共查询到20条相似文献,搜索用时 203 毫秒
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目的 研究外源性硫化氢(H2S)通过丝裂原活化细胞外信号调节蛋白激酶(MEK)/细胞外信号调节激酶(ERK)信号通路对早期糖尿病肾脏疾病(DN)大鼠的保护作用。方法 随机选取SPF级健康雄性SD大鼠24只腹腔一次性注射1%链尿佐菌素(STZ)60 mg/kg制作DN模型,余下10只(正常对照组)腹腔一次性注射等量的柠檬酸缓冲液。3周后DN造模成功,再将24只DN大鼠随机分为DN组和DN+硫氢化钠(NaHS)组,每组各12只。DN+NaHS组予腹腔注射NaHS溶液56μmol·kg-1·d-1,正常对照组和DN组予等量生理盐水腹腔注射,3组大鼠均连续注射12周。检测各组血清肌酐(SCr)、尿素氮(BUN)及24小时尿蛋白(24h Upro)水平,观察其肾脏组织病理变化。采用Katafuchi评分评估大鼠肾脏病变(包括肾小球、肾小管及肾血管)。采用免疫组化法检测ERK1/2、MEK1和MEK2蛋白阳性区域面积百分比。结果 DN组大鼠SCr、BUN及24h Upro水平、肾脏组织Katafuchi评分、MEK1、MEK2及ER... 相似文献
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细胞外调节蛋白激酶通路对胃癌细胞化疗效果的影响 总被引:1,自引:0,他引:1
目的:观察细胞外调节蛋白激酶(extraeelluar regulated protein kinase,ERK)信号通路对胃癌细胞化疗效果的影响并探讨其机制.方法:足叶乙甙作用于胃癌SGC7901和BGC823细胞,采用MTT比色法检测细胞的生存率,采用流式细胞仪和Hoechst33258荧光染色检测细胞周期分布和凋亡,Western杂交法检测ERK1/2的磷酸化以及c-Myc和P53蛋白表达水平.同时采用PD98059抑制ERK信号通路后观察足叶乙甙对细胞增殖、凋亡、c-Myc和P53表达的影响.结果:足叶乙甙呈时间-剂量依赖性抑制SGC7901和BGC823细胞的生长并明显诱导细胞的凋亡,同时上调ERK1/2的活性(磷酸化水平),并增强c-Myc和P53的表达,与对照组比较,足叶乙甙组凋亡率明显增高(19.48%±1.57% vs 5.67%±0.81%.17.38%±1.49% vs4.97%±0.73%,均P<0.01),PD98059可明显增强足叶乙甙的细胞生长抑制作用并提高细胞的凋亡水平,与足叶乙甙组比较,足叶乙甙组 PD98059组凋亡率(34.35%±2.84%,32.11%±3.25%)明显增加(P<0.01);同时上调足叶乙甙诱导的P53表达,并抑制c-Myc表达的上升趋势.结论:足叶乙甙可活化胃癌细胞ERK信号通路而影响胃癌细胞的化疗效果,其机制可能是通过抑制P53并上调c-Myc的表达,从而抑制细胞的凋亡实现. 相似文献
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细胞外信号调节激酶(ERK)通路是一种重要的细胞内信号转导通路,ERK是该通路的关键酶,气道平滑肌中有ERK1/2分布,ERK参与气道平滑肌表型改变、内膜下迁移、细胞的增殖与凋亡等多种功能。 相似文献
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目的观察细胞外信号调节激酶1/2(ERK1/2)在血管紧张素Ⅱ诱导的内皮细胞中不同时点的表达变化,为阐明血管内皮细胞凋亡对动脉粥样硬化的诊治具有重要意义。方法制备血管紧张素ⅡRPMI1640培养液(10-6mol/L)培养人脐静脉内皮细胞,采用四甲基偶氮唑蓝比色法测定内皮细胞存活率,通过AnnexinV-FITC/PI双染流式细胞仪检测细胞凋亡率、Hochest33258荧光染色观察凋亡细胞形态学的变化,利用RT-PCR法分析凋亡调控基因Bcl-2、Bax mRNA表达变化,Western-Blot测定磷酸化ERK1/2水平。结果血管紧张素Ⅱ诱导内皮细胞的凋亡率明显高于对照组(P<0.01),与对照组相比,Bcl-2 mRNA表达呈持续性降低;Bcl-2/Bax比值下降,ERK1/2磷酸化水平于12 h明显增加,18 h达到高峰(P<0.01),24 h下降至稳定,总ERK1/2蛋白水平无明显变化。结论 ERK1/2信号转导途径参与血管紧张素Ⅱ诱导内皮细胞的凋亡发生、发展过程,并可能通过调控内皮细胞Bcl-2/Bax比值来实现。 相似文献
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目的研究3种化疗药物抑制肝癌SMMC-7721细胞增殖、促进细胞凋亡过程中端粒酶活性及细胞外调节蛋白激酶(ERK)磷酸化蛋白表达水平的变化,探讨端粒酶与ERK在肝癌细胞凋亡过程中的调节作用及相互之间的关系. 方法用MTT法、流式细胞术检测法、端粒重复序列扩增法(TRAP法)、生物发光分析法及western blot检测法. 结果 3种化疗药物使肝癌细胞增殖受抑并诱发凋亡(细胞凋亡率分别为21.12%、28.83%、12.30%)的同时,端粒酶活性也有不同程度减低(抑制率分别为0.28%±0.08%,0.25%±0.16%,0.24%±0.11%);处于活化状态的磷酸化ERK1/2蛋白表达水平下降. 结论 ERK通路可能是化疗药物下调端粒酶活性,进而促进细胞凋亡的机制之一. 相似文献
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目的 明确在乙型肝炎病毒X基因(HBx)对原癌蛋白质(c-met)基因启动子区的调控中所涉及的信号传导通路及其在肝癌侵袭和转移中的作用.方法 用Western blot比较可能涉及的信号通路特异性阻断剂对HBx调控c-met表达的影响,分析在该调控过程中所涉及的信号通路.体外侵袭试验验证信号传导通路在HBx调控c-met表达中的作用.对数据进行析因设计的方差分析.结果 HBx引起c-met表达水平的增加,细胞外调节蛋白激酶信号通路抑制剂U0126能够降低该作用,而p38MAPK信号通路抑制剂SB203580、PI-3K信号通路抑制剂wortmanin则未显示出该作用.体外细胞侵袭试验也证实了U0126能够降低HBx引起的HepG2细胞的强侵袭性[(74.3±6.2)个与(34.6±5.2)个,F=113.45,P<0.01].结论 HBx引起肝癌细胞的侵袭转移可能与其通过细胞外调节蛋白激酶信号通路对c-met基因启动子区(-183 bp~-100 bp)的调控有关. 相似文献
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目的探讨细胞外调节蛋白激酶(ERK)1/2信号转导通路在βTC-6细胞葡萄糖刺激胰岛素分泌(GSIS)反应中的作用。方法采用不同浓度葡萄糖刺激βTC-6细胞,放射免疫法检测细胞上清液中胰岛素浓度,Western blot检测细胞裂解物ERK1/2磷酸化水平。采用MEK抑制剂PD98059处理βTC-6细胞,放射免疫法检测葡萄糖刺激后上清液中胰岛素浓度,Western blot检测葡萄糖刺激后ERK1/2磷酸化水平。结果βTC-6细胞在1.38mmol/L葡萄糖刺激时,胰岛素分泌和ERK1/2磷酸化水平达高峰。PD98059可抑制葡萄糖刺激下ERK1/2磷酸化及胰岛素分泌,作用与剂量呈正相关。结论ERK1/2信号转导通路可能在βTC-6细胞GSIS中发挥作用。 相似文献
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细胞外信号调节激酶信号通路对乙醛刺激的大鼠肝星状细胞周期的影响 总被引:3,自引:1,他引:3
目的 观察特异性丝裂原细胞外信号反应激酶1(MEK 1)阻断剂(PD98059)对乙醛刺激的大鼠肝星状细胞(HSC)增殖及细胞周期的影响,并探讨其作用机制。 方法 用不同浓度的PD98059对乙醛刺激的HSC进行处理;以四甲基偶氮唑蓝法检测细胞增殖,流式细胞仪检测细胞周期,逆转录聚合酶链反应方法检测HSC内细胞周期蛋白-D1(Cyclin D1)mRNA和细胞周期蛋白依赖性激酶(CDK4)mRNA的表达。 结果 20、50、100μmol/L的PD98059均能显著且剂量依赖性地抑制乙醛刺激的HSC增殖,3组A值分别为0.109±0.020、0.081±0.010、0.056±0.020,与乙醛组A值0.146±0.030相比较,F=31.385,P<0.05;20、50、100 μmol/L的PD98059可显著抑制乙醛刺激的HSC由G1期进入S期,G0/G1期细胞百分比逐渐升高,3组G0/G1期细胞百分比分别为(61.9±6.3)%、(64.1±3.3)%、(70.9±4.8)%,与乙醛组(55.2±4.4)%相比较,F=16.402,P<0.05;50、100μmol/L的PD98059能显著抑制乙醛刺激的HSC内Cylin D1 mRNA表达,2组平均光强度比值分别为0.56±0.04,0.46±0.03,与乙醛组0.65±0.07相比较,F=68.758,P<0.05;50、100μmol/L的PD98059能显著抑制乙醛刺激的HSC内CDK4 mRNA表达,2组平均光强度比值分别为0.39±0.07,0.33±0.05,与乙醛组0.50±0.06相比较,F=29.406,P<0.05。 结 相似文献
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目的 探讨蛋白激酶C(PKC)-胞外信号调节激酶(ERK)1/2信号通路在尼古丁诱导人脐静脉内皮细胞(HUVECs)表达纤维溶解酶原激活物抑制物-1(PAI-1)中的作用.方法 体外培养HUVECs,采用不同实验条件尼古丁进行干预,ELISA法测定细胞上清液中PAI-1的浓度,观察尼古丁作用的最佳浓度和时间.进一步分别用PKC的抑制剂星型胞菌素staurosporine (STS)和ERK的抑制剂PD98059干预HUVECs,观察PKC或ERK被阻断后对尼古丁诱导的HUVECs 表达PAI-1的影响,ELISA测定各组细胞上清液中PAI-1蛋白的表达水平,RT-PCR检测各组细胞PAI-1 mRNA的表达.结果 100 μmol/L尼古丁组PAI-1蛋白水平[(22.6 ± 1.1)μg/L]明显高于对照组[(14.2± 2.8)μg/L,q=5.64,P<0.05];以100 μmol/L 尼古丁分别与HUVECs孵育0、4、6、8、12及24 h,各组PAI-1蛋白表达呈时间依赖性升高,并在12 h达到高峰(F=32.063,P<0.05);尼古丁组PAI-1 mRNA及蛋白含量[(1.32±0.20),(21.08±0.83)μg/L]明显高于对照组[(0.73±0.10),(13.39± 0.93)μg/L,q=8.43、11.97,均P<0.05];尼古丁+STS组PAI-1 mRNA及蛋白含量[(1.07±0.10),(16.19±2.15)μg/L]较尼古丁组降低(q=5.61、7.61,均P<0.05),但仍高于对照组(q=7.84、4.36,均P<0.05);尼古丁+ PD98059组PAI-1 mRNA及蛋白表达[(1.12±0.11),(17.52±1.72)μg/L]低于尼古丁组(q=4.68、5.54,均P<0.05),仍高于对照组(q=8.77、6.43,均P<0.05).结论 PKC-ERK1/2信号通路在尼古丁诱导的血管内皮细胞PAI-1表达上调中发挥一定作用.Abstract: Objective To explore the role of protein kinase C (PKC)- extracellular signal-regulated kinase (ERK)1/2 signal pathway in the process of plasminogen activator inhibitor-1(PAI-1) protein and mRNA expression in cultured human umbilical vein endothelial cells(HUVECs) induced by nicotine. Methods HUVECs were cultured to examine the effect of nicotine on the expression of secreting PAI-1 in HUVECs on different experimental conditions. The expression of PAI-1 protein was measured by ELISA. PKC inhibitor staurosporine (STS)and ERK1/2 inhibitor PD98059 were used to detect PKC or ERK1/2 function on the expression of PAI-1 in HUVECs induced by nicotine. The PAI-1 mRNA expression was determined by RT-PCR. Results The expression level of PAI-1 protein in 100 μmol/L nicotine treated group [(22.6±1.1) μg/L] increased significantly compared to the control group [(14.2±2.8) μg/L; q=5.64,P<0.05]. After stimulation with 100 μmol/L nicotine for 0,4,6,8,12 and 24 h, the levels of PAI-1 protein increased over time and reached the peak at 12 h (F=32.063,P<0.05).The PAI-1 mRNA and protein expression in nicotine treated group [(1.32±0.20), (21.08 ± 0.83) μg/L] increased significantly compared to the control group [(0.73±0.10), (13.39±0.93) μg/L; q=8.43,11.97,all P<0.05].Compared with nicotine treated group , the PAI-1 mRNA and protein expression in nicotine and STS treated group [(1.07±0.10),(16.19±2.15) μg/L] decreased significantly(q=5.61,7.61, all P<0.05), but still higher than the control group (q=7.84,4.36, all P<0.05). In nicotine and PD98059 treated group, the PAI-1 mRNA and protein expression [(1.12±0.11),(17.52±1.72) μg/L] decreased significantly compared to the nicotine treated group(q= 4.68,5.54, all P<0.05), still higher than the control group (q=8.77,6.43, all P<0.05). Conclusion PKC-ERK1/2 signal pathway may play a partial role in the up-regulation of PAI-1 induced by nicotine in HUVECs. 相似文献
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C-type lectin-like oxidized low-density lipoprotein (Ox-LDL) receptor-1 (Lox-1) belongs to the same family as natural killer cell receptors Ly49A and CD94 and functionally undergoes dimerization. Although Lys262 and Lys263 in the C terminus of bovine (b)Lox-1 play an important role in the uptake of Ox-LDL, mutation of these residues has not been suggested to be a potential source of the dominant-negative property. We hypothesize that dominant-negative human (h)Lox-1 forms a heterodimer with Lox-1-wild-type (WT) and blocks Lox-1-WT-induced cell signaling. Based on the use of molecular imaging techniques with laser scanning confocal microscopy and immunoprecipitation in an hLox-1-expressing Chinese hamster ovary cell system, homodimerization of hLox-1-WT was localized in the cell membrane, and Ox-LDL activated extracellular signal regulated kinase (ERK)1/2 without the translocation of hLox-1-WT. Lys266 and Lys267 of hLox-1, corresponding with Lys262 and Lys263 of bLox-1, were mutated (hLox1-K266A/K267A), and the mutant receptor inhibited hLox-1-WT-induced thymidine incorporation and ERK1/2 activation. Although Ox-LDL binds to the dominant-negative mutant receptor and is taken up by cytoplasm, ERK1/2 activation was blocked by heterodimerization with the mutant receptor and hLox-1-WT in the cell membrane. In addition, in human coronary artery smooth muscle cells, which express hLox-1-WT, we confirmed that the activation of ERK1/2 and [3H]-thymidine incorporation was caused by the addition of Ox-LDL, and these actions were blocked by hLox1-K266A/K267A. In conclusion, the present findings constitute the first evidence that strategies aimed at blocking cell-proliferative pathways at the receptor level could be useful for impairing Lox-1-induced cell proliferation. 相似文献
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OBJECTIVE: Vascular smooth muscle cell (VSMC) differentiation, growth and survival, key events in the development of cardiovascular diseases, are under the control of signaling enzymes including extracellular signal regulated kinase 1/2 (ERK 1/2), Akt and epidermal growth factor receptor (EGFR) activation. EGFR trans-activation is known to mediate thrombin- or angiotensin II (AII)-stimulated ERK 1/2 activation. However, our laboratory has demonstrated, in thrombin-stimulated VSMC, that the prevention of intracellular Ca2+ elevation ([Ca2+]i) by BAPTA-AM pretreatment unveiled EGFR-independent ERK 1/2 activation. Since calcium channel blockers (CCBs) also impair agonist-induced [Ca2+]i elevation, we investigated whether EGFR-independent ERK 1/2 activation could occur in VSMCs treated by CCBs such as amlodipine, isradipine and verapamil, and examined the possible role of Akt. METHODS: Cultured VSMCs were pretreated or not with CCBs and with various inhibitors of the signaling pathways under study, prior to stimulation by thrombin or AII, and the phosphorylation/activation status of EGFR, Akt and ERK 1/2 was determined by Western blotting using phospho-specific antibodies. RESULTS AND CONCLUSION: Unlike BAPTA, CCBs did not impair stimulus-induced EGFR trans-activation, hence ERK1/2 phosphorylation. However, when EGFR kinase was inhibited, CCBs and BAPTA dose-dependently protected stimulus-induced ERK1/2 phosphorylation. The effect of amlodipine could not be mimicked by its R+ enantiomer, which is devoid of CCB activity, suggesting that the effects of CCBs were accounted for by their L-type Ca2+ channel-blocking property. Altogether, our results indicated that in G-protein-coupled receptor (GPCR)-stimulated VSMCs, the prevention of [Ca2+]i elevation by CCBs unmasked an EGFR kinase-independent phosphorylation of ERK 1/2. Since EGFR kinase inhibitors are supposed to be efficient in the treatment of some cancers, such a mechanism might be clinically relevant in hypertensive patients with cancer. 相似文献
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《中国老年学杂志》2019,(16)
目的探讨丝胶蛋白对2型糖尿病模型大鼠肾脏细胞外信号调节激酶(ERK)表达的影响。方法 36只健康成年雄性SD大鼠随机均分为正常对照组、模型组和丝胶蛋白组。腹腔注射小剂量链脲佐菌素建立2型糖尿病大鼠模型;成功建模后,丝胶蛋白组大鼠给予丝胶[2.4 g/(kg·d)]灌胃用药35 d。检测各组大鼠血糖、24 h尿蛋白、血尿素氮和血肌酐含量;分别采用免疫印迹法和逆转录PCR法检测肾脏ERK蛋白和mRNA的表达情况。结果与正常对照组比较,模型组空腹血糖、24 h尿蛋白、血尿素氮、血肌酐和肾脏ERK的表达明显升高(P0.05);与模型组比较,丝胶蛋白组空腹血糖、24 h尿蛋白、血尿素氮、血肌酐和肾脏ERK的表达明显降低,差异有统计学意义(P0.05)。结论丝胶可能通过降低血糖影响肾脏ERK的激活,从而改善糖尿病肾脏损害。 相似文献
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目的观察胞外信号调节激酶(ERK1)在人纤维化肝组织中的表达,探讨ERK1在肝纤维化发生中的作用机制。方法采用SABC免疫组化方法,对2001—01~2003—12华中科技大学附属同济医学院及广西壮族自治区人民医院外科手术切除的诊断明确的44例病理存档标本(其中包括12例正常肝组织、32例慢性乙型病毒性肝炎和肝硬化组织)中ERK1的表达及分布进行检测。结果免疫组化显示,ERK1主要表达于肝星状细胞(HSC)中。正常肝组织中,仅在汇管区少量非实质细胞中见ERK1弱阳性表达。在纤维化肝组织中,ERK1表达水平明显增强,与正常肝组织相比差异有显著性(P〈0.01)。结论ERK激活促进了HSC活化增殖,参与了肝纤维化的发生发展过程。 相似文献
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目的观察胞外信号调节激酶(ERK1)在人纤维化肝组织中的表达,探讨ERK1在肝纤维化发生中的作用机制。方法采用SABC免疫组化方法,对2001-01~2003-12华中科技大学附属同济医学院及广西壮族自治区人民医院外科手术切除的诊断明确的44例病理存档标本(其中包括12例正常肝组织、32例慢性乙型病毒性肝炎和肝硬化组织)中ERK1的表达及分布进行检测。结果免疫组化显示,ERK1主要表达于肝星状细胞(HSC)中。正常肝组织中,仅在汇管区少量非实质细胞中见ERK1弱阳性表达。在纤维化肝组织中,ERK1表达水平明显增强,与正常肝组织相比差异有显著性(P<0.01)。结论ERK激活促进了HSC活化增殖,参与了肝纤维化的发生发展过程。 相似文献
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目的 观察丝裂素活化蛋白激酶的上游激酶1(MAPKK,MEK1)抑制剂PD98059对大鼠甲状旁腺素1-34(rPTH1-34)诱导的心室肌细胞肥大的影响及细胞外信号调节激酶1/2(ERK1/2)表达的变化,分析MEK/ERK途径的可能作用. 方法 体外培养新生大鼠心室肌细胞,10-7mol/LrPTH1-34诱导建立心肌细胞肥大模型,在模型中加入2×10-5mol/L PD98059,Motic Images Advanced 3.0软件测定细胞直径、3H-亮氨酸掺入实验检测细胞蛋白合成速率、RT-PCR半定量测定心房利钠肽mRNA、Western blot方法观察ERK1/2、磷酸化ERK1/2蛋白表达的变化. 结果 与正常组相比,10-7mol/L rPTH1-34孵育24 h可使体外培养的心肌细胞直径增加13.6 μm、细胞蛋白合成速率增加898 cpm/well,使心房利钠肽mRNA表达增加73.9%,p-ERK1/2蛋白表达增加15%(P<0.05).与PTH组相比,预先给予PD98059可使细胞直径减少7.1 μm,细胞蛋白合成速率减少644 cpm/well,心房利钠肽mRNA表达下降52.2%,磷酸化ERK1/2蛋白表达减少18%(P<0.05).单独使用PD98059对正常心肌细胞没有影响(P>0.05). 结论 PD98059通过抑制ERK1/2、磷酸化ERK1/2的表达阻断了心肌细胞肥大反应,MEK/ERK1/2途径的活化参与了rPTH1-34的致肥大作用. 相似文献
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Hypoxemia in the circulation can lead to venous thrombosis (VT) through tissue factor (TF) activation, but the mechanism of TF activation in hypoxia remains obscure. Ligands released from damaged tissues or cells due to hypoxia are identified by various pattern-recognition receptors (PRR), including Toll-like receptor3 (TLR3). In the present study, we investigated the mechanism of TF activation during acute hypoxia in a rat model. The expression of TLR3 and TF was analyzed by immunoblotting and RT-PCR. The TF activity was evaluated by two-stage chromogenic assay and fibrin deposition was detected by immunohistochemistry. The expression of TLR3, TF, and TF activity was increased significantly 6 h post acute hypoxia and then decreased gradually. The contribution of TLR3 in TF activation was investigated by poly I:C and TLR3 neutralizing antibody. We also found increased ERK phosphorylation both in acute hypoxia and poly I:C treatment. We further showed that the pre-treatment of TLR3 neutralizing antibody or ERK inhibitor (PD98059) 2 h prior to acute hypoxia or poly I:C treatment completely abrogated ERK phosphorylation and TF activation. The pre-treatment of TLR3 neutralizing antibody also inhibited fibrin deposition in lung vasculature. These data indicate that acute hypoxia induced TF activation is mediated through TLR3-ERK1/2 pathway. 相似文献
19.
目的 从新疆株细粒棘球蚴中克隆细胞外信号调节激酶(EgERK1)基因,进行序列测定、生物信息学分析,蛋白表达及功能初步鉴定.方法 设计特异性引物,从新疆株细粒棘球蚴中提取总RNA,RT-PCR法扩增EgERK1基因,构建pET28a-EgERK1原核表达质粒,测序确定序列并进行生物信息学分析.构建正确的pET28a-EgERK1原核表达质粒,经诱导、表达EgERK1重组蛋白,聚丙烯酰胺凝胶电泳和Western印迹检测其生物学功能.结果 RT-PCR扩增出的条带经测序,结果显示其长度为1125 bp,编码374个氨基酸,等电点为6.34,BLAST比对结果提示为一薪基因,命名为EgERK1(EU701008).同源性比较表明,EgERK1与多房棘球绦虫ERK基因(EmMPK1)同源性为95.45%,与线虫、酵母、果蝇和人类等ERK基因的同源性为43.04%~61.88%.进化树分析发现EgERK1和EmMPK1相聚集.功能分析预测EgERK1具有ERK类激酶T-X-Y结构保守区和酶激活功能域.Western印迹显示,原核诱导表达的EgERK1重组蛋白能与抗人ERK1/2抗体发生特异性免疫反应.结论 成功克隆细粒棘球蚴EgERK1新基因,发现EgERK1重组蛋白具有与ERK1/2抗体结合的功能,为进一步研究该基因在寄生虫与宿主相互作用中的功能奠定基础. 相似文献