Transcription factor Oct4 plays critical roles in maintaining pluripotency and controlling lineage commitment of embryonic stem cells （ESCs）. Our previous study indicates that Wwp2, a mouse HECT-type E3 ubiquitin li...Transcription factor Oct4 plays critical roles in maintaining pluripotency and controlling lineage commitment of embryonic stem cells （ESCs）. Our previous study indicates that Wwp2, a mouse HECT-type E3 ubiquitin ligase, ubiquitinates Oct4 and promotes its degradation in a heterologous system. However, roles of Wwp2 in regulating en- dogenous Oct4 protein levels as well as molecular characteristics of the function of Wwp2 have not been determined. Here, we report that Wwp2 plays an important role in Oct4 ubiquitination and degradation during differentiation of embryonal carcinoma cells （ECCs）, although it does not appear to affect Oct4 protein levels in the undifferentiated ECCs and ESCs. Importantly, inhibition of Wwp2 expression by specific RNA interference elevates the Oct4 protein level, leading to attenuation in retinoid acid-induced activation of differentiation-related marker genes. Mechanisti- cally, Wwp2 catalyzes Oct4 poly-ubiquitination via the lysine 63 linkage in a dosage-dependent manner. Interest- ingly, Wwp2 also regulates its own ligase activity in a similar manner. Moreover, auto-ubiquitination of Wwp2 occurs through an intra-molecular mechanism. Taken together, these results demonstrate a crucial role of Wwp2 in con- trolling endogenous Oct4 protein levels during differentiation processes of ECCs and suggest an interesting dosage- dependent mechanism for regulating the catalytic activity of the E3 ubiquitin ligase, Wwp2.展开更多
Despite complications were significantly reduced due to the popularity of percutaneous coronary intervention(PCI) in clinical trials, reperfusion injury and chronic cardiac remodeling significantly contribute to poor ...Despite complications were significantly reduced due to the popularity of percutaneous coronary intervention(PCI) in clinical trials, reperfusion injury and chronic cardiac remodeling significantly contribute to poor prognosis and rehabilitation in AMI patients. We revealed the effects of HSP47 on myocardial ischemia-reperfusion injury(IRI) and shed light on the underlying molecular mechanism.We generated adult mice with lentivirus-mediated or miRNA(mi1/133TS)-aided cardiac fibroblastselective HSP47 overexpression. Myocardial IRI was induced by 45-min occlusion of the left anterior descending(LAD) artery followed by 24 h reperfusion in mice, while ischemia-mediated cardiac remodeling was induced by four weeks of reperfusion. Also, the role of HSP47 in fibrogenesis was evaluated in cardiac fibroblasts following hypoxia-reoxygenation(HR). Extensive HSP47 was observed in murine infarcted hearts, human ischemic hearts, and cardiac fibroblasts and accelerated oxidative stress and apoptosis after myocardial IRI. Cardiac fibroblast-selective HSP47 overexpression exacerbated cardiac dysfunction caused by chronic myocardial IRI and presented deteriorative fibrosis and cell proliferation.HSP47 upregulation in cardiac fibroblasts promoted TGFβ1-Smad4 pathway activation and Smad4 deubiquitination by recruiting ubiquitin-specific peptidase 10(USP10) in fibroblasts. However, cardiac fibroblast specific USP10 deficiency abolished HSP47-mediated fibrogenesis in hearts. Moreover, blockage of HSP47 with Col003 disturbed fibrogenesis in fibroblasts following HR. Altogether, cardiac fibroblast HSP47 aggravates fibrosis post-myocardial IRI by enhancing USP10-dependent Smad4 deubiquitination,which provided a potential strategy for myocardial IRI and cardiac remodeling.展开更多
[Objective] This study aimed to clone ubiquitin-conjugating enzyme gene TaUBC4 from different wheat cultivars and thus analyze their phylogenetic relationship.[Method] The UBC4 coding sequences were cloned through rev...[Objective] This study aimed to clone ubiquitin-conjugating enzyme gene TaUBC4 from different wheat cultivars and thus analyze their phylogenetic relationship.[Method] The UBC4 coding sequences were cloned through reverse transcription PCR （RT-PCR） from 21 wheat varieties.After sequencing,the UBC4 sequence in wheat cultivar Zhongguochun （GenBank accession No：M28059） was selected as the reference gene,to analyze the mutation frequency and evolutionary distance in the CDSs and corresponding amino acid sequences of the different wheat cultivars.Moreover,the phylogenetic tree based on the amino acid sequences of these TaUBC4 genes were constructed,involving the homologous sequences of TaUBC4 in eight other monocots.[Result] TaUBC4 sequence was highly conserved because the similarity in DNA sequences of the wheat varieties was over 94％,while that in amino acid sequence was over 96％.And the amino acid sequence difference only can be seen at two sites among some varieties.Phylogenetic tree constructed revealed the evolutionary relationships among these wheat varieties.[Conclusion] This study reveals the polymorphism and evolutionary characteristics in the nucleotide and amino acid sequences in different wheat varieties,which lays foundation for investigating the evolution and biological function of TaUBC4 gene.In addition,the phylogenetic tree constructed provides theoretical references for the classification of the wheat varieties with complicated background.展开更多
Objective Ubiquitin-specific protease 4(USP4)facilitates the development of transforming growth factor-beta 1(TGF-β1)-induced epithelial-mesenchymal transition(EMT)in various cancer cells.Moreover,EMT of renal tubula...Objective Ubiquitin-specific protease 4(USP4)facilitates the development of transforming growth factor-beta 1(TGF-β1)-induced epithelial-mesenchymal transition(EMT)in various cancer cells.Moreover,EMT of renal tubular epithelial cells(RTECs)is required for the progression of renal interstitial fibrosis.However,the role of USP4 in EMT of RTECs remains unknown.The present study aimed to explore the effect of USP4 on the EMT of RTECs as well as the involved mechanism.Methods In established unilateral ureteral obstruction(UUO)rats and NRK-52E cells,immunohistochemistry and Western blot assays were performed.Results USP4 expression was increased significantly with obstruction time.In NRK-52E cells stimulated by TGF-β1,USP4 expression was increased in a time-dependent manner.In addition,USP4 silencing with specific siRNA indicated that USP4 protein was suppressed effectively.Meanwhile,USP4 siRNA treatment restored E-cadherin and weakened alpha smooth muscle actin(α-SMA)expression,indicating that USP4 may promote EMT.After treatment with USP4 siRNA and TGF-β1 for 24 h,the expression of TGF-β1 receptor type I(TβRI)was decreased.Conclusion USP4 promotes the EMT of RTECs through upregulating TβRI,thereby facilitating renal interstitial fibrosis.These findings may provide a potential target of USP4 in the treatment of renal fibrosis.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
基金We thank Dr Richard Baer （Pathology, Columbia University, New York, USA） for generously providing various Ub mutant plasmids. This study was supported by Grants from the National Natural Science Foundation of China （30871257, 30730051） and the National High Technology Research, Development Program of China （2006CB943901 and 2007CB947904）, the Shanghai Sci- ence and Technology Developmental Foundation （08JC1413100） and the Shanghai Leading Academic Discipline Project （$30201）.
文摘Transcription factor Oct4 plays critical roles in maintaining pluripotency and controlling lineage commitment of embryonic stem cells （ESCs）. Our previous study indicates that Wwp2, a mouse HECT-type E3 ubiquitin ligase, ubiquitinates Oct4 and promotes its degradation in a heterologous system. However, roles of Wwp2 in regulating en- dogenous Oct4 protein levels as well as molecular characteristics of the function of Wwp2 have not been determined. Here, we report that Wwp2 plays an important role in Oct4 ubiquitination and degradation during differentiation of embryonal carcinoma cells （ECCs）, although it does not appear to affect Oct4 protein levels in the undifferentiated ECCs and ESCs. Importantly, inhibition of Wwp2 expression by specific RNA interference elevates the Oct4 protein level, leading to attenuation in retinoid acid-induced activation of differentiation-related marker genes. Mechanisti- cally, Wwp2 catalyzes Oct4 poly-ubiquitination via the lysine 63 linkage in a dosage-dependent manner. Interest- ingly, Wwp2 also regulates its own ligase activity in a similar manner. Moreover, auto-ubiquitination of Wwp2 occurs through an intra-molecular mechanism. Taken together, these results demonstrate a crucial role of Wwp2 in con- trolling endogenous Oct4 protein levels during differentiation processes of ECCs and suggest an interesting dosage- dependent mechanism for regulating the catalytic activity of the E3 ubiquitin ligase, Wwp2.
基金supported by grants from the National Key R&D Program of China (2018YFC1311300)the Key Project of the National Natural Science Foundation of China (No. 81530012)+3 种基金the National Natural Science Foundation of China (Nos. 81860080, 82170245 and 81700254)the Fundamental Research Funds for the Central Universities (2042018kf1032, China)the Development Center for Medical Science and Technology National Health and Family Planning Commission of the People’s Republic of China (The prevention and control project of cardiovascular disease, 2016ZX008-01)Science and Technology Planning Projects of Wuhan (2018061005132295)
文摘Despite complications were significantly reduced due to the popularity of percutaneous coronary intervention(PCI) in clinical trials, reperfusion injury and chronic cardiac remodeling significantly contribute to poor prognosis and rehabilitation in AMI patients. We revealed the effects of HSP47 on myocardial ischemia-reperfusion injury(IRI) and shed light on the underlying molecular mechanism.We generated adult mice with lentivirus-mediated or miRNA(mi1/133TS)-aided cardiac fibroblastselective HSP47 overexpression. Myocardial IRI was induced by 45-min occlusion of the left anterior descending(LAD) artery followed by 24 h reperfusion in mice, while ischemia-mediated cardiac remodeling was induced by four weeks of reperfusion. Also, the role of HSP47 in fibrogenesis was evaluated in cardiac fibroblasts following hypoxia-reoxygenation(HR). Extensive HSP47 was observed in murine infarcted hearts, human ischemic hearts, and cardiac fibroblasts and accelerated oxidative stress and apoptosis after myocardial IRI. Cardiac fibroblast-selective HSP47 overexpression exacerbated cardiac dysfunction caused by chronic myocardial IRI and presented deteriorative fibrosis and cell proliferation.HSP47 upregulation in cardiac fibroblasts promoted TGFβ1-Smad4 pathway activation and Smad4 deubiquitination by recruiting ubiquitin-specific peptidase 10(USP10) in fibroblasts. However, cardiac fibroblast specific USP10 deficiency abolished HSP47-mediated fibrogenesis in hearts. Moreover, blockage of HSP47 with Col003 disturbed fibrogenesis in fibroblasts following HR. Altogether, cardiac fibroblast HSP47 aggravates fibrosis post-myocardial IRI by enhancing USP10-dependent Smad4 deubiquitination,which provided a potential strategy for myocardial IRI and cardiac remodeling.
基金Supported by the Natural Science Foundation of Shandong Province(ZR2011CQ035)Scientific and Technological Innovation Fund for the Undergraduates of Liaocheng University(F2013274)~~
文摘[Objective] This study aimed to clone ubiquitin-conjugating enzyme gene TaUBC4 from different wheat cultivars and thus analyze their phylogenetic relationship.[Method] The UBC4 coding sequences were cloned through reverse transcription PCR （RT-PCR） from 21 wheat varieties.After sequencing,the UBC4 sequence in wheat cultivar Zhongguochun （GenBank accession No：M28059） was selected as the reference gene,to analyze the mutation frequency and evolutionary distance in the CDSs and corresponding amino acid sequences of the different wheat cultivars.Moreover,the phylogenetic tree based on the amino acid sequences of these TaUBC4 genes were constructed,involving the homologous sequences of TaUBC4 in eight other monocots.[Result] TaUBC4 sequence was highly conserved because the similarity in DNA sequences of the wheat varieties was over 94％,while that in amino acid sequence was over 96％.And the amino acid sequence difference only can be seen at two sites among some varieties.Phylogenetic tree constructed revealed the evolutionary relationships among these wheat varieties.[Conclusion] This study reveals the polymorphism and evolutionary characteristics in the nucleotide and amino acid sequences in different wheat varieties,which lays foundation for investigating the evolution and biological function of TaUBC4 gene.In addition,the phylogenetic tree constructed provides theoretical references for the classification of the wheat varieties with complicated background.
文摘Objective Ubiquitin-specific protease 4(USP4)facilitates the development of transforming growth factor-beta 1(TGF-β1)-induced epithelial-mesenchymal transition(EMT)in various cancer cells.Moreover,EMT of renal tubular epithelial cells(RTECs)is required for the progression of renal interstitial fibrosis.However,the role of USP4 in EMT of RTECs remains unknown.The present study aimed to explore the effect of USP4 on the EMT of RTECs as well as the involved mechanism.Methods In established unilateral ureteral obstruction(UUO)rats and NRK-52E cells,immunohistochemistry and Western blot assays were performed.Results USP4 expression was increased significantly with obstruction time.In NRK-52E cells stimulated by TGF-β1,USP4 expression was increased in a time-dependent manner.In addition,USP4 silencing with specific siRNA indicated that USP4 protein was suppressed effectively.Meanwhile,USP4 siRNA treatment restored E-cadherin and weakened alpha smooth muscle actin(α-SMA)expression,indicating that USP4 may promote EMT.After treatment with USP4 siRNA and TGF-β1 for 24 h,the expression of TGF-β1 receptor type I(TβRI)was decreased.Conclusion USP4 promotes the EMT of RTECs through upregulating TβRI,thereby facilitating renal interstitial fibrosis.These findings may provide a potential target of USP4 in the treatment of renal fibrosis.
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.
