大豆GmNF-YA13互作蛋白的筛选及鉴定

大豆GmNF-YA13蛋白是一个核转录因子Y(NF-Y),在干旱和高盐响应过程中均发挥重要作用。为研究其抗旱和耐盐的作用机理,寻找GmNF-YA13的互作蛋白,构建pGBKT7-GmNF-YA13诱饵载体,采用酵母双杂交筛选大豆酵母文库,并进行X-α-gal染色验证。结果显示:酵母双杂交获得85个阳性克隆,测序分析后得到36个候选的互作蛋白。功能预测显示互作蛋白主要参与生长发育、胁迫响应、能量代谢、转录调控和信号转导等生物过程。选择GmUVR8、GmCML41、GmFbox13和GmFBA与诱饵pGBKT7-GmNF-YA13进行一对一验证,只有GmFBA能与GmNF-YA13发生相互作用,预示GmNF-YA13功能的发挥需要GmFBA的参与。该结果可为NF-YA抗逆分子网络的研究提供基础。

Analysis of Protein Interactions:Probing the Function of Proteins with Yeast Two-Hybrid System

The yeast two\|hybrid system is a molecular genetic approach for protein interaction and it is widely used to screen for proteins that interact with a protein of interest in recent years.This process includes,construction and testing of the bait plasmid,screening a plasmid library for interacting fusion protein,elimination of false positives and delection analysis of true positives.This procedure is designed to allow investigators to identify proteins and their encoding cDNAs that have a biologically significant interaction with a protein of interest.More and more studies have demonstrated that the two\|hybrid system is a powerful and sensitive technique for the identification of genes that code for proteins that interact in a biologically significant fashion with a protein of interest in higher plants.This method has been used to identify new interaction protein in many laboratories.The recently reported yeast tri\|brid system,should allow the investigation of more complex protein\|protein interactions.The aim of this review is to outline the recent progress made in protein interactions by using yeast two\|hybrid system.

甘蔗CBL-CIPK基因家族的鉴定和表达分析

【目的】甘蔗是重要的糖料作物,温度、盐碱、水分等因素是制约其生长发育的关键环境因素。类钙调磷酸酶B蛋白CBL(calcineurin B-like protein)是一类Ca^(2+)结合蛋白,通过与其特定的蛋白激酶CIPK(CBL-interacting protein kinase)作用,在Ca^(2+)信号传导通路,尤其是逆境信号传导通路中发挥重要作用。目前,甘蔗全基因组测序已完成,但其CBL-CIPK基因家族成员尚未确定,互作调控机理依然未知。本研究确定了甘蔗CBL、CIPK成员并揭示了CBL-CIPK互作关系,为研究甘蔗CBL-CIPK的互作机理提供基因资源和理论基础。【方法】以甘蔗品种‘GT58’为材料,通过RT-qPCR技术分析CBLs、CIPKs在低温、高温、NaHCO_(3)和PEG处理等4种非生物胁迫下的表达水平,利用酵母双杂交试验分析SsCBLs和SsCIPKs之间的相互作用。【结果】甘蔗全基因组中共有19个CBL基因和82个CIPK基因,分布在不同的进化分支且存在基因复制现象,基因家族成员之间理化性质差异较大,结构域与蛋白基序具有高度保守性,顺式作用元件分布多样;转录水平上,SsCBL7/SsCBL12/SsCIPK1/SsCIPK5的表达水平易受低温、高温、干旱和高盐等多种非生物胁迫的调控;蛋白水平上,SsCBL1与SsCIPK47和SsCIPK81相互作用,SsCBL8与SsCIPK47和SsCIPK81相互作用。【结论】CBL-CIPK互作网络可能在甘蔗生长发育过程中响应非生物胁迫,发挥重要作用。

冠突曲霉UBC与MAT1-2-1互作关系验证及功能研究

【目的】验证冠突曲霉泛素结合酶(UBC)与交配型蛋白(MAT1-2-1)的互作关系,对UBC基因进行功能研究,为深入解析冠突曲霉有性产孢机制提供理论参考。【方法】采用实时荧光定量PCR检测UBC基因在冠突曲霉有性发育阶段的表达水平,酵母双杂交试验验证MAT1-2-1与UBC的互作关系,利用无缝克隆方法构建pDHt/sk-hyg-UBC过表达载体,并转化冠突曲霉获得UBC过表达菌株,对过表达菌株进行表达量检测、形态学观察及氧和盐胁迫的耐受性测定。【结果】PCR克隆获得UBC基因的编码区(CDS)序列,长度为474 bp,编码157个氨基酸残基,相对分子质量为39587.24 Da,理论等电点为5.16,为疏水的不稳定蛋白,含跨膜结构域,定位于细胞核,属于UBCc超家族成员。有性发育阶段(闭囊壳形成期和子囊孢子大量形成期)UBC基因的相对表达量显著高于营养菌丝体阶段(P<0.05,下同)。自激活检测结果显示,UBC无自激活作用;酵母双杂交验证结果显示,UBC与MAT1-2-1存在互作关系。通过构建过表达载体pDHt/sk-hyg-UBC成功获得UBC过表达菌株(OE::UBC)。与野生型菌株相比,UBC和MAT1-2-1基因在UBC过表达菌株的相对表达量均显著升高。UBC过表达菌株与野生型菌株在MYA、MYA+5%NaCl和MYA+17%NaCl固体培养基上的菌落形态无明显差异。过表达菌株能分别在含18 mmol/L过氧化氢和25%NaCl的培养基中生长,而野生型菌株不能生长,说明UBC基因的过表达提高冠突曲霉对氧胁迫和盐胁迫的耐受性。【结论】UBC基因可能与冠突曲霉的有性发育相关,且与MAT1-2-1基因存在共表达特征。由于UBC与MAT1-2-1存在互作关系,且UBC基因的过表达可明显增强冠突曲霉的抗氧化和抗盐能力,故推测UBC通过与MAT1-2-1发生互作共同参与冠突曲霉的氧胁迫和盐胁迫应答过程。

Screening for Novel Binding Proteins Interacting with Human Papillomavirus Type 18 E6 Oncogene in the Hela cDNA Library by Yeast Two-Hybrid System

To screen for novel binding proteins interacting with high-risk HPV 18 E6 oncogene, the strain AH 109 was transformed with pGBKT7-HPV 18 E6 plasmid, and subsequent transference was utilized to screen for interacting proteins with HPV 18 E6 in human Hela cDNA library. HPV 18 E6 mRNA was expressed in yeast and there was no self-activation and toxicity in AH109. Seven proteins that interacted with HPV18 E6, including transmembrane protein 87B, phosphonoformate immuno-associated protein 5, vimentin, KM-HN-1 protein, dedicator of cytokinesis 7, vaccinia related kinase 2 and a hypothetical protein, were identified. It was suggested that yeast two-hybrid system is an efficient for screening interacting proteins. The high-risk HPV 18 E6 oncogene may interact with the proteins, which may be associated with signal transduction and transcriptional control, epithelial cell invasion and migration, as well as humoral and cellular immune etc. This investigation provides functional clues for further exploration of potential oncogenesis targets for cancer biotherapy.

Shared and discrete interacting partners of ELL1 and ELL2 by yeast two-hybrid assay

ELL2 (eleven-nineteen lysine-rich leukemia transcription elongation factor), a component of a larger complex with pTEFb (cyclin T and CDK9) and AF4, is up-regulated in plasma cells where it influences mRNA processing by increasing exon skipping and enhancing proximal poly (A) site use. ELL2 is needed to produce the secretory-specific Ig heavy chain mRNA while ELL1 mRNA does not change in abundance with B cell stages. To investigate the potential interactions of other proteins with the ELL1 and ELL2 proteins, we preformed yeast two-hybrid studies. HSP40 and Testin were found to bind to ELL2 in its amino-terminal half. PCNA binds to ELL2 in a region encompassing amino acids 186 - 344. The potent transcription factors HIF1 α and ZNF622 interact with both ELL1 and 2 in the central, proline rich region. Meanwhile, BBS2 and ING3 interact with ELL1 but not ELL2 in this central proline-rich region. Many of the ELL-interacting-proteins uncovered in the two-hybrid screen are tumour suppressors that may work through the ELL: pTEFb complex to suppress or activate sets of genes in plasma cells.

Screening of hepatocyte proteins binding to NS5ABP37 protein by yeast-two hybrid system

Objective To investigate the biological function of NS5ABP37 and to look for proteins interacting with NS5ABP37 protein in hepatocytes.Methods We constructed bait plasmid expressing NS5ABP37 protein of hepatitis C virus(HCV)by cloning the gene of NS5ABP37 protein into pGBKT7,then the recombinant plasmid DNA was transformed into yeast AH109(α type).The transformed yeast AH109 was mated with yeast Y187(α type)containing liver cDNA library plasmid in 2×YPDA medium.Diploid yeast was plated on synthetic dropout nutrient medium(SD/-Trp-Leu-His-Ade)containing X-α-gal for selection and screening.After extracting and sequencing of plasmids from positive(blue)colonies,we made a sequence analysis by bioinformatics.Results We screened twenty-five proteins binding to NS5ABP37,including Homo sapiens cyclin I(CCNI)gene,Homo sapiens matrix metallopeptidase 25(MMP25)and Homo sapiens talin 1.Conclusion The yeast-two hybrid system is an effective method for identifying hepatocyte proteins interacting with NS5ABP37 of HCV.And the biological function of NS5ABP37 may be associated with glycometabolism,lipid metabolism and apoptosis.

MicroRNA-502-3p regulates GABAergic synapse function in hippocampal neurons

Gamma-aminobutyric acid(GABA)ergic neurons,the most abundant inhibitory neurons in the human brain,have been found to be reduced in many neurological disorders,including Alzheimer's disease and Alzheimer's disease-related dementia.Our previous study identified the upregulation of microRNA-502-3p(miR-502-3p)and downregulation of GABA type A receptor subunitα-1 in Alzheimer's disease synapses.This study investigated a new molecular relationship between miR-502-3p and GABAergic synapse function.In vitro studies were perfo rmed using the mouse hippocampal neuronal cell line HT22 and miR-502-3p agomiRs and antagomiRs.In silico analysis identified multiple binding sites of miR-502-3p at GABA type A receptor subunitα-1 mRNA.Luciferase assay confirmed that miR-502-3p targets the GABA type A receptor subunitα-1 gene and suppresses the luciferase activity.Furthermore,quantitative reve rse transcription-polymerase chain reaction,miRNA in situ hybridization,immunoblotting,and immunostaining analysis confirmed that overexpression of miR-502-3p reduced the GABA type A receptor subunitα-1 level,while suppression of miR-502-3p increased the level of GABA type A receptor subunitα-1 protein.Notably,as a result of the overexpression of miR-502-3p,cell viability was found to be reduced,and the population of necrotic cells was found to be increased.The whole cell patch-clamp analysis of human-GABA receptor A-α1/β3/γ2L human embryonic kidney(HEK)recombinant cell line also showed that overexpression of miR-502-3p reduced the GABA current and overall GABA function,suggesting a negative correlation between miR-502-3p levels and GABAergic synapse function.Additionally,the levels of proteins associated with Alzheimer s disease were high with miR-502-3p overexpression and reduced with miR-502-3p suppression.The present study provides insight into the molecular mechanism of regulation of GABAergic synapses by miR-502-3p.We propose that micro-RNA,in particular miR-502-3p,could be a potential therapeutic to rget to modulate GABAergic synapse function in neurological disorders,including Alzheimer's disease and Alzheimer's diseaserelated dementia.

Construction of a Three-frame Yeast Two-hybrid cDNA Library of Fusarium oxysporum

A specialized test of two-hybrid library type three-frame cDNA yeast for Muskmelon Fusarium oxysporum using the switching mechanism at the 5'end of RNA template(SMART)technology was constructed to screen for interaction protein genes for wilt disease and to further research the molecular mechanisms of Fusarium oxysporum pathogenesis to explain the interactions between plant and pathogen.A 500-bp cDNA was purified and extracted using SMART and LD-PCR technology to synthesize ds cDNA and was then homogenized and purified to remove the fragments.After processing,the ds cDNA was connected to three types of reading frame pGADT7-SfiI carriers,and the three connection products in E.coli Electrocell were used to build the primary cDNA library.The titer of three ORF cDNA primary library storage capacities was 2.6×10^6,1.8×10^6 and 3×10^6 cfu;the PCR identification of the ORF 1 and 2 gene recombination rate was 94%,the ORF 3 gene recombination rate was 100%,and the insert length distribution was 0.5-4.0 kb as a single band.To reach the quality requirements for library construction,three kinds of reading frame cDNA primary libraries were mixed and amplified,and the plasmid was transformed into the Y187 yeast strain.The titer of the Y187 yeast library was determined to be 3.5×107 cfu?mL-1,and the base of the yeast library was approximately 1 600 000 cfu.The results showed that the construction of muskmelon Fusarium-specific two-hybrid library type three-frame cDNA yeast had a higher reservoir capacity and recombination rate and met the yeast two-hybrid screening requirements.

Screening proteins that interact with mutant superoxide dismutase 1 from familial amyotrophic lateral sclerosis using a yeast two-hybrid system

The present study screened a human fetal brain cDNA library to find the proteins that interact with mutant superoxide dismutase 1 （SOD1） using a yeast two-hybrid system. Using BLAST software, 15 real proteins which interacted with mutant SOD1 were obtained, including 8 known proteins （protein tyrosine-phosphatase non-receptor type 2, TBCl D4, protein kinase family, splicing factor, arginine/serine-rich 2, SRC protein tyrosine kinase Fyn, β-sarcoglycan; glycine receptor a2, microtubule associated protein/microtubule affinity-regulating kinase 1, ferritin H chain）, and 7 unknown proteins. Results demonstrated interaction of mutant SOD1 with microtubule associated protein/microtubule affinity-regulating kinase 1 and β-sarcoglycan.

Construction and Identification of a Yeast Two-Hybrid Bait Vector and Its Effect on the Growth of Yeast Cells and the Self-Activating Function of Reporter Genes for Screening of HPV18 E6-Interacting Protein

By using a yeast two-hybrid system,a yeast two-hybrid bait vector was constructed and identified for screening of the HPV18 E6-interacting proteins,and its effects on the growth of yeast cells and the activation of reporter genes were investigated.Total mRNA extracted from Hela cells was reversely transcribed into cDNA.Fragment of HPV18 E6 cDNA was amplified using RT-PCR and directly ligated to the pGBKT7 vector.The recombinant plasmid was confirmed by restriction endonuclease analysis and DNA sequencing.Th...

Screening of Host Proteins Interacting with PorcineEpidemic Diarrhea Virus (PEDV) N Protein by YeastTwo-hybrid System

[Objective] The paper was to obtain host proteins interacting with porcine epidemic diarrhea virus （PEDV） N protein. [Method] The re-combinant vector pGBKT7-N of PEDV N gene was constructed and used as the bait plasmid to screen the proteins interacting with N protein ofPEDV from the cDNA library of porcine alveolar macrophage （PAM） by yeast two-hybrid method. [Result] There was no toxicity and self activationof bait protein in yeast hybridization system, and six proteins （FTH1, LGALS3, CORO1C, SNRPG, KRTAP5-3, ZNF598） interacting with N proteinwere indentified. It was confirmed that LGALS3 and SNRPG had specific interaction with N protein by return experiment and co-immunoprecipitation（CoIP） test. [Conclusion] The study lays a foundation for further studying the function of PEDV N protein and the pathogenic mechanism of PEDV.

Yeast One-hybrid System Used to Identify the Binding Proteins for Rat Glutathione S-transferase P Enhancer I

Objective To detect the trans-factors specifically binding to the strong enhancerelement (GPEI) in the upstream of rat glutathione S-transferase P (GST-P) gene. MethodsYeast one-hybrid system was used to screen rat lung MATCHMAKER cDNA library toidentify potential trans-factors that can interact with core sequence of GPEI(cGPEI).Electrophoresis mobility shift assay (EMSA) was used to analyze the binding of trans-factors to cGPEI. Results cDNA fragments coding for the C-terminal part of thetranscription factor c-Jun and rat adenine nucleotide translocator (ANT) were isolated. Thebinding of c-Jun and ANT to GPEI core sequence were confirmed. Conclusions Rat c-juntranscriptional factor and ANT may interact with cGPEI. They could play an important rolein the induced expression of GST-P gene.

In Search of Regulators of <i>LeSPL-CNR</i>by South-Western Blotting and Yeast One-Hybrid Library Screening System

LeSPL-CNR is a crucial transcription factor for fruit ripening of Solanum lycopersicum. The cnr (colorless non-ripening) epimutation resulted from hypermethylation in a 286 bp region of LeSPL-CNR promoter inhibits normal fruit ripening. In present study, potential regulators of LeSPL-CNR, which could bind to the specific 286 bp region, were screened via south-western blotting and yeast one-hybrid (Y1H) library screening system. Results indicated that a total of 13 and 19 candidate proteins were acquired respectively, and both ribulose-1,5-bisphosphate carboxylase/oxygenase and 40S ribosomal protein were identified by two methods. These would provide some information for revealing roles of DNA methylation and the regulatory mechanism for LeSPL-CNR.

甘蓝型油菜-核盘菌酵母双杂交cDNA文库构建及BnJar1互作蛋白筛选

油菜与核盘菌相互作用的过程中,JA(茉莉酸)合成相关基因表达量升高,但是JA信号传递却受到了抑制,推测核盘菌分泌的效应蛋白可能直接或间接作用于JAR1蛋白,使其活性降低,从而抑制依赖JA途径的油菜防御系统。前期通过转录组测序获得了差异表达基因BnJar1全长序列,为进一步揭示BnJar1基因参与油菜-核盘菌相互作用过程的机理,本研究对BnJAR1蛋白进行生物信息学分析和预测,构建了核盘菌-油菜互作表达基因酵母文库,并以BnJar1作为诱饵蛋白对文库进行酵母双杂交筛选,获得了5个来自油菜的互作蛋白:丙二烯氧化物环化酶2(BnAOC2)、COP9信号复合物(BnCOP9)、4a-羟基四氢生物蝶呤脱水酶(BnDcoH)、腈水解酶2(BnNIT2)和茎特异性蛋白(BnTSJT1);2个来自核盘菌的互作蛋白:MFS结构域蛋白(SsMFS)和Rho3 GTP酶(SsRho3)。相关结果为研究油菜-核盘菌的相互作用,挖掘致病或抗病相关基因,进一步解析其机理奠定了基础。

Hybrid Ⅲ-50th-RS假人上腹部冲击试验探究

列车碰撞事故中,人体腹部是一个比较容易受到严重损伤的部位之一,为开发设计出适用于列车碰撞试验所用假人——Hybrid Ⅲ-50th-RS假人的腹部,开展针对假人上腹部的冲击试验探究。Hybrid Ⅲ-50th-RS假人上腹部的研究主要是参考THOR-NT假人上腹部冲击试验标准,结合国外Hybrid Ⅲ-50th-RS上腹部标定方法进行的试验探索。利用假人生产制作的常用材料,研究假人上腹部多层泡沫材料的组合方案、假人坐姿、压力分配板与腹袋是否连接、是否穿胸部皮肤以及假人上腹部的结构等对假人上腹部标定的影响及其响应特性。通过对试验数据进行分析,总结Hybrid Ⅲ-50th-RS假人上腹部冲击标定的影响因素及试验规律。根据所参考的THOR-NT假人上腹部冲击试验生物力学响应标准,确定符合试验要求的Hybrid Ⅲ-50th-RS假人上腹部的材料组合及其结构方案。研究结果表明:进行Hybrid Ⅲ-50th-RS假人上腹部冲击试验时,假人配有胸部皮肤,保持上腹部水平,压力分配板与腹袋保持连接更符合试验要求。采用后层2块丁晴橡胶板+中层三元乙丙泡沫+前层聚氨酯泡沫的“四层式”腹部结构和“前软中软”的材料搭配方案,具有较好的生物力学响应特性,适合用做列车碰撞试验假人上腹部。

大豆GmWRKY52生物信息学分析及与GmNF-YA13互作研究

WRKY转录因子在植物生长发育及逆境调控过程发挥着重要作用。前期通过酵母双杂交筛选干旱处理后的大豆cDNA文库时发现GmWRKY52(NP_001237726.2)可能与GmNF-YA13蛋白存在互作,为明确二者是否存在互作,本研究克隆GmWRKY52基因并进行生物信息学分析,利用酵母双杂交系统鉴定GmWRKY52和GmNF-YA13之间的互作关系。结果显示:GmWRKY52基因全长1 163 bp,编码1个由265个氨基酸组成的蛋白质,多序列比对和系统发育树分析结果说明GmWRKY52基因与野生大豆GsWRKY69(XP_028186817.1)亲缘关系较近。酵母双杂交结果表明GmWRKY52和GmNF-YA13蛋白不存在相互作用。研究结果说明GmWRKY52与GmNF-YA13蛋白在酵母细胞内并不发生互作。

小麦硝酸盐转运蛋白TaNRT1.1-1A转录活性检测及互作蛋白筛选

为了进一步解析小麦硝酸盐转运蛋白TaNRT1.1-1A的调控机制,本研究对其进行了自激活性检测。利用已构建好的小麦酵母cDNA文库,以TaNRT1.1-1A为诱饵,通过酵母双杂交技术筛选其互作蛋白,回转试验进一步验证其互作关系。结果表明,TaNRT1.1-1A无自激活活性,酵母双杂技术筛选小麦cDNA文库,共获得2个候选互作蛋白,候选蛋白Sdr I-like主要参与植物病害有关的应答响应。Sdr I-like的回转验证结果表明,该蛋白可能与TaNRT1.1-1A存在互作关系。该结果可为进一步研究TaNRT1.1-1A调控小麦硝酸盐吸收有关的分子机制奠定基础。

Probiotic yeasts: Anti-inflammatory potential of various non-pathogenic strains in experimental colitis in mice

AIM: To evaluate the in vitro immunomodulation capacity of various non-pathogenic yeast strains and to investigate the ability of some of these food grade yeasts to prevent experimental colitis in mice.METHODS: In vitro immunomodulation was assessed by measuring cytokines [interleukin (IL)-12p70,IL-10,tumor necrosis factor and interferon γ] released by human peripheral blood mononuclear cells after 24 h stimulation with 6 live yeast strains (Saccharomyces ssp.) and with bacterial reference strains.A murine model of acute 2-4-6-trinitrobenzene sulfonic acid (TNBS)-colitis was next used to evaluate the distinct prophylactic protective capacities of three yeast strains compared with the performance of prednisolone treatment.RESULTS: The six yeast strains all showed similar non-discriminating anti-inflammatory potential when tested on immunocompetent cells in vitro .However,although they exhibited similar colonization patterns in vivo ,some yeast strains showed significant anti-inflammatory activities in the TNBS-induced colitis model,whereas others had weaker or no preventive effect at all,as evidenced by colitis markers (body-weight loss,macroscopic and histological scores,myeloperoxidase activities and blood inflammatory markers).CONCLUSION: A careful selection of strains is required among the biodiversity of yeasts for specific clinical studies,including applications in inflammatory bowel disease and other therapeutic uses.

Chromosome analysis of esophageal squamous cell carcinoma cell line KYSE 410-4 by repetitive multicolor fluorescence in situ hybridization

Chromosome aberrations are distinctive features of human malignant tumors. Analysis of chromosomal changes can illuminate the molecular mechanisms underlying the development and progression of cancer. To establish the technique of multicolor fluorescence in situ hybridization （M-FISH） for identifying chromosome aberrations in esophageal carcinoma cell line KYSE 410-4, four pools of 6-color whole-chromosome painting probes have been designed and hybridized on the same metaphase spread by four rounds of repetitive FISH. Repetitive 6-color M-FISH was successfully established and the cytogenetic abnormalities in KYSE 410-4 cells were characterized. Chromosome gains occurred at 2q, 3, 8, 17p, and X. An isochromosome 3q was visualized in the cell line, which might be one intermediate mechanism leading to 3p losses and/or 3q gains. Furthermore, 16 structural arrangements were detected, including four derivative chromosomes. The rearrangement of the centromeric regions accounted for approximately 44% of all rearrangements. The results added a more complete and accurate information of the genetic alterations to the classical cytogenetic description of KYSE 410-4 and provided a detailed cytogenetic background data for appropriate use of the cell line. The established 6-color M-FISH was useful for analyzing chromosomes in the whole genome of human tumors.