Objective： To clone, express, and identify the extracellular domain gene of human p75 neurotrophin receptor with IgG-Fe （hp75NTR-Fc） in prokaryotic expression system, and investigate the effect of the recombinant p...Objective： To clone, express, and identify the extracellular domain gene of human p75 neurotrophin receptor with IgG-Fe （hp75NTR-Fc） in prokaryotic expression system, and investigate the effect of the recombinant protein on dorsal root ganglia （DRG） neuron neurites. Methods： The hp75NTR-Fc coding sequence was amplified from pcDNA-hp75NTR-Fc by polymerase chain reaction （PCR） and subcloned into vector pET30a （＋）, in which hp75NTR-Fc expression was controlled under the T7 promoter. The recombinant vectors were amplified in E. coli DH5α and identified by PCR, enzyme digestion and sequencing, and then transformed into E. coli BL21 （DE3）. The expression product was analyzed with SDS-PAGE and Western blot. Then after the recombinant protein purified with Protein A affinity chromatograph, and renaturated with dialysis, respectively, the effect of the recombinant protein on DRG neuron neuritis was further investigated. Results： The results of PCR, enzyme digestion, and sequencing demonstrated the success of inserting the hp75NTR-Fc fragment into vector pET30a （＋）. SDS-PAGE and Western blot showed a positive protein band with molecular weight about 50 kD in the expression product, which is accordant with the interest protein, and this band could be specifically recognized by rabbit anti-NGFRp75 antibody. The purified infusion protein following dialysis could promote neurite outgrowth of DRG neurons cultured with myelin-associated glycoprotein （MAG）. Conclusion： The hp75NTR-Fc coding sequence was subcloned into the expression vector pET30a （＋） correctly and expressed successfully in the prokaryotie expression system. The infusion protein could promote neurite outgrowth of DRG neurons cultured with MAG.展开更多
In order to investigate the functions of the gene PsG6PDH and the mechanisms underlying freezing tolerance of Populus suaveolens, the recombinant expression vector pET-G （pET30a-G6PDH）, which contained full encoding...In order to investigate the functions of the gene PsG6PDH and the mechanisms underlying freezing tolerance of Populus suaveolens, the recombinant expression vector pET-G （pET30a-G6PDH）, which contained full encoding region of PsG6PDH gene, was established. The recombinant was identified by lawn-PCR and double enzyme digestion and then transformed into expression host XA90 and induced by isopropyl-a-D-thiogalactoside （IPTG） to express 100 kD polypeptide of G6PDH fusion protein. The results showed that the expressed amount of the fusion protein culminated after 1 mmol·L^-1 IPTG treatment for 4h and that pET-G product was predominately soluble and not extra-cellular secreting.展开更多
In order to investigate the enzymatic properties of the 4CL1 of Populus tomentosa, the recombinant expression vector pQE31-4CL 1 was constructed. The recombinant was identified by three restriction endonucleases, then...In order to investigate the enzymatic properties of the 4CL1 of Populus tomentosa, the recombinant expression vector pQE31-4CL 1 was constructed. The recombinant was identified by three restriction endonucleases, then the vector pQE31-4CL 1 was transformed into expression host M15 （pREP4） and induced by isopropyl-a-D-thiogalactoside （IPTG） to express 60 kD fused protein Pt4CL1. The biologically active Pt4CL1, expressed as soluble protein, was achieved with 0.6 mmol＇L-1 IPTG induction as the expression temperature declined from 37 to 28℃. The 6-His tag facilitates affinity binding to Ni^2＋-nitrolotriacetic acid （NTA） and enables one-step purification to acquire the molecular SDS-PAGE electrophoresis purity of the active 4CL1 protein by agarose coupled with Ni^2＋-NTA affinity chromatography. The optimal substrate for Pt4CL 1 was 4-coumarate.展开更多
This study is conducted to clone the cDNA encoding human TNF-related apoptosis-inducing ligand (hTRAIL) extracellular region (amino acids 41-281, hTRAIL41-281) and to express it in E.coli. The hTRAIL41-281 cDNA is amp...This study is conducted to clone the cDNA encoding human TNF-related apoptosis-inducing ligand (hTRAIL) extracellular region (amino acids 41-281, hTRAIL41-281) and to express it in E.coli. The hTRAIL41-281 cDNA is amplified by reverse transcription (RT) PCR from total RNA derived from human acute promyelocytic leukemia cell line HL-60. After sequenced, the cDNA is cloned into the vector pQE-80L and transformed into E.coli DH5 to express the recombinant hTRAIL41-281 (rhTRAIL41-281) induced by IPTG. The recombinant protein is analyzed by SDS-PAGE. The cloned cDNA is consistent with the cDNA sequence encoding hTRAIL41-281 reported in GenBankTM. After inducing, the hTRAIL41-281 protein is expressed, and the mass of the recombinant protein is about 30 % of total bacteria protein, which demonstrates that the cDNA encoding hTRAIL41-281 is successfully cloned and expressed in E.coli.展开更多
Objective To examine the inhibitory effects of recombinant purified arresten on tumor formation. Methods Purified arresten protein was incubated with human umbilical vein endothelial cells (HUVECs) and HeLa cells in v...Objective To examine the inhibitory effects of recombinant purified arresten on tumor formation. Methods Purified arresten protein was incubated with human umbilical vein endothelial cells (HUVECs) and HeLa cells in vitro. The effect on proliferation of HUVECs and HeLa cells was examined using 3-(4,5)-dimethylthiahiazo (-z-y1)-3,5-di-phenytetrazoliumromide assay, and apoptosis of these cells monitored by flow cytometry. The effect on migration of HUVECs and HeLa cells was examined by Boyden chamber. Twenty colon carcinoma-bearing C67BL/6 mice were used to investigate the antitumor effects of arresten protein. The mice were randomly divided into arresten treatment group (n=10) and control group (n=10). The microvessel densities of the tumors were measured by immunohistochemical staining with anti-CD31 monoclonal antibody. Results Arresten inhibited the proliferation and migration of HUVECs in a dose-dependent manner while promoting apoptosis. However, arresten had no significant effects on the proliferation and apoptosis of HeLa cells. The migration of HeLa cells was modestly inhibited by arresten. The arresten treatment group of mice showed no weight loss or unusual behavior during the course of treatment, and the tumor growth was significantly decreased; in contrast, the control group of mice exhibited rapidly growing tumors and cachexia. A dramatically decreased microvessel density in tumor tissues was found in arresten-treated mice compared with that in the control mice. Conclusion Arresten can inhibit tumor growth through inhibition of tumor angiogenesis.展开更多
基金Supported by the National Natural Science Foundation of China (30600665)the Natural Science Foundation Project of CQ CSTC (CSTC, 2008BB5107)+1 种基金the Youth Scientific Research Foundation of Third Military Medical University (06XG048)the Open Project Program of the State Key Laboratory of Trauma, Burns and Combined Injury (2006A-3)
文摘Objective： To clone, express, and identify the extracellular domain gene of human p75 neurotrophin receptor with IgG-Fe （hp75NTR-Fc） in prokaryotic expression system, and investigate the effect of the recombinant protein on dorsal root ganglia （DRG） neuron neurites. Methods： The hp75NTR-Fc coding sequence was amplified from pcDNA-hp75NTR-Fc by polymerase chain reaction （PCR） and subcloned into vector pET30a （＋）, in which hp75NTR-Fc expression was controlled under the T7 promoter. The recombinant vectors were amplified in E. coli DH5α and identified by PCR, enzyme digestion and sequencing, and then transformed into E. coli BL21 （DE3）. The expression product was analyzed with SDS-PAGE and Western blot. Then after the recombinant protein purified with Protein A affinity chromatograph, and renaturated with dialysis, respectively, the effect of the recombinant protein on DRG neuron neuritis was further investigated. Results： The results of PCR, enzyme digestion, and sequencing demonstrated the success of inserting the hp75NTR-Fc fragment into vector pET30a （＋）. SDS-PAGE and Western blot showed a positive protein band with molecular weight about 50 kD in the expression product, which is accordant with the interest protein, and this band could be specifically recognized by rabbit anti-NGFRp75 antibody. The purified infusion protein following dialysis could promote neurite outgrowth of DRG neurons cultured with myelin-associated glycoprotein （MAG）. Conclusion： The hp75NTR-Fc coding sequence was subcloned into the expression vector pET30a （＋） correctly and expressed successfully in the prokaryotie expression system. The infusion protein could promote neurite outgrowth of DRG neurons cultured with MAG.
文摘In order to investigate the functions of the gene PsG6PDH and the mechanisms underlying freezing tolerance of Populus suaveolens, the recombinant expression vector pET-G （pET30a-G6PDH）, which contained full encoding region of PsG6PDH gene, was established. The recombinant was identified by lawn-PCR and double enzyme digestion and then transformed into expression host XA90 and induced by isopropyl-a-D-thiogalactoside （IPTG） to express 100 kD polypeptide of G6PDH fusion protein. The results showed that the expressed amount of the fusion protein culminated after 1 mmol·L^-1 IPTG treatment for 4h and that pET-G product was predominately soluble and not extra-cellular secreting.
文摘In order to investigate the enzymatic properties of the 4CL1 of Populus tomentosa, the recombinant expression vector pQE31-4CL 1 was constructed. The recombinant was identified by three restriction endonucleases, then the vector pQE31-4CL 1 was transformed into expression host M15 （pREP4） and induced by isopropyl-a-D-thiogalactoside （IPTG） to express 60 kD fused protein Pt4CL1. The biologically active Pt4CL1, expressed as soluble protein, was achieved with 0.6 mmol＇L-1 IPTG induction as the expression temperature declined from 37 to 28℃. The 6-His tag facilitates affinity binding to Ni^2＋-nitrolotriacetic acid （NTA） and enables one-step purification to acquire the molecular SDS-PAGE electrophoresis purity of the active 4CL1 protein by agarose coupled with Ni^2＋-NTA affinity chromatography. The optimal substrate for Pt4CL 1 was 4-coumarate.
基金Funded by the Scientific Research Foundation of the Third Military Medical University.
文摘This study is conducted to clone the cDNA encoding human TNF-related apoptosis-inducing ligand (hTRAIL) extracellular region (amino acids 41-281, hTRAIL41-281) and to express it in E.coli. The hTRAIL41-281 cDNA is amplified by reverse transcription (RT) PCR from total RNA derived from human acute promyelocytic leukemia cell line HL-60. After sequenced, the cDNA is cloned into the vector pQE-80L and transformed into E.coli DH5 to express the recombinant hTRAIL41-281 (rhTRAIL41-281) induced by IPTG. The recombinant protein is analyzed by SDS-PAGE. The cloned cDNA is consistent with the cDNA sequence encoding hTRAIL41-281 reported in GenBankTM. After inducing, the hTRAIL41-281 protein is expressed, and the mass of the recombinant protein is about 30 % of total bacteria protein, which demonstrates that the cDNA encoding hTRAIL41-281 is successfully cloned and expressed in E.coli.
基金Supported by Key Scientific and Technological Project of Shanxi Province (042082)Technological and Engineering Project of the Department of Education of Shanxi Province (20080017)
文摘Objective To examine the inhibitory effects of recombinant purified arresten on tumor formation. Methods Purified arresten protein was incubated with human umbilical vein endothelial cells (HUVECs) and HeLa cells in vitro. The effect on proliferation of HUVECs and HeLa cells was examined using 3-(4,5)-dimethylthiahiazo (-z-y1)-3,5-di-phenytetrazoliumromide assay, and apoptosis of these cells monitored by flow cytometry. The effect on migration of HUVECs and HeLa cells was examined by Boyden chamber. Twenty colon carcinoma-bearing C67BL/6 mice were used to investigate the antitumor effects of arresten protein. The mice were randomly divided into arresten treatment group (n=10) and control group (n=10). The microvessel densities of the tumors were measured by immunohistochemical staining with anti-CD31 monoclonal antibody. Results Arresten inhibited the proliferation and migration of HUVECs in a dose-dependent manner while promoting apoptosis. However, arresten had no significant effects on the proliferation and apoptosis of HeLa cells. The migration of HeLa cells was modestly inhibited by arresten. The arresten treatment group of mice showed no weight loss or unusual behavior during the course of treatment, and the tumor growth was significantly decreased; in contrast, the control group of mice exhibited rapidly growing tumors and cachexia. A dramatically decreased microvessel density in tumor tissues was found in arresten-treated mice compared with that in the control mice. Conclusion Arresten can inhibit tumor growth through inhibition of tumor angiogenesis.
