酵母双杂交技术筛选与克隆白细胞中与NS5ATP7蛋白结合的蛋白编码基因

目的 应用酵母双杂交体系寻找与丙型肝炎病毒 (HCV)非结构蛋白 5A反式激活蛋白 7(humangene 5transactivatedbynonstructuralprotein 5AofhepatitisCvirus ,NS5ATP7)相互作用的白细胞蛋白 ,以探讨SN5ATP7的生物功能。方法 应用酵母双杂交系统 3 ,构建NS5ATP7诱饵质粒 ,转化酵母AH10 9,与含人白细胞cDNA文库质粒的酵母Y187进行配合 ,于涂有X_α_gal营养缺陷型培养基 (SD/_Trp_Leu_His_Ade)上筛选生长。挑选蓝色克隆 ,提取此酵母克隆的质粒转化大肠杆菌提取质粒DNA后进行测序 ,然后进行生物信息学分析。结果 筛选出 15个与NS5ATP7特异性相互作用的克隆 ,其中包括人类RhoGDP分裂抑制剂α、人类细胞色素b5 5 8α亚单位、人类MLL(MLL)基因外显子、人类S10 0钙结合蛋白A9(钙粒蛋白B)、人类移动抑制因子相关蛋白 14变体E(S10 0A9)、人类金属硫蛋白 2A、人类染色体序列及人类cDNA序列等 ,1个是未知功能基因。结论 初步克隆了NS5ATP7与白细胞结合蛋白基因 ,根据所克隆到的基因 ,对以后研究NS5ATP7的功能有一定的提示作用 ;

The Apoptotic Effect of the Methanol Extract of <i>Polygonum cuspidatum</i>through Up-Regulation Death Receptor 5 and CHOP in HSC-2 Human Oral Cancer Cells

Polygonum cuspidatum is used as a traditional medicinal herb for the therapy of various diseases including several types of cancers. In the present study, we focused on addressing the anti-cancer activity and molecular mechanism of methanol extract of Polygonum cuspidatum (MEPC) in HSC-2 human oral cancer cells. The effect of MEPC on oral cancer cells was estimated by 3-(4,5-dimethylthiazol-20yl)-(3-carboxymethoxyphenyl)-2-(4-sulphophenyl)-2H-tetrazolium (MTS) assay, 4’-6-diamidino-2-phenylindole (DAPI) staining and Western blot analysis. MEPC inhibited the cell viability and induced apoptosis through the induction of death receptor (DR) 5. MEPC also increased the expression of C/EBP homologous protein/growth arrest and the DNA damage-inducible gene 153 (CHOP), a transcription factor induced by ER stress. Thus, we concluded that the induction of CHOP leading to DR5 up-regulation is required for the anti-cancer activity of MEPC in HSC-2 cells and MEPC may be a promising drug candidate for oral cancer.

Transplantation of human placental chorionic plate-derived mesenchymal stem cells for repair of neurological damage in neonatal hypoxic-ischemic encephalopathy

Neonatal hypoxic-ischemic encephalopathy is often associated with permanent cerebral palsy,neurosensory impairments,and cognitive deficits,and there is no effective treatment for complications related to hypoxic-ischemic encephalopathy.The therapeutic potential of human placental chorionic plate-derived mesenchymal stem cells for various diseases has been explored.However,the potential use of human placental chorionic plate-derived mesenchymal stem cells for the treatment of neonatal hypoxic-ischemic encephalopathy has not yet been investigated.In this study,we injected human placental chorionic plate-derived mesenchymal stem cells into the lateral ventricle of a neonatal hypoxic-ischemic encephalopathy rat model and observed significant improvements in both cognitive and motor function.Protein chip analysis showed that interleukin-3 expression was significantly elevated in neonatal hypoxic-ischemic encephalopathy model rats.Following transplantation of human placental chorionic plate-derived mesenchymal stem cells,interleukin-3 expression was downregulated.To further investigate the role of interleukin-3 in neonatal hypoxic-ischemic encephalopathy,we established an in vitro SH-SY5Y cell model of hypoxic-ischemic injury through oxygen-glucose deprivation and silenced interleukin-3 expression using small interfering RNA.We found that the activity and proliferation of SH-SY5Y cells subjected to oxygen-glucose deprivation were further suppressed by interleukin-3 knockdown.Furthermore,interleukin-3 knockout exacerbated neuronal damage and cognitive and motor function impairment in rat models of hypoxic-ischemic encephalopathy.The findings suggest that transplantation of hpcMSCs ameliorated behavioral impairments in a rat model of hypoxic-ischemic encephalopathy,and this effect was mediated by interleukin-3-dependent neurological function.

Non-Structural Protein 5 of Zika Virus Interacts with p53 in Human Neural Progenitor Cells and Induces p53-Mediated Apoptosis

Zika virus(ZIKV) infection could disrupt neurogenesis and cause microcephaly in neonates by targeting neural progenitor cells(NPCs). The tumor suppressor p53-mediated cell cycle arrest and apoptotic cell death have been suggested to be activated upon ZIKV infection, yet the detailed mechanism is not well understood. In the present study, we investigated the effects of ZIKV-encoded proteins in the activation of p53 signaling pathway and found that, among the ten viral proteins,the nonstructural protein 5(NS5) of ZIKV most significantly activated the transcription of p53 target genes. Using the immunoprecipitation-coupled mass spectrometry approach, we identified that ZIKV-NS5 interacted with p53 protein. The NS5-p53 interaction was further confirmed by co-immunoprecipitation and GST pull-down assays. In addition, the MTase domain of NS5 and the C-terminal domain of p53 were mapped to be responsible for the interaction between these two proteins. We further showed that ZIKV-NS5 was colocalized with p53 and increased its protein level in the nuclei and able to prolong the half-life of p53. Furthermore, lentivirus-mediated expression of ZIKV-NS5 in hNPCs led to an apparent cell death phenotype. ZIKV-NS5 promoted the cleavage of PARP1 and significantly increased the cell apoptosis of h NPCs.Taken together, these findings revealed that ZIKV-NS5 is a previously undiscovered regulator of p53-mediated apoptosis in hNPCs, which may contribute to the ZIKV-caused abnormal neurodevelopment.

Splicing factor SF3B3,a NS5-binding protein,restricts ZIKV infection by targeting GCH1

Zika virus(ZIKV),a positive-sense single-stranded RNA virus,causes congenital ZIKV syndrome in children and Guillain-Barre Syndrome(GBS)in adults.ZIKV expresses nonstructural protein 5(NS5),a large protein that is essential for viral replication.ZIKV NS5 confers the ability to evade interferon(IFN)signalling;however,the exact mechanism remains unclear.In this study,we employed affinity pull-down and liquid chromatography-tandem mass spectrometry(LC-MS/MS)analyses and found that splicing factor 3b subunit 3(SF3B3)is associated with the NS5-Flag pull-down complex through interaction with NS5.Functional assays showed that SF3B3 overexpression inhibited ZIKV replication by promoting IFN-stimulated gene(ISG)expression whereas silencing of SF3B3 inhibited expression of ISGs to promote ZIKV replication.GTP cyclohydrolase I(GCH1)is the first and ratelimiting enzyme in tetrahydrobiopterin(BH4)biosynthesis.NS5 upregulates the expression of GCH1 during ZIKV infection.And GCH1 marginally promoted ZIKV replication via the IFN pathway.Additionally,GCH1 expression is related to the regulation of SF3B3.Overexpression of the SF3B3 protein effectively reduced GCH1 protein levels,whereas SF3B3 knockdown increased its levels.These findings indicated that ZIKV NS5 binding protein SF3B3 contributed to the host immune response against ZIKV replication by modulating the expression of GCH1.