ubiquitin probes, highlighting their significance in elucidating ubiquitin-mediated cellular processes.

The Roles of Deubiquitinases in Renal Cell Carcinoma / 生物化学与生物物理进展

Renal cell carcinoma (RCC) is the primary malignant neoplasm. The ubiquitin-proteasome system (UPS) is crucial to the control of protein level and regulation of physiological and pathological processes. Deubiquitinases (DUBs), key components of UPS, specifically removing ubiquitin chains from the target protein, have showed crucial roles for protein homeostasis and quality control by rigidly regulating the balance between ubiquitination and deubiquitination in normal physiology. Accumulating studies indicate that abnormal function DUBs is associated with the progression and metastasis of RCC. Depending on the substrates, some DUBs may suppress RCC while others promote. Herein, we review recent research advances in RCC-associated DUBs, describe their classification, functional roles, summarize the role and mechanisms of action of DUBs in RCC and discuss the potential of targeting DUBs for cancer treatment.

Role of post-translational modification of basic leucine zipper transcription factors in response to abiotic stresses in plants / 生物工程学报

Abiotic stresses substantially affect the growth and development of plants. Plants have evolved multiple strategies to cope with the environmental stresses, among which transcription factors play an important role in regulating the tolerance to abiotic stresses. Basic leucine zipper transcription factors (bZIP) are one of the largest gene families. The stability and activity of bZIP transcription factors could be regulated by different post-translational modifications (PTMs) in response to various intracellular or extracellular stresses. This paper introduces the structural feature and classification of bZIP transcription factors, followed by summarizing the PTMs of bZIP transcription factors, such as phosphorylation, ubiquitination and small ubiquitin-like modifier (SUMO) modification, in response to abiotic stresses. In addition, future perspectives were prospected, which may facilitate cultivating excellent stress-resistant crop varieties by regulating the PTMs of bZIP transcription factors.

Unveiling the clinical spectrum of relapsing polychondritis: insights into its pathogenesis, novel monogenic causes, and therapeutic strategies

Abstract Relapsing polychondritis is a rare multisystem disease involving cartilaginous and proteoglycan-rich structures. The diagnosis of this disease is mainly suggested by the presence of flares of inflammation of the cartilage, particularly in the ears, nose or respiratory tract, and more rarely, in the presence of other manifestations. The spectrum of clinical presentations may vary from intermittent episodes of painful and often disfiguring auricular and nasal chondritis to an occasional organ or even life-threatening manifestations such as lower airway collapse. There is a lack of awareness about this disease is mainly due to its rarity. In 2020, VEXAS (vacuoles, E1 enzyme, X-linked, autoinflammatory, somatic) syndrome, a novel autoinflammatory syndrome, was described. VEXAS syndrome is attributed to somatic mutations in methionine-41 of UBA1, the major E1 enzyme that initiates ubiquitylation. This new disease entity connects seemingly unrelated conditions: systemic inflammatory syndromes (relapsing chondritis, Sweet's syndrome, and neutrophilic dermatosis) and hematologic disorders (myelodysplastic syndrome or multiple myeloma). Therefore, this article reviews the current literature on both disease entities.

The role of SUMOylation in the protective mechanisms of therapeutic hypothermia on neonatal hypoxic-ischemic encephalopathy / 中国新生儿科杂志

Objective:To study the role of SUMOylation in the process of therapeutic hypothermia on neural stem cells (NSCs) in neonatal hypoxic-ischemic encephalopathy.Methods:SUMOylation is an essential post-translational modification involving small ubiquitin-like modifiers (SUMOs). Primary-cultured NSCs from mice were assigned into four groups: control group, hypoxia group, hypothermia group and hypoxia+hypothermia group. Western Blot was used to detect the protein levels of SUMO2/3, hypoxia-inducible factor-1α (HIF-1α), peroxisome proliferator-activated receptor γ coactivator factor 1α (PGC-1α) and octamer binding transcription factor 4 (Oct4). The diameters of NSCs were compared. ELISA was used to detect lactate dehydrogenase (LDH) level. Apoptosis was examined using flow cytometry. Immunofluorescence method was used to measure the differentiation of NSCs into neuronal cells.Results:Compared with the control group, the levels of SUMO2/3, HIF-1αand PGC-1α in NSCs of the hypoxia group increased 33%, 126% and 140%, respectively ( P<0.05). Compared with the control group, the levels of SUMO2/3 and PGC-1α in NSCs of the hypothermia group increased 52% and 536%, respectively ( P<0.05). Compared with the hypoxia group, the levels of SUMO2/3, HIF-1α, PGC-1α and Oct4 in the hypoxia+hypothermia group increased 44%, 40%, 230% and 59%, respectively ( P<0.05). The diameters of NSCs in hypoxia group, hypothermia group and hypoxia+hypothermia group were smaller than control group, and hypoxia+hypothermia group smaller than hypoxia group ( P<0.05). No significant differences existed in LDH levels between hypothermia group and control group ( P>0.05). LDH level in hypoxia+hypothermia group were significantly lower than hypoxia group ( P<0.05). No significant differences existed in the cell death rates between hypothermia group and control group ( P>0.05). The cell death rate in hypoxia+hypothermia group was significantly lower than hypoxia group ( P<0.05). Compared with the control group, the expressions of Nestin in both hypoxia group and hypothermia group were increased, but neuron specific enolase (NSE) were decreased ( P<0.05). Compared with hypoxia group and hypothermia group, the level of Nestin in hypoxia+hypothermia group was further increased, while NSE was further decreased ( P<0.05). Conclusions:Therapeutic hypothermia may increase the tolerance of NSCs to hypoxia by enhancing SUMO modification of proteins, providing theoretical basis for the treatment of hypoxic-ischemic encephalopathy with therapeutic hypothermia.

Elevated phosphorylated ubiquitin level elicits neuro-degeneration by aggregating the decline of ubiquitin-dependent proteasomal degradation / 中国药理学与毒理学杂志

OBJECTIVE To determine the roles of phosphorylated ubiquitin(pUb)on ubiquitin-dependent proteasomal(UPS)degradation activity,and the roles of pUb on neurodegeneration.METHODS We use PTEN induced kinase 1(PINK1)to phosphorylate ubiquitin.The Ub/S65A cannot be phosphorylated by PINK1,and was used to antagonize the roles of pUb.The Ub/S65E was used to mimic the roles of pUb.The roles of pUb on UPS degradation activity were determined by immunoflu-orescence,Western blot and TIRF microscope at cellular and protein level.The roles of pUb on neurodegeneration were determined by behavior tests,immunofluorescence,Golgi staining,TEM,Western blot and proteomics sacle in mouse.RESULTS The level of soluble PINK1(sPINK1)and pUb increased in the neurons of aged mouse brain,and in the cells upon the administration of MG132,a proteasome inhibitor.The elevation of sPINK1 and pUb was accompanied by protein aggregation upon aging or the proteasomal inhibition.The pink1 knockout alleviated proteasomal inhibition induced protein aggregation and association of ubiquitinated proteins with proteasome.The over-expression of sPINK1 increased pUb level in hippocampal neuron,which chronically induced protein aggregation,mitochondrial damage and damage the structure of neuronal spines.Such neuronal injury lead to cognitive impairment of mice.The roles of sPINK1 was reversed by co-expression with Ub/S65A,and was mimic by over-expression with Ub/S65E.CONCLUSION The phosphorylation of ubiquitin aggravates UPS degrada-tion,and accelerates neuronal degeneration upon the decline of proteasomal degradation in aging and age-related neuronal diseases.

Research progress of tripartite motif-containing protein 28 in tumors / 中国医师杂志

Tripartite motif-containing protein 28 is a kind of macromolecular protein with E3 ubiquitin ligase, which belongs to an important member of the TRIM protein family. As a new molecular biomarker, it has attracted wide attention. TRIM28 is highly expressed in many kinds of malignant tumors, which is closely related to clinicopathological features, and is also involved in biological behaviors such as proliferation, apoptosis, migration and invasion of tumor cells. TRIM28 may be a potential marker and therapeutic target for clinical diagnosis and prognosis of tumors. This study reviews the structure and biological function of TRIM28, its relationship with malignant tumors and the molecular mechanism of signal transduction pathway.

Study on the inhibitory effect of UBE2T on radiosensitivity of lung adenocarcinoma / 中华放射肿瘤学杂志

Objective:To investigate the effect of ubiquitin binding enzyme 2T (UBE2T) on the radiosensitivity of lung adenocarcinoma and unravel its possible mechanism.Methods:A total of 45 patients pathologically diagnosed with different stages of lung adenocarcinoma and treated with radiotherapy in the Second Affiliated Hospital of Zunyi Medical University from March, 2019 to December, 2021 were enrolled, and the efficacy was evaluated according to response evaluation criteria in solid tumors (RECIST1.1). All patients were divided into radiosensitive group ( n=25) and radioresistant group ( n=20). Radiosensitive group was complete remission (CR)+partial remission (PR), and radioresistant group was stable disease (SD) + progression disease (PD). Immunohistochemistry (IHC) was used to calculate the score based on the staining intensity and the number of positive cells. Chi-square test was combined to analyze the correlation between the expression level of UBE2T in paraffin specimens of lung adenocarcinoma patients and the radiosensitivity of patients. Lentivirus UBE2T-interfered (UBE2Tsh) A549 and UBE2T-overexpressed SPC-A-1 lung adenocarcinoma cells and their respective controls were constructed for irradiation and colony formation assay. The survivor fraction curve was fitted by single-hit multi-target model. The DNA double-strand break (DSB) marker γH2AX foci were detected by immunofluorescence (IF). The expression levels of UBE2T, γH 2AX and Rad51 proteins were detected by Western blot. Cell cycle and apoptosis rate of A549 were determined by flow cytometry. Binary variables were statistically analyzed by Fisher's exact probability method and measurement data were assessed by t-test. Results:High-expression level of UBE2T was correlated with the radiosensitivity of lung adenocarcinoma patients ( P<0.05). UBE2Tsh improved the radiosensitivity of A549 lung adenocarcinoma cells, and the sensitizing enhancement ratio (SER) was 1.795. UBE2T overexpression decreased the radiosensitivity of SPC-A-1 lung adenocarcinoma cells with an SER of 0.293. γH2AX foci number per cell were significantly increased in UBE2Tsh A549 cells after irradiation ( P<0.01) . Compared with the control group, the expression level of γH2AX protein was up-regulated ( P<0.01)and that of Rad51 protein was down-regulated in UBE2Tsh A549 cells after radiation ( P<0.001). Compared with the control group, the expression level of γH2AX protein was down-regulated ( P<0.05) and that of Rad51 protein was up-regulated in UBE2T overexpressed SPC-A-1 cells ( P<0.001). The proportion of UBE2Tsh A549 cells in G 2 phase was decreased ( P<0.01) and cell apoptosis was increased ( P<0.001). Conclusions:UBE2T might promote the radioresistance of lung adenocarcinoma cells by enhancing DNA DSB repair induced by radiotherapy, inducing cell cycle G 2 phase arrest, and reducing cell apoptosis.

Effect of selective cerebral mild hypothermia on SUMO2/3 modification of Drp1 in a rat model of cerebral ischemia-reperfusion / 中华麻醉学杂志

Objective:To evaluate the effect of selective cerebral mild hypothermia on small ubiquitin-like modifier 2/3 (SUMO2/3) modification of dynamin-related protein 1 (Drp1) in a rat model of cerebral ischemia-reperfusion (I/R).Methods:Sixty clean-grade healthy male Sprague-Dawley rats, aged 6-8 weeks, weighing 240-260 g, were divided into 4 groups ( n=15 each) using a random number table method: sham operation group (S group), cerebral I/R group (I/R group), selective cerebral mild hypothermia group (HT group) and normal temperature group (NT group). The operation was performed under the monitoring of cerebral temperature and rectal temperature.Only the cervical blood vessels were exposed in S group, while focal cerebral I/R was induced by 2 h middle cerebral artery occlusion (MCAO) followed by 24 h reperfusion in anesthetized animals in the other three groups.In HT group and NT group, 4 and 37 ℃ normal saline was perfused through the left internal carotid artery at a rate of 80 ml·kg -1·h -1 for 15 min, respectively. Modified neurological severity score (mNSS) was assessed at 24 h of reperfusion. Then the rats were sacrificed under deep anesthesia, brains were removed, brain tissues were obtained for determination of the percentage of cerebral infarct size (by TTC staining), and the ischemic penumbra tissues in the cerebral cortex were removed for examination of the ultra-structural changes of mitochondria (with a transmission electron microscope) and for determination of the SUMO2/3 modification of Drp1 (by CO-IP), expression of total Drp1 (T-Drp1) and total cytochrome c (T-Cytc) (by Western blot), and expression of mitochondrial outer membrane Drp1 (M-Drp1) and cytoplasmic Cytc (C-Cytc) (by Western blot) after isolation of mitochondria and cytoplasm. Results:Compared with S group, the mNSS and percentage of cerebral infarct size were significantly increased, the expression of M-Drp1, T-Drp1, C-Cytc and T-Cytc was up-regulated, and SUMO2/3 modification of Drp1 in ischemic penumbra area was increased ( P<0.05), the fragmentation of mitochondria was aggravated, and cristae rupture and vacuolation were obvious in the other three groups. Compared with I/R group, the mNSS and percentage of cerebral infarct size were significantly decreased, the expression of M-Drp1, T-Drp1, C-Cytc and T-Cytc was down-regulated, SUMO2/3 modification of Drp1 was increased ( P<0.05), the fragmentation of mitochondria was significantly attenuated, and cristae rupture and vacuolation were weakened in HT group. There were no significant differences in these detection parameters between NT group and I/R group ( P>0.05). Conclusions:The mechanism by which selective cerebral mild hypothermia alleviates the cerebral I/R injury is related to increased SUMO2/3 modification of Drp1, decreased binding of Drp1 to mitochondrial outer membrane, and reduced mitochondrial excessive fission in rats.

Role of PIAS-regulated SUMOylation of PPARγ in endogenous protective mechanism against endotoxin-induced acute lung injury in mice / 中华麻醉学杂志

Objective:To evaluate the role of small ubiquitin-associated modifier (SUMO) E3 ligase (PIAS)-regulated SUMOylation of peroxisome proliferator-activated receptor γ (PPARγ) in the endogenous protective mechanism against endotoxin-induced acute lung injury (ALI) in mice.Methods:Experiment Ⅰ Twenty-four clean-grade wild type male C57BL/6 mice, aged 6-8 weeks, weighing 18-22 g, were divided into 4 groups ( n=6 each) using a random number table method: control group (C group), ALI group, ALI+ PPARγ inducer TZD group (ALI+ T group) and ALI+ TZD+ SUMOylation inhibitor anacardic acid group (ALI+ T+ A group). Lipopolysaccharide (LPS) 15 mg/kg was injected into the tail vein to develop the ALI model. In ALI+ T+ A group, anacardic acid 5 mg/kg was intraperitoneally injected at 1 h before LPS administration. In ALI+ T group and ALI+ T+ A group, TZD 50 mg/kg was intraperitoneally injected at 30 min before LPS administration. The mice were sacrificed at 12 h after LPS administration, and the lung tissues were obtained to examine the pathological changes which were scored and to determine the wet/dry (W/D) weight ratio, and expression of PIAS1, PIAS2, PIAS3 and PIASy protein and mRNA (by Western blot or polymerase chain reaction). Experiment Ⅱ Mouse alveolar macrophages (MH-S cells) were cultured in vitro and divided into 4 groups ( n=5 each) using a random number table method: control group (C group), LPS group, LPS+ PIAS2 siRNA group (L+ P group) and LPS+ Con siRNA group (L+ C group). Cells were routinely cultured in group C. Cells were stimulated with 10 μg/ml LPS to develop the model of endotoxin challenge. PIAS2 siRNA 50 nmol/L and Con siRNA 50 nmol/L were transfected at 48 h before LPS was added in L+ P group and L+ C group, respectively. The cells were collected at 24 h of incubation with LPS to determine the cell viability, levels of M1 and M2 alveolar macrophages (by flow cytometry), expression of PIAS2 and PPARγ (by Western blot), co-expression of PPARγ-SUMO1 (by immunoprecipitation) and expression of tumor necrosis factor-alpha (TNF-α) and interleukin-10 (IL-10) mRNA (by polymerase chain reaction). The ratio of M1/M2 was calculated. Results:Experiment Ⅰ Compared with C group, the lung injury scores and W/D ratio were significantly increased, and the expression of PIAS2 protein and mRNA was up-regulated in the other three groups ( P<0.05). Compared with ALI group, the lung injury scores and W/D ratio were significantly decreased, and the expression of PIAS2 protein and mRNA was up-regulated in ALI+ T group and ALI+ T+ A group ( P<0.05). Compared with ALI+ T group, the lung injury scores and W/D ratio were significantly increased, and the expression of PIAS2 protein and mRNA was down-regulated in ALI+ T+ A group ( P<0.05). There was no significant difference in the expression of PIAS1, PIAS3 and PIASy protein and mRNA in lung tissues among the four groups ( P>0.05). Experiment Ⅱ Compared with C group, the cell viability was significantly decreased, the expression of PPARγ and co-expression of PPARγ-SUMO1 was up-regulated, the levels of M1 and M2 macrophages and M1/M2 ratio were increased, the expression of TNF-α mRNA was up-regulated, and the expression of IL-10 mRNA was down-regulated in the other three groups, and PIAS2 expression was significantly up-regulated in L group and L+ C group ( P<0.05). Compared with L group, the cell viability was significantly decreased, the expression of PIAS2 and PPARγ and PPARγ-SUMO1 co-expression were down-regulated, the M1 macrophage level and M1/M2 ratio were increased, TNF-α mRNA expression was up-regulated, and the expression of IL-10 mRNA was down-regulated in L+ P group ( P<0.05), and no significant change was found in the parameters mentioned above in L+ C group ( P>0.05). Compared with L+ C group, the cell viability was significantly decreased, the expression of PIAS2 and PPARγ and co-expression of PPARγ-SUMO1 were down-regulated, the level of M1 alveolar macrophages and M1/M2 ratio were increased, the expression of TNF-α mRNA was down-regulated, and the expression of IL-10 mRNA was up-regulated in L+ P group ( P<0.05). Conclusions:PIAS2-regulated SUMOylation of PPARγ is the endogenous protective mechanism against endotoxin-induced ALI in mice, which may be related to inhibition of macrophage polarization into M1 type and alleviation of inflammatory responses.