Small ubiquitin-like modifier(SUMO)ylation is a key posttranslational modification mechanism that controls the function of a plethora of proteins and biological processes. Given its central regulatory role, it is not ...Small ubiquitin-like modifier(SUMO)ylation is a key posttranslational modification mechanism that controls the function of a plethora of proteins and biological processes. Given its central regulatory role, it is not surprising that it is widely exploited by viruses. A number of viral proteins are known to modify and/or be modified by the SUMOylation system to exert their function, to create a cellular environment more favorable for virus survival and propagation, and to prevent host antiviral responses. Since the SUMO pathway is a multi-step cascade, viral proteins engage with it at many levels, to advance and favor each stage of a typical infection cycle: replication, viral assembly and immune evasion. Here we review the current knowledge on the interplay between the host SUMO system and viral lifecycle.展开更多
Background Non-small cell lung cancer （NSCLC） is one of the most common malignant tumors.Despite the advances in therapy over the years,its mortality remains high.The aim of this study was to evaluate the expression...Background Non-small cell lung cancer （NSCLC） is one of the most common malignant tumors.Despite the advances in therapy over the years,its mortality remains high.The aim of this study was to evaluate the expression of small ubiquitin-like modifier （SUMO） proteases 1 （SENP1） in NSCLC tissues and its role in the regulation of vascular endothelial growth factor （VEGF） expression.We also investigated the association between the expression level of SENP1 and the clinicopathological features and survival of the patients.Methods A SENP1 small interfering RNA （siRNA） was constructed and transfected into the NSCLC cells.VEGF gene expression was analyzed by real-time polymerase chain reaction （RT-PCR）.Immunohistochemistry staining was used to assess the expression of SENP1 in 100 NSCLC patients and its association with the clinicopathological features and survival was analyzed.Results VEGF expression was significantly higher in NSCLC tissues than in normal lung tissues.Inhibition of SENP1 by siRNA was associated with decreased VEGF expression.SENP1 was over-expressed in 55 of the 100 NSCLC samples （55％） and was associated with a moderate and low histological tumor grade （3.6％,38.2％,and 58.2％ in high,moderate and low differentiated tumors,respectively,P=0.046）,higher T stage （10.9％ in T1,and 89.1％ in T2 and T3 tumor samples,P ＜0.001）and TNM stage （10.9％ in stage Ⅰ,and 89.1％ in stages Ⅱ and Ⅲ tumor samples,P ＜0.001）.The rate of lymph node metastasis was significantly higher in the SENP1 over-expression group （76.4％） than that in the SENP1 low expression group （33.3％,P ＜0.001）.Sixty three patients received postoperative chemotherapy,including 34 with SENP1 over-expression and 29 with SENP1 low expression.Among the 34 patients with SENP1 over-expression,22 （64.7％） patients developed recurrence or metastasis,significantly higher than those in the low expression group 27.6％ （8/29） （P=0.005）.Multivariate Cox regression analysis showed展开更多
Ubiquitin-fold modifier 1（UFM1） is one of the newly-identified ubiquitin-like proteins.Similar to ubiquitin,UFM1 is conjugated to its target proteins by a three-step enzymatic reaction.The UFM1-activating enzyme,ubi...Ubiquitin-fold modifier 1（UFM1） is one of the newly-identified ubiquitin-like proteins.Similar to ubiquitin,UFM1 is conjugated to its target proteins by a three-step enzymatic reaction.The UFM1-activating enzyme,ubiquitin-like modifier-activating enzyme 5（UBA5）,serves as the E1 to activate UFM1;UFM1-conjugating enzyme 1（UFC1） acts as the E2 to transfer the activated UFM1 to the active site of the E2;and the UFM1-specific ligase 1（UFL1） acts as the E3 to recognize its substrate,transfer,and ligate the UFM1 from E2 to the substrate.This process is called ufmylation.UFM1 chains can be cleaved from its target proteins by UFM1-specific proteases（Uf SPs）,suggesting that the ufmylation modification is reversible.UFM1 cascade is conserved among nearly all of the eukaryotic organisms,but not in yeast,and associated with several cellular activities including the endoplasmic reticulum stress response and hematopoiesis.Furthermore,the UFM1 cascade is closely related to a series of human diseases.In this review,we summarize the molecular details of this reversible modification process,the recent progress of its functional studies,as well as its implication in tumorigenesis and potential therapeutic targets for cancer.展开更多
Small ubiquitin-like modifier （SUMO） conjugation affects a broad range of processes in plants, including growth, flower initiation, pathogen defense, and responses to abiotic stress. Here, we investigate in vivo and...Small ubiquitin-like modifier （SUMO） conjugation affects a broad range of processes in plants, including growth, flower initiation, pathogen defense, and responses to abiotic stress. Here, we investigate in vivo and in vitro a SUMO conjugating enzyme with a Cys to Ser change in the active site, and show that it has a dominant negative effect. In planta expression significantly perturbs normal development, leading to growth retardation, early flowering and gene expression changes. We suggest that the mutant protein can serve as a probe to investigate sumoylation, also in plants for which poor genetic infrastructure precludes analysis via loss-of-function mutants.展开更多
TANK-binding kinase 1(TBK1)is an important enzyme in the regulation of cellular antiviral effects.TBK1 regulates the activity of the interferon regulatory factors IRF3 and IRF7,thereby playing a key role in type I int...TANK-binding kinase 1(TBK1)is an important enzyme in the regulation of cellular antiviral effects.TBK1 regulates the activity of the interferon regulatory factors IRF3 and IRF7,thereby playing a key role in type I interferon(IFN)signaling pathways.The structure of TBK1 consists of an N-terminal kinase domain,a middle ubiquitin-like domain(ULD),and a C-terminal elongated helical domain.It has been reported that the ULD of TBK1 regulates kinase activity,playing an important role in signaling and mediating interactions with other molecules in the IFN pathway.In this study,we present the crystal structure of the ULD of human TBK1 and identify several con-served residues by multiple sequence alignment.We found that a hydrophobic patch in TBK1,containing residues Leu316,Ile353,and Val382,corresponding to the“Ile44 hydrophobic patch”observed in ubiquitin,was conserved in TBK1,IκB kinase epsilon(IKKε/IKKi),IκB kinase alpha(IKKα),and IκB kinase beta(IKKβ).In com-parison with the structure of the IKKβULD domain of Xenopus laevis,we speculate that the Ile44 hydrophobic patch of TBK1 is present in an intramolecular binding surface between ULD and the C-terminal elongated heli-ces.The varying surface charge distributions in the ULD domains of IKK and IKK-related kinases may be relevant to their specificity for specific partners.展开更多
Background The genes encoding adiponectin receptor 1 （ADIPOR1） and small ubiquitin-like modifier 4 （SUM04） have been linked to anti-atherogenic effects, but little is known about whether polymorphisms in the two g...Background The genes encoding adiponectin receptor 1 （ADIPOR1） and small ubiquitin-like modifier 4 （SUM04） have been linked to anti-atherogenic effects, but little is known about whether polymorphisms in the two genes, acting separately or interacting, affect risk of coronary artery disease （CAD） without diabetes. Methods We genotyped 200 CAD patients without diabetes and 200 controls without CAD or diabetes at three single-nucleotide polymorphisms （SNPs） in ADIPOR1 and one SNP in SUM04, which were chosen based on previous studies. Potential associations were also explored between these SNPs and clinical characteristics of CAD without diabetes. Results Risk alleles at three SNPs inADIPOR1 （rs7539542-G, rs7514221-C and rs3737884-G） and the G allele at SNP rs237025 in SUM04 significantly increased risk of CAD without diabetes, with ORs ranging from 1.79 to 4.44. Carriers of any of these four risk alleles showed similar adverse clinical characteristics. Compared with individuals with a CC or GC genotype, those with a GG genotype at rs3737884 were at significantly higher risk of CAD that affected the left anterior descending coronary artery （OR： 6.77, P = 0.009）, the right coronary artery （OR： 4.81, P = 0.028） or a relatively large number of vessels （P = 0.04）. Individuals carrying a risk allele at one or more of the three SNPs in ADIPOR1 as well as a risk allele at the SNP in SUM04 were at significantly higher risk of CAD without diabetes than individuals not carrying any risk alleles （OR： 5.82, 95% CI： 1.23-27.7, P= 0.013）. Conelusions SNPs in ADIPORl and SUMO4 are associated with elevated risk of CAD without diabetes, and SNPs in the two genes may interact to jointly affect disease risk.展开更多
BACKGROUND Colorectal cancer(CRC) is a common malignancy of the gastrointestinal tract. The worldwide mortality rate of CRC is about one half of its morbidity. Ubiquitin is a key regulatory factor in the cell cycle an...BACKGROUND Colorectal cancer(CRC) is a common malignancy of the gastrointestinal tract. The worldwide mortality rate of CRC is about one half of its morbidity. Ubiquitin is a key regulatory factor in the cell cycle and widely exists in eukaryotes. Human leukocyte antigen F-associated transcript 10(FAT10), known as diubiquitin, is an 18 kDa protein with 29% and 36% homology with the N and C termini of ubiquitin. The function of FAT10 has not been fully elucidated, and some studies have shown that it plays an important role in various cell processes.AIM To examine FAT10 expression and to analyze the relationship between FAT10 expression and the clinicopathological parameters of CRC.METHODS FAT10 expression in 61 cases of CRC and para-cancer colorectal tissues was measured by immunohistochemistry and Western blotting. The relationship between FAT10 expression and clinicopathological parameters of CRC was statistically analyzed.RESULTS Immunohistochemical analysis showed that the positive rate of FAT10 expression in CRC(63.93%) was significantly higher than that in tumor-adjacent tissues(9.84%, P < 0.05) and normal colorectal mucosal tissue(1.64%, P < 0.05). Western blotting also indicated that FAT10 expression was significantly higher in CRC than in tumor-adjacent tissue(P < 0.05). FAT10 expression was closely associated with clinical stage and lymphatic spread of CRC. FAT10 expression also positively correlated with p53 expression.CONCLUSION FAT10 expression is highly upregulated in CRC. FAT10 expression is closely associated with clinical stage and lymphatic spread of CRC.展开更多
Small ubiquitin-like modifier(SUMO)-conjugating enzymes are involved in post-translational regulatory processes in eukaryotes, including the conjugation of SUMO peptides to protein substrate(SUMOylation). SUMOylation ...Small ubiquitin-like modifier(SUMO)-conjugating enzymes are involved in post-translational regulatory processes in eukaryotes, including the conjugation of SUMO peptides to protein substrate(SUMOylation). SUMOylation plays an important role in improving plant tolerance to abiotic stress such as salt, drought, heat and cold. Herein, we reported the isolation of OsSCE1(LOC_Os10 g39120) gene encoding a SUMO-conjugating enzyme from rice(Oryza sativa cv. Nipponbare) and its functional validation in response to drought stress. The E2 enzyme, Os SCE1, is one of three key enzymes involved in the conjugation of SUMO to its target proteins. Activated SUMO is transferred to the cysteine of an E2 enzyme and then to the target lysine residue of the substrate, with or without the help of an E3 SUMO ligase. Expression of OsSCE1 was strongly induced by polyethylene glycol 6000(PEG6000) treatment, which suggested OsSCE1 may be involved in the drought stress response. Overexpression of OsSCE1(OsSCE1-OX) in Nipponbare reduced the tolerance to drought stress. Conversely, the drought tolerance was slightly improved by the knockdown of OsSCE1(OsSCE1-KD). These results were further supported by measurement of proline content in OsSCE1-OX and OsSCE1-KD transgenic lines under induced drought stress, which showed OsSCE1-KD transgenic lines accumulated higher proline content than the wild type, whereas OsSCE1-OX line had lower proline content than the wild type. These findings suggested OsSCE1 may play a role as a negative regulator in response to drought stress in rice.展开更多
In order to investigate the effect of small ubiquitin-like modifier-1 (SUMO-1) on the p53-induced HepG2 cell apoptosis, HepG2 cells were transfected by recombinant plasmids as pwtp53, pMDM2 and pSUMO-1 respectively. W...In order to investigate the effect of small ubiquitin-like modifier-1 (SUMO-1) on the p53-induced HepG2 cell apoptosis, HepG2 cells were transfected by recombinant plasmids as pwtp53, pMDM2 and pSUMO-1 respectively. Western blot was employed to detect the protein expression of the transfected recombinant plasmids and the rate of apoptosis was measured by flow cytometry. The results showed that in cells transfected with pwtp53 and pwtp53+pSUMO-1, the apoptosis rate was (16.79±1.62) % and (18.15±1.36) % respectively, while transfected with pwtp53+pMDM2, the rate was decreased to (5.17±1.23) %. The apoptosis rate was (14.06±1.84) % in the cells transfected with pwtp53+pMDM2+pSUMO-1, significantly higher than that in the cells Transfected with pwtp53+pMDM2 (P<0.01). The apoptosis rates in the cells were all less than 2 % and had no significant difference among the groups. It was suggested that in the HepG2 cells, SUMO-1 can increase the apoptosis induced by wild-type p53 through binding to p53 protein, post-translational modification and inhibiting the p53 degradation by MDM2.展开更多
目的:探讨UHRF1(Ubiquitin-like,containing PHD and RING finger domains 1)在肝细胞肝癌(hepatocellular carcinoma,HCC)中的表达及其与临床病理特征的关系。方法:采用免疫组织化学方法检测556例HCC组织及其癌旁组织中UHRF1的表达,分...目的:探讨UHRF1(Ubiquitin-like,containing PHD and RING finger domains 1)在肝细胞肝癌(hepatocellular carcinoma,HCC)中的表达及其与临床病理特征的关系。方法:采用免疫组织化学方法检测556例HCC组织及其癌旁组织中UHRF1的表达,分析其与HCC患者临床病理特征的关系。结果:免疫组织化学结果显示,UHRF1蛋白阳性表达定位于HCC细胞核,UHRF1蛋白在HCC组织中的表达显著高于癌旁组织。HCC组织中UHRF1蛋白阳性表达率为59%,其表达与肿瘤大小(P<0.01)、肿瘤分化(P<0.05)和微血管侵犯(P<0.01)相关。结论:HCC中UHRF1的表达与其恶性表型相关,UHRF1可能参与HCC的侵袭和转移。展开更多
Different from canonical ubiquitin-like proteins, Hub1 does not form covalent conjugates with substrates but binds proteins noncovalently. In Socchoromyces cerevisioe, Hub1 associates with spUceosomes and mediates alt...Different from canonical ubiquitin-like proteins, Hub1 does not form covalent conjugates with substrates but binds proteins noncovalently. In Socchoromyces cerevisioe, Hub1 associates with spUceosomes and mediates alternative splicing of SRCI, without affecting pre-mRNA splicing generaity. Human Hub1 is highty similar to its yeast homotog, but its cellular function remains largely unexplored. Here, we show that human Hub1 binds to the spliceosomal protein Snu66 as in yeast; however, unlike its 5. cerevisioe homolos, human Hub1 is essential for viability. Prolonged in vivo depletion of human Hub1 leads to various cellular defects, including splicing speckle abnormalities, partial nuclear retention of mRNAs, mitotic catastrophe, and consequently cell death by apoptosis. Early consequences of Hub1 depletion are severe splicing defects, however, only for specific splice sites leading to exon skipping and intron retention. Thus, the ubiquitin-iike protein Hub1 is not a canonlcal spliceosomal factor needed generally for splicing, but rather a modulator of spliceosome performance and facilitator of alternative splicing.展开更多
Radiation sensitivity proteins-23 （RAD23） are DNA repair factors participate in the ubiquitin/proteasome system （UPS）. Although the genome-wide analysis of RAD23 family members has been conducted in some species, ...Radiation sensitivity proteins-23 （RAD23） are DNA repair factors participate in the ubiquitin/proteasome system （UPS）. Although the genome-wide analysis of RAD23 family members has been conducted in some species, little is known about RAD23 genes in apple （Malusxdomestica Borkh.）. We analyzed this gene family in M. domestica in terms of genomic locations, protein and promoter structures, and expressions in response to stresses. Various members showed a ubiqui- tous pattern of expression in all selected apple parts. Their expressions were altered under chilling, heat, and hydrogen peroxide treatments, as well as abscisic acid （ABA） treatment and water deficiency, suggesting their possible roles in plant stress responses. These results provide essential information about RAD23 genes in apple and will contribute to further functional studies.展开更多
AIM To investigate the function and mechanism of ubiquitinlike modifier activating enzyme 2(Uba2) in progression of gastric cancer(GC) cells.METHODS Uba2 level in patients with GC was analyzed by Western blotting and ...AIM To investigate the function and mechanism of ubiquitinlike modifier activating enzyme 2(Uba2) in progression of gastric cancer(GC) cells.METHODS Uba2 level in patients with GC was analyzed by Western blotting and immunohistochemistry. MTT and colony formation assays were performed to examine cell proliferation.Flow cytometry was used for cell cycle analysis.Wound healing and Transwell assays were conducted to examine the effects of Uba2 on migration and invasion.Expression levels of cell cycle-related proteins, epithelial-mesenchymal transition(EMT) biomarkers, and involvement of the Wnt/β-catenin pathway was assessed by Western blotting. Activation of the Wnt/β-catenin pathway was confirmed by luciferase assay.RESULTS Uba2 expression was higher in GC than in normal tissues.Increased Uba2 expression was correlated with tissue differentiation, Lauren's classification, vascular invasion,and TNM stage, as determined by the analysis of 100 GC cases(P < 0.05). Knock-down of Uba2 inhibited GC cell proliferation, induced cell cycle arrest, and altered expression of cyclin D1, P21, P27, and Bcl-2, while upregulation of Uba2 showed the opposite effects. The wound healing and Transwell assays showed that Uba2 promoted GC cell migration and invasion. Western blotting revealed alterations in EMT biomarkers, suggesting the role of Uba2 in EMT. Furthermore, the luciferase reporter assay indicated the involvement of the Wnt/β-catenin signaling pathway as a possible modulator of Uba2 oncogenic functions.CONCLUSION Uba2 plays a vital role in GC cell migration and invasion,possibly by regulating the Wnt/β-catenin signaling pathway and EMT.展开更多
We identified a novel ubiquitin-like molecule DULP from human dendritic cells. DULP contains a domain that shares 26% identity and 34% similarity with ubiquitin, and it possesses the corresponding Ile-44 hydrophobic p...We identified a novel ubiquitin-like molecule DULP from human dendritic cells. DULP contains a domain that shares 26% identity and 34% similarity with ubiquitin, and it possesses the corresponding Ile-44 hydrophobic patch used by mono- or poly-ubiquitin to interact with a ubiquitin-interaction motif （UIM） or ubiquitin-associated domain （UBA）. Lysine residue corresponding to 6 of ubiquitin, which is involved in the formation of a multi-ubiquitin chain that can bind proteasomal subunit Rpn10/S5a, is also conserved in its ubiquitin-homology domain. However, DULP does not possess the highly conserved C-terminus Gly-Gly required for ubiquitin conjugation or the Lys-48 required for the formation of polyubiquitin chain to target substrates for degradation, suggesting it might be a novel ubiquitin-domain protein （UDP）. DULP was found widely expressed in many cells and the ubiquitin-homology domain was not cleaved. We also confirmed that DULP expression was enriched in the nucleus and much weaker in the cytosol. Besides, we found that overexpression of DULP in 293T cells induced apoptosis, which might not be associated with the mitochondrial or proteasome pathway, with the specific mechanism remain unclear. Further investigations are needed to identify the precise biological functions of DULP. Cellular ＆ Molecular Immunology.展开更多
Small ubiquitin-like modifiers(SUMOs)are protein modifiers that can form polymeric chains.They are important signals in cellular processes,and their study and profiling require the development of molecular tools.Herei...Small ubiquitin-like modifiers(SUMOs)are protein modifiers that can form polymeric chains.They are important signals in cellular processes,and their study and profiling require the development of molecular tools.Herein,the authors have reported an efficient chemical protein synthesis approach for the generation of dimeric SUMO-2-based photoaffinity probes through the ligation of four readily synthesizable peptides.Proteomic studies using this diSUMO-2 probe on HeLa cell nuclear lysate found it to capture a significantly different selection of proteins compared with its monoSUMO counterparts.This resulted in the identification of several previously unknown SUMO chain-specific interacting proteins such as 40S ribosomal protein S3,which showed a significantly higher affinity for polySUMO chains than monomeric SUMO.Collectively,these results emphasize the need to develop SUMO chain-based probes in other species,and to shed light on the important role of polySUMOylation in diseases.展开更多
SRY-related HMG-box(Sox) transcription factors are known to regulate central nervous system development and are involved in several neurological diseases.Post-translational modification of Sox proteins is known to alt...SRY-related HMG-box(Sox) transcription factors are known to regulate central nervous system development and are involved in several neurological diseases.Post-translational modification of Sox proteins is known to alter their functions in the central nervous system.Among the different types of post-translational modification,small ubiquitin-like modifier(SUMO) modification of Sox proteins has been shown to modify their transcriptional activity.Here,we review the mechanisms of three Sox proteins in neuronal development and disease,along with their transcriptional changes under SUMOylation.Across three species,lysine is the conserved residue for SUMOylation.In Drosophila,SUMOylation of Sox N plays a repressive role in transcriptional activity,which impairs central nervous system development.However,de SUMOylation of Sox E and Sox11 plays neuroprotective roles,which promote neural crest precursor formation in Xenopus and retinal ganglion cell differentiation as well as axon regeneration in the rodent.We further discuss a potential translational therapy by SUMO site modification using AAV gene transduction and Clustered regularly interspaced short palindromic repeats-Cas9 technology.Understanding the underlying mechanisms of Sox SUMOylation,especially in the rodent system,may provide a therapeutic strategy to address issues associated with neuronal development and neurodegeneration.展开更多
文摘Small ubiquitin-like modifier(SUMO)ylation is a key posttranslational modification mechanism that controls the function of a plethora of proteins and biological processes. Given its central regulatory role, it is not surprising that it is widely exploited by viruses. A number of viral proteins are known to modify and/or be modified by the SUMOylation system to exert their function, to create a cellular environment more favorable for virus survival and propagation, and to prevent host antiviral responses. Since the SUMO pathway is a multi-step cascade, viral proteins engage with it at many levels, to advance and favor each stage of a typical infection cycle: replication, viral assembly and immune evasion. Here we review the current knowledge on the interplay between the host SUMO system and viral lifecycle.
文摘Background Non-small cell lung cancer （NSCLC） is one of the most common malignant tumors.Despite the advances in therapy over the years,its mortality remains high.The aim of this study was to evaluate the expression of small ubiquitin-like modifier （SUMO） proteases 1 （SENP1） in NSCLC tissues and its role in the regulation of vascular endothelial growth factor （VEGF） expression.We also investigated the association between the expression level of SENP1 and the clinicopathological features and survival of the patients.Methods A SENP1 small interfering RNA （siRNA） was constructed and transfected into the NSCLC cells.VEGF gene expression was analyzed by real-time polymerase chain reaction （RT-PCR）.Immunohistochemistry staining was used to assess the expression of SENP1 in 100 NSCLC patients and its association with the clinicopathological features and survival was analyzed.Results VEGF expression was significantly higher in NSCLC tissues than in normal lung tissues.Inhibition of SENP1 by siRNA was associated with decreased VEGF expression.SENP1 was over-expressed in 55 of the 100 NSCLC samples （55％） and was associated with a moderate and low histological tumor grade （3.6％,38.2％,and 58.2％ in high,moderate and low differentiated tumors,respectively,P=0.046）,higher T stage （10.9％ in T1,and 89.1％ in T2 and T3 tumor samples,P ＜0.001）and TNM stage （10.9％ in stage Ⅰ,and 89.1％ in stages Ⅱ and Ⅲ tumor samples,P ＜0.001）.The rate of lymph node metastasis was significantly higher in the SENP1 over-expression group （76.4％） than that in the SENP1 low expression group （33.3％,P ＜0.001）.Sixty three patients received postoperative chemotherapy,including 34 with SENP1 over-expression and 29 with SENP1 low expression.Among the 34 patients with SENP1 over-expression,22 （64.7％） patients developed recurrence or metastasis,significantly higher than those in the low expression group 27.6％ （8/29） （P=0.005）.Multivariate Cox regression analysis showed
基金supported by the National Natural Science Foundation of China (NSFCGrant Nos.31530016 and 31461143012)+2 种基金the National Basic Research Program of China (973 ProgramGrant Nos.2013CB911002 and 2015CB910601)the Scientific Research Base Development Program of the Beijing Municipal Commission of Education,China to XX
文摘Ubiquitin-fold modifier 1（UFM1） is one of the newly-identified ubiquitin-like proteins.Similar to ubiquitin,UFM1 is conjugated to its target proteins by a three-step enzymatic reaction.The UFM1-activating enzyme,ubiquitin-like modifier-activating enzyme 5（UBA5）,serves as the E1 to activate UFM1;UFM1-conjugating enzyme 1（UFC1） acts as the E2 to transfer the activated UFM1 to the active site of the E2;and the UFM1-specific ligase 1（UFL1） acts as the E3 to recognize its substrate,transfer,and ligate the UFM1 from E2 to the substrate.This process is called ufmylation.UFM1 chains can be cleaved from its target proteins by UFM1-specific proteases（Uf SPs）,suggesting that the ufmylation modification is reversible.UFM1 cascade is conserved among nearly all of the eukaryotic organisms,but not in yeast,and associated with several cellular activities including the endoplasmic reticulum stress response and hematopoiesis.Furthermore,the UFM1 cascade is closely related to a series of human diseases.In this review,we summarize the molecular details of this reversible modification process,the recent progress of its functional studies,as well as its implication in tumorigenesis and potential therapeutic targets for cancer.
基金supported by the Max Planck Societythe German Research Foundation DFG (SFB 635 to G.C., and SPP 1365 and grant BA1158/3–1 to A.B.)+1 种基金the Austrian Research Foundation FWF (grant P 21215 to A.B.)pre-doctoral fellowships from the International Max Planck Research School to R.B. and R.H
文摘Small ubiquitin-like modifier （SUMO） conjugation affects a broad range of processes in plants, including growth, flower initiation, pathogen defense, and responses to abiotic stress. Here, we investigate in vivo and in vitro a SUMO conjugating enzyme with a Cys to Ser change in the active site, and show that it has a dominant negative effect. In planta expression significantly perturbs normal development, leading to growth retardation, early flowering and gene expression changes. We suggest that the mutant protein can serve as a probe to investigate sumoylation, also in plants for which poor genetic infrastructure precludes analysis via loss-of-function mutants.
基金supported by grants from the State Key Development Program for Basic Research of the Ministry of Science and Technology of China(973 Program)(Grant Nos.2011CB910304 and 2012CB910204)to YLthe National Natural Science Foundation of China(Grant Nos.30925011,31030024 and 31021062).
文摘TANK-binding kinase 1(TBK1)is an important enzyme in the regulation of cellular antiviral effects.TBK1 regulates the activity of the interferon regulatory factors IRF3 and IRF7,thereby playing a key role in type I interferon(IFN)signaling pathways.The structure of TBK1 consists of an N-terminal kinase domain,a middle ubiquitin-like domain(ULD),and a C-terminal elongated helical domain.It has been reported that the ULD of TBK1 regulates kinase activity,playing an important role in signaling and mediating interactions with other molecules in the IFN pathway.In this study,we present the crystal structure of the ULD of human TBK1 and identify several con-served residues by multiple sequence alignment.We found that a hydrophobic patch in TBK1,containing residues Leu316,Ile353,and Val382,corresponding to the“Ile44 hydrophobic patch”observed in ubiquitin,was conserved in TBK1,IκB kinase epsilon(IKKε/IKKi),IκB kinase alpha(IKKα),and IκB kinase beta(IKKβ).In com-parison with the structure of the IKKβULD domain of Xenopus laevis,we speculate that the Ile44 hydrophobic patch of TBK1 is present in an intramolecular binding surface between ULD and the C-terminal elongated heli-ces.The varying surface charge distributions in the ULD domains of IKK and IKK-related kinases may be relevant to their specificity for specific partners.
基金Acknowledgments This study was funded by the National Natural Science Foundation of China （81570323, 30972709, 81061120527, 81241082） and the 12th Five-Year National Program of the Ministry of Scientific Technology （2012BAI10B01）. We thank Liu M and Zhou L from Beijing Hospital for providing experimental data, the nurses from Beijing Anzhen Hospital for collecting specimens, and the study volunteers.
文摘Background The genes encoding adiponectin receptor 1 （ADIPOR1） and small ubiquitin-like modifier 4 （SUM04） have been linked to anti-atherogenic effects, but little is known about whether polymorphisms in the two genes, acting separately or interacting, affect risk of coronary artery disease （CAD） without diabetes. Methods We genotyped 200 CAD patients without diabetes and 200 controls without CAD or diabetes at three single-nucleotide polymorphisms （SNPs） in ADIPOR1 and one SNP in SUM04, which were chosen based on previous studies. Potential associations were also explored between these SNPs and clinical characteristics of CAD without diabetes. Results Risk alleles at three SNPs inADIPOR1 （rs7539542-G, rs7514221-C and rs3737884-G） and the G allele at SNP rs237025 in SUM04 significantly increased risk of CAD without diabetes, with ORs ranging from 1.79 to 4.44. Carriers of any of these four risk alleles showed similar adverse clinical characteristics. Compared with individuals with a CC or GC genotype, those with a GG genotype at rs3737884 were at significantly higher risk of CAD that affected the left anterior descending coronary artery （OR： 6.77, P = 0.009）, the right coronary artery （OR： 4.81, P = 0.028） or a relatively large number of vessels （P = 0.04）. Individuals carrying a risk allele at one or more of the three SNPs in ADIPOR1 as well as a risk allele at the SNP in SUM04 were at significantly higher risk of CAD without diabetes than individuals not carrying any risk alleles （OR： 5.82, 95% CI： 1.23-27.7, P= 0.013）. Conelusions SNPs in ADIPORl and SUMO4 are associated with elevated risk of CAD without diabetes, and SNPs in the two genes may interact to jointly affect disease risk.
文摘BACKGROUND Colorectal cancer(CRC) is a common malignancy of the gastrointestinal tract. The worldwide mortality rate of CRC is about one half of its morbidity. Ubiquitin is a key regulatory factor in the cell cycle and widely exists in eukaryotes. Human leukocyte antigen F-associated transcript 10(FAT10), known as diubiquitin, is an 18 kDa protein with 29% and 36% homology with the N and C termini of ubiquitin. The function of FAT10 has not been fully elucidated, and some studies have shown that it plays an important role in various cell processes.AIM To examine FAT10 expression and to analyze the relationship between FAT10 expression and the clinicopathological parameters of CRC.METHODS FAT10 expression in 61 cases of CRC and para-cancer colorectal tissues was measured by immunohistochemistry and Western blotting. The relationship between FAT10 expression and clinicopathological parameters of CRC was statistically analyzed.RESULTS Immunohistochemical analysis showed that the positive rate of FAT10 expression in CRC(63.93%) was significantly higher than that in tumor-adjacent tissues(9.84%, P < 0.05) and normal colorectal mucosal tissue(1.64%, P < 0.05). Western blotting also indicated that FAT10 expression was significantly higher in CRC than in tumor-adjacent tissue(P < 0.05). FAT10 expression was closely associated with clinical stage and lymphatic spread of CRC. FAT10 expression also positively correlated with p53 expression.CONCLUSION FAT10 expression is highly upregulated in CRC. FAT10 expression is closely associated with clinical stage and lymphatic spread of CRC.
基金supported by Unggulan Research Grant from the Indonesian Institute of Sciences(LIPI)(Grant No.1139/F/2015)
文摘Small ubiquitin-like modifier(SUMO)-conjugating enzymes are involved in post-translational regulatory processes in eukaryotes, including the conjugation of SUMO peptides to protein substrate(SUMOylation). SUMOylation plays an important role in improving plant tolerance to abiotic stress such as salt, drought, heat and cold. Herein, we reported the isolation of OsSCE1(LOC_Os10 g39120) gene encoding a SUMO-conjugating enzyme from rice(Oryza sativa cv. Nipponbare) and its functional validation in response to drought stress. The E2 enzyme, Os SCE1, is one of three key enzymes involved in the conjugation of SUMO to its target proteins. Activated SUMO is transferred to the cysteine of an E2 enzyme and then to the target lysine residue of the substrate, with or without the help of an E3 SUMO ligase. Expression of OsSCE1 was strongly induced by polyethylene glycol 6000(PEG6000) treatment, which suggested OsSCE1 may be involved in the drought stress response. Overexpression of OsSCE1(OsSCE1-OX) in Nipponbare reduced the tolerance to drought stress. Conversely, the drought tolerance was slightly improved by the knockdown of OsSCE1(OsSCE1-KD). These results were further supported by measurement of proline content in OsSCE1-OX and OsSCE1-KD transgenic lines under induced drought stress, which showed OsSCE1-KD transgenic lines accumulated higher proline content than the wild type, whereas OsSCE1-OX line had lower proline content than the wild type. These findings suggested OsSCE1 may play a role as a negative regulator in response to drought stress in rice.
文摘In order to investigate the effect of small ubiquitin-like modifier-1 (SUMO-1) on the p53-induced HepG2 cell apoptosis, HepG2 cells were transfected by recombinant plasmids as pwtp53, pMDM2 and pSUMO-1 respectively. Western blot was employed to detect the protein expression of the transfected recombinant plasmids and the rate of apoptosis was measured by flow cytometry. The results showed that in cells transfected with pwtp53 and pwtp53+pSUMO-1, the apoptosis rate was (16.79±1.62) % and (18.15±1.36) % respectively, while transfected with pwtp53+pMDM2, the rate was decreased to (5.17±1.23) %. The apoptosis rate was (14.06±1.84) % in the cells transfected with pwtp53+pMDM2+pSUMO-1, significantly higher than that in the cells Transfected with pwtp53+pMDM2 (P<0.01). The apoptosis rates in the cells were all less than 2 % and had no significant difference among the groups. It was suggested that in the HepG2 cells, SUMO-1 can increase the apoptosis induced by wild-type p53 through binding to p53 protein, post-translational modification and inhibiting the p53 degradation by MDM2.
文摘目的:探讨UHRF1(Ubiquitin-like,containing PHD and RING finger domains 1)在肝细胞肝癌(hepatocellular carcinoma,HCC)中的表达及其与临床病理特征的关系。方法:采用免疫组织化学方法检测556例HCC组织及其癌旁组织中UHRF1的表达,分析其与HCC患者临床病理特征的关系。结果:免疫组织化学结果显示,UHRF1蛋白阳性表达定位于HCC细胞核,UHRF1蛋白在HCC组织中的表达显著高于癌旁组织。HCC组织中UHRF1蛋白阳性表达率为59%,其表达与肿瘤大小(P<0.01)、肿瘤分化(P<0.05)和微血管侵犯(P<0.01)相关。结论:HCC中UHRF1的表达与其恶性表型相关,UHRF1可能参与HCC的侵袭和转移。
文摘Different from canonical ubiquitin-like proteins, Hub1 does not form covalent conjugates with substrates but binds proteins noncovalently. In Socchoromyces cerevisioe, Hub1 associates with spUceosomes and mediates alternative splicing of SRCI, without affecting pre-mRNA splicing generaity. Human Hub1 is highty similar to its yeast homotog, but its cellular function remains largely unexplored. Here, we show that human Hub1 binds to the spliceosomal protein Snu66 as in yeast; however, unlike its 5. cerevisioe homolos, human Hub1 is essential for viability. Prolonged in vivo depletion of human Hub1 leads to various cellular defects, including splicing speckle abnormalities, partial nuclear retention of mRNAs, mitotic catastrophe, and consequently cell death by apoptosis. Early consequences of Hub1 depletion are severe splicing defects, however, only for specific splice sites leading to exon skipping and intron retention. Thus, the ubiquitin-iike protein Hub1 is not a canonlcal spliceosomal factor needed generally for splicing, but rather a modulator of spliceosome performance and facilitator of alternative splicing.
基金supported by the National High Technology Research and Development Program of China(863 Program,2011AA100204)the earmarked fund for the China Agriculture Research System(CARS-28)
文摘Radiation sensitivity proteins-23 （RAD23） are DNA repair factors participate in the ubiquitin/proteasome system （UPS）. Although the genome-wide analysis of RAD23 family members has been conducted in some species, little is known about RAD23 genes in apple （Malusxdomestica Borkh.）. We analyzed this gene family in M. domestica in terms of genomic locations, protein and promoter structures, and expressions in response to stresses. Various members showed a ubiqui- tous pattern of expression in all selected apple parts. Their expressions were altered under chilling, heat, and hydrogen peroxide treatments, as well as abscisic acid （ABA） treatment and water deficiency, suggesting their possible roles in plant stress responses. These results provide essential information about RAD23 genes in apple and will contribute to further functional studies.
基金the Science and Technology Department of Jilin Province(No.20150204006YY)
文摘AIM To investigate the function and mechanism of ubiquitinlike modifier activating enzyme 2(Uba2) in progression of gastric cancer(GC) cells.METHODS Uba2 level in patients with GC was analyzed by Western blotting and immunohistochemistry. MTT and colony formation assays were performed to examine cell proliferation.Flow cytometry was used for cell cycle analysis.Wound healing and Transwell assays were conducted to examine the effects of Uba2 on migration and invasion.Expression levels of cell cycle-related proteins, epithelial-mesenchymal transition(EMT) biomarkers, and involvement of the Wnt/β-catenin pathway was assessed by Western blotting. Activation of the Wnt/β-catenin pathway was confirmed by luciferase assay.RESULTS Uba2 expression was higher in GC than in normal tissues.Increased Uba2 expression was correlated with tissue differentiation, Lauren's classification, vascular invasion,and TNM stage, as determined by the analysis of 100 GC cases(P < 0.05). Knock-down of Uba2 inhibited GC cell proliferation, induced cell cycle arrest, and altered expression of cyclin D1, P21, P27, and Bcl-2, while upregulation of Uba2 showed the opposite effects. The wound healing and Transwell assays showed that Uba2 promoted GC cell migration and invasion. Western blotting revealed alterations in EMT biomarkers, suggesting the role of Uba2 in EMT. Furthermore, the luciferase reporter assay indicated the involvement of the Wnt/β-catenin signaling pathway as a possible modulator of Uba2 oncogenic functions.CONCLUSION Uba2 plays a vital role in GC cell migration and invasion,possibly by regulating the Wnt/β-catenin signaling pathway and EMT.
基金supported by grants from the National Key Basic Research Program of China (2004CB518807, 2007CB512403)the National Natural Science Foundation of China (30772004, 30121002, 30600539)the Natural Science Foundation of Shanghai (06QA14069).
文摘We identified a novel ubiquitin-like molecule DULP from human dendritic cells. DULP contains a domain that shares 26% identity and 34% similarity with ubiquitin, and it possesses the corresponding Ile-44 hydrophobic patch used by mono- or poly-ubiquitin to interact with a ubiquitin-interaction motif （UIM） or ubiquitin-associated domain （UBA）. Lysine residue corresponding to 6 of ubiquitin, which is involved in the formation of a multi-ubiquitin chain that can bind proteasomal subunit Rpn10/S5a, is also conserved in its ubiquitin-homology domain. However, DULP does not possess the highly conserved C-terminus Gly-Gly required for ubiquitin conjugation or the Lys-48 required for the formation of polyubiquitin chain to target substrates for degradation, suggesting it might be a novel ubiquitin-domain protein （UDP）. DULP was found widely expressed in many cells and the ubiquitin-homology domain was not cleaved. We also confirmed that DULP expression was enriched in the nucleus and much weaker in the cytosol. Besides, we found that overexpression of DULP in 293T cells induced apoptosis, which might not be associated with the mitochondrial or proteasome pathway, with the specific mechanism remain unclear. Further investigations are needed to identify the precise biological functions of DULP. Cellular ＆ Molecular Immunology.
基金This study was supported by the National Key R&D Program of China(nos.2017YFA0505200 and 2017YFA0505400)the National Natural Science Foundation of China(nos.91753205,21877024,21977089,81621002,and 21621003)the Fundamental Research Funds for the Central Universities(no.JZ2019HGPB0105).
文摘Small ubiquitin-like modifiers(SUMOs)are protein modifiers that can form polymeric chains.They are important signals in cellular processes,and their study and profiling require the development of molecular tools.Herein,the authors have reported an efficient chemical protein synthesis approach for the generation of dimeric SUMO-2-based photoaffinity probes through the ligation of four readily synthesizable peptides.Proteomic studies using this diSUMO-2 probe on HeLa cell nuclear lysate found it to capture a significantly different selection of proteins compared with its monoSUMO counterparts.This resulted in the identification of several previously unknown SUMO chain-specific interacting proteins such as 40S ribosomal protein S3,which showed a significantly higher affinity for polySUMO chains than monomeric SUMO.Collectively,these results emphasize the need to develop SUMO chain-based probes in other species,and to shed light on the important role of polySUMOylation in diseases.
基金supported by NIH CORE Grant P30 EY08098 to the Department of Ophthalmology,University of Pittsburgh,the Eye and Ear Foundation of Pittsburgh (to KCC)。
文摘SRY-related HMG-box(Sox) transcription factors are known to regulate central nervous system development and are involved in several neurological diseases.Post-translational modification of Sox proteins is known to alter their functions in the central nervous system.Among the different types of post-translational modification,small ubiquitin-like modifier(SUMO) modification of Sox proteins has been shown to modify their transcriptional activity.Here,we review the mechanisms of three Sox proteins in neuronal development and disease,along with their transcriptional changes under SUMOylation.Across three species,lysine is the conserved residue for SUMOylation.In Drosophila,SUMOylation of Sox N plays a repressive role in transcriptional activity,which impairs central nervous system development.However,de SUMOylation of Sox E and Sox11 plays neuroprotective roles,which promote neural crest precursor formation in Xenopus and retinal ganglion cell differentiation as well as axon regeneration in the rodent.We further discuss a potential translational therapy by SUMO site modification using AAV gene transduction and Clustered regularly interspaced short palindromic repeats-Cas9 technology.Understanding the underlying mechanisms of Sox SUMOylation,especially in the rodent system,may provide a therapeutic strategy to address issues associated with neuronal development and neurodegeneration.
