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.

Effect of small ubiquitin-like modifier 1 pseudogene 3 on the proliferation and apoptosis of non-small cell lung cancer cell line H1299 through protein kinase B signaling pathway / 解剖学报

Objective To investigate the effect of long noncoding RNA (IncRNA) small ubiquitin-like modifier 1 pseudogene 3(SUM01P3) on the proliferation and apoptosis of non-small cell lung cancer cell line 1299. Methods Determination of SUM01P3 expression in non-small cell lung cancer cells by Real-time PCR. SUM01P3 small interfering RNA(siRNA) was transfected into H1299 cells, the down regulation effect was determined by Real-time PCR. Cell proliferation was measured by MTT, 5-ethynyl-2′-deoxyuridine(EdU) method, the cell cycle was determined by PI single staining, apoptosis was detected by annexin V -FITC/PI, detection of apoptosis by TUNEL, Western blotting was used to detect the expression of cleaved Caspase-3 (c-Caspase-3), cyclin Dl, P27, phosphorylated phospoinositide 3-kinase (p-PI3K) and phosphorylated protein kinase B (p-Akt). Akt signal activator treated H1299 cells transfected with SUM01P3 siRNA, cell proliferation, apoptosis and cycle change were also measured by the above methods. The number of samples was 9. Results SUM01P3 was up-regulated in non-small cell lung cancer cells. The expression of SUM01P3 in H1299 cells decreased after transfection with SUM01P3 siRNA, cell proliferation decreased, the ratio of G0/Gj phase increased, apoptosis rate increased, c-Caspase-3 and P27 protein in the cells increased, the protein levels of cyclin D1, p-PI3K and p-Akt decreased. Akt signal activator could reverse the inhibition of proliferation, cycle arrest and apoptosis of H1299 cells by SUM01P3 siRNA. Conclusion Down-regulation of SUM01P3 inhibits the proliferation of non-small cell lung cancer H1299 cells and induces apoptosis, the mechanism of action is related to the reduction of the activation level of the Akt signaling pathway.

Small ubiquitin-like modifier proteins specific protease 3 in microglia participating in the early progression of photothrombosic ischemic stroke mice model / 解剖学报

Objective To investigate the expression of small ubiquitin-like modifier proteins specific protease 3 (SENP3) in microglia of mice with ischemic stroke and its relationship with the progression of ischemic stroke. Methods The experimental animals were divided into control group, ischemic stroke day 1 group and ischemic stroke day 7 group (3 mice per group). The expression of inducible nitric oxide synthase (iNOS), argniase-1 (ARG-1), SENP3 and c-Jun N-terminal kinase (JNK) phosphorylation levels in the striatum were detected by immunoblotting. The expression of iNOS and ARG-1 in mouse striatum microglia was detected by immunofluorescence double labeling. Results Compared with the control group, the expression of SENP3 and the phosphorylation level of JNK in the ischemic stroke group increased significantly, and the expression of the marker iNOS of Ml type microglia increased significantly. The expression of the marker ARG-1 of M2 type microglia increased significantly in the day 7 group of ischemic stroke. The immunofluorescence double-labeled result of striatum ionized calcium binding adapter molecule 1 (Ibal) and iNOS, Ibal and ARG-1 were consistent with the result of immunoblotting. Conclusion In the early stage of ischemic stroke, the expression of SENP3 in microglia increases, which promote the cerebral inflammatory response by affecting the level of JNK phosphorylation and the polarization of microglia, and participate in the progression of ischemic stroke.

Effect of selective brain hypothermia on SUMOylation of cerebral cortex during cerebral ischemia-reperfusion in rats / 中华麻醉学杂志

Objective To evaluate the effect of selective brain hypothermia on small ubiquitin-like modifier (SUMO)ylation of cerebral cortex during cerebral ischemia-reperfusion (I/R) in rats.Methods A total of 120 healthy clean-grade male Sprague-Dawley rats,aged 8 weeks,weighing 200-250 g,were divided into 4 groups (n=30 each) by a random number table method:sham operation group (group S),group I/R,selective brain hypothermia group (group H) and 37 ℃ normal saline group (group N).Rats were anesthetized with 10％ chloral hydrate 3 ml/kg.Cerebral ischemia was induced by middle cerebral artery occlusion using a nylon thread with rounded tip inserted into the right internal carotid artery and advanced cranially until resistance was met.The right middle cerebral artery was occluded for 2 h followed by reperfusion in group I/R.10-13 ℃ normal saline was infused at the rate of 100 ml · kg-1 · h-1 for 20 min starting from the time point immediately after removing the nylon thread in group H.37 ℃ normal saline was infused instead at the same rate for 20 min in N group.The neurological deficit were assessed and scored at 6,24 and 48 h after reperfusion.The cerebral cortex on ischemic side was then removed for determination of cell apoptosis (by TUNEL) and expression of SUMO sepcific proteases 3 (SENP3) and SUMO2/3-conjugated protein (by Western blot).The apoptotic rate was calculated.Results Compared with group S,the neurological deficit score and apoptosis rate were significantly increased,and the expression of SUMO2/3-conjugated protein was up-regulated at each time point after reperfusion in the other three groups (P＜0.05),and the expression of SENP3 was significantly up-regulated in I/R and N groups and down-regulated in group H (P＜0.01).Compared with group I/R,the neurological deficit score and apoptosis rate were significantly decreased,the expression of SUMO2/3-conjugated protein was up-regulated,and the expression of SENP3 was down-regulated in group H (P＜0.05).Conclusion The mechanism by which selective brain hypothermia reduces cerebral I/R injury is related to enhancing SUMOylation of cerebral cortex in rats.

Construction of fusion expression vector pET22b-SUMO-FGFR4 and optimization of expression conditions in E.coli / 吉林大学学报(医学版)

Objective:To design the small ubiquitin modification-fibroblast growth factor receptor 4 (SUMO-FGFR4) fusion gene and construct the expression vector pET22b-SUMO-FGFR4, to optimize the expression conditions. Methods:The SUMO-FGFR4 fusion gene was obtained by Overlap PCR and was connected to pET22b;the recombinant expression vector pET22b-SUMO-FGFR4 was obtained. The influence of lactose concentration, induction time,induction temperature,induction point and adding mode of lactose in the expression levels was observed,and the best induction condition was determined; then the solubility of recombinant protein was analyzed.Results:The SUMO-FGFR4 fusion protein was highly expressed,the molecular weight of the fusion protein was about 40 000 and it could bind with FGFR4 specific antibody.When the lactose concentration was 1.0 g·L-1 ,the induction time was 3 h,the induction temperature was 37℃,the value of A (600)was 0.8,the expression level was highest;but adding mode of lactose had no remarkable effect on the protein expression.The expression level of recombinant protein induced by lactose was higher than IPTG.SUMO-FGFR4 protein existed in a form of inclusion body.Conclusion:The SUMO-FGFR4 fusion protein is expressed successfully in this study while lactose is used as inducer and the best expression conditions are confirmed.

Correlation between RSUME sumoylation and HIF-1α/VEGF pathway in gliomas / 西安交通大学学报(医学版)

Objective To explore the expressions and correlation of RWD containing sumoylation enhancer (RSUME),small ubiquitin-like modifier (SUMO-1),hypoxia inducible factor-1α(HIF-1α)and vascular endothelial growth factor (VEGF)in gliomas of different pathologic grade.Methods We investigated the expression levels of RSUME mRNA,HIF-1α mRNA and VEGF mRNA with reverse transcription-polymerase chain reaction (RT-PCR),and investigated the immunohistochemical staining to determine the expressions of SUMO-1,HIF-1α and VEGF in 63 cases of human gliomas of different pathologic grade and 9 cases of normal brain tissues.We studied its correlation with the pathologic grade and the relationship between the expression of RSUME promoter sumoylation and HIF-1α/VEGF pathway in gliomas.Results There were significant differences (P <0.01)in the expressions of RSUME mRNA,HIF-1αmRNA and VEGF mRNA in glioma tissues.With the increasing degree of pathologic grade in tumor specimens,the expression levels of RSUME mRNA,HIF-1α mRNA and VEGF mRNA increased markedly (P <0.01 ).There was a positive correlation of the expression levels of RSUME mRNA with HIF-1αmRNA and VEGF mRNA.There were significant differences (P <0.01 )in the expressions of SUMO-1,HIF-1αand VEGF in glioma tissues by immunohistochemical staining.With the ascending of pathologic grade of tumor specimens,the expression levels of SUMO-1,HIF-1α and VEGF increased markedly (P < 0.01 ).There was a positive correlation between the expression level of SUMO-1 and HIF-1α(r =0.857,P <0.01).The Kaplan-Meier analysis and Log-rank test showed significant differences in progress free survival (PFS)between the RSUME high-expression and low-expression groups (χ2 =36.032,P <0.01).Conclusion RSUME may enhance HIF-1α/VEGF pathway through sumoylation in gliomas.It implicates that RSUME is related to angiogenesis in gliomas and can promote tumor invasion and progression,indicating that RSUME can be a novel target in gliomas treatment.

Small ubiquitin-like modifier 4 M55V polymorphism is not associated with diabetic nephropathy in Iranian type 2 diabetes patients.

INTRODUCTION: We studied the impact of small ubiquitin-like modifier 4 (SUMO4) M55V polymorphism on susceptibility to diabetic nephropathy in Iranian type 2 diabetes patients. MATERIALS AND METHODS: The patient group consisted of 50 Iranian type 2 diabetes patients with nephropathy, and the control group consisted of 50 Iranian type 2 diabetes patients without nephropathy. Genotyping was performed using polymerase chain reaction-restriction fragment length polymorphism method for the M55V. RESULTS: The frequency of SUMO4 AA, AG, and GG genotypes were 23%, 18%, and 9% in the patient group and 10%, 22%, and 18% in the control group. There was no significant difference in frequency of SUMO4 genotypes in patients compared to controls. CONCLUSION: These findings indicate that SUMO4 M55V polymorphism is not associated with diabetic nephropathy in Iranian type 2 diabetes patients.

SUMO-1 Enhancing the p53-induced HepG2 Cell Apoptosis / 华中科技大学学报（医学）（英德文版）

Summary: 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.

SUMO-1 Enhances Apoptosis Induced by Wild-Type p53 Plasmid Transfection in HepG2 Cells / 中国普外基础与临床杂志

Objective To investigate whether SUMO-1 enhances the apoptosis induced by wild-type p53 plasmid transfection in HepG2 cells. Methods The HepG2 cells were transfected respectively or simultaneouly with the following expressional plasmids as pcDNA3-wtp53(pwtp53,including human wild-type p53 gene),pCMV-HDM1B(pMDM2,including HDM2 gene, homologous gene as murine double minute gene 2),pcDNA3-His6-SUMO-1(pSUMO-1 ,including small ubiquitin-like modifier-1 gene)and plasmid pcDNA3.The proteins expressed in cells were detected by means of Western blotting and the apoptosis rates of cells were measured by flow cytometry. Results The protein bands of p53 and MDM2 could be seen in cells transfected with pwtp53 and pMDM2. Meanwhile,the relative larger molecular weight bands were also seen in cells transfected with pSUMO-1 which represented the p53 and MDM2 protein modification by SUMO-1. Merely the trace of p53 protein was detected in cells not transfected with any plasmid or only transfected with empty plasmid and pSUMO-1. In cells transfected with pwtp53 and pwtp53+pSUMO-1,the apoptosis rates were (16.79?1.62)% and (18.15?1.36)%. When transfected with pwtp53+pMDM2,the rate decreased to (5.17?1.23)%. The apoptosis rate would come up again to (14.06?1.84)% after transfected with pwtp53+pMDM2+pSUMO-1 and the difference of rates were significant compared to the cells transfected with pwtp53+pMDM2 (P

Small ubiquitin-like modifier and cancer / 医学研究生学报

Small ubiquitin-like modifiers(SUMO) are ubiquitin-related proteins that can be covalently conjugated to cellular target proteins.Frequently,this modification has a key role in regulating the activities of those targets and,hence,their cellular functions.Researches show that some oncoproteins,tumor suppressors,DNA repair proteins and cyclins are target proteins of SUMO modification and the altered expression of some enzymes related to SUMO conjugation occurs in some neoplasm.It is indicated that sumoylation is important in tumor origination,development and metastasis.