Case Report: RNF213 variant and choroidal anastomosis as potential risk factors for early stroke in moyamoya syndrome associated with Down syndrome.

Introduction: Recent studies have suggested associations between RNF213 variants and the formation of periventricular anastomosis among patients with moyamoya disease, leading to early onset of cerebral hemorrhage and rebleeding. Case description: We report herein the case of a boy with Down syndrome and moyamoya syndrome. Exome sequencing identified a heterozygous RNF213 R4810K variant. After ischemic stroke occurred at 9 years old, indirect surgical revascularization was performed for the left cerebral hemisphere and improved ischemic symptoms and cerebral hypoperfusion, while the left choroidal anastomosis remained. At 13 years old, he presented with left thalamic hemorrhage attributed to the anterior choroidal artery, with rebleeding observed four days after the initial hemorrhage under strict blood pressure control. The patient was discharged without neurological deficits 20 days after the hemorrhagic stroke. Conclusion: Presence of an RNF213 variant and choroidal anastomosis may represent risk factors for cerebral hemorrhage in patients with Down syndrome and moyamoya syndrome, as well as in patients with moyamoya disease.

Ubiquitin signaling in pancreatic ductal adenocarcinoma.

Pancreatic ductal adenocarcinoma (PDAC) is a highly lethal malignant tumor of the digestive system, characterized by rapid progression and being prone to metastasis. Few effective treatment options are available for PDAC, and its 5-year survival rate is less than 9%. Many cell biological and signaling events are involved in the development of PDAC, among which protein post-translational modifications (PTMs), such as ubiquitination, play crucial roles. Catalyzed mostly by a three-enzyme cascade, ubiquitination induces changes in protein activity mainly by altering their stability in PDAC. Due to their role in substrate recognition, E3 ubiquitin ligases (E3s) dictate the outcome of the modification. Ubiquitination can be reversed by deubiquitylases (DUBs), which, in return, modified proteins to their native form. Dysregulation of E3s or DUBs that disrupt protein homeostasis is involved in PDAC. Moreover, the ubiquitination system has been exploited to develop therapeutic strategies, such as proteolysis-targeting chimeras (PROTACs). In this review, we summarize recent progress in our understanding of the role of ubiquitination in the development of PDAC and offer perspectives in the design of new therapies against this highly challenging disease.

Identification and study of regulatory axis that miRNA-224-5p targets NEDD4L gene in clear cell renal cell carcinoma / 肿瘤研究与临床

Objective:To screen key genes of renal clear cell carcinoma based on bioinformatics methods, identify possible microRNA (miRNA)-mRNA action axis, and explore the expression of related genes in clear cell renal cell carcinoma tissues and cells.Methods:Gene expression profiles of GSE40435 and GSE71302 datasets were obtained from the Gene Expression Omnibus (GEO) database. TCGA-KIRC datasets were obtained from The Cancer Genome Atlas (TCGA) database. R software was used to identify the differentially expressed mRNA and miRNA, and the functional enrichment analysis was performed. STRING database and Cytoscape software were used to perform the protein interaction analysis. The prognosis-related differentially expressed miRNA was evaluated by the Oncomir database. The potential targeted genes regulated by miRNA were determined by using TargetScan and miRDB targeted gene prediction tools. The tissue samples and clinicopathological features of 34 patients with clear cell renal cell carcinoma in the First Hospital of Shanxi Medical University from June to December 2021 were collected, and normal renal cell line 293T and clear cell renal cell carcinoma cell line 786O were selected. The real-time fluorescence quantitative polymerase chain reaction (qRT-PCR), was used to detect the relative expression of genes; Western blotting and immunohistochemical staining were used to detect the expression levels of the targeted proteins. The dual luciferase reporter gene assay was carried out to verify the targeting relationship between genes.Results:A total of 1 351 differentially expressed mRNA and 50 differentially expressed miRNA were screened and identified. The result of functional enrichment analysis suggested that the fatty acid metabolism pathway and xenobiotic metabolism pathway were suppressed in clear cell renal cell carcinoma, while the apoptosis and immune response pathways were activated. Protein interaction analysis suggested that the signal transduction and protein ubiquitination pathways might play a key role in clear cell renal cell carcinoma. The screening results showed that miRNA-224-5p (miR-224-5p) was most closely associated with clear cell renal cell carcinoma progression and was highly expressed in tumor tissues, and its prognosis-related target gene was NEDD4L. The relative expression of NEDD4L mRNA in clear cell renal cell carcinoma tissues and paraneoplastic tissues were 0.138±0.103 and 1.000±0.026 ( t = 46.23, P < 0.05), and the relative expression of miR-224-5p was 1.000±0.043 and 0.129±0.108 ( t = 45.28, P < 0.05). The differences of NEDD4L mRNA and miR-224-5p expressions in different grades and stages of clear cell renal cell carcinoma tissues were statistically significant (all P < 0.05). The expression of NEDD4L protein was decreased in clear cell renal cell carcinoma. The relative expression of NEDD4L gene in 293T and 786O cells were 1.000±0.125 and 0.210±0.044 ( t = 17.52, P < 0.05); the relative expressions of miR-224-5p gene were 0.209±0.049 and 1.000±0.234 ( t = 10.61, P < 0.05). The relative expressions of NEDD4L mRNA in miRNA mimic group and negative control group were 0.236±0.062 and 1.000±0.024, and the difference was statistically significant ( t = 43.56, P < 0.05). NEDD4L protein expression was reduced in the miRNA mimic group. Dual luciferase reporter gene assay suggested that NEDD4L was a direct target gene of miR-224-5p. Conclusions:In clear cell renal cell carcinoma, miR-224-5p targets and regulates NEDD4L expression, and this mechanism may be related to carcinogenesis and progression of clear cell renal cell carcinoma.

Correlation between Ubiquitin E3 Ligases (SIAHs) and Heat Shock Protein 90 in Breast Cancer Patients.

Background: Breast cancer is a heterogeneous disease and differences in the expression levels of the ER, PR, and HER2 the triplet of established biomarkers used for clinical decision-making have been reported among breast cancer patients. Furthermore, resistance to anti-estrogen and anti-HER2 therapies emerges in a considerable rate of breast cancer patients, and novel drug therapies are required. Several anomalous signaling pathways have been known in breast cancer have been known; heat shock protein 90 (HSP90) is one of the most plenty proteins in breast cells. The family of ubiquitin ligases such as SIAH1 and SIAH2 is known to specifically target misfolded proteins to the proteasome; also, they have been illustrated to play a role in RAS signaling and as an essential downstream signaling component required for EGFR/HER2 in breast cancer. Methods: The expression of SIAH2, HSP90, and HER2 was assessed by quantitative Real-Time PCR in 85 invasive ductal carcinoma breast tumor samples at Uludag University Hospital in Turkey during the years 2018-2019, and its association with the clinicopathologic variables of patients was evaluated. Results: HSP90, SIAH1, and SIAH2 were significantly (P=0.0271, P=0.022, and P=0.0311) upregulated tumor tissue of patients with breast cancer. Moreover, this study observed a significant association between the high expression of SIAH2/HSP90 with ER status, high expression of HSP90 with Recurrence/Metastasis, and high expression of SIAH2 with Ki-67 proliferation index. Conclusion: The HSP90 and SIAH2 expressions play a significant role in breast cancer development by combining the experimental and clinical data obtained from the literature.

Skeletal muscle gene expression in older adults with type 2 diabetes mellitus undergoing calorie-restricted diet and recreational sports training - a randomized clinical trial.

AIMS: This study aimed to evaluate the impact of a 12-week calorie-restricted diet and recreational sports training on gene expressions IL-15, ATROGIN-1 and MURF-1 in skeletal muscle of T2D patients. METHODS: Older adults with T2D (n = 39, 60 ± 6.0 years, BMI 33.5 ± 0.6 kg/m2) were randomly allocated to Diet+Soccer (DS), Diet+Running (DR) or Diet (D). The training sessions were moderate-to-high-intensity and performed 3 × 40 min/week for 12-weeks. Gene expression from vastus lateralis muscle obtained by qRT-PCR, dual-energy X-ray and fasting blood testing measurements were performed before and after 12-weeks. Statistical analysis adopted were two-way ANOVA and Paired t-test for gene expression, and RM-ANOVA test for the remainder variables. RESULTS: Total body weight was reduced in ~4 kg representing body fat mass in all groups after 12-weeks (P < 0.05). HbA1c values decreased in all groups post-intervention. Lipids profile improved in the training groups (P < 0.05) after 12-weeks. ATROGIN-1 and MURF-1 mRNA reduced in the DS (1.084 ± 0.14 vs. 0.754 ± 1.14 and 1.175 ± 0.34 vs. 0.693 ± 0.12, respectively; P < 0.05), while IL-15 mRNA increased in the DR (1.056 ± 0.12 vs. 1.308 ± 0.13; P < 0.05) after 12-weeks intervention. CONCLUSION: Recreational training with a moderate calorie-restricted diet can downregulates the expression of atrophy-associated myokines and increases the expression of anti-inflammatory gene IL-15.

Effects of statins on the inducible degrader of low-density lipoprotein receptor in familial hypercholesterolemia.

The inducible degrader of low-density lipoprotein receptor (IDOL) is an E3 ubiquitin ligase involved in the post-transcriptional regulation of LDL receptor (LDLR). Statins lower plasma LDL by activating transcription of hepatic LDLR expression, and we have determined whether statins modulate IDOL expression and influence LDLR protein abundance. IDOL expression in monocytes and serum IDOL level was determined in statin-treated familial hypercholesterolemia (FH) patients and compared with control subjects. Serum IDOL level was also evaluated in a group of untreated FH patients before and after the initiation of statin. The mechanism underlying the inhibitory effect of statin on IDOL expression was investigated in vitro. In statin-treated FH patients, serum IDOL level and its expression in monocytes was reduced compared with control (P < 0.05). In contrast, untreated FH patients had higher serum levels of IDOL and proprotein convertase subtilisin/kexintype 9 (PCSK9) than control (P < 0.05), and serum IDOL level decreased after statin therapy (P < 0.05) whereas an increase was observed in PCSK9 level (P < 0.01). In vitro, atorvastatin significantly decreased IDOL abundance in a dose-dependent manner in cultured macrophages and hepatocytes with a concomitant increase in LDLR expression. The transcription of IDOL was restored by adding either an LXR agonist T0901317 or oxysterol 22(R)-hydroxycholesterol, indicating that statin inhibited IDOL expression by reducing LXR activation. The LXR-IDOL-LDLR axis can be modulated by statins in vitro and in vivo. Statins inhibit IDOL expression by reducing LXR activation and upregulate LDLR, and statins exert the opposite effect on IDOL and PCSK9.

Expression of neural precursor cell expressed developmentally downregulated 4-1 in pancreatic cancer tissue and its clinical significance / 临床肝胆病杂志

Objective To investigate the expression of the E3 ubiquitin ligase neural precursor cell expressed developmentally downregulated 4-1 (NEDD4-1) in pancreatic cancer tissue and its clinical significance. Methods Clinical data were collected from 58 patients who underwent surgical treatment in Xuzhou Central Hospital from January 2017 to December 2019 and were diagnosed with pancreatic ductal adenocarcinoma based on pathological examination. Immunohistochemistry was used to measure the expression of NEDD4-1 in pancreatic cancer tissue samples, and the association between the expression of NEDD4-1 and the clinicopathological features of pancreatic cancer was analyzed. Western blot was used to measure the protein expression level of NEDD4-1 in normal pancreatic ductal epithelial HPDE6-C7 cells and pancreatic cancer SW1990, BxPC-3, and PANC-1 cells. The t -test was used for comparison of continuous data between two groups, and the chi-square test was used for comparison of categorical data between two groups. The Kaplan-Meier method was used to plot survival curves, and the log-rank test was used for survival analysis. The Cox proportional-hazards regression model was used to investigate the factors associated with prognosis. Results The expression level of NEDD4-1 in pancreatic cancer tissue was significantly higher than that in adjacent tissue (79.31% vs 19.05%, χ 2 =35.614, P < 0.01), and the protein expression of NEDD4-1 in pancreatic cancer cells was significantly higher than that in normal pancreatic ductal epithelial cells ( P < 0.01). In the patients with pancreatic cancer, the expression of NEDD4-1 was associated with distant metastasis ( χ 2 =5.089, P =0.040), tumor differentiation ( χ 2 =9.071, P =0.003), and TNM stage ( χ 2 =8.882, P =0.003). The patients with high NEDD4-1 expression had a significantly shorter mean survival time than those with low expression (13.61±0.95 months vs 22.22±2.20 months, P =0.001). The Cox regression analysis showed that NEDD4-1 expression (hazard ratio [ HR ]=2.312, 95% confidence interval [ CI ]: 1.010-5.295, P =0.047), degree of tumor differentiation ( HR =2.981, 95% CI : 1.556-5.712, P =0.001), and lymph node metastasis ( HR =2.144, 95% CI : 1.155-3.979, P =0.016) were independent risk factors for the prognosis of patients with pancreatic cancer. Conclusion There is a significant increase in the expression of NEDD4-1 in pancreatic cancer tissue and cells, and the high expression of NEDD4-1 is associated with poor prognosis. Therefore, it can be used as a prognostic biomarker and a therapeutic target for pancreatic cancer.

Effect of c-CBL overexpression on activation of astrocytes in spinal cord of rats with neuropathic pain: relationship with Kindlin-1 / 中华麻醉学杂志

Objective:To evaluate the effect of c-CBL overexpression on activation of astrocytes in the spinal cord of rats with neuropathic pain and the relationship with Kindlin-1.Methods:Eighteen clean-grade healthy male Sprague-Dawley rats, aged 10-12 weeks, weighing 250-280 g, were divided into 3 groups ( n=6 each) using a random number table method: sham operation group (S group), neuropathic pain group (NP group) and c-CBL overexpression group (c-CBL group). The model of neuropathic pain was developed by chronic compression of the sciatic nerve in anesthetized rats.On 1 day before operation, c-CBL overexpression vector 10 μl was intrathecally injected in group c-CBL, while blank vehicle 10 μl was intrathecally injected in S and NP groups.The mechanical paw withdrawal threshold (MWT) and thermal paw withdrawal latency (TWL) were measured on 1 day before operation (T 0) and 1, 4 and 7 days after operation (T 1-3). The rats were sacrificed by decapitation after measurement of the pain threshold at T 3, and the spinal cord of L 4-6 was taken for determination of the expression of Kindlin-1, glial fibrillary acidic protein (GFAP), tumor necrosis factor-alpha (TNF-α), and interleukin-1beta (IL-1β) (by Western blot) and co-expression of Kindlin-1 with c-CBL (by co-immunoprecipitation). Results:Compared with group S, the MWT was significantly decreased and TWL was shortened at T 2, 3 in group NP and group c-CBL, the expression of Kindlin-1, GFAP, TNF-α and IL-1β was significantly up-regulated in group NP, and the expression of c-CBL was significantly up-regulated in group c-CBL ( P<0.05). Compared with group NP, the MWT was significantly increased and TWL was prolonged at T 2, 3, the expression of Kindlin-1, GFAP, TNF-α and IL-1β was down-regulated, and the expression of c-CBL was up-regulated in group c-CBL ( P<0.05). The results of co-immunoprecipitation showed that there was a protein interaction and co-expression relationship between Kindlin-1 and c-CBL in group NP, and the co-expression of Kindlin-1 with c-CBL was enhanced in group c-CBL when compared with group NP. Conclusions:The overexpression of c-CBL can inhibit activation of astrocytes by down-regulating the expression of Kindlin-1 in the spinal cord, thus reducing inflammatory responses and relieving neuropathic pain in rats.

Emerging roles of the HECT-type E3 ubiquitin ligases in hematological malignancies.

Ubiquitination-mediated proteolysis or regulation of proteins, ultimately executed by E3 ubiquitin ligases, control a wide array of cellular processes, including transcription, cell cycle, autophagy and apoptotic cell death. HECT-type E3 ubiquitin ligases can be distinguished from other subfamilies of E3 ubiquitin ligases because they have a C-terminal HECT domain that directly catalyzes the covalent attachment of ubiquitin to their substrate proteins. Deregulation of HECT-type E3-mediated ubiquitination plays a prominent role in cancer development and chemoresistance. Several members of this subfamily are indeed frequently deregulated in human cancers as a result of genetic mutations and altered expression or activity. HECT-type E3s contribute to tumorigenesis by regulating the ubiquitination rate of substrates that function as either tumour suppressors or oncogenes. While the pathological roles of the HECT family members in solid tumors are quite well established, their contribution to the pathogenesis of hematological malignancies has only recently emerged. This review aims to provide a comprehensive overview of the involvement of the HECT-type E3s in leukemogenesis.

WWP2 Promotes Odontoblastic Differentiation by Monoubiquitinating KLF5.

WW domain-containing E3 Ub-protein ligase 2 (WWP2) belongs to the homologous to E6AP C-terminus (HECT) E3 ligase family. It has been explored to regulate osteogenic differentiation, chondrogenesis, and palatogenesis. Odontoblasts are terminally differentiated mesenchymal cells, which contribute to dentin formation in tooth development. However, it remained unknown whether WWP2 participated in odontoblast differentiation. In this study, WWP2 was found to be expressed in mouse dental papilla cells (mDPCs), odontoblasts, and odontoblastic-induced mDPCs by immunohistochemistry and Western blotting. Besides, WWP2 expression was decreased in the cytoplasm but increased in the nuclei of differentiation-induced mDPCs. When Wwp2 was knocked down, the elevated expression of odontoblast marker genes (Dmp1 and Dspp) in mDPCs induced by differentiation medium was suppressed. Meanwhile, a decrease of alkaline phosphatase (ALP) activity was observed by ALP staining, and reduced formation of mineralized matrix nodules was demonstrated by Alizarin Red S staining. Overexpression of WWP2 presented opposite results to knockdown experiments, suggesting that WWP2 promoted odontoblastic differentiation of mDPCs. Further investigation found that WWP2 was coexpressed and interacted with KLF5 in the nuclei, leading to ubiquitination of KLF5. The PPPSY (PY2) motif of KLF5 was essential for its physical binding with WWP2. Also, cysteine 838 (Cys838) of WWP2 was the active site for ubiquitination of KLF5, which did not lead to proteolysis of KLF5. Then, KLF5 was confirmed to be monoubiquitinated and transactivated by WWP2, which promoted the expression of KLF5 downstream genes Dmp1 and Dspp. Deletion of the PY2 motif of KLF5 or mutation of Cys838 of WWP2 reduced the upregulation of Dmp1 and Dspp. Besides, lysine (K) residues K31, K52, K83, and K265 of KLF5 were verified to be crucial to WWP2-mediated KLF5 transactivation. Taken together, WWP2 promoted odontoblastic differentiation by monoubiquitinating KLF5.

Advances in the role of HECT-type E3 ubiquitin ligases in tumors / 国际外科学杂志

The occurrence and development of tumors is a complex process with multiple factors and multiple steps.Ubiquitination refers to a multi-step cascade of protein modification processes including ubiquitin,ubiquitin-activating enzyme,ubiquitin-binding enzyme,ubiquitin ligase and proteasome,which is important for maintaining eukaryotic homeostasis.mechanism.The E3 ubiquitin ligases family is an important component of the ubiquitin-proteasome system.This family includes many proteins that catalyze the ubiquitination of various protein substrates and promote their degradation by the proteasome system.Up to date,E3 ubiquitin ligases has played an important role in a variety of tumor cell biology processes,including cell proliferation,apoptosis and cycle regulation.HECT-type E3 ubiquitin ligases,one of the earliest studies of E3 ubiquitin ligases,is involved in the ubiquitination of transcriptional regulation of protein translation.This article reviews the recent research progress of HECT-type E3 ubiquitin ligases and its role in tumors.

Advances in the role of HECT-type E3 ubiquitin ligases in tumors / 国际外科学杂志

The occurrence and development of tumors is a complex process with multiple factors and multiple steps. Ubiquitination refers to a multi-step cascade of protein modification processes including ubiquitin, ubiquitin-activating enzyme, ubiquitin-binding enzyme, ubiquitin ligase and proteasome, which is important for maintaining eukaryotic homeostasis. mechanism. The E3 ubiquitin ligases family is an important component of the ubiquitin-proteasome system. This family includes many proteins that catalyze the ubiquitination of various protein substrates and promote their degradation by the proteasome system. Up to date, E3 ubiquitin ligases has played an important role in a variety of tumor cell biology processes, including cell proliferation, apoptosis and cycle regulation. HECT-type E3 ubiquitin ligases, one of the earliest studies of E3 ubiquitin ligases, is involved in the ubiquitination of transcriptional regulation of protein translation. This article reviews the recent research progress of HECT-type E3 ubiquitin ligases and its role in tumors.

Effect of ultraviolet and all-trans retinoic acid on expression of Hrd1 in human skin and fibroblasts / 中华皮肤科杂志

Objective To evaluate the effect of ultraviolet (UV) irradiation and all-trans retinoic acid (ATRA) on expression of Hrd1 in human skin and fibroblasts,and to explore their mechanisms.Methods From December 2017 to June 2018,12 human skin tissue samples were collected from Department of Dermatology,The First Affiliated Hospital of Nanjing Medical University,including 3 sun-exposed and 3 non-sun-exposed skin tissue samples of patients aged 30-40 years,and 3 sun-exposed and 3 non-sun-exposed skin tissue samples of patients aged 60-70 years.Immunohistochemicai examination was performed to determine the expression of Hrd 1 in the above samples.A total of 40 BALB/c mice were randomly classified into 4 groups:UV group treated with UVA irradiation at 10 J/cm2 and UVB irradiation at 30 mJ/cm2 every day,ATRA group topically treated with 0.1 ml of ATRA 0.1％ cream once a day on the shaved back,UV + ATRA group treated with topical ATRA 0.1％ cream before the above UV irradiation,and control group receiving no treatment.After 14 weeks,these mice were sacrificed,skin tissues were excised from the back,and the expression of Hrd 1 was determined by immunohistochemical examination.In vitro cultured human fibroblasts were divided into 4 groups:UV group and ATRA + UV group covered with phosphate buffer saline (PBS) followed by UVA irradiation at 10 J/cm2 or UVB irradiation at 30 mJ/cm2,ATRA group treated with culture media containing 1.μmol/L ATRA for 24 hours,and ATRA + UV group also treated with culture media containing 1 μmol/L ATRA for 24 hours after the ultraviolet irradiation.Western blot analysis was performed to determine the expression of Hrd 1 in fibroblasts in the above groups,fluorescence microscopy to detect the levels of reactive oxygen species (ROS) in the above groups.Statistical analysis was carried out by one-way analysis of variance (ANOVA) for comparison among groups,and least significant difference (LSD)-t test for multiple comparisons.The difference was considered to be statistically significant when the P value was less than the significant level of 0.05.Results In both the groups of 30-40 years and 60-70 years,the expression of Hrd1 was significantly higher in the sun-exposed skin tissues (0.307 ± 0.256,0.486 ± 0.579,respectively) than in the non-sun-exposed skin tissues (0.196 ± 0.330,0.199 ± 0.375,respectively;t =5.486,10.579 respectively,both P ＜ 0.05).In the in vivo experiment,the expression of Hrd1 in the skin tissues of mice significantly differed among the control group,UV group,ATRA group and ATRA + UV group (0.189 ± 0.015,0.288 ± 0.017,0.187 ±0.020,0.226 ± 0.021 respectively,F =19.553,P ＜ 0.001),and the UV group showed significantly higher Hrd1 expression compared with the control group (t =5.337,P =0.033)and ATRA + UV group (t =4.891,P =0.039).In the in vitro experiment,the level of Hrd1 in the fibroblasts significantly differed among the 4 groups after the UVA or UVB irradiation (F =120.704,102.119,both P ＜ 0.001).The effect of the UVA and UVB irradiation on the expression of Hrd1 was basically consistent,and the Hrd1 level was significantly higher in the UV group than in the control group and ATRA + UV group (both P ＜ 0.05).After the UV irradiation,the ROS level was significantly higher in the UV group than in the control group and ATRA + UV group (both P ＜ 0.05).Conclusion ATRA can inhibit ultraviolet-induced Hrd1 expression in skin fibroblasts,likely by inhibiting the generation of cellular ROS.

Role of autophagy in Parkin over-expression-induced reduction of cardiac hypertrophy in diabetic rats / 中华麻醉学杂志

Objective To evaluate the role of autophagy in Parkin over-expression-induced reduction of cardiac hypertrophy in diabetic rats.Methods Thirty-two healthy SPF male Sprague-Dawley rats,aged 2 months,weighing 200-230 g,were divided into 4 groups (n =8 each) using a random number table method:non-diabetes mellitus (DM) group (group Non-DM),DM group,DM plus AAV9-CMV-Parkin group (group DM+P) and DM puls AAV9-CMV-Parkin puls autophagy inhibitor 3-methyladenine (3-MA) group (group DM+P+MA).DM was induced by intraperitoneal streptozotocin (STZ) 60 mg/kg and confirmed by blood glucose level ＞16.7 mmol/L,and Parkin overexpression was achieved with adeno-associated virus serotype 9 as a vector.AAV9-CMV-Parkin 1 × 1012 mg/kg was injected into the tail vein at 3 weeks after STZ injection in group DM+P.In group DM+P+MA,AAV9-CMV-Parkin 1× 1012 mg/kg was injected into the tail vein at 3 weeks after STZ injection,and 3 weeks later 3-MA 15 mg/kg was injected into the tail vein,once a week for 6 weeks in total.Cardiac diastolic and systolic function was detected using Bmode ultrasonography.Cardiomyocytes were obtained for microscopic examination of the cross-sectional area (with a light microscope) and for determination of the expression of microtubule-associated protein 1 light chain 3,P62 and Parkin.Results Compared with group Non-DM,the cross-sectional area of cardiomyocytes was significantly increased,and the diastolic and systolic function was decreased in DM group (P＜0.05).Compared with group DM,the cross-sectional area of cardiomyocytes was significantly decreased,the diastolic and systolic function was improved,the expression of microtubule-associated protein 1 light chain 3 and Parkin in myocardial tissues was up-regulated,and the expression of P62 was down-regulated in group DM+P (P＜0.05).Compared with group MD+P,the cross-sectional area of cardiomyocytes was significantly increased,the diastolic and systolic function was decreased,the expression of microtubule-associated protein 1 light chain 3 was down-regulated,and the expression of P62 was up-regulated in group DM+P+MA (P＜0.05) Conclusion Autophagy is involved in Parkin over-expression-induced reduction of cardiac hypertrophy in diabetic rats.

Genome-Wide Identification and Analysis of U-Box E3 Ubiquitin⁻Protein Ligase Gene Family in Banana.

The U-box gene family is a family of genes which encode U-box domain-containing proteins. However, little is known about U-box genes in banana (Musa acuminata). In this study, 91 U-box genes were identified in banana based on its genome sequence. The banana U-box genes were distributed across all 12 chromosomes at different densities. Phylogenetic analysis of U-box genes from banana, Arabidopsis, and rice suggested that they can be clustered into seven subgroups (I⁻VII), and most U-box genes had a closer relationship between banana and rice relative to Arabidopsis. Typical U-box domains were found in all identified MaU-box genes through the analysis of conserved motifs. Four conserved domains were found in major banana U-box proteins. The MaU-box gene family had the highest expression in the roots at the initial fruit developmental stage. The MaU-box genes exhibited stronger response to drought than to salt and low temperatures. To the best of our knowledge, this report is the first to perform genome-wide identification and analysis of the U-box gene family in banana, and the results should provide valuable information for better understanding of the function of U-box in banana.

Protein Quality Control Degradation in the Nucleus.

Nuclear proteins participate in diverse cellular processes, many of which are essential for cell survival and viability. To maintain optimal nuclear physiology, the cell employs the ubiquitin-proteasome system to eliminate damaged and misfolded proteins in the nucleus that could otherwise harm the cell. In this review, we highlight the current knowledge about the major ubiquitin-protein ligases involved in protein quality control degradation (PQCD) in the nucleus and how they orchestrate their functions to eliminate misfolded proteins in different nuclear subcompartments. Many human disorders are causally linked to protein misfolding in the nucleus, hence we discuss major concepts that still need to be clarified to better understand the basis of the nuclear misfolded proteins' toxic effects. Additionally, we touch upon potential strategies for manipulating nuclear PQCD pathways to ameliorate diseases associated with protein misfolding and aggregation in the nucleus.

Inactivation of the E3 Ubiquitin Ligase IDOL Attenuates Diet-Induced Obesity and Metabolic Dysfunction in Mice.

Objective- The E3 ubiquitin ligase IDOL (inducible degrader of the LDLR [LDL (low-density lipoprotein) receptor]) is a post-transcriptional regulator of LDLR abundance. Model systems and human genetics support a role for IDOL in regulating circulating LDL levels. Whether IDOL plays a broader metabolic role and affects development of metabolic syndrome-associated comorbidities is unknown. Approach and Results- We studied WT (wild type) and Idol(-/-) (Idol-KO) mice in 2 models: physiological aging and diet-induced obesity. In both models, deletion of Idol protected mice from metabolic dysfunction. On a Western-type diet, Idol loss resulted in decreased circulating levels of cholesterol, triglycerides, glucose, and insulin. This was accompanied by protection from weight gain in short- and long-term dietary challenges, which could be attributed to reduced hepatosteatosis and fat mass in Idol-KO mice. Although feeding and intestinal fat uptake were unchanged in Idol-KO mice, their brown adipose tissue was protected from lipid accumulation and had elevated expression of UCP1 (uncoupling protein 1) and TH (tyrosine hydroxylase). Indirect calorimetry indicated a marked increase in locomotion and suggested a trend toward increased cumulative energy expenditure and fat oxidation. An increase in in vivo clearance of reconstituted lipoprotein particles in Idol-KO mice may sustain this energetic demand. In the BXD mouse genetic reference population, hepatic Idol expression correlates with multiple metabolic parameters, thus providing support for findings in the Idol-KO mice. Conclusions- Our study uncovers an unrecognized role for Idol in regulation of whole body metabolism in physiological aging and on a Western-type diet. These findings support Idol inhibition as a therapeutic strategy to target multiple metabolic syndrome-associated comorbidities.

Role of ubiquitin ligase FBW7 in the sensitivity of glioma to temozolomide and its mechanism / 肿瘤研究与临床

Objective To study the role of ubiquitin ligase FBW7 in the sensitivity of glioma to temozolomide and its mechanism in glioma cells. Methods FBW7 overexpression lentivirus was constructed. Glioma cell line U251 was divided into 4 groups: the control group, temozolomide group, FBW7 overexpression group, and FBW7 overexpression + temozolomide group. Compared with the intervention on U251 cell lines, the differences of cell inhibitory rates in 4 different groups were analyzed by using contrast microscopy and methyl thiazolyl tetrazolium (MTT) colorimetric assay after 36 h and 72 h respectively. Flow cytometry (FC) was used to determine the cell cycle and apoptosis rate. Results The survival number of U251 cells in the three treatment groups was increased compared with the control group at both 36 h and 72 h. The inhibitory rates of temozolomide group, FBW7 overexpression group, and FBW7 overexpression +temozolomide group at 36 h were (17.6±0.8) ％, (10.4±0.6) ％, (18.6±0.6) ％ respectively compared with the control group (F=67.02, P<0.01); while at 72 h, the inhibitory rates of the three treatment groups were (25.1 ±0.4) ％, (16.7 ±0.7) ％, (29.0 ±0.9) ％ respectively compared with the control group (F= 74.61, P<0.001). Moreover, FBW7 overexpression + temozolomide group presented much greater inhibitory rate than temozolomide group (P<0.01). The G2/M arrest ratio and the cell apoptotic rate at 72 h in the three treatment groups were higher than those in the control group (F=41.63, P<0.001;F=42.30, P<0.01). The increased degree of G2/M arrest ratio and the cell apoptotic rate in FBW7 overexpression + temozolomide group were more obvious compared with temozolomide group (P<0.05, P<0.01). Conclusion FBW7 could enhance the sensitivity of glioma cells to temozolomide treatment, which is associated with G 2/M arrest and the increased apoptosis rate induced by FBW7.

Progress of relationship between ubiquitinating enzyme damaged-DNA binding protein 2 and tumors / 肿瘤研究与临床

Ubiquitinating enzyme damaged-DNA binding protein 2 (DDB2) is a rind of DDB1 and CUL4-associated factors (DCAF), and identifies belonging to the family of ubiquitinating E3 enzymes. DDB2 combines with CUL4-DDB1 to form the ubiquitin ligase complex, and identifies targets protein substrate specificity to make the substrate ubiquitin and degradation. It affects the development of tumors through various pathways, such as DNA damage repair, cell cycle regulation and apoptosis, cell invasion and metastasis, cell premature senescence, cell proliferation and cancer stem cell population. This paper reviews the progress of the relationship between DDB2 and the development, treatment and prognosis judgment of tumors.