Effects of bone marrow mesenchymal stem cell transplantation on bone metabolism and RANKL/OPG/TRAF6 signaling pathway in osteoporotic rats / 中华内分泌外科杂志

Objective:To investigate the effect of bone marrow derived mesenchymal stem cells (BMSC) transplantation on bone metabolism and its mechanism in ovariectomized osteoporosis rats.Methods:Forty clean SD female rats aged 7 weeks were divided into 4 groups according to the random number table method: sham operation group, model group, the transplantation group, positive control group, in addition to control the rest of the group were performed bilateral oophorectomy build osteoporosis rats model, after 2 months of model establishment, rats in transplantation group were injected with 80 μl/kg PBS solution containing bone marrow mesenchymal stem cells through tail vein, rats in sham operation group and model group were injected with the same amount of PBS solution through tail vein, and rats in positive control group were given Xianlinggubao (0.5 g/100 g) by gavage every day. Serum and femur were collected 14 days after treatment. Hematoxylin and eosin staining (HE) was used to observe the histopathological changes of femur. Micro-CT was used to measure bone mineral density and bone parameters. The expression levels of osteocalcin, osteoprotegerin, alkaline phosphatase and insulin-like growth factor 1 were detected by enzyme-linked immunosorbent assay (ELISA) kit. The serum levels of calcium, phosphorus and magnesium were measured by spectrophotometer. The protein expressions of RANKL, OPG, TRAF6 and NF-KB1 in femur of each group were detected by Western blot.Results:Compared with the sham operation group, the bone mineral density (BMD) of the model group was decreased by (0.28±0.01) g/cm 3, bone volume fraction (BMD) was decreased by (0.28±0.01) g/cm 3. BV/TV) decreased by (19.73±2.02) %, trabecular thickness (Tb.Th) decreased by (0.082±0.008) mm, trabecular number (Tb.N) decreased by (1.60±0.17) mm -1 and trabecular separation/spacing (Tb.Sp) increased (0.273±0.024) mm, osteoprotegerin (489.49±55.29) ng/L, alkaline phosphatase (229.13±15.05) U/L, insulin-like growth factor-1 (236.64±14.32) μg/L, and osteocalcin were decreased (1.866±0.109) μg/L, calcium (11.98±1.09) mg/dl, phosphorus (6.85±0.68) mg/dl, and magnesium decreased (0.62±0.04) mg/dl) , the relative expression level of RANKL increased (1.05±0.09) , the relative expression level of OPG decreased (0.58±0.08) , the relative expression level of RANKL increased (0.74±0.10) , and the relative expression level of NF-kB1 increased (1.01±0.11) ( P<0.05) ; bone mineral density, bone mineral density, bone mineral density BMD (0.38±0.04 g/cm 3, BV/TV (26.73±2.74) %, Tb.Th (0.094±0.006) mm, Tb.N (2.67±0.09) mm-1 and Tb.Sp were decreased (0.241±0.026) mm) , osteoprotegerin (720.09±67.41) ng/L, alkaline phosphatase (269.48±14.15) U/L, insulin-like growth factor 1 (IGF-1) decreased (335.95±24.13) μg/L, and osteocalcin increased (1.392±0.153) μg/L, calcium (7.12±0.53) mg/dl, phosphorus (4.54±0.32) mg/dl, magnesium (0.87±0.08) mg/dl. RANKL relative expression level increased (0.59±0.05) , OPG relative expression level decreased (0.97±0.10) , RANKL relative expression level increased (0.45±0.06) , NF-kB1 relative expression level increased (0.72±0.06) ( P<0.05) ;bone mineral density, bone mineral density, bone mineral density BMD (0.36±0.05) g/cm 3, BV/TV (28.72±3.20) %, Tb.Th (0.096±0.011) mm, Tb.N (2.85±0.24) mm -1 Tb.Sp was basically unchanged (0.241±0.027) mm, osteoprotegerin was decreased (716.78±36.90) ng/L, alkaline phosphatase was basically unchanged (270.65±18.59) U/L, and insulin-like growth factor 1 was decreased (336.94±17.50) μg/L, osteocalcin (1.377±0.101) μg/L, calcium (7.13±0.80) mg/dl, phosphorus (4.58±0.71) mg/dl, and magnesium (0.89±0.04) remained unchanged mg/dl, the relative expression level of RANKL increased (0.55±0.08) , the relative expression level of OPG decreased (0.98±0.13) , the relative expression level of RANKL was basically unchanged (0.40±0.05) , and the relative expression level of NF-kB1 increased (0.65±0.09) ( P<0.05) . Conclusion:Bone marrow mesenchymal stem cell transplantation can improve osteoporosis in ovariectomized rats by regulating bone metabolism and serum levels of calcium, phosphorus and magnesium, which may be related to RANKL/OPG/TRAF6 pathway.

Dahuang Lingxian Prescription Regulates Effect of TAK1 and TRAF6 Interaction and Co-localization on Inflammatory Response of Bile Duct Cells / 中国实验方剂学杂志

ObjectiveTo observe the repair effect of Dahuanglingxian prescription （DHLX） on bile duct epithelial cells of rats. To explore whether its mechanism of action is to adjust the mutual binding of transforming growth factor -β （TGF-β） activated kinase 1（TAK1） and tumor necrosis factor receptor-associated factor 6 （TRAF6）， and regulate the activation of the nuclear transcription factor -κB （NF-κB）/mitogen-activated protein kinase （MAPK） signaling pathway. MethodThe 20 SD rats were randomly divided into normal group and DHLX group， 10 rats in each group， were given saline and DHLX （320 mg·kg-1·d-1） for 8 days， to prepare normal serum and DHLX serum. Biliary epithelial cells were extracted from normal SD rats and divided into 9 groups： Normal group， model group （20 mg·L-1）， LPS+DHLX group （20 mg·L-1+10% DHLX）， LPS+PDTC group （20 mg·L-1+200 μmol·L-1）， LPS+SB203580 group （20 mg·L-1+0.5 μmol·L-1）， LPS+PDTC+SB203580 group （20 mg·L-1+200 μmol·L-1+0.5 μmol·L-1）， LPS+PDTC+DHLX group （20 mg·L-1+200 μmol·L-1+10% DHLX serum）， LPS+SB203580+DHLX group （20 mg·L-1+0.5 μmol·L-1+10% DHLX serum）， LPS+PDTC+SB203580 +DHLX group （20 mg·L-1+200 μmol·L-1+0.5 μmol·L-1+10% DHLX serum）. The microscopic observation of morphological changes in each group of cells after drug intervention. Enzyme-linked immunosorbent assay（ELISA） was used to detect the expression of （IL）-1β and IL-6 in each group of cells. Western blot detected the expression levels of TAK1 and TRAF6 proteins in each group of cells， Co-IP detected the interaction between TAK1 and TRAF6， and further observed the distribution and co-localization of TAK1 and TRAF6 using Laser confocal microscope. ResultAfter the action of LPS， the cell synapses are reduced， the cell body becomes significantly rounded and smaller， but the cell morphology of each group tends to be normal after medication. Compared with normal group， the expression levels of IL-1β and IL-6 in model group were significantly increased （P<0.05）， while the expression level of TAK1 was decreased while the expression level of TRAF6 was increased （P<0.05）. The content of TAK1-TRAF6 protein complex showed a decreasing trend， and the two proteins co-located in the cytoplasm. Compared with model group， the expression levels of IL-1β and IL-6 in LPS+DHLX group were significantly decreased （P<0.05）， the expression level of TAK1 was increased and the expression level of TRAF6 was decreased （P<0.05）， the content of TAK1-TRAF6 protein complex was significantly increased （P<0.01）， and the two proteins were significantly co-located in cytoplasm. Compared with LPS+DHLX group， the expression levels of IL-1β and IL-6 in other groups were significantly decreased （P<0.05，P<0.01）. TAK1-TRAF6 protein complex content in each group was significantly decreased after pathway blocker intervention （P<0.05）， while TAK1-TRAF6 protein complex content in each group was significantly increased after pathway blocker combined with DHLX intervention （P<0.05）. Co-localization of the TAK1-TRAF6 in cytoplasm was not obvious. ConclusionIn the LPS-induced inflammatory response of bile duct cells， the binding of TAK1 and TRAF6 showed a weakening trend， but DHLX could reverse the phenomenon， we think the mechanism of action may be related to promoting the mutual binding of TAK1 and TARF6 to inhibit the activation of the NF-κB/MAPK signaling pathway.

TRAF6/ERK/p38 pathway is involved in interleukin-17-mediated autophagy to promote osteoclast precursor cell differentiation / 浙江大学学报·医学版

To investigate the effects of interleukin (IL)-17-mediated autophagy on the TNF receptor associated factor (TRAF6)/extracellular signal-regulated kinase (ERK)/p38 pathway and osteoclast differentiation. Mouse bone marrow-derived macrophages (BMM) were cultured with a medium containing 30 ng/mL macrophage colony stimulating factor and 50 ng/mL receptor activator of nuclear factor-kappa B ligard (RANKL), and IL-17 (0.01, 0.1, 1.0, 10 ng/mL) was added for intervention (IL-17 group). Tartrate-resistant acid phosphatase (TRAP) staining was used to observe TRAP positive multinucleated cells; phalloidin fluorescent staining was used to detect actin ring circumference; toluidine blue staining was used to analyze bone resorption lacuna formation. To further examine the mechanism of the effect of IL-17-mediated autophagy on the differentiation of osteoclasts, the control group used RANKL medium to culture mouse macrophage RAW264.7 cells, while the IL-17 group was treated with IL-17 (0.01, 0.1, 1.0, /mL). Western blot was used to detect the expression of autophagy-related proteins Beclin-1, microtubule-associated protein 1 light chain 3 (LC3) and osteoclast-related proteins c-fos and nuclear factor of activated T cell 1 (NFATc1) after treatment with different concentrations of IL-17. The expression of LC3, NFATc1, TRAF6/ERK/p38 signaling pathway related proteins were detected in IL-17 and autophagy inhibitor 3-MA group. The number of TRAP positive multinucleated cells, the circumference of the actin ring and the area of bone resorption lacuna in IL-17 group treated with IL-17 (0.01, 0.1, were significantly higher than those in the control group. In IL-17 treated RAW264.7 cells, the expression of c-fos, NFATc1, Beclin-1, LC3, TRAF6, p-ERK, and p-p38 was all significantly up-regulated (all 0.05). After treatment with the autophagy inhibitor 3-MA, the expression levels of LC3, NFATc1, TRAF6, p-ERK, and p-p38 all decreased significantly (all 0.05). IL-17 can promote the expression of autophagy proteins and enhance the differentiation ability of osteoclast precursor cells, and the TRAF6/ERK/p38 signaling pathway may be involved in this process.

Effects of Anchang Decoction on TLR 4/NF-κB Signaling Pathway and the Expression of Fecal Calprotectin in Rats with Ulcerative Colitis Induced by TNBS / 中国药房

OBJECTIVE：To st udy the effects of Anchang decoction on TLR 4/NF-κB signaling pathway and the expression of fecal calprotectin （FC）in TNBS-induced ulcerative colitis （UC）model rats . METHODS ：SD rats were randomly divided into blank group ，model group ，positive control group [Live Bifidobacterium capsules ，5 mL（containing Bifidobacterium 0.35 g）]， Anchang decoction low -dose，medium-dose and high-dose groups （1，5，10 mL，each milliliter is approximately equivalent to 0.11 g of total crude drug ），with 15 rats in each group. Other groups were given TNBS combined with ethanol enema to establish UC model rat ，except blank group was given normal saline. Two days after successful modeling ，blank group and model group were given normal saline 5 mL，administration groups were given relevant medicine intragastrically ，once a day ，for consecutive 14 d. After last medication ，HE staining was used to observe the pathological change of colon tissue in rats. Western blotting assay was used to detect the protein expression of TLR 4，TRAF6 and NF-κB in colon tissues of rats；Real-time fluorescent quantitative PCR was used to detect mRNA expression of TLR 4，TRAF6，TNF-α and NF-κB；ELISA assay was adopted to detect serum level of TNF-α，IL-6 and FC in stool samples. RESULTS ：Compared with blank group ，the colonic mucosa of model group was severely damaged，and the protein expression of TLR 4，TRAF6 and NF-κB，mRNA expression of TLR 4，TRAF6，TNF-α and NF-κb as well as serum levels of TNF-α，IL-6 and FC level in stool samples were increased significantly （P＜0.05）. Compared with model group，the pathological changes of colon tissue in rats were improved in different administration groups to different extents ，and above indexes were all decreased significantly （P＜0.05）. CONCLUSIONS ：Anchang decoction may relieve the inflammation of UC model rats by regulating the TLR 4/NF-κB signaling pathway and the expression of FC.

Norlichexanthone purified from plant endophyte prevents postmenopausal osteoporosis by targeting ER

Although different types of drugs are available for postmenopausal osteoporosis, the limitations of the current therapies including drug resistances and adverse effects require identification of novel anti-osteoporosis agents. Here, we defined that norlichexanthone (NOR), a natural product, is a ligand of estrogen receptor-alpha (ER

Sirt1-ROS-TRAF6 Signaling-Induced Pyroptosis Contributes to Early Injury in Ischemic Mice / 神经科学通报·英文版

Stroke is an acute cerebro-vascular disease with high incidence and poor prognosis, most commonly ischemic in nature. In recent years, increasing attention has been paid to inflammatory reactions as symptoms of a stroke. However, the role of inflammation in stroke and its underlying mechanisms require exploration. In this study, we evaluated the inflammatory reactions induced by acute ischemia and found that pyroptosis occurred after acute ischemia both in vivo and in vitro, as determined by interleukin-1β, apoptosis-associated speck-like protein, and caspase-1. The early inflammation resulted in irreversible ischemic injury, indicating that it deserves thorough investigation. Meanwhile, acute ischemia decreased the Sirtuin 1 (Sirt1) protein levels, and increased the TRAF6 (TNF receptor associated factor 6) protein and reactive oxygen species (ROS) levels. In further exploration, both Sirt1 suppression and TRAF6 activation were found to contribute to this pyroptosis. Reduced Sirt1 levels were responsible for the production of ROS and increased TRAF6 protein levels after ischemic exposure. Moreover, N-acetyl-L-cysteine, an ROS scavenger, suppressed the TRAF6 accumulation induced by oxygen-glucose deprivation via suppression of ROS bursts. These phenomena indicate that Sirt1 is upstream of ROS, and ROS bursts result in increased TRAF6 levels. Further, the activation of Sirt1 during the period of ischemia reduced ischemia-induced injury after 72 h of reperfusion in mice with middle cerebral artery occlusion. In sum, these results indicate that pyroptosis-dependent machinery contributes to the neural injury during acute ischemia via the Sirt1-ROS-TRAF6 signaling pathway. We propose that inflammatory reactions occur soon after oxidative stress and are detrimental to neuronal survival; this provides a promising therapeutic target against ischemic injuries such as a stroke.

p62 Negatively Regulates TLR4 Signaling via Functional Regulation of the TRAF6-ECSIT Complex

Sequestosome 1 (SQSTM1, p62), a ubiquitin binding protein, plays a role in cell signaling, oxidative stress, and autophagy. However, its functional role in inflammatory signaling is controversial. Recent studies have shown that p62 is negatively implicated in inflammatory responses. But, the precise molecular mechanisms by which p62 regulates inflammatory responses remain unclear. In this study, we report on a new regulatory role for p62 in TLR4-mediated signaling. p62 overexpression led to the suppression of NF-κB activation and the production of pro-inflammatory cytokines, TNF-α, IL-6, and IL-1β in response to TLR4 stimulation. In contrast, p62(−/−) mouse embryonic fibroblast (MEF) cells exhibited marked enhancement of NF-κB activation and production of pro-inflammatory cytokines by TLR4 stimulation, compared to p62(+/+) MEF cells. Additionally, the TLR4-induced activation of signal transduction was significantly augmented in p62(−/−) MEF cells, indicating that p62 was negatively implicated in TLR4-mediated signaling. Biochemical studies revealed that p62 interacted with the internal domain of evolutionarily conserved signaling intermediate in Toll pathways (ECSIT), which is critical for associating with the TNF receptor associated factor 6 (TRAF6)-ECSIT complex to activate NF-κB in TLR4 signaling. Interestingly, p62-ECSIT interaction inhibited the interaction between TRAF6 and ECSIT and attenuated the ubiquitination of ECSIT. Furthermore, upon LPS challenge, the mortality of p62(−/−) (p62-knockout) mice was markedly enhanced compared to p62(+/+) (p62 wild-type) mice. Taken together, our data demonstrate that p62 negatively regulated TLR4 signaling via functional regulation of the TRAF6-ECSIT complex.

Role of TRAF6 in inflammatory responses of human osteoblast-like cells with Enterococcusfaecalis / 口腔疾病防治

Objective @#Explore the role and status of tumor necrosis factor receptor-associated factor 6 (TRAF6) in the inflammatory response of human osteoblast-like cells MG63 which was triggered by Enterococcus faecalis (E. faecalis) and its lipoteichoic acid (LTA)@*Methods@# SiRNA technology was applied to silence the TRAF6 gene of MG63 cells, Using E.faecelis and its LTA to stimulate the silence MG63 cells with different hours. After that, using real-time PCR technology to detect toll-like receptor 2 (TLR2) and TRAF6 gene expression and using ELISA assay to detect proinflammatory cytokines interleukin-1β and TNF-alpha expression levels.@*Results@#When MG63 cells was infected by E. faecalis, its LTA, TLR2 and TRAF6 gene level has increased to varying degrees (P< 0.05); interleukin-1β and TNF-alpha expression was significantly higher (P< 0.05). When TRAF6 gene of MG63 cells was silenced by siRNA, pro-inflammatory cytokines interleukin-1β, interleukin-6, interleukin -8 and TNF-alpha expression decreased significantly (P< 0.05).@*Conclusion@#E. faecalis and its toxic components is identified by MG63 cells mainly through TLR2 receptors. The major virulence factor in periapical infections caused by E. faecalis is LTA.

Azithromycin inhibits proliferation of rat airway smooth muscle cells though TRAF6/NF-κB/VEGF signaling pathway / 重庆医学

Objective To explore the mechanism of azithromycin (AZM) for inhibiting the proliferation of rat airway smooth muscle cells (ASMCs).Methods Thirty Sprague-Dawley (SD) rats were divided into the control group,asthma model group and AZM group.The rat model of asthma was established by ovalbumin (OVA) sensitization and stimulation in vitro.The airway related parameters of rat lung tissue were determined by using the medical image analysis system.Primary passage ASMCs were isolated and cultured using the tissue-sticking method,and the vascular endothelial growth factor (VEGF) overexpression vector or tumor necrosis factor receptor-associated factor 6 (TRAF6) overexpression vector was transfected into ASMCs in the AZM group.The protein levels of VEGF,NF-κB p65 and TRAF6 were detected by Western blotting,and the proliferation of ASMCs was evaluated by CCK-8 kit.Results AZM significantly inhibited the increase of thickness of total airway wall,thickness of inner airway wall and thickness of airway smooth muscle layer in asthma rats (P<0.05),also significantly inhibited the proliferation of ASMCs in the asthma model group (P<0.05).AZM significantly inhibited the protein expression of VEGF and NF-κB p65 induced by asthma (P<0.05),and the overexpression of VEGF significantly reduced the inhibiting effects of AZM on proliferation of ASMCs (P<0.05).AZM significantly inhibited the high expression of TRAF6 induced by asthma (P<0.05),and the overexpression of TRAF6 significantly reduced the inhibiting effects of AZM on expression of VEGF and NF-κB p65 as well as proliferation of ASMCs (P<0.05).Conclusion AZM can suppress the proliferation of ASMCs,its partial mechanism may be realized through inhibiting TRAF6/NF-κB/VEGF signaling pathway.

Increased Expression of miR-146a in Children With Allergic Rhinitis After Allergen-Specific Immunotherapy

PURPOSE: MicroRNAs (miRs) were recently recognized to be important for immune cell differentiation and immune regulation. However, whether miRs were involved in allergen-specific immunotherapy (SIT) remains largely unknown. This study sought to examine changes in miR-146a and T regulatory cells in children with persistent allergic rhinitis (AR) after 3 months of subcutaneous immunotherapy (SCIT) and sublingual immunotherapy (SLIT). METHODS: Twenty-four HDM-sensitized children with persistent AR were enrolled and treated with SCIT (n=13) or SLIT (n=11) for 3 months. Relative miR-146a and Foxp3 mRNA expression, the TRAF6 protein level, and the ratio of post-treatment to baseline IL-10+CD4+ T cells between the SCIT and SLIT groups were examined in the peripheral blood mononuclear cells (PBMCs) of AR patients using quantitative reverse transcription polymerase chain reaction (qRT-PCR), flow cytometry, and Western blot analysis, respectively. Serum levels of IL-5 and IL-10 were determined using ELISA. RESULTS: After 3 months of SIT, both the TNSS and INSS scores were significantly decreased compared to the baseline value (P<0.01). The relative expression of miR-146a and Foxp3 mRNA was significantly increased after both SCIT and SLIT (P<0.01). The ratio of post-treatment to baseline IL-10+CD4+ T cells and the serum IL-10 level were significantly increased in both the SCIT and SLIT groups (P<0.01), whereas the TRAF6 protein level and serum IL-5 level were significantly decreased (P<0.01). No significant differences in these biomarkers were observed between the SCIT and SLIT groups. CONCLUSIONS: Our findings suggest that miR-146a and its related biomarkers may be comparably modulated after both SCIT and SLIT, highlighting miR-146a as a potential therapeutic target for the improved management of AR.

Expression and clinical significance of TRAF6 in patients with esophageal cancer / 中国免疫学杂志

Objective:To examine the expression of TRAF6 in esophageal organization from protein level and analyze the correlations between TRAF6 expression and clinical features.Methods: Seventy-eight patients with esophageal adenocarcinoma who were admitted to the Department of Oncology , Henan Province Hospital of TCM from January 2005 and January 2010 were finally eligible for present study and the corresponding esophageal normal tissues and clinical data were collected .All the specimens were confirmed by pathology for esophageal squamous cell carcinoma or esophageal normal tissues .The expression of TRAF6 in the tissue samples was detected by immunohistochemistry .The correlation between the TRAF6 expression and clinical characteristics of patients was analyzed.Results:The positive expression rate of TRAF 6 in esophageal cancer organizations and normal esophageal mucosal tissues were 71.79%and 10.26%,respectively.The positive expression rate of TRAF6 in esophageal cancer were significantly higher than those in normal esophageal mucosal tissue ( P0.05),but with lymph node metastasis and clinical stage (P<0.05).Patients with positive TRAF6 expression had significantly lower five-year survival rate than those with tumors having positive TAK1 expression.Conclusion:TRAF6 may play an important role in the pathology and development of squamous cell carcinoma ,and could be an important therapeutic target in the treatment of esophageal cancer .

Expression of TRAF6 and its correlation with clinicopathologic characteristics in ovarian carcinomas / 中国免疫学杂志

Objective:To examine the expression of TRAF 6 in ovarian carcinomas ,discuss the relation between expression level and clinical characteristics of ovarian carcinomas and study the clinical significance .Methods: Specimens from 102 patients with ovarian carcinomas managed in our hospital between Augest 2001 and December 2009 were included in this study .Immunohistochemical staining was used to detect the expression of TRAF 6 in ovarian carcinomas and normal tissues .All the specimens were confirmed by pa-thology for ovarian carcinomas and normal tissues by HE staining .Then, the correlation between the expression and clinical characteristics of patients was analyzed .Furthermore ,survival analyses were performed according to the Kaplan-Meier method.Results:The positive expression rate of TRAF 6 in ovarian carcinomas and normal tissues was 68.6% and 20.5%, respectively.TRAF6 expression was significantly associated with tumor stage and distant metastasis ( P<0.05 ) .According to the survival analysis of 102 ovarian carcinomas patients ,cases in the TRAF6 low-expression group showed poorer overall survival rate when compared with low -expression group ( P<0.001 ) .Conclusion: These results indicate that the expression of TRAF 6 was closely related with in the progression of ovarian carcinomas and may have clinical utility in the prediction of prognosis of ovarian carcinomas .

Role of TRAF6 in NF-?B and AP-1 signaling transduction pathway in human B lymphoma cell line / 基础医学与临床

Objective To investigate the role of TRAF6 in NF-?B and AP-1 signaling pathway in human B cell line.Methods Human Ramos B cells were transfected with plasmids expressing YFP fusion dominant-negative TRAF6(DN-TRAF6),or transfected with shRNA-TRAF6 plasmid.After incubation overnight,cells were either sorted with flowcytometry or screened by G418.Activation of NF-?B and AP-1 pathway,including phosphorylation of I?B?,ERK,JNK and P38,as well as nuclear translocation of NF-?B subunits(P65,P50 and c-Rel)and AP-1 subunits(C-FOS,C-JUN,CREB and ATF) were detected by Western blot and ELISA.Results In cells which overexpress DN-TRAF6 or endogenous TRAF6 expression were knocked-down by shRNA,the phosphorylation of I?B?,as well as phosphorylation of JNK were inhibited.Furthermore,nuclear translocation of NF-?B subunits P65,P50,c-Rel,and AP-1 subunits C-FOS and C-JUN were also inhibited in B cells through overexpression of DN-TRAF6.Conclusion TRAF6 selectively activates some kinases in CD40 mediated NF-?B and AP-1 signaling pathway,and plays an important role in their activation.

Identification of a Variant Form of Cellular Inhibitor of Apoptosis Protein (c-IAP2) That Contains a Disrupted Ring Domain

Among the members of the inhibitor of apoptosis (IAP) protein family, only Livin and survivin have been reported to have variant forms. We have found a variant form of c-IAP2 through the interaction with the X protein of HBV using the yeast two-hybrid system. In contrast to the wild-type c-IAP2, the variant form has two stretches of sequence in the RING domain that are repeated in the C-terminus that would disrupt the RING domain. We demonstrate that the variant form has an inhibitory effect on TNF-mediated NF-kappaB activation unlike the wild-type c-IAP2, which increases TNF- mediated NF-kappaB activation. These results suggest that this variant form has different activities from the wild-type and the RING domain may be involved in the regulation of TNF-induced NF-kappaB activation.

Identification of a Variant Form of Cellular Inhibitor of Apoptosis Protein (c-IAP2) That Contains a Disrupted Ring Domain

Among the members of the inhibitor of apoptosis (IAP) protein family, only Livin and survivin have been reported to have variant forms. We have found a variant form of c-IAP2 through the interaction with the X protein of HBV using the yeast two-hybrid system. In contrast to the wild-type c-IAP2, the variant form has two stretches of sequence in the RING domain that are repeated in the C-terminus that would disrupt the RING domain. We demonstrate that the variant form has an inhibitory effect on TNF-mediated NF-kappaB activation unlike the wild-type c-IAP2, which increases TNF- mediated NF-kappaB activation. These results suggest that this variant form has different activities from the wild-type and the RING domain may be involved in the regulation of TNF-induced NF-kappaB activation.